National Oil and Hazardous Substances Pollution Contingency Plan; Monitoring Requirements for Use of Dispersants and Other Chemicals, 40234-40264 [2021-15122]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 86, Number 141 (Tuesday, July 27, 2021)]
[Rules and Regulations]
[Pages 40234-40264]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-15122]



[[Page 40233]]

Vol. 86

Tuesday,

No. 141

July 27, 2021

Part II





 Environmental Protection Agency





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40 CFR Part 300





National Oil and Hazardous Substances Pollution Contingency Plan; 
Monitoring Requirements for Use of Dispersants and Other Chemicals; 
Final Rule

Federal Register / Vol. 86, No. 141 / Tuesday, July 27, 2021 / Rules 
and Regulations

[[Page 40234]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 300

[EPA-HQ-OPA-2006-0090; FRL-4526.1-01-OLEM]
RIN 2050-AH16


National Oil and Hazardous Substances Pollution Contingency Plan; 
Monitoring Requirements for Use of Dispersants and Other Chemicals

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA or the Agency) is 
amending the requirements in Subpart J of the National Oil and 
Hazardous Substances Pollution Contingency Plan (NCP) that govern the 
use of dispersants, other chemicals and other spill mitigating 
substances when responding to oil discharges into waters of the United 
States. Specifically, this action establishes monitoring requirements 
for dispersant use in response to major oil discharges and/or certain 
dispersant use situations in the navigable waters of the United States 
and adjoining shorelines, the waters of the contiguous zone, and the 
high seas beyond the contiguous zone in connection with activities 
under the Outer Continental Shelf Lands Act, activities under the 
Deepwater Port Act of 1974, or activities that may affect natural 
resources belonging to, appertaining to, or under the exclusive 
management authority of the United States, including resources under 
the Magnuson Fishery Conservation and Management Act of 1976 
(``navigable waters of the United States and adjoining shorelines''). 
These new monitoring requirements are anticipated to better target 
dispersant use, thus reducing the risks to the environment. Further, 
the amendments are intended to ensure that On-Scene Coordinators (OSCs) 
and Regional Response Teams (RRTs) have relevant information to support 
response decision-making regarding dispersant use.

DATES: This final rule is effective on January 24, 2022.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-HQ-OPA-2006-0090. All documents in the docket are listed on the 
https://www.regulations.gov website. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, is not placed on the internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available electronically through https://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: For general information, contact the 
Superfund, TRI, EPCRA, RMP, and Oil Information Center at 800-424-9346 
or TDD at 800-553-7672 (hearing impaired). In the Washington, DC 
metropolitan area, contact the Superfund, TRI, EPCRA, RMP, and Oil 
Information Center at 703-412-9810 or TDD 703-412-3323. For more 
detailed information on this final rule contact Gregory Wilson at 202-
564-7989 ([email protected]). The contact address is: U.S. 
Environmental Protection Agency, Office of Emergency Management, 
Regulations Implementation Division, 1200 Pennsylvania Avenue NW, 
Washington, DC 20460-0002, Mail Code 5104A, or visit the Office of 
Emergency Management website at https://www.epa.gov/oem/.

SUPPLEMENTARY INFORMATION: The contents of this preamble are:
I. General Information
II. Entities Potentially Affected by This Proposed Rule
III. Statutory Authority and Delegation of Authority
IV. Background
V. This Action
    A. Monitoring the Use of Dispersants
    B. Information on Dispersant Application
    C. Water Column Sampling
    D. Oil Distribution Analyses
    E. Ecological Characterization
    F. Immediate Reporting
    G. Daily Reporting
VI. Overview of New Rule Citations
VII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Environmental Justice (EJ)
    K. Congressional Review Act (CRA)
Part 300--National Oil and Hazardous Substances Pollution 
Contingency Plan

I. General Information

    In April 2010, the Deepwater Horizon underwater oil well blowout 
discharged significant quantities of oil into the Gulf of Mexico. The 
blowout discharged oil from one mile below the sea surface. 
Approximately one million gallons of dispersants over a three-month 
period were deployed on surface slicks over thousands of square miles 
of the Gulf, and approximately three quarters of a million additional 
gallons of dispersants were, for the first time, injected directly into 
the oil gushing from the well riser. This raised questions about the 
challenges of making dispersant use decisions in response operations 
for certain atypical dispersant use situations. EPA is establishing new 
monitoring requirements under Subpart J of the National Oil and 
Hazardous Substances Pollution Contingency Plan (NCP) to address these 
challenges. Specifically in this action, the Agency establishes 
monitoring requirements for dispersant use in response to major 
discharges and/or certain dispersant use situations: Any subsurface use 
of dispersant in response to an oil discharge, surface use of 
dispersant in response to oil discharges of more than 100,000 U.S. 
gallons occurring within a 24-hour period, and surface use of 
dispersant for more than 96 hours after initial application in response 
to an oil discharge. These new requirements are intended to address the 
challenges of atypical dispersant use situations, including those 
identified during Deepwater Horizon.
    EPA estimates industry may incur a total incremental cost of 
approximately $32,000 to $3.0 million annually. Note that the 
annualized cost is the same for both the 3% and 7% discount rates 
because the cost is the same every year prior to being annualized. This 
action does not impose significant impacts on a substantial number of 
small entities. The Regulatory Impact Analysis, which can be found in 
the docket, provides more detail on the cost methodology and benefits 
of this action.

[[Page 40235]]



                         Cost of the Final Rule
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                                             Annualized cost, 20 years
                                         -------------------------------
                                           Annualized at   Annualized at
                                                3%              7%
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Scenario 1--Low End.....................         $32,124         $32,124
Scenario 4--High End....................       3,033,569       3,033,569
------------------------------------------------------------------------

II. Entities Potentially Affected by This Proposed Rule

------------------------------------------------------------------------
            NAICS code                       Industrial category
------------------------------------------------------------------------
211120............................  Crude Petroleum Extraction.
211130............................  Natural Gas Extraction.
324110............................  Petroleum Refineries.
424710............................  Petroleum Bulk Stations and
                                     Terminals.
424720............................  Petroleum and Petroleum Products
                                     Merchant Wholesalers (except Bulk
                                     Stations and Terminals).
483111............................  Deep Sea Freight Transportation.
483113............................  Coastal and Great Lakes Freight
                                     Transportation.
486110............................  Pipeline Transportation of Crude
                                     Oil.
------------------------------------------------------------------------

    The list of potentially affected entities in the above table 
includes oil exploration and production industries with the potential 
for an oil discharge into navigable waters of the United States and 
adjoining shorelines. The Agency's goal is to provide a guide for 
readers to consider regarding entities that potentially could be 
affected by this action. However, this action may affect other entities 
not listed in this table. If you have questions regarding the 
applicability of this action to a particular entity, consult the 
person(s) listed in the preceding section entitled FOR FURTHER 
INFORMATION CONTACT.

III. Statutory Authority and Delegation of Authority

    Under sections 311(d) and 311(j) of the Clean Water Act (CWA), as 
amended by section 4201 of the Oil Pollution Act of 1990 (OPA), Public 
Law 101-380, the President is directed to prepare and publish the NCP 
for removal of oil and hazardous substances. Specifically, section 
311(d)(2)(G) directs the President to include a Schedule identifying 
``(i) dispersants, other chemicals, and other spill mitigating devices 
and substances, if any, that may be used in carrying out the Plan, (ii) 
the waters in which such dispersants, other chemicals, and other spill 
mitigating devices and substances may be used, and (iii) the quantities 
of such dispersant, other chemicals, or other spill mitigating device 
or substance which can be used safely in such waters'' as part of the 
NCP. The Agency has promulgated both the NCP, see 40 CFR 300.1 et seq., 
and the schedule of dispersants as required by section 311 (d)(2)(G), 
known as the NCP product schedule. See 40 CFR 300.900 et. seq. The 
President is further authorized to revise or otherwise amend the NCP 
from time to time, as the President deems advisable. 33 U.S.C. 
1321(d)(3). The authority of the President to implement section 
311(d)(2)(G) of the CWA is delegated to EPA in Executive Order 12777 
(56 FR 54757, October 22, 1991). Subpart J of the NCP establishes the 
framework for the use of dispersants and any other chemical agents in 
response to oil discharges (40 CFR part 300 series 900).

IV. Background

    In the United States and around the world, chemical agents are 
among the oil spill mitigation technologies available that responders 
may consider. Subpart J of the NCP sets forth the regulatory 
requirements for the use of chemical agents, including provisions for 
product testing and listing, and for authorization of use procedures. 
These requirements provide the structure for the On-Scene Coordinator 
(OSC) to determine in each case the waters and quantities in which 
dispersants or other chemical agents may be safely used in such waters. 
This determination is based on all relevant circumstances, testing and 
monitoring data and information, and is to be made in accordance with 
the authorization of use procedures, including the appropriate 
concurrences and consultations, found within the regulation. When taken 
together, the Subpart J regulatory requirements address the types of 
waters and the quantities of listed agents that may be authorized for 
use in response to oil discharges. EPA believes the wide variability in 
waters, weather conditions, organisms living in the waters, and types 
of oil that might be discharged requires this approach.
    The Deepwater Horizon underwater oil well blowout in 2010 raised 
questions about the challenges of making chemical agent use decisions 
in response operations, particularly for certain atypical dispersant 
use situations. To address these challenges, in 2015 the Agency 
proposed amendments to Subpart J of the NCP that included revisions to 
the existing product listing, testing protocols, and authorization of 
use procedures, as well as new provisions for dispersant monitoring. 
The proposed new monitoring provisions under Subpart J were focused on 
dispersant use in response to major oil discharges and on certain 
dispersant use situations in the navigable waters of the United States 
and adjoining shorelines. The proposed new monitoring provisions were 
also aimed at ensuring that the response community is equipped with 
relevant data and information to authorize and use the products in a 
judicious and effective manner. Final action on the proposed revisions 
to the product listing, testing protocols, and authorization of use 
procedures will be taken separately from this action.

V. This Action

    This final action addresses environmental monitoring of dispersant 
use in response to major discharges and to certain dispersant use 
situations. Specifically, in this action, the Agency establishes 
monitoring requirements for any subsurface use of dispersant in 
response to an oil discharge, surface use

[[Page 40236]]

of dispersant in response to oil discharges of more than 100,000 U.S. 
gallons occurring within a 24 hour period, and surface use of 
dispersant for more than 96 hours after initial application in response 
to an oil discharge. The discussion below explains the specific 
requirements and also summarizes and responds to public comments 
received on the proposal.

A. Monitoring the Use of Dispersants

    The goal of establishing a Schedule under the NCP is to protect the 
environment from possible damage related to spill mitigating products 
used in response to oil discharges. The new monitoring requirements for 
certain discharge situations in this action supplements the existing 
regulatory provisions under Subpart J which already include test data 
and information requirements for chemical agents as well as procedures 
for authorizing the use of those agents to respond to oil discharges 
and threats of discharge.
    The new Sec.  300.913 establishes requirements for the responsible 
party to monitor any subsurface use of dispersant in response to an oil 
discharge, surface use of dispersant in response to oil discharges of 
more than 100,000 U.S. gallons occurring within a 24 hour period, and 
surface use of dispersant for more than 96 hours after initial 
application in response to an oil discharge, and to submit a Dispersant 
Monitoring Quality Assurance Project Plan (DMQAPP) to the OSC. The 
requirements are established for the responsible party as they operate 
in those environments where applicable discharges may occur and should 
be in the best position to monitor the response. The Agency removed 
language included in the proposal that specified these actions were to 
be taken ``As directed by OSC . . .''. The clarification in this action 
is unnecessary as 33 U.S.C. 1321 and Sec.  300.120 of the NCP already 
establish the OSC's oversight role over the responsible party. The 
Agency has also changed language associated with the DMQAPP to remove 
the proposed ``for approval'' qualifier in this final action. The 
change is to better reflect that the requirement to develop the DMQAPP 
is directed at the responsible party, and that the provision is not 
intended to establish a DMQAPP approval timeline for the OSC relative 
to dispersant use. Rather, the DMQAPP submission is intended to provide 
the OSC, and other agencies with NCP responsibilities, with a better 
understanding of the monitoring data to inform dispersant use 
decisions. The OSC may request that response support agencies provide 
feedback on the submitted DMQAPP and has the discretionary authority to 
require the responsible party to address any concerns associated with 
it. The responsible party is required to implement the new monitoring 
requirements when these dispersant use conditions are met, and for the 
duration of dispersant operations. The monitoring and data submissions 
that serve as the basis of this rule were established in the 2013 
National Response Team (NRT) Environmental Monitoring for Atypical 
Dispersant Operations document. The Agency is aware that industry and 
OSROs have been preparing to monitor dispersant use this rule since the 
issuance of the NRT guidance document in 2013. The Agency encourages 
the continuation of planning and preparedness efforts and continues to 
support these efforts with our interagency partners.
    Subpart J of the NCP is intended to provide tools that support 
planning for and responding to oil discharges. To this end, the 
monitoring requirements for certain discharge situations promulgated in 
this final rule serve as a complement to the existing regulatory 
approach under Subpart J. When dispersants are applied in response to 
an oil discharge, environmental field monitoring data can support 
decision-making in dispersant use operations by gathering site-specific 
information on the overall effectiveness, including the transport and 
environmental effects of the dispersants and the dispersed oil. 
Environmental field monitoring data is at the core of any response, as 
without it the extent of the problem cannot be evaluated nor can a path 
forward for an appropriate response be established.
    The purpose of monitoring subsurface application is to characterize 
the dispersed oil, follow the plume integrity and transport with the 
underwater current, and identify and assess the potential adverse 
effects from the dispersed oil. Product testing conducted under 
standardized laboratory conditions is useful for comparison between 
different products. However, standardized laboratory conditions do not 
necessarily reflect field conditions. Monitoring of agents in the field 
informs the OSC and support agencies on the overall effectiveness of 
dispersant use, including the environmental effects and transport of 
dispersed oil. These new monitoring requirements, in conjunction with 
the existing testing and information requirements for chemical agents, 
and the procedures for authorizing the use of those agents, serve to 
protect the environment from possible damage related to spill 
mitigating products used.
1. General
    Several Non-Governmental Organizations (NGO), private citizens, and 
local, state, and federal government agencies generally supported the 
proposed new monitoring requirements, with some also requesting some 
clarifications. A commenter stated that while they agree with the 
concept of requiring monitoring for dispersant use, the current 
language undermines the contingency planning process and illegally 
assigns responsibilities to the OSC and the responsible party. The 
commenter stated this usurps authority from all other agencies, tribes 
and the public, which they see as a breach of the responsibilities of 
the federal government to protect public trust resources.
    The Agency agrees with commenters expressing support for this final 
action. The Agency disagrees with the comments that this action 
undermines the contingency planning process and illegally assigns 
responsibilities to the OSC and the responsible party. The EPA 
acknowledges the importance of effective contingency planning to the 
achievement of a timely and effective response. Planning and 
preparedness provisions are currently addressed under Subpart C of the 
NCP or as codified in regulations implementing CWA 311(j)(5) 
authorities as delegated to other NRT member agencies by E.O. 12777. 
The Agency is amending the proposed language in the opening paragraph 
of the monitoring section to clarify the new provisions are for the 
responsible party to implement. EPA disagrees with comments that state 
the structure of the new monitoring requirements usurps other 
governmental authorities or constitutes a breach of responsibilities of 
the federal government to protect public trust resources. The NCP 
designates the OSC as the person who is authorized to direct response 
efforts and to coordinate all other efforts at the scene of a 
discharge, including the new monitoring requirements. The NCP 
designates those Agencies providing the OSC for a response, including 
designating USCG to provide the OSC for oil spills into or threatening 
the coastal zone. See, e.g., 40 CFR 300.120. The NCP requires that the 
OSC ensure that the natural resource trustees are promptly notified in 
the event of any discharge of oil to the maximum extent practicable as 
provided in the Fish and Wildlife and Sensitive Environments Plan annex 
to the Area Contingency Plan (ACP) for the area in which the

[[Page 40237]]

discharge occurs. The NCP also directs the OSC and the trustees to 
coordinate assessments, evaluations, investigations, and planning with 
respect to appropriate removal actions, including the OSC consulting 
with the affected trustees on the appropriate removal action to be 
taken. Finally, none of new requirements in this action in any way 
limit current existing NCP authorities, but rather they inform the OSC 
and facilitate compliance with regulatory responsibilities.
    Several commenters supported the proposed amendments and suggested 
the monitoring requirements be extended to all products listed on the 
Product Schedule. Another commenter expressed similar concerns, stating 
that monitoring should occur anytime any product is used during a 
response activity. The commenter suggested these additional 
requirements for product effectiveness data would then be available for 
future releases, allowing for a refined set of response options. 
Another commenter stated that EPA should include language indicating 
that the new monitoring requirements are a minimum and that additional 
monitoring may be required based on conditions, dispersant type, and 
location. A commenter also recommended that, at a minimum, the 
requirements include monitoring of public health effects following the 
dispersant application.
    The Agency interprets the specific requirements set forth in this 
final action as the minimum set of monitoring activities expected 
during a response involving the atypical dispersant use conditions 
specified. However, the Agency does not believe it is necessary to 
amend regulatory text for this purpose. The new requirements in no way 
impede the existing OSC authority \1\ to direct the responsible party 
to conduct additional monitoring if deemed necessary due to incident-
specific circumstances including location, oil type, or conditions of 
use. EPA notes that incident-specific circumstances may extend beyond 
the examples provided. The incident-specific data gathered through 
these new monitoring requirements, in conjunction with the OSC 
authority to direct additional monitoring, offers flexibility in 
accounting for differences in regional environments that may have the 
potential to impact any discharge situation. The USCG provides a 
designated OSC for oil discharges into or threatening the coastal zone 
as per 40 CFR 300.120. The OSC authorizes the use of chemical agents in 
accordance with Subpart J and other applicable provisions of the NCP.
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    \1\ See 33 U.S.C. 1321(c); See also 40 CFR 300.120, 40 CFR 
300.305.
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    The Agency reiterates that the new provisions are focused on 
environmental monitoring and are applicable only to the following 
atypical dispersant use situations: any subsurface use of dispersant in 
response to an oil discharge, surface use of dispersant in response to 
oil discharges of more than 100,000 U.S. gallons occurring within a 24-
hour period, and any surface use of dispersant for more than 96 hours 
after initial application in response to an oil discharge. However, 
these new requirements in no way preclude the OSC from directing the 
monitoring of any substance, including chemical agents used, or their 
use within different time frames than those listed above, as part of 
the existing authorities set forth in the NCP. The Agency is clarifying 
the applicability provisions of the monitoring requirements relative to 
the duration of their implementation. Specific to subsurface 
application of dispersants, the Agency is offering language further 
clarifying the monitoring provisions are to be implemented for the 
entire duration of the subsurface dispersant use. For dispersant 
application on the surface in response to oil discharges situations of 
greater than 100,000 U.S. gallons occurring within a 24-hour period, 
the monitoring provisions are to be implemented as soon as possible for 
the entire or remaining duration of surface dispersant use, as 
applicable. Finally, for any dispersant used on the surface for more 
than 96 hours after initial application, the new monitoring provisions 
in this action are to be implemented for the remaining duration of 
surface dispersant use, consistent with the 2013 National Response Team 
(NRT) Environmental Monitoring for Atypical Dispersant Operations 
document. Additional discussion regarding this clarifying language is 
found in Section C of this preamble--Water Column Sampling.
    While the new provisions established in this action are specific to 
environmental monitoring, the Agency notes there are other impacts 
potentially resulting from an oil discharge and associated response 
operations that are addressed under different provisions of the NCP. Of 
note, the OSC initiates a preliminary assessment as per the NCP. This 
preliminary assessment is conducted using available information and is 
supplemented where necessary and possible by an on-scene inspection. 40 
CFR 300.305(a)-(b). The preliminary assessment undertaken by the OSC in 
accordance with 40 CFR 300.305 includes an evaluation of the threat to 
public health or welfare of the United States or the environment.
    A commenter suggested that for oil spill events where product 
preauthorization has not been granted, the rule should require that 
authorization of use be contingent on the Area Committee having a 
current Quality Assurance Project Plan (QAPP) approved by the RRT, NRT, 
and federally recognized Tribal representatives for the collection and 
reporting of all environmental data as part of the preauthorization 
plan. The commenter further suggested authorization be contingent on 
the Natural Resource Trustees having completed baseline ecosystem 
studies in the area impacted by the spill. Another commenter 
recommended that the development, approval, and update process for the 
QAPP be moved under the provisions for authorization of chemical agent 
use. They also suggested that withdrawal of concurrence, regarding 
product use following protocols also under authorization of use 
provisions, would mean that use of a product would cease until 
concurrence was reestablished.
    A commenter proposed that the Natural Resource Trustees should 
select and manage peer-reviewed scientific studies that implement the 
approved QAPP for spills where the preauthorization conditions for 
product use are met. The commenter suggested the Natural Resource 
Trustees seek concurrence from the Department of Labor/OSHA and 
Department of Human Health and Services/CDC representatives to the RRT, 
federally recognized Tribal representatives, and the RRT representative 
from the state(s) with jurisdiction over waters and adjoining 
shorelines within the geographic area impacted for these scientific 
studies. Other commenters generally suggested that the proposed 
requirements ensure peer-review as part of the monitoring process.
    The Agency recognizes that any monitoring to be conducted should 
follow a QAPP and has included new provisions to that effect. The 
Agency is modifying the provision by specifically requiring a DMQAPP to 
avoid confusion with the existing definition of a QAPP in the NCP. 
Further, given that the monitoring requirements are directed at the 
responsible party, the Agency believes it is most appropriate for the 
responsible party to develop a DMQAPP covering the environmental data 
collection, which includes quality assurance documentation. The DMQAPP 
developed by the responsible party is to be submitted to the OSC to

[[Page 40238]]

allow for a better understanding of the monitoring data. The Agency 
encourages the use of the guidance in Section 4.0 Quality Assurance 
Project Plan of the 2013 NRT Environmental Monitoring for Atypical 
Dispersant Operations document for preparation of the DMQAPP. EPA also 
encourages the RP to develop a DMQAPP, to the maximum extent possible, 
as part of the RP's response planning to facilitate monitoring 
preparedness among other members of the response community. The OSC has 
the expertise of the Scientific Support Coordinator (SSC) and other 
pertinent response agencies available to provide feedback on the 
submitted DMQAPP, as well as the discretionary authority to require the 
responsible party to address any concerns raised. For oil discharges in 
the coastal zone it is National Oceanic and Atmospheric Administration 
(NOAA) that generally provides the SSC. The Agency disagrees that these 
new monitoring provisions cannot be implemented without having a DMQAPP 
specifically included in the applicable ACP. Likewise, implementation 
of the new monitoring requirements has no impact on baseline ecosystem 
studies conducted by the Natural Resource Trustees. The Agency notes 
that the roles and responsibilities of the Natural Resource Trustees 
are delineated under the current NCP, and that commenters' 
recommendations specific to a DMQAPP evaluation by the Natural Resource 
Trustees to select and manage peer-reviewed scientific studies are 
outside the scope of this action. Similarly, issues regarding 
authorization of chemical agent use are outside of the scope of this 
action.
    A commenter supported the proposed monitoring requirements but 
suggested they include establishing baseline conditions prior to 
product application. Another commenter also suggested the requirements 
include pre-application monitoring of biological resources. A commenter 
suggested the concept of short-term damage assessments be included in 
this section, including rapid characterization of vulnerable aquatic 
species and habitats, and potential impacts to public health. 
Similarly, commenters also recommended longer-term monitoring and 
damage assessment activities as part of these new requirements; a 
commenter stated that monitoring should occur for the duration of the 
response and until the product is no longer detected in the water. 
Another commenter suggested that effects of dispersants on aquatic 
organisms may take longer to manifest themselves than the duration of 
monitoring that occurs during a spill response and therefore suggested 
that monitoring continue for several months following the dispersant 
application to allow for the assessment of both acute and chronic 
effects on fish and other species.
    EPA agrees with commenters who requested that the new monitoring 
requirements also include site-specific baseline monitoring, prior to 
application of dispersant, and is amending the proposed rule text to 
reflect this change in the final rule. The Agency believes this a 
rational and necessary addition since an understanding of baseline 
conditions is required for understanding the effects of dispersants in 
a specific area. The Agency believes that baseline monitoring will 
provide pre- and post-dispersant application data to better evaluate 
the effects, including physical dispersion, of the dispersants. Further 
details on this change to the proposed requirements is found in the 
Water Column Sampling discussion in this preamble. This final action 
also recognizes the need for ecological characterization. The new 
monitoring provisions include requirements for the responsible party to 
characterize the ecological receptors (e.g., aquatic species, wildlife, 
and/or other biological resources), their habitats, and exposure 
pathways that may be present in the discharge area. Specific comments 
on these new provisions are found in the Ecological Characterization 
discussion in this preamble. The Agency notes that the new monitoring 
provisions are for ecological monitoring of atypical dispersant use 
operations subject to this regulatory action (i.e., any subsurface 
dispersant use, prolonged surface dispersant use, and surface 
dispersant use in response to major discharges). Other potential 
impacts from an oil discharge and from other associated response 
operations are addressed under different provisions of the NCP. The OSC 
initiates a preliminary assessment under the NCP. This preliminary 
assessment is conducted using available information and is supplemented 
where necessary and possible by an on-scene inspection. The preliminary 
assessment includes an evaluation of the threat to public health or 
welfare of the United States or the environment.
    The Agency recognizes that some effects of dispersant use on the 
aquatic ecosystem may take longer to manifest than the duration of 
dispersant application or the monitoring time frames during a response. 
However, the new field monitoring provisions are designed to support 
and inform operational decisions by gathering site-specific information 
on the overall effectiveness, including the transport and environmental 
effects of the dispersant and the dispersed oil. Monitoring the overall 
effectiveness of dispersant use in the field provides the RRT member 
agencies with concurrence and consultation roles with information for 
operational decision making during atypical dispersant applications.
    Adverse effects on ecological receptors from exposures to 
dispersant use depend on the length of time and concentration of the 
exposure, which are dependent on the transport of the dispersed oil. 
Given that each oil discharge represents a unique situation, the Agency 
believes comprehensive monitoring is important for those discharge 
situations which are addressed in this final action. This monitoring 
data will enhance the information available for an effective response 
without delaying the use of dispersants. The Agency believes that 
comprehensive monitoring in certain discharge situations is necessary 
to determine the overall effectiveness of dispersants and should extend 
beyond the initial dispersant application to include the transport and 
potential environmental effects of the dispersant and dispersed oil in 
the water column. While all the data collected for dispersant 
operations purposes may be made available to Natural Resource Damage 
Assessment (NRDA) personnel as soon as practicable, the new monitoring 
requirements are intended to inform operational decision-making 
specific to atypical dispersant use; use of collected data in the NRDA 
process is incidental to this rulemaking. The NRDA data gathering 
efforts apply more broadly than just to dispersant use as part of the 
response.
    A commenter generally supported the concept of monitoring following 
dispersant use and recommended any monitoring data generated during a 
response acknowledge the uncertainty associated with the difficulty in 
estimating the effectiveness of dispersant actions in the field. A 
commenter recommended that EPA develop a set of standards for assessing 
dispersant application monitoring data in the field to supplement and 
validate results from laboratory-based studies.
    The Agency agrees that because of the nature of the operations, a 
certain degree of uncertainty associated with monitoring data generated 
during a response is to be expected. The Agency believes that the 
requirement for the responsible party to develop and submit a DMQAPP 
will help address some of those uncertainties. The Agency expects that 
the DMQAPP will address sample

[[Page 40239]]

collection methodology, handling, chain of custody, and decontamination 
procedures to ensure the highest quality data possible will be 
collected and maintained. The Agency disagrees that it should develop a 
set of standards for assessing dispersant application monitoring data 
in the field to supplement and validate results from laboratory-based 
studies. Product testing conducted under standardized laboratory 
conditions is useful for comparison between different products. 
However, standardized laboratory conditions do not necessarily reflect 
field conditions. The monitoring requirements in this final action are 
intended to supplement and compliment SMART procedures, as applicable, 
and inform the OSC and support agencies on the overall effectiveness of 
dispersant use for decision-making in the response.
    A commenter expressed concerns that the proposed requirements may 
not account for regional differences, which would be dealt with more 
effectively at the regional level, as opposed to the national level. 
This commenter also requested clarification on the distinction between 
dispersant efficacy and toxicity. The commenter suggested the reference 
to ``overall effectiveness'' is confusing and should be revised to 
clearly address both the effectiveness and toxicity of the dispersant 
and dispersed oil. The commenter also suggested that local field 
efficacy testing be conducted prior to dispersant use to understand 
site-specific conditions and that efficacy testing be conducted as 
outlined in the Special Monitoring of Applied Response Technologies 
(SMART) Tier I, Tier II, and Tier III protocols during the application 
monitoring. The commenter recommended that, if this type of monitoring 
is not possible, dispersant use be considered on a case-by-case basis 
as outlined under the regulatory provisions for authorization of 
chemical agent use.
    The Agency again notes the OSC has authority to direct additional 
monitoring and data collection beyond that which is specified in the 
new requirements, including for dispersant use situations outside the 
scope of the new provisions. This may include local field efficacy 
testing prior to dispersant use to better understand and account for 
site-specific conditions in operational decision-making. While the 
SMART protocols may be utilized in pre-deployment field testing and as 
part of the overall response, the atypical uses of dispersant during a 
response that are addressed in this action were neither envisioned nor 
addressed in the existing SMART monitoring program. The requirements in 
this final action follow recommendations from the Environmental 
Monitoring for Atypical Dispersant Operations: Including Guidance for 
Subsea Application and Prolonged Surface Application developed by NRT 
member agency representatives in 2013 and focus on monitoring atypical 
use of dispersants during an oil discharge in order to provide data for 
operational response decision-making. Further details on the SMART 
protocols can be found in the Field monitoring to support operational 
decisions discussion in this preamble.
    A commenter also requested clarification on the statement 
suggesting that subsurface dispersant application close to the release 
source reduces environmental impacts. They requested elaboration on the 
specifics of this statement in the context of the discussions of 
dispersant harm to aquatic organisms found in other places in the 
proposed rule. The commenter suggested elaborating on the language, or 
if there is inherent uncertainty, to allow RRTs to participate in 
research or testing associated with pre-authorization of dispersant use 
requests.
    The proposed rule preamble at 80 FR 3394 states: ``Equipment is 
being contemplated to inject dispersants subsurface, directly into the 
oil near the source of the discharge. This type of application is 
intended to minimize dispersant dilution in the water before the 
dispersant has had an opportunity to interact with the oil. This 
application approach that is closer to the source is expected to reduce 
potential adverse environmental consequences from the use of excessive 
quantities of dispersants. However, applying dispersant to an oil 
discharge does not result in the physical recovery of oil from the 
environment. Instead, dispersing oil increases the potential exposure 
of aquatic organisms to the dispersant-oil mixture, at least 
transiently, and subsurface application has the potential to more 
immediately and effectively increase these exposures near the 
discharge.'' EPA disagrees with the commenter that clarification is 
needed on the cited statement, as the commenter had only cited a 
portion of the full statement. When taken in its full context, the 
statement is highlighting that this new subsurface dispersant 
application approach is intended to reduce the risk of using excessive 
quantities of dispersants. The full statement recognizes that 
dispersing oil does not remove it from the environment and that in some 
instances subsurface dispersant use has the potential to increase 
exposures near the discharge. The Agency recognizes the inherent 
uncertainties with a subsurface application approach, which is an 
integral part of the basis for the new monitoring requirements in this 
final action. For pre-authorization of dispersant use requests, the 
final action does not prevent the RRT from establishing additional 
criteria to address incident-specific concerns beyond those 
requirements in the final rule, or from establishing incident-specific 
criteria for those situations not covered in the final rule. RRT 
authorities and responsibilities are set forth in the NCP and are 
outside the scope of this action.
    Some commenters further advocated making all monitoring results and 
information publicly available; some commenters suggested daily 
reporting and public notification protocols and that results of 
dispersant monitoring performed during the Deepwater Horizon oil spill 
response be released to provide an example of the types of information 
that can be obtained from existing methods and technologies.
    The final action includes requirements for the responsible party to 
provide reporting to the OSC, including daily reporting of the 
monitoring data results. EPA expects that daily reporting would be 
reflective of an operational schedule based upon a 24-hour time period. 
Further details of those requirements are found in the Immediate 
Reporting and Daily Reporting discussions in this preamble. Regarding 
public notification protocols, EPA notes that the OSC directs response 
efforts and coordinates all other efforts at the scene of a discharge, 
including public information and community relations. See 40 CFR 
300.120. The NCP provides instruction to the OSC on ensuring all 
appropriate public and private interests are kept informed and that 
their concerns are considered throughout a response. See 40 CFR 
300.155. The OSC public communications authorities under the NCP are 
outside the scope of this action. The Agency worked with Federal 
interagency partners in developing the 2013 NRT Environmental 
Monitoring for Atypical Dispersant Operations guidance, which includes 
examples of the types of information that can be obtained from relevant 
methods and technologies, and which serves as a basis for this action. 
Additionally, while the Agency did incorporate lessons learned from 
dispersant use operations during the Deepwater Horizon oil spill into 
this final action, the new monitoring requirements are performance 
based and focused on information requirements. The Agency

[[Page 40240]]

believes this approach provides the opportunity to consider relevant 
technologies and to capture advances in technologies.
    A commenter expressed concerns over proposed language that seems to 
suggest that EPA views comprehensive and quantitative monitoring of 
dispersant effectiveness at sea as a feasible proposition. This 
commenter stated that currently, this type of monitoring is not 
technically possible and suggested that the word ``comprehensive'' be 
replaced with the word ``adaptive'' throughout this section. The 
commenter noted that this change would allow decisions related to 
dispersant use to be revisited as circumstances surrounding the release 
change.
    The Agency disagrees that comprehensive and quantitative monitoring 
of dispersant effectiveness at sea is not currently technically 
possible. The requirements set forth in this action are informed by 
lessons learned during the Deepwater Horizon response and are 
consistent with the 2013 NRT Environmental Monitoring for Atypical 
Dispersant Operations guidance. Further, the Agency disagrees that the 
narrative describing the monitoring requirements should replace the 
term ``comprehensive'' with the term ``adaptive.'' The commenter stated 
that describing the monitoring requirements as ``adaptive'' would allow 
decisions related to dispersant use to be revisited as circumstances 
surrounding the release change. The Agency disagrees that 
characterizing the specific regulatory provisions in this action as 
comprehensive would in any way preclude the OSC to adapt operational 
decisions based on the monitoring data. The Agency is describing the 
new monitoring requirements as comprehensive because they go beyond the 
initial dispersant application to also include the transport and 
environmental effects of the dispersant and dispersed oil in the water 
column.
    A commenter requested that EPA provide additional supporting 
references for the proposed requirements. The commenter suggested that 
supporting references could include peer-reviewed articles published 
since 2012 that examine the use of dispersants during the Deepwater 
Horizon response or the 48 studies initiated by government agencies 
cited in a 2012 U.S. Government Accountability Office (GAO) report. 
They also suggested that reference be made to the 2011 Federal On-Scene 
Coordinator (FOSC) Deepwater Horizon Operational Science Advisory Team 
(OSAT) Report, which indicated that there were no identifiable harmful 
impacts to any marine life following dispersant applications. The 
commenter requested that new monitoring requirements for the dispersant 
use situations applicable to this action be reconsidered in the context 
of recent scientific research. A commenter requested EPA review recent 
publications that suggest the effectiveness of dispersant use, citing 
results from monitoring and testing during the Deepwater Horizon oil 
spill response. Further, a commenter stated that the new monitoring 
requirements are unnecessary until EPA can provide published results 
indicating harm from dispersant use to the environment or public 
health. Similarly, a commenter stated that if there is no intention to 
include recent research in the proposed update, the new requirements 
should not be promulgated.
    The Agency believes it has demonstrated the need for these new 
monitoring requirements to inform operational decision-making specific 
to atypical dispersant use. As already highlighted, the new 
requirements are consistent with the 2013 NRT Environmental Monitoring 
for Atypical Dispersant Operations guidance, which addresses the 
dispersant use situations addressed by this action. Further, the Agency 
disagrees that recent scientific research would necessitate 
reconsidering the minimum set of monitoring requirements for the 
atypical dispersant use situations as specified in this action. EPA 
recognizes uncertainties still surrounding dispersant use, particularly 
for the atypical dispersant use situations contemplated since their use 
during the Deepwater Horizon oil spill. EPA continues to participate in 
scientific efforts with scientists and researchers from industry, 
academia, and public organizations, such as the multi-year State-of-
the-Science for Dispersant Use in Arctic Waters effort sponsored by 
NOAA though the Coastal Response Research Center, which continue to 
identify unknowns and uncertainties relative to this response 
technology. EPA also continues to actively participate as a standing 
member of the Interagency Coordinating Committee on Oil Pollution 
Research (ICCOPR), a 15-member Interagency Committee established by 
Title VII of the Oil Pollution Act of 1990 (Section 7001). EPA's own 
research efforts and on-going engagement with the broader research 
community support the need for the new monitoring provisions 
established in this final action. Finally, the Agency notes the 
commenter's request to recognize the 2011 Deepwater Horizon OSAT 
Report. The commenter did not specify which 2011 OSAT report. The 
February 10, 2011, OSAT report is a summary for fate and effects of 
remnant oil in the beach environment. The July 8, 2011, report is an 
ecotoxicity addendum entitled ``Summary Report for Sub-Sea and Sub-
Surface Oil and Dispersant Detection: Ecotoxicity Addendum.'' EPA's 
understanding is that the OSAT reports focused on information to guide 
response actions and do not draw conclusions about long-term 
environmental impacts of the spilled oil. Specifically, the OSAT 
ecotoxicity addendum report states that its purpose was to provide the 
OSC with information on the remaining toxicity of released oil and 
dispersant to representative water column and sediment-dwelling 
organisms at the time the samples were collected and intended to inform 
the OSC regarding transition of nearshore activities from the emergency 
response phase to the long-term recovery and restoration phase. The new 
monitoring requirements promulgated in this action will serve to inform 
dispersant use decisions during a response by providing environmentally 
relevant data and information to the OSC and other Agencies with roles 
and responsibilities under the NCP where atypical dispersants are 
deployed. Under the NCP, the OSC directs the response consistent with 
provisions including 40 CFR 300.120, 40 CFR 300.150, and Subpart D, 
which includes threats to the public health.
    The Agency acknowledges that scientific research continues 
regarding dispersant use in general and with respect to the Deepwater 
Horizon oil spill. The Agency disagrees with the commenter that the 
monitoring requirements should be removed because EPA did not include 
references that the commenter characterized as the numerous scientific, 
peer-reviewed publications published since May 2012 in the 2015 
preamble that the commenter stated to have examined the dispersant use 
during DWH. The commenter did not provide a list of references or 
examples as illustrations, nor included those that may be relevant to 
the monitoring provisions. The Agency believes that the new monitoring 
requirements will provide information and data to inform future 
response decisions for atypical dispersant use situations reflective of 
the Deepwater Horizon oil spill-type and other scenarios. Furthermore, 
these new monitoring requirements will provide information and data 
that address knowledge gaps identified in

[[Page 40241]]

the 2012 GAO report, ``U.S. Government Accountability Office Report, 
Oil Dispersants, Additional Research Needed, Particularly on Subsurface 
and Arctic Applications,'' which commenters also referenced.
    The Clean Water Act provides that the National Contingency Plan 
``shall include, but not be limited to, the following: . . . (F) 
Procedures and techniques to be employed in identifying, containing, 
dispersing, and removing oil and hazardous substances. (G) A schedule, 
prepared in cooperation with the States, identifying--(i) dispersants, 
other chemicals, and other spill mitigating devices and substances, if 
any, that may be used in carrying out the [NCP], (ii) the waters in 
which such dispersants, other chemicals, and other spill mitigating 
device and substances may be used, and (iii) the quantities of such 
dispersant, other chemicals, or other spill mitigating device or 
substance which can be used safely in such waters . . . .'' In 
conjunction with the existing testing requirements, listing of agents, 
and authorization of use procedures, the promulgation of these new 
monitoring requirements provide data which can be used to inform the 
decision making of the OSC and of the other Agencies with roles and 
responsibilities under the NCP. The wide variability in waters, weather 
conditions, organisms living in the waters, and types of oil that might 
be discharged requires this combined approach.
    A commenter expressed concerns that in the event of a spill these 
new monitoring requirements may hamper response activities from 
occurring in a timely manner. They recommended that effectiveness 
monitoring be conducted as a set of tabletop exercises first, to 
determine whether the monitoring protocols are feasible. This commenter 
also requested recognition for other analytical options such as in-situ 
analytical techniques.
    The Agency disagrees with the premise that monitoring requirements 
could hamper response activities from occurring in a timely manner. The 
Agency notes the time frame for the deployment of subsurface dispersant 
injection equipment by vessels for offshore facilities is not expected 
to be different than the time frame for deploying monitoring equipment. 
Monitoring requirements should not delay or impede response actions 
related to the deployment of mechanical recovery, in-situ burning, or 
dispersant-related equipment. The monitoring and data submissions that 
serve as the basis of this rule were established in the 2013 NRT 
Environmental Monitoring for Atypical Dispersant Operations guidance 
document. The Agency is aware that industry and OSROs have been 
preparing for the requirements of this rule since the 2013 interagency 
signing of the NRT guidance document. This final action provides notice 
for a potential responsible party to identify and prepare for 
deployment of monitoring assets including identifying response 
personnel, equipment, and sampling materials. Potential responsible 
parties also have time to identify and plan for the need of alternative 
resources to account for events such as equipment failure, rather than 
wait until an incident occurs. The Agency encourages the continuation 
of planning and preparedness efforts and continues to support these 
efforts with our interagency partners.
    A commenter indicated that monitoring of dispersants in the coastal 
zone should be under the authority of the United States Coast Guard 
(USCG). This commenter suggested that the RRT and OSC should have 
decision-making authority as indicated in NRT's Environmental 
Monitoring for Atypical Dispersant Operations and the SMART document. 
Another commenter stated that this section of the proposed rule should 
be consistent with, and pose no conflict to, the NRT guidance found in 
the 2013 Environmental Monitoring for Atypical Dispersant Operations 
document.
    The Agency recognizes OSC roles, responsibilities and authorities 
as described in the NCP, including USCG OSC roles and responsibilities 
in the coastal zone as described in 40 CFR 300.120 and Sec.  300.140. 
EPA has responsibilities under Subpart J of the NCP that apply to the 
use of chemical agents in the coastal and inland zones, including an 
authorization of use role as provided in 40 CFR 300.910 (states and 
other federal agencies also have responsibilities under this 
provision). The Agency acknowledges that the atypical dispersant use 
situations subject to the new monitoring requirements will likely be 
overseen by a USCG OSC. The President has delegated EPA the authority 
under CWA 311(d) to revise or otherwise amend the NCP and to establish 
requirements for dispersants, other chemicals, and other spill 
mitigating devices and substances, which are found in Subpart J of the 
NCP. The Agency has structured the amendments to Subpart J of the NCP 
to include not only the testing and listing protocols, and the 
authorization of use procedures, but also the monitoring provisions to 
ensure agents are being used appropriately. The new monitoring 
requirements are consistent with existing RRT and OSC authorities and 
responsibilities under the NCP. Finally, the requirements set forth in 
this action are informed by lessons learned during the Deepwater 
Horizon oil spill and are consistent with the 2013 NRT Environmental 
Monitoring for Atypical Dispersant Operations guidance.
    The Agency acknowledges the recommendation to renumber the 
monitoring section but is not making this change because the numerical 
order of the provisions has no practical effect on the regulatory 
requirements.
2. Roles and Responsibilities for Monitoring Operations
    Several commenters expressed concern specific to the requirements 
for the responsible party to monitor the use of dispersants under the 
direction of the OSC. A commenter stated that the responsible party 
should not oversee monitoring for impacts related to the spill for 
which they are responsible. Similarly, other commenters suggested the 
OSC select a qualified third party to be responsible for monitoring and 
water column testing processes during the response instead of the 
responsible party. Further, the commenters stated that the third party 
should be required to disclose any relationship with the responsible 
party to avoid potential conflicts of interest and suggested that the 
OSC oversee transparency in the monitoring and water quality testing 
processes. Commenters suggested that this third-party monitor should be 
acceptable to the OSC, EPA, Department of Interior (DOI) RRT 
representatives (potentially including DOC RRTs), as well as the 
responsible party. A commenter also suggested that because the QAPP 
will include DOI trust resources, it should be submitted and approved 
by DOI RRT representatives and the OSC. Commenters also suggest adding 
a timeline for submission and approval of the QAPP documentation.
    EPA recognizes commenters' concerns regarding the responsible party 
conducting dispersant monitoring due to inherent conflicts of interest. 
The Agency notes that under the NCP the OSC coordinates, directs and 
reviews the work of the responsible party. See, e.g., 40 CFR 300.120. 
The Agency believes the responsible party must be prepared for and 
provide resources to gather data and information to inform decisions 
regarding dispersant use operations. The approach to this final action 
is consistent with the NCP response framework, taking advantage of the 
knowledge and geographic proximity of the responsible party as 
applicable, and allowing for the effective allocation of limited

[[Page 40242]]

governmental resources. Additionally, the new monitoring requirements 
in this final action do not, for example, preclude the OSC from seeking 
a qualified third party to conduct additional monitoring or testing, 
from requiring the responsible party to use a third party to conduct 
the monitoring or testing where the OSC deems it appropriate, or from 
seeking supplemental data and information separately. Similarly, the 
final rule does not preclude the consideration of third-party testing 
or test results.
    The Agency notes that the NCP already provides for the natural 
resource trustees' roles relative to dispersant use. Further, this 
final rule does not amend any regulatory requirements or authorities, 
including EPA-delegated authorities under Subpart J, or regarding the 
OSC role to direct public and private spill response efforts, the Area 
Committee responsibilities for developing Area Contingency Plans, or 
the responsible party's obligations for preparing Facility or Vessel 
Response Plans, as applicable. The NCP establishes the Regional 
Response Teams and their roles and responsibilities in the National 
Response System, including coordinating preparedness, planning, and 
response at the regional level. Nothing in this final action precludes 
OSC consideration of local interests and knowledge for effective 
allocation of resources, nor interferes with NCP established roles and 
responsibilities for response actions. The DMQAPP developed by the 
responsible party will be submitted to the OSC to provide context and 
allow for better understanding of monitoring data and information. The 
OSC has not only the expertise of the SSC available to assist with the 
data collected following the DMQAPP, it also has available within the 
existing NCP authorities the expertise of the respective state (as 
applicable), DOI RRT representatives and other pertinent agencies. The 
NCP designates the RRT as the appropriate regional mechanism for 
coordination of assistance and advice to the OSC during such response 
actions. As specified in the final regulatory text, the responsible 
party must submit a DMQAPP to the OSC covering the collection of 
environmental data within this section as part of implementing the 
monitoring requirements. The Agency again encourages planning and 
preparedness efforts and continues to support these efforts with our 
interagency partners.
    A commenter suggested that although the proposed rule requires the 
responsible party to conduct monitoring, these operations would be 
completed under the direction of the OSC. The commenter indicated that 
the NCP provides for a three-tiered approach, including the Federal 
government directing all public and private spill response efforts for 
certain types of spill events; Area Committees developing detailed, 
location-specific Area Contingency Plans; and vessel and certain 
facility owners and operators preparing Facility Response Plans. The 
commenter suggested that this type of tiered approach allows for 
Federal oversight without dismissing local interests and knowledge and 
enables the efficient allocation of limited resources for response 
actions.
    The Agency agrees that the USCG OSC generally oversees the 
responsible party during coastal zone response operations, which 
includes implementation of the new monitoring requirements. The new 
monitoring requirements fall within the existing NCP framework of 
federal government oversight through the OSC. The NCP serves as the 
federal government's blueprint for responding to oil discharges or 
threats of discharge, ensuring national response capabilities and 
promoting coordination among the hierarchy of responders and 
contingency plans. The approach to this final action is consistent with 
the NCP response framework, taking advantage of the knowledge and 
geographic proximity of the responsible party as applicable, and 
allowing for the effective allocation of limited governmental 
resources. These new provisions of minimal monitoring requirements 
under Subpart J for specific atypical dispersant use situations are 
consistent with the existing NCP authorities and objectives.
    A commenter suggested that monitoring be required as directed by 
the OSC. The commenter suggested that every response is unique in terms 
of the type of spill and appropriate actions, and therefore, discretion 
should be given to the OSC to determine monitoring requirements. This 
commenter indicated that any monitoring requirements should be 
consistent with the phased approach to monitoring that is discussed in 
the SMART protocols. The commenter also pointed out that USCG Strike 
Teams have monitoring requirements and asked EPA for clarification 
related to the reasoning behind changing the existing monitoring 
process and oversight structure.
    The Agency agrees discretion needs to be afforded to the OSC to 
account for incident- specific circumstances in a response. This action 
specifies that the new monitoring requirements are to be implemented by 
the responsible party. The Agency notes that under the NCP the OSC has 
an established oversight role over the responsible party; the OSC 
continues to have authority to direct additional monitoring and data 
collection beyond that which is specified in the new requirements. This 
may include local field efficacy testing prior to dispersant use to 
better understand and account for site specific conditions in 
operational decision-making. While the SMART protocols may be utilized 
not only in pre-deployment field testing but also as part of the 
overall response, the atypical uses of dispersant during a response 
that are addressed in this action were neither envisioned nor addressed 
in the existing SMART monitoring program. The requirements in this 
final action follow recommendations from the Environmental Monitoring 
for Atypical Dispersant Operations developed by NRT member agency 
representatives in 2013. The 2013 NRT guidance focuses on monitoring 
atypical use of dispersants during an oil discharge in order to provide 
data that will inform decision-making for dispersant use operations in 
a response. Further discussion on SMART protocols can be found in the 
Field monitoring to support operational decisions discussion in this 
preamble.
    The Agency recognizes OSC roles, responsibilities, and authorities 
as described in the NCP, including USCG OSC roles and responsibilities 
in the coastal zone as described in 40 CFR 300.120 and 300.140, with 
additional clarification provided in previous Federal Register notices 
(e.g., 59 FR 47389). EPA has responsibilities under Subpart J of the 
NCP that apply to the use of chemical agents in both the coastal and 
inland zones, including an authorization of use role as provided in 40 
CFR 300.910 (states and other federal agencies also have 
responsibilities under this provision). The Agency acknowledges that 
the atypical dispersant use situations subject to the new monitoring 
requirements will likely be overseen by a USCG OSC. The President has 
delegated EPA the authority under CWA 311(d) to revise or otherwise 
amend the NCP and to establish requirements for dispersants and other 
chemicals, and other spill mitigating devices and substances, which are 
found in Subpart J of the NCP. The Agency has structured the amendments 
to Subpart J of the NCP to include the testing and listing protocols, 
the authorization of use procedures, and the monitoring provisions to 
ensure agents are being used appropriately. The

[[Page 40243]]

new monitoring requirements are consistent with existing RRT and OSC 
authorities and responsibilities under the NCP. Finally, EPA is unaware 
of any regulatory requirements issued by the USCG Strike Teams 
regarding dispersant use monitoring.
3. Field Monitoring To Support Operational Decisions
    Several commenters expressed concerns that the proposal does not 
effectively justify the additional monitoring requirements. These 
commenters believe the additional monitoring requirements could cause 
delays in response actions, preclude dispersant use, and result in 
additional environmental damages. Some commenters expressed concerns 
that the proposed rule may hinder timely response operations, as 
opposed to improve real-time decision-making. They suggested the 
monitoring requirements should be designed by the OSC to fit the needs 
of the given environment.
    The Agency disagrees with the premise that monitoring requirements 
could hamper response activities from occurring in a timely manner. The 
Agency notes the time frame for the deployment of subsurface dispersant 
injection equipment by vessels for offshore facilities is not expected 
to be different than the time frame for deploying monitoring equipment. 
The Agency reiterates the new monitoring provisions do not change 
current preparedness or planning regulatory requirements; the 
monitoring and data submissions that serve as the basis of this rule 
were established in the 2013 NRT Environmental Monitoring for Atypical 
Dispersant Operations document. The Agency is also aware that industry 
and OSROs have been preparing for the requirements of this rule since 
the 2013 interagency signing of the referenced NRT guidance document. 
This final action provides notice for a potential responsible party to 
identify and prepare for deployment of monitoring assets including 
identifying response personnel, equipment, and sampling materials. 
Potential responsible parties also have time to identify and plan for 
the need of alternative resources to account for events such as 
equipment failure, rather than wait until an incident occurs. The 
Agency encourages the continuation of planning and preparedness efforts 
and continues to support these efforts with our interagency partners. 
Additionally, monitoring requirements should not delay or impede 
response actions related to the deployment of mechanical recovery, in-
situ burning, or dispersant-related equipment.
    Other commenters added that the proposed requirements deviate 
significantly from existing monitoring regimes from the NRT in its 
Environmental Monitoring for Atypical Dispersant Operations, which the 
commenters characterized as advocating for the adaptation of the SMART 
monitoring regimen. Some commenters requested that EPA adjust the 
language to require SMART Tier I efficacy monitoring for the first use 
of dispersants, followed by environmental impact monitoring no later 
than 96 hours after the first application.
    Some commenters also suggested that the proposed rule goes beyond 
what is required by the NRDA. These commenters also stated that the new 
requirements appear to focus on the environmental effects of dispersant 
use rather than the health and safety of response workers. One 
commenter asked EPA to clarify that the primary objective of 
characterizing the efficacy of response agents is to protect response 
personnel health and safety. The commenters also suggested the OSC 
employ the Net Environmental Benefits Analysis (NEBA) structure to 
assess the overall benefits of dispersant use. Another commenter 
expressed concern about this type of monitoring informing response 
decision-making. Other commenters requested that EPA clarify between 
short-term monitoring result that must be disseminated extremely 
quickly and those that are part of a more comprehensive longer-term 
monitoring process.
    The new monitoring section is modeled after the 2013 NRT guidance 
document, Environmental Monitoring for Atypical Dispersant Operations, 
developed following the Deepwater Horizon oil spill and tailored to 
monitoring atypical dispersant use situations. These NRT guidelines 
specified that atypical use of dispersants during a response are not 
addressed in the existing SMART monitoring program. In addition to the 
criteria outlined in the NRT guidelines, the Agency included 
applicability criteria for the new monitoring requirements for 
situations where the surface use of dispersants is authorized in 
response to oil discharges of more than 100,000 U.S. gallons occurring 
within a 24-hour period. The Agency chose 100,000 U.S. gallons as a 
threshold criterion based on the NCP classification of major discharges 
to coastal waters. EPA combined this 100,000 U.S. gallons major 
discharge criterion with a 24-hour time frame, considering that a 
larger quantity of dispersant may be required in a short time frame for 
an incident of this scale. The applicability criteria in the final rule 
are consistent with the NRT Environmental Monitoring for Atypical 
Dispersant Operations guidelines.
    As noted in the proposed rule, the goal of establishing a Schedule 
under the NCP is to protect the environment from potential damage 
related to spill mitigating products used in response to oil 
discharges. This goal is consistent with past preambles related to 
Subpart J. For example, the 1994 NCP final rule (59 FR 47407) noted, 
``. . . EPA believes that Congress' primary intent in regulating 
products under the NCP Product Schedule is to protect the environment 
from possible deleterious effects caused by the application or use of 
these products. In looking at the long- and short-term effects on the 
environment of all spill mitigating devices and substances, EPA has 
concluded that chemical and bioremediation countermeasures pose the 
greatest threat for causing deleterious effects on the environment.'' 
While EPA recognizes that worker health and safety are integral to any 
oil spill response, provisions for these specific concerns are found 
under 40 CFR 300.150 of the NCP and are outside the scope of this 
action.
    EPA disagrees with commenters that the new provisions should 
require SMART Tier I efficacy monitoring for the first use of 
dispersants, followed by environmental impact monitoring no later than 
96 hours after the first application. While EPA recognizes the 
application of SMART Tier I protocols for evaluating initial dispersant 
efficacy, these protocols are based on aerial visual assessments by 
trained observers or advanced remote sensing instruments flying over 
the oil slick. To help evaluate visual assessments, NOAA developed a 
Dispersant Application Observer Job Aid, which is a field guide for 
trained observers to promote consistency in identification of dispersed 
and undispersed oil, describing oil characteristics, and reporting this 
information to decision-makers. The SMART protocols recognize that 
visual observations do not always provide confirmation that the oil is 
dispersed, and that dispersant operations effectiveness can be 
difficult to determine by visual observation alone.
    The SMART protocols do not monitor the fate, effects, or impacts of 
dispersed oil. The monitoring of atypical dispersant use necessitates 
specific considerations beyond those addressed by SMART. The 2013 NRT 
Environmental Monitoring for Atypical

[[Page 40244]]

Dispersant Operations recognizes such atypical uses of dispersant 
during a response are not addressed in the existing SMART monitoring 
program. Further, the SMART protocols do not apply to any subsurface 
dispersant application. EPA is unaware of any similar NRT-approved 
protocols or NOAA-developed job aids related to subsurface dispersant 
application. The new monitoring requirements in this final action are 
intended to supplement, not to replace, the SMART protocols. The new 
requirements recognize that SMART monitoring protocols are expected to 
have already been deployed in atypical dispersant use situations. While 
some monitoring requirements are included in the SMART Tier III 
protocol (e.g., turbidity, pH, Conductivity, Temperature), other 
requirements important to the understanding of dispersant effectiveness 
(e.g., in situ droplet size distribution) are not.
    A commenter noted that this action may be an opportunity to broaden 
the proposed requirements to cover all response approaches. Other 
commenters also suggested the RRT should have the ability to require 
field testing of a given approach prior to response action approval. A 
commenter expressed that this type of monitoring does inform response 
decision-making; the commenter requested that EPA clarify between 
short-term monitoring results that must be disseminated extremely 
quickly and those that are part of a more comprehensive longer-term 
monitoring process.
    While this action specifically addresses certain atypical 
dispersant use operations, the Agency notes the OSC continues to have 
authority to direct additional monitoring and data collection beyond 
that which is set forth in the new monitoring requirements. Under the 
NCP, the OSC has the authority to direct monitoring and data collection 
for any and all approaches utilized during a response. This may include 
field efficacy testing prior to dispersant use to better understand and 
account for site-specific conditions in operational decision-making. 
RRT authorities and responsibilities are set forth in the NCP and are 
outside the scope of this action. However, for pre-authorization of 
dispersant use requests, the Agency notes that this final action does 
not prevent a RRT from establishing additional criteria to address 
incident-specific concerns beyond those requirements in the final rule, 
or from establishing incident-specific criteria for those situations 
not covered in the final rule.
    Dispersants are not the only option for oil spill response, as 
other mitigation options are available that may lower the potential 
overall environmental damage. Decisions to use dispersants and other 
chemical agents used during a response are to be made in accordance 
with Subpart J of the NCP and all applicable statutes. Any 
environmental tradeoff methodologies for oil spill responses where 
dispersants and other chemical agents are considered must be in 
conformance with the statutory and regulatory authorities that govern 
their use.
4. Criteria for Triggering Monitoring Requirements
    EPA received comments specific to the proposed thresholds or 
applicability criteria for triggering the monitoring requirements. A 
commenter indicated that although they agree with EPA's proposal to 
include thresholds above which monitoring requirements would apply, 
they suggested that the spill rate and volume be reduced. The commenter 
recommended that the trigger applicability volume threshold for 
monitoring be set to a discharge of more than 50,000 U.S. gallons 
within 24 hours and surface use of dispersants for more than 48 hours. 
Another recommended a lower release threshold of 21,000 gallons (500 
barrels), and any dispersant use lasting more than 24 hours. In 
contrast, other commenters requested further clarification, and yet 
others a more relaxed set of thresholds for comprehensive monitoring. A 
commenter suggested that the proposed release volume of 100,000 gallons 
be relaxed, stating there are other factors to consider that influence 
spill outcomes beyond the spill volume. Commenters also expressed 
concern regarding the 96-hour duration threshold requirement for 
dispersant use and suggested that especially for earlier life stages 
near the surface, a 96-hour exposure has the potential for adverse 
effects. Citing the information above, a commenter proposed a 24-hour 
threshold for comprehensive monitoring instead of 96 hours. Finally, a 
commenter asked for clarification on the requirements for monitoring of 
dispersants use when the spill volume is less than 100,000 gallons in 
the first 24 hours or for dispersant use occurring over a period of 
less than 96 hours.
    The Agency received support for establishing monitoring 
requirements, with commenters also offering opposing perspectives on 
the applicability thresholds that would trigger these requirements. The 
Agency agrees with the concept of monitoring the use of all chemical 
agents during a response; however, the monitoring requirements in this 
action apply specifically to certain atypical dispersant use 
situations. The Agency acknowledges some commenters' support for the 
new monitoring requirements applying to any subsurface dispersant use 
in a response. The Agency considered the alternative threshold and 
applicability criteria some commenters offered for atypical surface 
dispersant uses: 50,000 or 21,000 U.S. gallons within a 24-hour period 
and surface use of dispersants for more than 48 or 24 hours. Another 
commenter suggested that any enhanced monitoring beyond that required 
in the SMART protocols should commence within seven days. However, EPA 
disagrees with revising the proposed applicability thresholds for 
surface dispersant use, including those commenters who requested a more 
relaxed set of thresholds for the proposed discharge volume of 100,000 
U.S. gallons.
    While modeled after the 2013 NRT guidance, the Agency included the 
additional applicability criterion for the new monitoring requirements 
for situations where the surface use of dispersants is authorized in 
response to oil discharges of more than 100,000 U.S. gallons occurring 
within a 24-hour period. The Agency chose 100,000 U.S. gallons as a 
threshold criterion based on the NCP classification of major discharges 
to coastal waters. EPA combined this 100,000 U.S. gallons major 
discharge criterion with a 24hour time frame, considering that a larger 
quantity of dispersant may be required in a short time frame for an 
incident of this scale. The Agency believes the potential variability 
in response actions for an incident of this magnitude, including 
consideration of the time needed for deployment, merits this scenario 
being included as a trigger for applicability of the new monitoring 
requirement.
    The Agency recognizes that especially for earlier life stages near 
the surface, a longer exposure time frame has the potential for adverse 
effects. The 96-hour time frame in this action is based on 96 hours 
being a common exposure duration used in toxicological studies of 
dispersants. While recognizing that the 24- and 48-hour time frames may 
also be used in toxicological studies, the Agency's intent in proposing 
these specific monitoring requirements was to have them apply to 
atypical spill situations with the potential for larger amounts of 
dispersants being used. The Agency also disagrees with relaxing the 
time frame for the new requirements to begin monitoring within seven 
days, as the upper limit of that time frame would

[[Page 40245]]

be outside what the NRT has recognized as an atypical surface 
dispersant use situation. The Agency continues to believe that the 
applicability thresholds for both the quantities and durations for 
surface dispersant use as proposed serve to capture the potential for 
the broader ecosystem impacts resulting from the larger spills that are 
the focus of the new monitoring requirements. Finally, the 
applicability criteria in the final rule are consistent with NRT 
Environmental Monitoring for Atypical Dispersant Operations guidelines.
    A commenter indicated that the phrase ``upon initiation and for the 
duration of subsurface dispersant use'' can be misconstrued to mean 
that monitoring should be conducted at all times. They suggested that 
monitoring requirements be determined by the OSC given the potential 
variability in response actions. This would allow the OSC to determine 
the best timing for operational monitoring deployment. This commenter 
also stated that the volume and duration criteria for monitoring should 
be replaced with a single criterion that ``any enhanced monitoring 
beyond SMART shall commence within seven days.'' According to the 
commenter, this ensures that the best experts can be mobilized to 
respond to the spill, monitoring vessels can be located and mobilized, 
sampling strategies can be developed, and appropriate safety 
considerations can be reviewed.
    EPA proposed new monitoring requirements for the responsible party 
to implement when any subsurface and certain surface dispersant use 
conditions are met: ``When these dispersant use conditions are met, and 
for the duration of dispersant operations, the responsible party shall 
. . .''. EPA disagrees that the phrase can be misconstrued when taken 
within the context of the new monitoring requirements because it is 
qualified with the statement: ``When these dispersant use conditions 
are met . . .''. Further, the new minimum set of requirements for the 
specified atypical dispersant use conditions fall within the construct 
of the NCP and do not prevent the OSC to further consider the potential 
variability for any given response action. Additionally, the 
responsible party is required to submit a DMQAPP to the OSC, in which 
some of the incident-specific considerations to implementing monitoring 
operations can be addressed while still meeting the regulatory 
provisions. Thus, the Agency disagrees that the new provisions may not 
offer enough flexibility to allow for an appropriate level of 
monitoring.
    As stated before, the final rule provides notification for a 
responsible party to identify and prepare for potential deployment of 
monitoring assets prior to the incident. Monitoring assets for a 
responsible party to identify and prepare for include response 
personnel, equipment, sampling materials, and alternative resources to 
account for equipment failure. The Agency also considered the steps 
taken for the deployment of subsurface dispersant injection equipment, 
including their associated time frames. The Agency does not believe 
deploying monitoring equipment should take longer than the deployment 
of subsurface dispersant injection equipment. Replacing the 
applicability criteria with a single criterion that ``any enhanced 
monitoring beyond SMART shall commence within seven days'' would result 
in subsurface dispersant application without any subsurface monitoring 
in place or surface monitoring beyond the intended applicability of 
SMART.
    Some commenters were against having thresholds or applicability 
criteria for triggering the monitoring requirements and suggested that 
EPA should require comprehensive monitoring in all instances of 
dispersant or any other product use, regardless of the spill volume or 
duration, especially in Arctic waters. Some commenters asserted that 
this type of comprehensive monitoring would better capture acute 
effects on aquatic organisms. Other asserted comprehensive monitoring 
is important as it may represent the only opportunity to test the 
efficacy of these agents in a field or ``real world'' setting.
    The Agency recognizes that there may be other factors to consider 
that influence spill outcomes beyond the spill volume. Further, surface 
dispersant use situations outside those specifically covered by the 
applicability criteria established in this final rule may also have 
adverse impacts. Thus, there is value in conducting operational 
monitoring for all instances of dispersant or any other chemical agent 
use, regardless of the spill volume, duration, or affected ecosystem. 
The new monitoring requirements in this action do not preclude an OSC 
from directing the responsible party to adopt similar procedures for 
dispersant use situations not covered by the established applicability 
criteria. This action does not impact the OSC authority to direct any 
monitoring necessary to evaluate dispersant efficacy and address 
potential toxicity concerns on aquatic organisms specific to the 
response, including in remote settings such as Arctic waters.
    A commenter suggested the use of SMART Tier I monitoring protocols 
for all surface dispersant use and monitoring of long-term effects of 
dispersant use specific to a particular incident. Another suggested 
that efficacy monitoring should follow the SMART Tier I, Tier II, and 
Tier III protocols. Some commenters also suggested that monitoring 
information can be used to verify planning assumptions and also to 
support seafood safety decisions and NRDA activities. A commenter 
suggested the proposed rule may not offer enough flexibility to allow 
for an appropriate level of monitoring and requested that EPA revise 
the requirements to allow for OSC and RRT assessments of monitoring 
needs at each site instead of on a discharge volume basis.
    The Agency disagrees with extending these new specific requirements 
to all instances of dispersant use. However, it agrees in part with 
commenters that dispersant use should be monitored and that monitoring 
of discharges not meeting the thresholds for these atypical monitoring 
requirements should, at a minimum, follow the NRT-approved SMART Tier 
I, Tier II, and Tier III protocols. EPA notes that RRTs typically 
include SMART monitoring as an essential element in their authorization 
of use review which is implemented during a response EPA disagrees with 
commenters who stated that all surface dispersant use should use the 
SMART Tier I protocol. While EPA recognizes the value of the SMART Tier 
I protocol in evaluating initial dispersant efficacy, it is based on 
aerial visual assessments by trained observers or advanced remote 
sensing instruments flying over the oil slick. To help evaluate visual 
assessments, NOAA developed a Dispersant Application Observer Job Aid, 
which is a field guide for trained observers to promote consistency in 
identification of dispersed and undispersed oil, describing oil 
characteristics, and reporting this information to decision-makers. The 
SMART Tier I protocol recognizes visual observations do not always 
provide confirmation that the oil is dispersed, and that dispersant 
operations effectiveness can be difficult to determine by visual 
observation alone. The SMART protocols do not monitor the fate, 
effects, or impacts of dispersed oil.
    The monitoring of atypical dispersant use necessitates specific 
considerations beyond those addressed by the SMART protocols. The new 
monitoring section in this rule is modeled after the 2013 NRT guidance 
document Environmental Monitoring for Atypical Dispersant

[[Page 40246]]

Operations, developed following the Deepwater Horizon oil spill and 
specifically tailored to the type of atypical dispersant use situations 
covered by these new requirements. The 2013 NRT guidelines specify that 
atypical uses of dispersants during a response are not addressed in the 
existing SMART monitoring protocols. Again, the SMART protocols do not 
apply to subsurface dispersant applications. EPA is unaware of any 
similar NRT-approved protocols or NOAA-developed job aids related to 
subsurface dispersant application. The new monitoring requirements in 
this final action are intended to supplement, and not to replace, the 
SMART protocols. The new requirements take into account that the SMART 
monitoring activities are expected to have already been deployed in 
atypical dispersant use situations. While some monitoring requirements 
are included in the SMART Tier III protocol (e.g., turbidity, pH, 
Conductivity, Temperature), other requirements (e.g., in-situ droplet 
size distribution) that are important to the understanding of 
dispersant effectiveness are not.
    With respect to a commenter who recommended monitoring of long-term 
effects of dispersant use specific to a particular incident, the Agency 
agrees that potential long-term effects of dispersant use should be 
considered during dispersant use decision-making. However, monitoring 
the long-term effects of dispersant use specific to a particular 
incident is part of the NRDA process. Again, these new monitoring 
requirements are intended to inform operational decision-making 
specific to atypical dispersant use and not intended to be part of the 
NRDA. The broader NRDA data gathering efforts may apply to dispersant 
operations or other parts of the response.
    Some commenters stated that the efficacy of dispersants in Arctic 
waters is poorly understood and until additional scientific data is 
available, monitoring following any dispersant use should be required. 
A commenter suggested that in addition to the monitoring requirements, 
EPA should establish thresholds for the maximum dispersant application 
volumes over time, after which dispersants use should be ceased. 
Another suggested that all dispersant use should be curtailed until 
there is a more robust understanding of the toxic effects of these 
types of chemicals. Another commenter suggested that EPA should require 
site-specific testing and monitoring of products to determine efficacy 
prior to, during, and after response actions.
    The Agency disagrees with the comments that the new monitoring 
requirements should include thresholds for maximum dispersant 
application volumes over time, after which dispersants use should be 
ceased. Establishing dispersant use volumes depends not only on 
incident-specific factors, but also on many site-specific factors 
(e.g., local hydrodynamic conditions, species sensitivities), making 
this suggested approach overly restrictive. However, the Agency shares 
the commenters' concerns regarding the impact of atypical use of 
dispersants on the affected environments. The decision not to establish 
maximum dispersant application volumes over time, as part of these new 
monitoring requirements, should not be interpreted to mean that the 
Agency supports unlimited dispersant use. When responding under the 
NCP, decisions on dispersants and other chemical agents used are to be 
made in accordance with the authorization of use procedures in 40 CFR 
300.910 of Subpart J. The provisions under Subpart J are driven by the 
statutory requirement to develop a schedule (see CWA 311(d)(2)(G)) that 
identifies the waters and quantities in which dispersants and other 
chemical agents may be safely used in such waters. The OSC is to make 
dispersant use determinations for each response based on all relevant 
circumstances and in accordance with existing authorization of use 
procedures under Subpart J of the NCP. The data and information 
resulting from the new monitoring requirements promulgated in this 
action will serve to inform dispersant use decisions during a response 
by the OSC and other Agencies with roles and responsibilities under the 
NCP where atypical dispersants are deployed. The new monitoring 
provisions, when taken together with the existing testing requirements, 
listing of agents, and authorization of use procedures under Subpart J 
address the types of waters and the quantities of listed agents that 
may be used safely in such waters in a response. The wide variability 
in waters, weather conditions, organisms living in the waters, and 
types of oil that might be discharged requires this approach. Any 
environmental tradeoff methodologies applied to dispersant use 
decisions must be in conformance with the statutory and regulatory 
authorities that govern the dispersant use.
    The Agency continues to engage with the research community to 
incorporate advances in scientific understandings of dispersant use 
into existing policies. Curtailing all dispersant use until every 
aspect of dispersant efficacy and toxicity is studied would be 
impracticable and overly restrictive. However, EPA agrees an important 
aspect of dispersant use decision-making is documenting information and 
associated uncertainties of dispersant efficacy and toxicity specific 
to the conditions and geographical location where they are intended for 
use. The final monitoring requirements direct the responsible party to 
document the dispersant used and the rationale for dispersant 
choice(s), including the results of any efficacy and toxicity tests. 
Documentation of any additional efficacy and toxicity testing results, 
data or information specific to the area or site conditions, and 
associated uncertainties will assist the OSC and RRT(s) in choosing the 
appropriate dispersant use approach. The listing of a specific 
dispersant (i.e., dispersant product) on the NCP Product Schedule is 
not a rationale to use a dispersant in any given situation. Further, 
the listing of a specific dispersant on the NCP Product Schedule does 
not mean that EPA approves, recommends, licenses, certifies, or 
authorizes its use on an oil discharge. The listing means only that the 
required data have been submitted to EPA as required by Subpart J of 
the National Contingency Plan, 40 CFR 300.915.
    Finally, EPA agrees with commenters who requested the new 
monitoring requirements also include site-specific baseline monitoring 
prior to application of dispersant and is amending the final rule to 
reflect this change. The Agency believes this a rational and necessary 
addition since an understanding of baseline conditions is required for 
understanding the effects of dispersants in a specific area. The Agency 
believes that baseline monitoring will provide pre- and post- 
dispersant application data to better evaluate the effects, including 
physical dispersion, of the dispersants. Further discussion on this 
change to the proposed requirements is found in Water Column Sampling 
discussion in this preamble.
5. Surface vs. Subsurface Monitoring
    A commenter suggested that EPA distinguish between surface and 
subsurface monitoring in the first paragraph of the proposed rule. They 
also suggested that the OSC should authorize dispersant use and 
evaluate the need for monitoring actions. The commenter suggested the 
proposed updates seem to inappropriately replace the three-tiered SMART 
protocols which this commenter indicated should be implemented for 
surface dispersant use using USCG resources. They also

[[Page 40247]]

requested that the rule specify that the responsible party monitor 
subsurface dispersant injections. They also asked that the monitoring 
requirement updates not impede response actions or dispersant use and 
should be implemented only after there are available resources during a 
response. Regarding subsurface monitoring, the commenter also proposed 
that EPA use the documentation in the published Industry Recommended 
Subsea Dispersant Monitoring Plan--Version 1.0 as their basis for 
subsurface monitoring protocols. Similarly, a commenter requested a 
restructuring of the proposed rule to provide separate guidance for 
surface and subsurface dispersant use.
    The Agency believes the monitoring section is clear relative to the 
requirements for the subsurface and surface monitoring and that 
dividing the monitoring section into separate subsections would be 
duplicative and unnecessary. However, the final rule does identify 
specific requirements relative to surface versus subsurface 
applicability. This preamble provides additional context to the intent 
of the regulatory requirements for surface and subsurface monitoring.
    EPA notes that dispersant authorization of use is governed by a 
separate section of Subpart J (40 CFR 300.910) and is outside the scope 
of the new monitoring requirements for atypical dispersant use in this 
final action. The monitoring section of the final rule provides a 
minimum set of requirements the Agency believes are necessary for 
monitoring the use of dispersants in those situations covered by the 
applicability criteria.
    The Agency disagrees that the proposed updates inappropriately 
replace the three-tiered SMART protocols, which the commenter indicated 
should be implemented for surface dispersant use using USCG resources. 
According to the 2013 NRT Environmental Monitoring for Atypical 
Dispersant Operations, atypical uses of dispersant during a response 
were not addressed in the existing SMART monitoring program. The SMART 
protocols do not apply to subsurface dispersant application, and the 
monitoring requirements for surface application are intended to 
supplement, not replace, the SMART protocols.
    EPA disagrees that surface dispersant monitoring should be 
implemented using USCG resources to meet these regulatory requirements. 
The provisions of dispersant monitoring are appropriately the 
responsibility of the regulated community. USCG resources are intended 
to provide support in excess of commercially available resources. The 
SMART protocols do not limit surface dispersant monitoring to only USCG 
resources. The availability of government resources is not assured and 
does not satisfy the regulatory standard or intent of this rulemaking. 
Finally, while the OSC may choose to implement separate monitoring 
activities, the new monitoring requirements in this final rule are for 
the responsible party to implement and not directed towards any 
government agency or resources.
    EPA does not believe the monitoring requirement will in any way 
impede response actions or dispersant use and disagrees that monitoring 
requirements should be implemented only after there are available 
resources during a response. The Agency also notes steps taken for the 
deployment of subsurface dispersant injection equipment, including 
their associated time frames. The Agency does not believe deploying 
monitoring equipment should occur on a time frame that is longer than 
the deployment of subsurface dispersant injection equipment. As 
observed elsewhere in this preamble, the new monitoring provisions do 
not change current preparedness or planning regulatory requirements; 
the monitoring and data submissions that serve as the basis of this 
rule were established in the 2013 NRT Environmental Monitoring for 
Atypical Dispersant Operations document. The Agency believes that both 
industry and oil spill response organizations (OSROs) are aware of the 
NRT guidance document referenced immediately above and have since been 
preparing for monitoring requirements described in this rule. This 
final action provides notice to potential responsible parties of the 
expectation to identify and prepare for deployment of monitoring 
assets, to obtain data and information required during those discharge 
situations subject to this action, including response personnel, 
equipment, and sampling materials. This final action also allows 
potential responsible parties time to identify and have strategies in 
place to provide alternative resources for eventualities such as 
equipment failure, rather than wait until an incident occurs. The 
Agency encourages planning and preparedness efforts and supports these 
efforts with our interagency partners.

B. Information on Dispersant Application

    In the new monitoring regulations, the responsible party is 
required to document: (1) The characteristics of the source oil; (2) 
the best estimate of the oil discharge volume or flow rate, 
periodically reevaluated as conditions dictate, including a description 
of the method, associated uncertainties, and materials; (3) the 
dispersant used, rationale for dispersant choice(s) including the 
results of any efficacy and toxicity tests specific to area or site 
conditions, recommended dispersant-to-oil ratio (DOR); and (4) the 
application method(s) and procedures, including a description of the 
equipment to be used, hourly application rates, capacities, and total 
amount of dispersant. For subsurface discharges, the responsible party 
must also document the best estimate of the discharge flow rate of any 
associated volatile petroleum hydrocarbons, periodically reevaluated as 
conditions dictate, including a description of the method, associated 
uncertainties, and materials. Methods and materials are commonly used 
terminology in the technical and scientific community, explaining the 
procedures and equipment used to obtain the results. The description 
should allow the reader to understand how the data was obtained and to 
reconstruct the methodology to get similar results.
    As addressed in the preamble, the new monitoring requirements in 
this final action do not, for example, preclude the OSC from seeking a 
qualified third party to conduct additional monitoring or testing, from 
requiring the responsible party to use a third party to conduct the 
monitoring or testing where the OSC deems it appropriate, or from 
seeking supplemental information separately. Similarly, the final rule 
does not preclude the consideration of third-party testing or test 
results.
    A commenter expressed concern regarding the reliance on potentially 
responsible parties for spill characterization including estimates of 
blowout flow rates and spill volumes as the basis for dispersant 
application volumes. A commenter suggested that the responsible party 
should be required to disclose all information used in determining 
estimates of flow rates and spill volumes. Another commenter 
recommended that any estimates of spill volumes or blowout rates should 
be independently derived and not under the purview of the potential 
responsible party. This commenter also indicated concern that the rule 
seems to only contain reference to blowout-type releases and argued 
that all potential types and sources of spills should be included in 
the updates to the rule. The commenter also stated that other 
parameters (e.g., oil viscosity, emulsification, dispersant 
formulation, dose rate, mixing energy, water salinity,

[[Page 40248]]

and potential for dilution) should be included in the dispersant 
application decision-making process.
    The Agency understands the concerns regarding the reliance on 
responsible parties for spill characterization, including estimates of 
blowout flow rates and spill volumes as the basis for dispersant 
application volumes. EPA is specifying ``volume'' since the monitoring 
requirements also apply to certain near instantaneous discharges where 
``flow rate'' is not as applicable (e.g., catastrophic tank vessel 
casualty). However, the new monitoring requirements do not preclude the 
OSC from seeking non-responsible party evaluations, including 
independent government agencies or academia, for spill characterization 
including estimates of discharge flow rates and volumes.
    The new provisions require the responsible party to document the 
characteristics of the source oil and provide the best estimate of the 
oil discharge flow rate, periodically reevaluated as conditions 
dictate, including a description of the method, associated 
uncertainties, and materials. EPA agrees that the responsible party 
should disclose to the OSC all relevant information used in determining 
estimates of flow rates and spill volumes. This will provide the OSC 
with the necessary information for operational decision-making and 
coordination of the dispersant application monitoring.
    The Agency agrees that other parameters (e.g., oil viscosity) may 
inform the dispersant decision-making process, including dispersant 
application. For example, oil viscosity is an important parameter in 
characterizing the source oil and in conducting trajectory modeling as 
described in the Oil Distribution Analyses discussion in this preamble. 
The Agency believes these parameters are already inherently captured in 
the monitoring section, including the Dispersant Application and Oil 
Distribution Analyses discussions in this preamble, and therefore it is 
unnecessary to specifically list additional parameters.
    A commenter stated that the responsible party should not be 
required to provide documentation at the onset of a response if the 
documentation was previously provided in the preparedness or planning 
stages. The commenter suggested removing this section from the proposed 
rule. They stated that if a dispersant or other agent is on the 
Schedule, then by definition it is a viable response option. This 
commenter also stated that if the section is not removed, it should be 
amended to say hourly application rates are to be provided for 
subsurface dispersant applications only. They indicated that an hourly 
application rate would not apply to aerial or vessel types of 
application which are measured on the basis or spray assets, 
application speed, and spray system swath widths. This commenter also 
recommended that the section discussing the DOR be edited to indicate 
that the ratio may need to be changed from the initial recommended 
ratio in response to site-specific environmental conditions or the 
weathering condition of the oil.
    EPA disagrees that the responsible party should not be required to 
provide documentation at the onset of a response if the documentation 
was previously provided in the preparedness or planning stages and also 
disagrees with the suggestion that the section addressing such be 
removed from the proposed rule. The Agency also disagrees that listing 
of a dispersant or other agent on the Schedule defines it as a viable 
response option for any given response.
    Requiring the responsible party to provide documentation ensures 
that information is directly provided to the OSC and is relevant to the 
incident-specific discharge situation and also avoids any potential 
delays in information gathering. The Agency calls attention to existing 
regulatory requirements clearly establishing that being listed on the 
NCP Product Schedule is not itself a rationale or authorization to use 
that dispersant in any given situation, but rather that the product is 
available for consideration as a response option, as appropriate. 40 
CFR 300.920. The listing of a specific dispersant on the NCP Product 
Schedule does not mean that EPA approves, recommends, licenses, 
certifies, or authorizes the use of that dispersant on an oil 
discharge. The listing means only that data have been submitted to EPA 
as required by Subpart J of the National Contingency Plan, 40 CFR 
300.915.
    The Agency disagrees that the final rule should require hourly 
application rates be provided only for subsurface dispersant 
applications. Even if aerial or vessel types of application are 
measured based on spray assets, application speed, and spray system 
swath widths, the responsible party can calculate the volume of 
dispersant applied during the time in which it is applied. Certain 
American Society for Testing and Materials (ASTM) Standards (e.g., ASTM 
F1737/F1737M-19 Standard Guide for Use of Oil Spill Dispersant 
Application Equipment During Spill Response: Boom and Nozzle Systems; 
ASTM F1413/F1413M-18 Standard Guide for Oil Spill Dispersant 
Application Equipment: Boom and Nozzle Systems) may include procedures 
to assist in determining dispersant application rates. Furthermore, EPA 
clarified in the regulatory text that the daily reporting requirements 
for the actual amount of dispersant used is intended for each 
dispersant application platform.
    EPA does not believe that the DOR should be qualified as 
``initial'' to account for site-specific environmental conditions or 
the weathering condition of the oil. To the extent that the responsible 
party believes the DOR should be changed from the initial 
recommendation, they may request a change and should provide supporting 
documentation justifying the change for consideration by the OSC and 
RRT, as appropriate.
    A commenter also suggested that EPA should remove the requirement 
for measuring volatile petroleum hydrocarbons. They indicated these 
types of measurements are very difficult to obtain and fluctuate due to 
shifts in wind speed and direction or changes in sun exposure. They 
also argued that EPA should use already existing best practices for 
dispersant monitoring such as the American Petroleum Institute (API) 
guidelines on subsurface dispersant monitoring, API TR 1152. The 
commenter proposed specific language for this change.
    The Agency disagrees with the suggestion to remove the requirement 
for measuring volatile petroleum hydrocarbons. EPA recognizes the 
concern that these types of measurements may be difficult to obtain and 
may fluctuate due to shifts in wind speed and direction or changes in 
sun exposure for air sampling. However, these factors should not 
adversely affect measurements of these petroleum constituents in the 
water column as the result of a discharge where the subsurface 
application of dispersant may occur.
    The Agency disagrees with replacing ``. . . collection of all 
environmental data.'' with ``. . . collection of operational monitoring 
data.'' However for clarity, the Agency has replaced ``. . . collection 
of all environmental data.'' with ``. . . collection of environmental 
data within this section.'' The monitoring requirements focus on 
collecting environmental data to support dispersant use decision-making 
in response operations, and not on overall operational monitoring to 
evaluate how well other response options (e.g., in-situ burning) may

[[Page 40249]]

mitigate the negative effects of the oil discharge on sensitive 
environmental resources. The Agency recognizes an overall response 
strategy may incorporate operation monitoring to evaluate reducing the 
overall impact of an oil discharge and may include response options 
that are outside the scope of the dispersant monitoring section. 
However, the monitoring section in the final rule focuses on the 
environmental monitoring related to dispersant use. In addition, 
dispersants are not the only response option; there are other response 
options (e.g., mechanical recovery) available that may lower overall 
environmental damage. Decisions on use of dispersants and other agents 
during a response are to be made in accordance with the NCP and the 
governing statute(s). Environmental tradeoff methodologies where 
dispersants are considered must be in conformance with the statutory 
and regulatory authorities that govern dispersant use when considering 
the extent to which they can be used.
    As noted in the proposed rule, the goal of establishing a Schedule 
under the NCP is to protect the environment from possible damage 
related to spill mitigating products used in response to oil 
discharges. This goal is consistent with past preambles related to 
Subpart J. For example, the 1994 NCP final rule (59 FR 47407) noted, 
``. . . EPA believes that Congress' primary intent in regulating 
products under the NCP Product Schedule is to protect the environment 
from possible deleterious effects caused by the application or use of 
these products. In looking at the long- and short-term effects on the 
environment of all spill mitigating devices and substances, EPA has 
concluded that chemical and bioremediation countermeasures pose the 
greatest threat for causing deleterious effects on the environment.''
    A commenter indicated that they do not support the proposed 
provisions and expressed concerns regarding the role of the responsible 
party in dispersant operations and product selection. The commenter 
suggested that all dispersant-related activities and product selections 
be primarily advised by the NOAA SSC through the OSC and RRT with 
operational support from the responsible party. Similarly, a commenter 
requested that EPA clarify that the OSC, and not the responsible party, 
has final authority regarding the dispersant application practices. The 
commenter also suggested that new technologies such as open-cell 
elastomeric foams be used in conjunction with dispersants to mitigate 
environmental damage.
    EPA recognizes the concern regarding the role of the responsible 
party in dispersant operations and product selection. However, the NCP 
establishes the OSC's authority to direct response efforts, including 
overseeing dispersant use and monitoring in accordance with Subpart J 
of the NCP. See, e.g., 40 CFR 300.120. Also, SSCs may provide 
scientific support for operational decisions and coordinate on-scene 
scientific activity during a response, as described in the NCP under 40 
CFR 300.145(c). The use of other response mitigation technologies is 
outside the scope of this final action.

C. Water Column Sampling

1. Background and Baseline Sampling
    The final action requires the responsible party to collect a 
representative set of ambient background water column samples in areas 
not affected by the discharge of oil, at the closest safe distance from 
the discharge as determined by the OSC, and in the directions of likely 
oil transport considering surface and subsurface currents. The 
responsible party is also required to collect a representative set of 
baseline water column samples at such depths and locations affected by 
the discharge of oil absent dispersant application, considering surface 
and subsurface currents, oil properties, and discharge conditions. This 
collection of background and baseline water column samples is to follow 
standard operating and quality assurance procedures. These 
representative sets must be analyzed for the following variables: (1) 
In-situ oil droplet size distribution, including mass or volume mean 
diameter for droplet sizes ranging from 2.5 to 2,000 [mu]m, with the 
majority of data collected between the 2.5 and 100 [mu]m size; (2) in-
situ fluorometry and fluorescence signatures targeted to the type of 
oil discharged and referenced against the source oil; (3) dissolved 
oxygen (DO) (subsurface only); (4) total petroleum hydrocarbons, 
individual resolvable constituents including volatile organic compounds 
(VOC), aliphatic hydrocarbons, monocyclic, polycyclic, and other 
aromatic hydrocarbons including alkylated homologs, and hopane and 
sterane biomarker compounds; (5) methane, if present (subsurface only); 
(6) heavy metals, including nickel and vanadium; (7) turbidity; (8) 
water temperature; (9) pH; and (10) conductivity.
    A commenter expressed support for the proposed background sampling 
requirements. Another commenter expressed support for the proposed 
updates and suggested that the sampling also include background areas 
to better delineate the plume. That commenter stated that the sample 
collection and analysis should be paired with aerial and strobe imagery 
to more effectively assess the plume area. Another commenter also 
suggested the use of the ``Dispersed Oil Monitoring Plan'' developed by 
California Office of Spill Prevention and Response (OSPR), which 
provides an approach for water column sampling. Another commenter 
supported the proposed monitoring requirements but suggested they 
include establishing baseline conditions prior to product application. 
Another commenter suggested that EPA add an exception clause to the 
proposed rule which would require responsible parties to document why 
some or all sample collection requirements were not feasible during a 
given incident response.
    The Agency agrees with the commenter's suggestion to include 
background water sampling and has included such requirements in the 
final rule. The Agency believes this a rational and necessary addition 
since an understanding of background conditions is required for 
understanding the incremental effects of dispersants. Ambient 
background sampling characterizes relevant ambient water conditions 
unaffected by the discharged oil, serves to check instrument 
performance, and informs dispersed oil plume behavior and delineating 
plume boundaries. The Agency recognizes imagery technology may assist 
in more effectively assessing the plume area when paired with water 
sampling. The final rule requires that the responsible party consider 
available technologies to characterize dispersant effectiveness and oil 
distribution, which may include imagery technology. The Agency believes 
the specific approach suggested for water column sampling as outlined 
in the ``Dispersed Oil Monitoring Plan'' developed by OSPR is 
consistent with the approach established in these monitoring 
provisions.
    EPA agrees with commenters who requested the new monitoring 
requirements also include site-specific baseline monitoring of the oil 
discharge in the absence of dispersant application and is including 
such requirement in the final rule. The Agency believes that baseline 
monitoring will provide data absent dispersant application to evaluate 
physical dispersion relative to the effects of dispersant use. The 
baseline requirement is intended to consider the currents and oil 
characteristics, as well as other relevant discharge conditions such as 
the

[[Page 40250]]

discharge configuration or multiple discharge locations. The Agency 
also included similar clarifying language for the water column sampling 
in the dispersed oil plume provision. Conducting baseline monitoring 
absent dispersant application reduces potential uncertainties 
associated with dispersant effectiveness in the field and supports 
dispersant use decision-making in response operations. For subsurface 
dispersant application, this means initiating monitoring immediately 
prior to dispersant application to avoid disrupting dispersant 
application once it is initiated. The Agency does not believe that 
collection of baseline monitoring data immediately prior to subsurface 
dispersant application will delay response actions. Equipment for 
subsurface dispersant injection typically takes days to be deployed by 
vessels for offshore facilities and become operationally ready. Thus, 
there is an opportunity to also deploy monitoring equipment, prior to 
or concurrent with that of subsurface dispersant injection equipment, 
without delaying subsurface dispersant application. Of note, EPA is not 
requiring 24-hour analyses be conducted and results be provided before 
dispersant application may begin; only that samples be collected. The 
Agency notes again that the new monitoring provisions do not change 
current preparedness or planning regulatory requirements; the 
monitoring and data submissions that serve as the basis of this rule 
were established in the 2013 NRT Environmental Monitoring for Atypical 
Dispersant Operations document. Further, the Agency believes that 
industry and OSROs have been preparing for the requirements of this 
rule since the 2013 issuance of the NRT guidance document, and notes 
API issued its own guidelines in 2013 on subsurface dispersant 
monitoring (API TR 1152). This final action provides notice for a 
potential responsible party to identify and prepare for deployment of 
monitoring assets including identifying response personnel, equipment, 
and sampling materials. Potential responsible parties also have time to 
identify and plan for the need of alternative resources to account for 
events such as equipment failure, rather than wait until an incident 
occurs. The Agency, along with our interagency partners, continues to 
support and encourage these planning and preparedness efforts.
    The Agency recognizes that for certain atypical oil discharge 
situations where surface dispersants have been authorized, dispersant 
application may already be underway (e.g., surface dispersant use prior 
to the 96-hour after initial application threshold) or capable of being 
applied by aircraft prior to dispersant monitoring vessels being 
deployed (e.g., for surface dispersant application for oil discharges 
greater than 100,000 U.S. gallons within a 24-hour period). The final 
rule is not intended to impede surface dispersant application until 
vessels are deployed to begin baseline monitoring prior to the first 
dispersant application, nor to stop such operations once they have been 
authorized. However, EPA also understands that deployment of monitoring 
assets should begin before the 96-hour after initial application 
threshold is reached so as not to delay monitoring operations. 
Likewise, the initial application of authorized surface dispersant use 
by aircraft should not be delayed until surface monitoring assets are 
deployed. The Agency believes surface dispersant monitoring should be 
operational as soon as possible to allow for baseline monitoring 
because of its ability to inform the response efforts and is to be 
operational in accordance with the new monitoring requirements where 
the discharge meets the 96-hour after initial application threshold. To 
address concerns raised by commenters and avoid any misinterpretation 
that initial surface dispersant use by aircraft would be delayed, the 
Agency is clarifying the regulatory text, and specifically that for the 
monitoring requirements for any surface dispersant use in response to 
oil discharges of more than 100,000 U.S. gallons occurring within a 24-
hour period. The Agency is specifying that when any dispersant is used 
on the surface in response to oil discharges of greater than 100,000 
U.S. gallons occurring within a 24-hour period, the responsible party 
shall implement paragraphs (a) through (g) of this section as soon as 
possible for the entire or remaining duration of surface dispersant 
use, as applicable. Finally, the Agency recognizes the differences in 
subsurface versus surface dispersant application relative to discharge 
location. Dispersant application in the subsurface generally occurs 
close to the oil discharge location, while surface dispersant 
application to oil patches may at times occur further away from the oil 
discharge location. Multiple oil patches provide multiple opportunities 
to monitor surface dispersant application activities, including 
baseline monitoring. EPA is not suggesting that every oil patch in 
which dispersant is applied must be monitored, but that the responsible 
party implement a sampling strategy where representative oil patches 
are monitored for baseline data and for the duration of dispersant 
operations.
    EPA disagrees with the commenter who suggested the addition of an 
exception clause, which would require responsible parties to document 
why some or all sample collection requirements were not feasible during 
a given incident response. The commenter did not identify why some or 
all sample collection requirements would not be feasible. The Agency 
believes that such an exception would be overly broad. The responsible 
party is required to follow established standard operating and quality 
assurance procedures when collecting water column samples. Some 
commenters expressed general agreement with the need for monitoring but 
said that the proposed requirements add unnecessary analytical 
parameters and that such requirements may actually delay response 
actions. A commenter also stated that monitoring should be incident 
specific and be under the responsibility of the OSC and responsible 
party.
    The Agency disagrees that the proposed requirements add unnecessary 
analytical parameters and that such requirements may actually delay 
response actions. Each oil discharge represents a unique situation with 
distinct conditions which may require various response methods. When 
dispersants are applied to an oil discharge, field monitoring can be 
used to inform operational decisions by gathering site-specific 
information on the overall effectiveness, including the transport and 
environmental effects of the dispersant and the dispersed oil. The 
Agency disagrees that the monitoring requirements for dispersant use 
are limited in scope to evaluating the initial effectiveness of the 
dispersant application. The Agency is requiring that sample collection 
follow established standard operating and quality assurance procedures 
that are reliable and defensible. Elements of monitoring plans are 
generally described in various guidance documents on standard operating 
and quality assurance procedures for environmental sampling.
    The Agency disagrees with the premise that monitoring requirements 
could hamper response activities from occurring in a timely manner. 
Specifically, the monitoring requirements are not designed to delay or 
impede response actions related to the deployment of mechanical 
recovery, in-situ burning, or dispersant-related equipment. The Agency 
also notes the time frame for deployment of subsurface dispersant 
injection equipment by

[[Page 40251]]

vessels for offshore facilities is not expected to be different than 
the deployment of subsurface dispersant injection equipment. The final 
rule provides notification for a responsible party to identify and 
prepare for potential deployment of monitoring assets prior to an 
incident. These assets may include response personnel, equipment, and 
sampling materials, as well as alternative resources and procedures to 
account for events such as equipment failure. Comments regarding the 
OSC's roles and responsibilities are addressed in Roles and 
Responsibilities for Monitoring Operations discussion in this preamble.
    A commenter stated that elements of 3-D and 4-D modelling should be 
included to broaden the overall understanding of subsurface conditions. 
The Agency acknowledges the modeling suggestion and addresses 
trajectory modeling in the Oil Distribution Analyses discussion in this 
preamble. The same commenter recommended updates to the proposed rule 
language droplet size distribution analysis; however, the Agency 
believes that the commenter intended for the droplet size to be in 
micrometers ([micro]m) instead of picometers (pm) in its recommended 
rule language because for the purpose of measuring dispersed oil, 
droplet size is typically reported in micrometer units.
    Some commenters indicated that water sampling requirements are more 
appropriate for the NRDA process. The Agency disagrees that the water 
sampling requirements in this final action are more appropriate for the 
NRDA process and believes that comprehensive monitoring for discharge 
situations subject to this action is necessary to determine the overall 
effectiveness of dispersants and should extend beyond the initial 
dispersant application to include the transport and environmental 
effects of the dispersant and dispersed oil in the water column. 
Furthermore, the Agency notes that the SMART Tier III protocol also 
includes water sampling.
    Another commenter supported the proposed monitoring requirement and 
suggested that EPA require sampling and analysis of VOCs, semi-volatile 
compounds, and the full suite of metals and metalloids. This commenter 
also recommended the use of specific sampling devices. This final 
action requires water column samples in the dispersed oil plume to be 
analyzed for total petroleum hydrocarbons, which includes VOCs and 
semi-volatile compounds. Additionally, the commenter is not clear about 
which metals and metalloids to analyze for and which analytical methods 
to use. The Agency is requiring water samples be analyzed for heavy 
metals, including nickel and vanadium, which are typically found in 
crude petroleum oil. EPA does not specify sample collection methods or 
devices in the water column sampling requirements. The Agency is 
requiring that sample collection follow established standard operating 
and quality assurance procedures that are reliable and defensible; 
standard operating procedures should describe the appropriateness of 
the sampling method, including the equipment needed for sample 
collection.
    A commenter indicated support specifically for daily water column 
sampling in the dispersed plume. This commenter also suggested that EPA 
develop protocols for surface and subsurface current tracking. EPA 
acknowledges a commenter's support specifically for daily water column 
sampling in the dispersed plume. EPA does not believe it is appropriate 
to develop protocols for surface and subsurface current tracking 
because the Agency believes these issues are best addressed in a 
DMQAPP. The final rule requires that the responsible party consider 
available technologies to characterize dispersant effectiveness and oil 
distribution.
    A commenter expressed support for the proposed monitoring 
requirements but suggested that EPA provide minimum required monitoring 
guidance. Such guidance might include timing, sample frequency, number 
of samples, spatial locations, and sampling depths. This commenter also 
had questions regarding thresholds for each of the proposed monitoring 
parameters that would require a cessation of adjustment in response 
actions. For example, they questioned whether there is a threshold 
lower value for pH or DO in the water column, at which point responders 
would shift response actions until the parameter values were within the 
acceptable range. The commenter suggested that these thresholds should 
be established for each sampled parameter. Due to the potential for 
dispersants to enhance bioavailability to aquatic organisms, the 
commenter also requested that bioaccumulation of Total Petroleum 
Hydrocarbons (TPH) and heavy metals in benthic biota be added to the 
monitoring requirements along with characterization of these components 
in the sediment. They also indicated that Ultraviolet (UV) radiation 
monitoring could enhance plume characterization as these data are 
inexpensive to collect and are useful for understanding the oil 
weathering state.
    The Agency acknowledges the commenter's suggestions regarding 
monitoring guidance for timing, sample frequency, number of samples, 
spatial locations, and sampling depths. The Agency believes that the 
final rule provides flexibility to develop monitoring strategies that 
can be tailored to an incident-specific dispersant use situation. 
Because these situations may vary, the Agency did not establish 
specific parameters for sample frequency, number of samples, spatial 
locations, and sampling depths other than what has been provided in the 
final rule. However, the monitoring approach should include periodic 
sampling of previously sampled locations including near the discharge 
source to evaluate changes in parameters over time at those locations.
    Additionally, EPA did not propose to establish monitoring 
thresholds in the monitoring section and the establishment of 
thresholds is out of scope for these final monitoring provisions. EPA 
recognizes the commenter's concern regarding monitoring in benthic 
biota, sediment characterization, and UV radiation monitoring. The 
final action does not prevent the OSC or appropriate RRT agencies from 
requiring additional monitoring parameters, which may include benthic 
biota monitoring, sediment characterization, or UV radiation 
monitoring. The final rule requires that the responsible party consider 
available technologies to characterize the dispersant effectiveness and 
oil distribution to determine changes in the condition of the oil due 
to weathering.
    A commenter suggested that incorporating API TR1152 (Industry 
Recommended Subsea Dispersant Monitoring Plan, Version 1.0, API 
Technical Report 1152, September 2013) by reference would meet the 
requirements of the subsection. The Agency disagrees that the 
monitoring requirements need to incorporate by reference API TR1152 or 
that adherence to it meets the requirements of the subsection. For 
example, API TR1152 presents a phased approach which allows subsurface 
dispersant injection to commence after implementing limited visual 
confirmation and air monitoring. The Agency disagrees that such an 
approach is appropriate for the atypical situations expected to trigger 
applicability of these requirements, particularly for subsurface 
dispersant application. While SMART protocols include visual 
observation for surface dispersant use, air monitoring is used for in-
situ burning situations. In addition, the SMART protocols are not 
applicable to subsurface dispersant application. The expectation is 
that for

[[Page 40252]]

those atypical dispersant use situations, the expanded monitoring 
provisions put forth in this action are necessary to effectively inform 
dispersant use. As previously discussed in this preamble, the 
requirements set forth in this action are informed by lessons learned 
during the Deepwater Horizon oil spill and are consistent with the 2013 
NRT Environmental Monitoring for Atypical Dispersant Operations 
guidance document.
2. Dispersed Oil Plume Daily Sampling
    The new provisions require the responsible party to collect daily 
water column samples in the dispersed oil plume, following standard 
operating and quality assurance procedures, at such depths and 
locations where dispersed oil is likely to be present. This daily 
sampling must include the following variables: (1) In-situ oil droplet 
size distribution, including mass or volume mean diameter for droplet 
sizes ranging from 2.5 to 2,000 [mu]m, with the majority of data 
collected between the 2.5 and 100 [mu]m size; (2) in-situ fluorometry 
and fluorescence signatures targeted to the type of oil discharged and 
referenced against the source oil; (3) dissolved oxygen (DO) 
(subsurface only); (4) total petroleum hydrocarbons, individual 
resolvable constituents including volatile organic compounds, aliphatic 
hydrocarbons, monocyclic, polycyclic, and other aromatic hydrocarbons 
including alkylated homologs, and hopane and sterane biomarker 
compounds; (5) methane, if present (subsurface only); (6) heavy metals, 
including nickel and vanadium; (7) turbidity; (8) water temperature; 
(9) pH; and (10) conductivity. Several commenters indicated support for 
the water column sampling section of this final rule and agreed that 
these provisions will add value during a response.
3. Water Column Samples Analyses
    The responsible party must collect ambient background, baseline, 
and dispersed oil plume water column samples following standard 
operating and quality assurance procedures. The water column samples 
are to be analyzed, as applicable, for: Droplet size distribution; 
fluorometry and fluorescence; dissolved oxygen; total petroleum 
hydrocarbons; methane; heavy metals; turbidity; water temperature; pH; 
and conductivity. The Agency is not including the proposed requirement 
to analyze for carbon dioxide in this final action. The specific 
provisions are as follows:
i. In-Situ Oil Droplet Size Distribution Analysis, Including the Mass 
or Volume Mean Diameters Between Droplet Sizes Ranging From 2.5 to 2000 
[mu]m, With the Majority of Data Collected Between the 2.5 and 100 
[mu]m Sizes
    A commenter requested additional descriptions of the methodology 
for determining droplet size. They expressed concern that while 
techniques such as Laser In-situ Scattering and Transmissometry (LISST) 
can measure droplet size, there needs to be a process for confirming 
that the particles are dispersed oil versus other types of suspended 
particles. They suggested the concurrent use of fluorometers to help 
differentiate oil droplets from other particles. Another commenter 
similarly suggested that EPA clarify that droplet measurement methods 
should include fluorometers or similar instrumentation. This commenter 
also stated that the use of fluorometry could aid in confirming the 
measurement of actual oil droplets as opposed to other particles in the 
water column.
    A commenter discussed concerns related to the feasibility of in-
situ droplet size measurements. They indicated that LISST has a droplet 
size detection limit of around 500 [micro]m, well below the upper limit 
of the proposed range of 2.5-2000 [micro]m. They also stated that there 
is currently no commercially available droplet measurement 
instrumentation that is operational in deep water to size ranges up to 
2000 [micro]m. They indicated that if this instrumentation did become 
available in the future, it would likely require remotely operated 
vehicles (ROV) or additional vessel support, which would be impossible 
to deploy without interfering with response activities. This commenter 
recommended that EPA allow for alternative methods for measuring 
droplet size including high definition, high speed photography, or 
sonar as these technologies mature.
    A commenter indicated strong support for the proposed updates to 
this section of the proposed rule, stating that droplet size 
measurement is critical for response actions. Similarly, a commenter 
stated that they agreed with EPA that the collection of droplet size 
distributions will add valuable information during response actions.
    The Agency is not requiring the use of specific oil size droplet 
measurement methods or instrumentation. Further, the Agency is not 
requiring the use of single instrument, methodology, vessel, or ROV be 
used to collect the required information. How to collect the 
information is left for the responsible party to determine and document 
in the DMQAPP. The Agency is requiring that droplet size information be 
collected because oil droplet sizes generally decrease with dispersant 
addition and because oil droplets below 100 [micro]m generally remain 
entrained into the water column, relative to larger particles that may 
eventually resurface over time. Furthermore, collecting oil droplet 
sizes of a broader range informs trajectory modeling used to predict 
the fate and transport of dispersed oil and to inform sampling 
locations. This final rule requires that sample collection follow 
established standard operating and quality assurance procedures that 
are reliable and defensible; standard operating procedures should 
include the equipment needed for sample collection. The Agency agrees 
with the concurrent use of fluorometers to help differentiate oil 
droplets from other particles. The final rule includes fluorometry as 
part of the water sampling requirements. The Agency does not designate 
specific methods or devices in this final rule, including methods for 
measuring droplet size such as high definition, high speed photography, 
or sonar.
ii. In-Situ Fluorometry and Fluorescence Signatures Targeted to the 
Type of Oil Discharged and Referenced Against the Source Oil
    A commenter indicated that the proposed fluorometry measurements 
are redundant and less informative than the droplet size measurements. 
They suggested that collection of these measurements be optional and 
handled on a case-by-case basis. This commenter also requested that EPA 
substantiate the need to replace the existing SMART protocols, which 
provide similar monitoring approaches including the use of simple 
fluorometry in the SMART Tier II protocol.
    Another commenter suggested additional resources for planning and 
conducting sample collection and monitoring in the field. They 
indicated that the use of SMART Tier III fluorometry tows could 
facilitate the collection of before and after treatment samples from 
outside and inside the slick area.
    Other commenters expressed support for the proposed fluorometry 
measurements, but requested clarification related to the use of in-situ 
fluorometry in the response context. These commenters suggested that 
EPA clarify that oil weathering and dispersion can impact the 
fluorescence of oil components. These commenters also indicated that 
site-specific calibration may be necessary in

[[Page 40253]]

response to changing turbidity or particle size distribution. A 
commenter suggested that EPA should make it clear that without 
measurement of fluorescence signatures (fluorescence measures across 
multiple wavelengths), most commonly used in-situ fluorometers only 
provide an approximate indication of oil in the water column. These 
commenters requested that EPA clarify that these methods cannot 
distinguish oil signals, and added that most dispersants fluoresce as 
well, potentially adding to difficulties interpreting in-situ 
fluorescence measurements.
    The Agency agrees that collection of samples from outside and 
inside the slick area prior to and after dispersant application serves 
to inform the initial effectiveness of surface dispersant application. 
SMART Tier II and III protocols similarly note three primary target 
locations: (1) Ambient background water (no oil); (2) oiled surface 
slicks prior to dispersant application, and (3) post-application, after 
the oil has been treated with dispersants. EPA emphasizes that these 
water column sampling requirements are not replacing the SMART 
protocols and that EPA assumes the SMART Tier III protocol is also 
being implemented as part of the response. EPA is requiring that sample 
collection under the new monitoring requirements follow established 
standard operating and quality assurance procedures.
    The Agency disagrees that fluorometry is a redundant measurement. 
For crude petroleum oils, the aromatic fraction is responsible for the 
fluorescence property of petroleum. Instruments that measure particle 
size, such as the LISST, do not distinguish between oil droplets and 
other types of particles in the same size range. Fluorometers can be 
targeted to the type of oil discharged and the excitation and emission 
wavelengths chosen should match the aromatic properties of the oil 
discharged. Fluorescence is a valuable screening tool deployed during a 
response, providing a rapid indication of potential dispersed oil in 
the water column, as well as an indicator of dispersion effectiveness. 
The final rule requires the responsible party to conduct a fluorescence 
intensity analyses on water samples collected to determine fluorescence 
signatures of the dispersed oil. To the extent the commenter believes 
that most dispersants fluoresce, potentially adding to the difficulty 
interpreting in-situ fluorescence measurements, the Agency expects this 
concern will be addressed in the DMQAPP.
iii. Dissolved Oxygen (DO) (Subsurface Only)
    A commenter indicated support for the collection of DO samples and 
agreed with the proposed approach of using the Winkler titration method 
to verify sample results. A commenter requested that the proposed rule 
be updated to require DO measurements using the best available devices. 
They also indicated that measurement verification using Winkler 
titration is impractical and outdated. They recommended instead that 
verification be conducted by the use of consistent sensor cleaning 
procedures, calibration tests, and redundant sensors which can be 
compared. In an effort to avoid slowing the process and information 
flow, they recommended that verification should only be required on a 
fraction of collected samples instead of for every sample.
    The Agency recognizes that relying solely on measurements from in-
situ oxygen instruments may lead to an erroneous interpretation of 
oxygen data. While the Agency does not require Winkler titration as 
confirmatory analysis in the final rule, the Agency believes that ex-
situ DO measurements should generally be conducted using Winkler 
titrations to confirm in-situ DO measurements and notes that the OSC 
can require DO measurements be conducted using Winkler titrations if 
necessary. The Agency disagrees that measuring DO using Winkler 
titrations is impractical and outdated. For example, the use of Winkler 
titrations to measure dissolved oxygen provides for accurate 
measurements in subsurface waters where DO may already be low. 
Additionally, the final rule does not state the number of samples 
required for DO verification because this and the confirmatory analysis 
methodology should be addressed in the DMQAPP to ensure that DO 
measurements follow established standard operating and quality 
assurance procedures that are reliable and defensible.
    The Agency agrees with commenters' concerns regarding tailoring DO 
measurements. DO is an important variable to monitor in the application 
of dispersants, particularity in subsurface waters that may inform 
operational decisions. For surface dispersant application, DO is 
expected to be higher in the mixed layer in the surface water. Because 
DO is expected to be higher in the mixed layer of the surface water, 
the Agency is not finalizing the proposed DO requirements for surface 
dispersant application. However, the Agency strongly recommends RRTs 
and OSCs, as part of their authorized activities under the NCP, 
consider adding DO as a monitoring requirement for surface dispersant 
application in surface waters where DO is believed to be limited.
iv. Total Petroleum Hydrocarbons, Individual Resolvable Constituents, 
Including Volatile Organic Compounds, Aliphatic Hydrocarbons, 
Monocyclic, Polycyclic, and Other Aromatic Hydrocarbons, Including 
Alkylated Homologs, and Hopane and Sterane Biomarker Compounds
    A commenter expressed support for the proposed requirements to 
analyze TPHs, individual resolvable constituents, including volatile 
petroleum hydrocarbons and branched/normal aliphatic hydrocarbons. A 
commenter also indicated support for the requirements to analyze 
monocyclic, polycyclic, and other aromatic hydrocarbons, including 
their alkylated homologs and hopane/sterane biomarker compounds. They 
suggested that results from these analyses can inform forensic 
assessment of collected samples. A commenter suggested that EPA should 
specify a standard analytical method for performing these analyses 
(from the multiple methods available) for water column samples. A 
commenter indicated that, as discussed by EPA, measurement of TPH alone 
is inadequate when attempting to assess the fate and effects of 
dispersed oil during a response. A commenter also communicated support 
for the proposed rule, adding that identifying concentrations of oil 
and associated components, as opposed to only the presence or absence 
of oil, is critical.
    A commenter suggested that EPA adopt quick-screening methods for 
sampling TPHs by means of a hand-held gas chromatograph flame 
ionization detector (GC-FID). They indicated that detailed analysis for 
these components will not inform response decision-making and should 
instead be completed as part of the NRDA process. This commenter also 
suggested that the analytical requirements should apply to a fraction 
of the collected samples as opposed to every water sample.
    EPA did not propose to use only TPH measurements to assess the fate 
and effects of dispersed oil, but rather included it along with other 
monitoring approaches in the final rule to assess the fate and effects 
of dispersed oil. The Agency is not specifying the type of analytical 
equipment or methods needed for sample collection. The Agency believes 
that standard operating procedures should describe the appropriateness 
of the sampling method and should be included in the DMQAPP.

[[Page 40254]]

    The Agency disagrees that the detailed analysis of oil constituents 
is more appropriate for the NRDA process, and believes that 
comprehensive monitoring in certain discharge situations is necessary 
to determine the overall effectiveness of dispersants and should extend 
beyond the initial dispersant application to include the transport and 
environmental effects of the dispersant and dispersed oil in the water 
column. The final rule requires that sample collection follow 
established standard operating and quality assurance procedures that 
are reliable and defensible. Additionally, the final rule does not 
state the number of water samples required for analysis because this is 
to be determined on a case-by-case basis.
v. Methane, if Present (Subsurface Only)
    A commenter responded to this section of the proposed rule which 
requires the measurement of methane in water column samples during 
response activities. This commenter stated that monitoring of methane 
is unnecessary because it is linked to potential oxygen depletion, and 
therefore, is sufficiently covered with the monitoring requirements for 
DO.
    The Agency agrees that methane biodegradation may lead to oxygen 
depletion but disagrees that it is sufficiently covered by the 
monitoring requirements for DO. Depletion of DO may be caused by other 
factors such as the biodegradation of lower molecular weight alkanes. 
Should DO depletion occur, understanding the correlation of potential 
substrates to DO is an important factor relative to the effects of 
dispersant use and may inform response decision-making.
vi. Heavy Metals Analysis, Including Nickel and Vanadium
    Some commenters expressed support for the proposed updates. They 
agreed that heavy metals should be analyzed in monitoring samples, 
including nickel and vanadium concentrations. A commenter expressed 
concern that the analysis of heavy metals in water column samples does 
not have any relevance to monitoring of dispersed oil and does little 
to inform response decision-making. The commenter indicated they see no 
operational reasoning behind the collection of these data and suggested 
that the requirement for heavy metal analyses would lead to unnecessary 
delays and costs during response efforts.
    The Agency disagrees that the analyses of heavy metals in water 
column has no relevance to monitoring of dispersed oil and does little 
to inform response decision-making. Crude petroleum oil may contain 
heavy metals, including nickel and vanadium.\2\ The December 17, 2010 
OSAT report entitled ``Summary Report for Sub-Sea and Sub-Surface Oil 
and Dispersant Detection: Sampling and Monitoring'' specifically 
included nickel and vanadium as part of the water sampling analyses. 
Furthermore, EPA specifies that dispersant products must be analyzed 
for arsenic, cadmium, chromium, copper, lead, mercury, nickel, zinc, 
plus any other metals that may be reasonably expected to be in the 
product sample as part of the NCP product listing requirements under 40 
CFR 300.915(a)(11)(i). Dispersing oil may increase the bioavailability 
of those heavy metals to marine organisms. In addition, monitoring 
heavy metals serves to inform water quality standards and thus is an 
important parameter to include in the monitoring requirements. The 
Agency does not expect these monitoring requirements to lead to delays 
given the flexibility provided under the new daily reporting 
provisions. Furthermore, the Agency disagrees with the characterization 
that these analyses lead to unnecessary costs for the reasons stated 
above in this paragraph and elsewhere in this Response to Comments 
document that address the appropriateness of this final action.
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    \2\ Walters, C. (2021). Petroleum. In Kirk-Othmer Encyclopedia 
of Chemical Technology, (Ed.). https://doi.org/10.1002/0471238961.1518090702011811.a01.pub3.
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vii. Turbidity
    Commenters indicated support for the proposed turbidity measurement 
requirement. A commenter stated that turbidity measurements are useful 
for determining the potential for dispersants and other products to act 
as sinking agents. The commenter suggested that in cases where 
turbidity may cause treated oil to sink, the use of dispersants or 
other treating agents should be prohibited.
    A commenter who also indicated support for the proposed 
requirements for the collection of turbidity data agreed with EPA 
regarding concerns about the potential for agents to enhance the 
formation of oil-mineral aggregates (OMA) and marine oil snow (MOS) in 
the water column, putting benthic ecosystems at risk.
    The Agency acknowledges commenters' support for the turbidity 
requirement. Turbidity is a general measure of water clarity and is 
measured by how much the amount of material suspended in water 
decreases the passage of light through the water. Suspended materials 
may include soil particles (clay, silt, and sand), algae, plankton, 
microbes, and other substances. Turbidity measurements provide a 
relatively quick assessment of suspended materials in the water bodies 
and are useful in determining the presence of materials that could 
interfere with oil particle size measurements. Finally, turbidity is 
included as a monitoring parameter in the SMART Tier III protocol.
    The Agency notes that prohibition of the use of chemical agents is 
not addressed in this final action. Furthermore, dispersants are not 
sinking agents because they are not intended to sink the oil to the 
bottom of a water body and are defined separately from sinking agents 
in the NCP. However, the Agency recognizes concerns regarding the 
potential for dispersed oil as one pathway to contribute to Marine Oil 
Snow Sedimentation and Flocculent Accumulation (MOSSFA) in the water 
column that could potentially lead to settling. This final action does 
not prevent the OSC or RRTs, as part of their authorized activities 
under the NCP, from requiring additional monitoring parameters, which 
may include benthic biota monitoring, sediment characterization, and 
other physical measurements of solids in the water (e.g., total 
suspended solids).
viii. Water Temperature, pH, and Conductivity
    The Agency received no comments specific to these provisions and is 
finalizing the requirements as proposed.
ix. Carbon Dioxide (CO2)--Removed
    A commenter responded to the section of the proposed rule which 
requires the measurement of CO2 in water column samples 
during response activities. This commenter indicated that the proposed 
rule is unclear in term of the benefits that CO2 monitoring 
provides that are not already provided by DO monitoring. They also 
expressed concern that there is a limit to the number of sensors that 
can be deployed from a vessel during a response. The commenter stated 
that adding CO2 to the analysis suite complicates the 
deployment of these instrument arrays.
    The Agency notes that the aerobic biodegradation of oil 
constituents not only consumes DO but would also produce 
CO2. Increases in the CO2 concentration that 
coincide with decreases in the DO concentration would provide credible 
evidence that biodegradation of oil is occurring. The Agency proposed 
measuring the in-situ CO2 for subsurface dispersant

[[Page 40255]]

applications because the Agency believed it would be a good indicator 
of microbial oxidation and inform the OSC on potential fate. However, 
the Agency agrees that adding CO2 sensors may not always be 
practicable and that the other monitoring requirements indirectly 
inform potential biodegradation. Therefore, the Agency is not 
finalizing this proposed requirement at this time. The RRTs and OSCs, 
as part of their authorized activities under the NCP, may still 
consider adding CO2 measurements and other biodegradation 
characterization assessments on a case-by-case basis.

D. Oil Distribution Analyses

    The new provisions include requirements for the responsible party 
to characterize the dispersant effectiveness and oil distribution, 
including trajectory analysis. As the OSC's oversight role over the 
responsible party is already established in the NCP, the Agency has 
removed the phrase ``in consultation with the OSC'' for Sec.  
300.913(c) the oil distribution analysis. This characterization is to 
consider available technologies, account for the condition of oil, 
dispersant, and dispersed oil components from the discharge location, 
and describe any associated uncertainties.
    Several commenters supported EPA's proposed language for Sec.  
300.913(c). A commenter supported this section but commented that the 
regulation should recognize the limitations of oil distribution 
analyses in areas that lack good ocean current predictive models or 
observational data. Another commenter expressed strong support for 
efforts to elucidate dispersant effectiveness but noted that 
effectiveness monitoring should be used only when it does not impede 
response operations. Another commenter stated that EPA should 
acknowledge that the available methods for anticipating the movement of 
dispersed oil plumes are limited and may complicate the monitoring 
process. A commenter noted that sampling and monitoring programs should 
acknowledge uncertainties about where an oil plumes may travel.
    The Agency recognizes oil distribution analyses may be affected by 
the data quality used to inform the analysis, which also includes 
parameters based on assumptions. In addition, trajectory models, which 
are used to predict the movement of dispersed oil plumes, may have 
uncertainties associated with modeling parameters. EPA is amending the 
regulatory text to clarify that oil distribution analyses includes 
trajectory modeling since this is an essential aspect of dispersed oil 
movement as the result of dispersant application, particularly in areas 
where water currents are highly influential to the oil discharge and 
inform water sampling locations. EPA agrees with concerns that these 
uncertainties could affect sampling and monitoring programs. Therefore, 
the Agency is amending the regulatory text to recognize uncertainties 
associated with trajectory modeling as part of the distribution 
analysis.
    A commenter suggested including a NOAA SSC in the review of data 
provided in this section to provide valuable credibility and support to 
the OSC, while noting that perceptions of the responsible party 
directing the process should be avoided. Another commenter suggested 
EPA might want to consider including directions for the use of local 
expertise in these analyses.
    The NCP describes the role of SSCs under 40 CFR 300.145(c) to 
include providing scientific support for operational decisions and for 
coordinating on-scene scientific activity during a response, as 
requested by the OSC. Coordinating on-scene scientific activity during 
a response may include consideration of input from local experts. The 
NCP also describes the OSC's roles and responsibilities under 40 CFR 
300.120, which includes directing response efforts and coordinating all 
other efforts at the scene of a discharge. As a result, EPA believes 
the NCP already sufficiently recognizes the SSC's role in support of 
the OSC.
    Some commenters stated that the rule needs to be clearer on what is 
required for surface monitoring and what is required for subsea 
monitoring, suggesting that each subsection should be divided into the 
aspects. These commenters also suggested that EPA should consider 
changing ``best available technologies'' to ``best practicable 
technologies'' in this section, to avoid equipment that is not suitable 
for field conditions. A commenter stated that the best available 
technology requirement should acknowledge aerial photography as a tool 
to measure effectiveness, as this was a key method of assessment during 
the Deepwater Horizon response. The commenter also stated that the 
relative effectiveness of surface application should be determined 
using the SMART protocols, noting that the amount of oil on the surface 
to which dispersants are being sprayed is impossible to determine, so 
effectiveness can't be quantified, and that the analytical equipment 
often cannot return to the spray site in time to capture the 
information requested as the dispersant plume quickly dilutes or cannot 
be found.
    The Agency believes the final rule is clear relative to the 
requirements for subsurface and surface monitoring and that dividing 
the monitoring section into separate subsections is unnecessary. The 
Agency has noted in the regulatory text and provided additional 
clarification in this preamble to delineate where requirements are 
different. EPA recognizes the commenter's concern relative to the term 
``best available technology'' but disagrees that it should be changed 
to ``best practicable technologies'' to avoid equipment that is not 
suitable for field conditions. The proposal did not specify equipment 
in the Oil Distribution Analyses section, but rather included the term 
``best available technology'' to capture advances in technology (e.g., 
modeling and equipment). The intent was to ensure these advances in 
characterizing the dispersant effectiveness and oil distribution 
continue to be implemented. For example, oil distribution is typically 
informed by trajectory modeling to predict the movement of dispersed 
oil plumes. The Agency recognizes that improvements to trajectory 
modeling continue over time and seeks to incorporate such advancements 
in the new monitoring requirements. The Agency is finalizing the term 
``considering available technologies'' instead of the term ``best 
available technology.'' Available technologies used and their 
applicability to the specific discharge situation should be described 
in the DMQAPP. The Agency believes this new provision provides the 
opportunity for the OSC to consider relevant technologies and addresses 
the intent to capture advances in technology.
    EPA disagrees that aerial photography, as a tool to measure 
effectiveness, should be acknowledged as a best available technology. 
EPA recognizes that the SMART Tier I protocol bases initial dispersant 
effectiveness assessment using photographic job aids or advanced remote 
sensing instruments flying over the oil slick with a trained observer. 
EPA also recognizes that NOAA developed a Dispersant Application 
Observer Job Aid, which is a field guide for responders trained in 
observing and identifying dispersed and undispersed oil, describing oil 
characteristics, and reporting this information to decision-makers. 
However, EPA is unaware of any similar NRT-approved protocols or NOAA-
developed job aids to assess the initial effectiveness of subsurface

[[Page 40256]]

dispersant application. Furthermore, the requirements for monitoring 
surface dispersant application for atypical dispersant applications 
necessitate specific considerations beyond those addressed by SMART. 
According to the 2013 NRT Environmental Monitoring for Atypical 
Dispersant Operations guidance document, such atypical uses of 
dispersant during a response were not addressed in the existing SMART 
monitoring program. While some monitoring requirements are only 
included in the SMART Tier III protocol (e.g., turbidity, pH, 
conductivity, temperature), other requirements (e.g., in-situ droplet 
size distribution) important to understanding dispersant effectiveness 
are not.
    A commenter stated that the relative effectiveness of the surface 
application should be determined by using the SMART protocols, but also 
noted the analysis equipment often cannot return to the spray site in 
time to capture the information requested, because the dispersant plume 
quickly dilutes or cannot be found. According to the SMART protocols, 
Tier II and III use towed fluorometry to characterize effectiveness, 
requiring the vessel to pass through the oil slick after dispersant is 
applied. For the SMART Tier II protocol, the team collects data in 
three primary target locations: (1) Ambient background water (no oil); 
(2) oiled surface slicks prior to dispersant application, and (3) post-
application, after the oil has been treated with dispersants. The Tier 
III protocol follows procedures from the Tier II protocol, and in 
addition collects information on the transport and dispersion of the 
oil in the water column to help verify that the dispersed oil is 
diluting toward background levels. The commenter's characterization 
that the dispersant plume quickly dilutes or cannot be found seems 
contrary to their recommendation to use the SMART protocols data 
collection procedures. The Agency notes that the commenter did not 
provide supporting evidence that the dispersed oil plume always quickly 
dilutes and cannot be found. The assumption that dispersed oil plume 
quickly dilutes and cannot be found does not account for the many 
factors that impact dispersant effectiveness, including for example the 
specifics of the discharge situations (e.g., continuous discharges), 
the weathering of the oil, and the mixing conditions. Both the SMART 
protocols and the monitoring provisions finalized in this action are 
designed to provide feedback on the efficacy of dispersant application 
in dispersing the oil. The Agency believes monitoring provides 
information on dispersant effectiveness, including for those 
occurrences of non-detection of dispersed oil after dispersant 
application. The Agency also notes that advances in technology using 
remote sensing vehicles may allow for data collection prior to and 
after dispersant application with responders in an offset area to 
inform the fate and transport of the oil plume.
    A commenter stated the monitoring requirements need the concurrence 
of the DOI's regional response team (RRT) representative as well, since 
these results provide information relevant to DOI's trust resources. In 
addition, a commenter stated that because of inherent conflict of 
interest, a qualified third party acceptable to the OSC, EPA, and the 
DOI RRT representatives should conduct all monitoring.
    EPA recognizes conflicts of interest concerns. The Agency notes 
that the NCP addresses the OSC's oversight role of the responsible 
party as part of the OSC's authority. The final rule does not preclude 
the OSC from seeking a qualified third party to conduct additional 
monitoring or from consulting with relevant governmental agencies, or 
from performing or having a third party perform monitoring. The Agency 
disagrees that decisions regarding monitoring of oil distribution and 
weathering are left up to the responsible party as the Clean Water Act 
and the NCP give the OSC clear authority to direct the responsible 
party during a response. The Agency also disagrees that the responsible 
party is the primary advisor for aspects of dispersant decision-making 
and monitoring. The monitoring requirements are intended to provide 
decision-makers, whose roles and responsibilities are described in the 
NCP, with relevant information to consider. The monitoring requirements 
do not prevent the OSC and other response decision-makers from 
considering monitoring information, including monitoring information 
collected by other entities besides the responsible party, to also be 
used to inform dispersant use decisions. While the final rule places 
the monitoring requirements on the responsible party, these 
requirements should not be interpreted or perceived as the responsible 
party directing the process or controlling how the dispersant 
effectiveness and dispersed oil fate data are interpreted. The Agency 
notes that the NCP already provides for natural resource trustee input 
for dispersant use as a response option under 40 CFR 300.910--
Authorization of Use, and Sec.  300.305(e)--Phase II--Preliminary 
assessment and initiation of action.

E. Ecological Characterization

    The new provisions include requirements for the responsible party 
to characterize the ecological receptors (e.g., aquatic species, 
wildlife, and/or other biological resources) and their habitats that 
may be present in the discharge area and their exposure pathways. As 
the OSC's oversight role over the responsible party is already 
established in the NCP, the Agency has removed the phrase ``in 
consultation with the OSC'' for Sec.  300.913(d) ecological 
characterization. As part of this characterization, the responsible 
party must include in this characterization those species that may be 
in sensitive life stages, transient or migratory species, breeding or 
breeding-related activities (e.g., embryo and larvae development), and 
threatened and/or endangered species that may be exposed to the oil 
that is not dispersed, the dispersed oil, and the dispersant alone. The 
responsible party must also estimate an acute toxicity level of concern 
for the dispersed oil using available dose/response information 
relevant to potentially exposed species.
    Several commenters agreed with EPA's proposed language requiring 
ecological characterization and the use of species sensitivity 
distributions and ecotoxicity benchmarks. These commenters emphasized 
that careful monitoring of biological receptors is important but 
commented that this should be done by independent scientists, and not 
by the responsible party because of conflict of interest. Another 
commenter generally supported the proposed additions to Sec.  
300.913(d). Another commenter stated that ecological characterizations 
should be done by scientists on behalf of local resource agencies, 
given that the required information can be complex and subtle, 
requiring expertise on seasonality, life cycles, habitat interactions, 
important and sensitive habitats, and other physical and biological 
factors that influence how ecosystem components respond to oil, 
dispersant, and dispersed oil.
    Some commenters offered amendments to this section. A commenter 
stated that EPA should require consultation with the DOI and Department 
of Commerce (DOC) natural resource trustees, not just the OSC, when 
developing ecological-receptor characterization. Another commenter 
stated that sensitive receptors and toxicity thresholds should be 
developed at a local/regional level based on the marine ecosystem, food 
web, abundance

[[Page 40257]]

of primary and secondary producers, and other factors that influence 
ecotoxicity, given significant variation throughout the United States.
    The Agency recognizes commenters' position that independent 
scientists conduct monitoring of biological receptors, rather than the 
responsible party, because of potential conflict of interest. The 
Agency notes that the NCP addresses the OSC's oversight role of the 
responsible party. The monitoring amendments in the final rule do not 
preclude the OSC from seeking independent parties to conduct additional 
monitoring, including from local, state and federal agencies. EPA 
agrees with concerns that the required information can be complex and 
subtle, requiring expertise on seasonality, life cycles, habitat 
interactions, important and sensitive habitats, and other physical and 
biological factors that influence how ecosystem components respond to 
oil, dispersant, and dispersed oil. Furthermore, the NCP provides for 
natural resource trustee input for dispersant use as a response option 
under 40 CFR 300.910--Authorization of Use, and Sec.  300.305(e)--Phase 
II--Preliminary assessment and initiation of action. Therefore, the 
Agency does not believe it is necessary for additional requirements 
under the monitoring section to recognize the role and responsibilities 
of natural resource trustees relative to the responsible party 
developing ecological-receptor characterization.
    The Agency agrees with commenters that sensitive receptors and 
toxicity thresholds should consider relevant local/regional factors. 
EPA agrees with commenters that the review of acute toxicity 
information should include actual toxicity test results of potentially 
exposed species in the area of the spill, but the Agency also 
recognizes that the use of a surrogate species when constructing the 
species sensitivity distribution (SSD) may be necessary if relevant 
toxicity data for site-specific species is unavailable.
    Some commenters stated that they support environmental monitoring 
that contributes to operational decision-making, but also stated that 
the required monitoring to determine possible environmental effects is 
too time consuming to support dispersant operations decisions and that 
conducting the required ecological characterization of the spill site 
may not be possible in the available response time frame. The 
commenters stated that if the untreated oil is likely to drift ashore 
and impact a sensitive coastal resource within a day or two unless it 
is dispersed, there will be a very finite period of time for such 
considerations suggested in the proposed rule. Another commenter agreed 
that monitoring to determine possible environmental effects is too time 
consuming and added that monitoring required to determine possible 
environmental effects is already accommodated within the existing 
Incident Command System (ICS) structure (e.g., wildlife team and the 
NRDA team). A commenter stated that while known ecological benchmarks 
may be constructive, it is not clear how exceedances of the thresholds 
would impact decision-making in practice. This commenter stated that 
requiring dispersant operations to stop due to a single-species 
exceedance may result in higher environmental damage overall. The 
commenter suggested that SSDs are a misuse of the method that is 
counter to establishing frameworks appropriate to dynamic ocean 
settings. The commenters stated that NEBA should be the basis to make 
operational decisions on whether dispersants and/or other agents should 
be used during a response.
    The Agency agrees with comments that support environmental 
monitoring as contributing to operational decision-making, but 
disagrees with the comment that monitoring to determine possible 
environmental effects is too time consuming to support dispersant 
operations decisions and that monitoring required to determine possible 
environmental effects is already accommodated within the existing ICS 
organizational structure (e.g., wildlife team and the NRDA team). A 
goal of NRDA is to compensate the public for losses to natural 
resources and resource services resulting from injury as a result of an 
oil discharge. While a NRDA team may be recognized in the ICS, it is 
independent of, and complementary to, the response action. The 
monitoring requirements are tailored to dispersant use and to inform 
response decision-making regarding that use, while other ICS 
organizations focus on general environmental effects of the response, 
not necessarily related to dispersant use. The Agency also disagrees 
that conducting the required ecological characterization of the spill 
site may not be possible in the available response time frame. The 
premise that untreated oil is likely to drift ashore and impact a 
sensitive coastal resource within a day or two unless it is dispersed 
implies that no other response options are available to prevent impacts 
to sensitive coastal resources and that these sensitive coastal 
resources are the sole response priority to consider in determining 
dispersant use. Dispersants are not the only option for oil spill 
response: Other response options may also prevent or lower overall 
environmental damage. When responding under the NCP, decisions on 
dispersants and/or other chemical agents made by the OSC and other 
federal agencies with roles and responsibilities under the NCP during a 
response are to be made in accordance with the NCP. While there is no 
prohibition on the use of environmental tradeoff methodologies, the use 
of such methodologies must be in conformance with the statutory and 
regulatory authorities that govern dispersant use. Furthermore, the 
Agency noted in the proposed rule (80 FR 3398) relevant sources of 
information (e.g., environmental assessments or statements, Federal and 
state environmental databases, ACP-Fish and Wildlife and Sensitive 
Environments Plan Annex; NOAA-Environmental Sensitivity Indices) that 
the responsible party may refer to in developing the characterization 
of ecological receptors. In addition, applicable facility or vessel 
response plans may also have relevant information. It is important to 
note that this final action is not requiring this information to be 
included in these planning documents, rather that these documents may 
serve as resources of relevant information. Finally, it is unclear how 
methodologies cited and supported by commenters evaluate environmental 
trade-offs for decision-making without the characterization of 
ecological receptors.
    Another commenter noted that the phrase ``but not be limited to'' 
should be added to a phrase in the proposal so the term ``include'' is 
not interpreted as limiting. ``The Agency believes that the ecological 
characterization should include, but not be limited to, those species 
that may be in sensitive life stages . . . .''
    The Agency acknowledges the commenter's suggestion that the phrase 
``but not be limited to'' be added to a phrase in the proposal so the 
term ``include'' is not interpreted to be limiting, so that the 
sentence reads: ``The Agency believes that the ecological 
characterization should include, but not be limited to, those species 
that may be in sensitive life stages . . .''. The Agency did not intend 
and does not believe that the term ``including'' is limiting. However, 
the Agency is modifying the sentence in the proposal to reflect this 
suggested change for clarity.
    A commenter stated that the regulation should specify that an 
invitation to participate, at least in a

[[Page 40258]]

consultation and review role, should be extended to the appropriate 
federal, state, and local authorities. A commenter stated that EPA 
should add to Sec.  300.913(d) that a DOI representative should 
participate in this process.
    Applicable Area Contingency Plans include input from relevant 
local, state, and federal agencies whose roles and responsibilities are 
identified in the NCP for the Area Committee. While the Agency did not 
propose to amend requirements for Area Contingency Planning and those 
requirements are outside the scope of this final action, EPA recognizes 
the Area Committee's role in ecological characterization as provided in 
the Fish and Wildlife and Sensitive Environments Plan in 40 CFR 
300.210(c)(4). The final rule does not prohibit the OSC from seeking 
input from the appropriate federal, state, and local authorities.
    A commenter asked EPA to clarify that toxicity monitoring is 
required following dispersant applications. Another commenter suggested 
the following revisions to EPA's approach to ecotoxicity benchmarks 
(EBs):
     The proposed approach will not fully characterize 
potential impacts on biological resources. Where EBs exist for these 
other hydrocarbon constituents, measured concentrations of those 
parameters need to be compared to these more specific toxicological 
benchmarks;
     The toxicity level should also include the dispersant 
since it has been found that dispersants alone are generally less toxic 
than oil, but that most dispersant and oil mixtures are more toxic than 
oil alone;
     The proposed approach to compare water concentrations with 
EBs for heavy metals and total petroleum hydrocarbon will not fully 
characterize potential impacts on biological resources;
     Examining only acute toxicity data does not capture the 
full effects of a spill, since it does not take into account indirect 
or sub-lethal effects, which could also alter populations and 
ecological communities;
     The review of acute toxicity information should include 
actual toxicity test results of potentially exposed species in the area 
of the spill, since the use of a surrogate species could vastly 
underestimate the actual toxicity of species in the area;
     EPA should calculate separate SSDs for unique 
environments;
     Toxicity testing using natural light will be important 
given the well documented phenomenon of photo-enhanced toxicity of 
certain oil constituents; and,
     The commenter expressed concern about EPA's approach to 
derive chronic toxicity benchmarks by applying safety factors to the 
acute toxicity EBs because the specific chemicals and toxicity 
mechanisms involved in acute toxicity are different from those involved 
in chronic toxicity.
    The proposed rule discussed an approach to monitor acute toxicity 
in the water column by comparing TPH concentrations in water samples to 
TPH-based EBs or to chronic toxicity benchmarks derived by applying a 
safety factor to the acute toxicity EBs. The Agency stated that SSDs, 
which allow for species relevant to the location of the discharge to be 
considered, could be developed for representative oils (e.g., crude 
oils) using existing acute toxicity values where sufficient species 
diversity are available. The Agency acknowledges that examining only 
acute toxicity data does not capture the full effects of a spill 
because it does not take into account indirect or sub-lethal effects. 
The Agency recognizes that specific chemicals and toxicity mechanisms 
involved in acute toxicity can be different from those involved in 
chronic toxicity. However, applying safety factors to the acute 
toxicity-based benchmarks to derive chronic benchmarks is not intended 
to discern toxicity mechanisms; rather it is intended to account for 
potential toxic impacts to relevant species. Furthermore, EPA 
recognizes that not all acute toxicity data is derived using similar 
exposure conditions and that SSDs should be calculated from acute 
toxicity data that reflects the site-specific exposure profiles. 
Finally, EPA recognizes the proposed approach does not fully 
characterize potential impacts on biological resources from other 
exposure mechanisms that may cause adverse impacts, such as oil 
smothering and coating.
    While the Agency did not propose to establish specific EB 
thresholds, EPA recognizes that EBs should be consistent with 
information in applicable ACPs. The Agency noted in the proposed rule 
that EBs could be computed from the fifth percentile of the SSD as the 
hazard concentration 5 percent (HC5), as they are considered protective 
of 95 percent of species, have been used by EPA for developing ambient 
water quality criteria, and are generally accepted by the international 
risk science community. For the reasons above, EPA disagrees with 
commenters who suggested that SSDs is counter to establishing 
frameworks appropriate to dynamic ocean settings. Furthermore, EPA is 
clarifying the final rule text to specify that acute toxicity levels of 
concern are determined using the SSD approach.
    EPA did not propose in the monitoring section that dispersant 
operations stop due to a single-species exceedance. However, EPA does 
not agree that stopping dispersant use over a single species exceedance 
will necessarily result in higher environmental damage overall. 
Dispersants are not the only available response tool, and other 
response options may also lower overall environmental damage. EPA 
believes that Congress' primary intent in regulating products (e.g., 
dispersants) under Subpart J is to protect the environment, including 
the water column, from possible deleterious effects caused by the 
application or use of these products. Decisions on the use of 
dispersants and other agents used during a response are to be made in 
accordance with the NCP and the governing statute(s). Environmental 
tradeoff methodologies where dispersants are considered must be in 
conformance with the statutory and regulatory authorities that govern 
dispersant use.

F. Immediate Reporting

    The new provisions require the responsible party to immediately 
report to the OSC and, in coordination with the OSC, to the RRT any: 
(1) Deviation of more than 10 percent from the mean hourly dispersant 
use rate for subsurface application, based on the dispersant volume 
authorized for 24 hours use, and the reason for the deviation; and (2) 
ecological receptors of environmental importance, and any other 
ecological receptors as designated by the OSC or the Natural Resource 
Trustees, including any threatened or endangered species that may be 
exposed based on dispersed plume trajectory modeling and level of 
concern information.
    Several commenters supported EPA's proposed immediate reporting 
provisions. Some commenters advocated for a 10 percent threshold for 
reporting deviations from the planned application rates for surface 
application in addition to subsurface application, while another 
commenter stated they do not support any subsurface application. A 
commenter stated that because the responsible party is already required 
to report hourly surface application rates on a daily basis under Sec.  
300.913(f), the commenter believes that adding a requirement for 
immediate reporting requirement in the case of deviations will add 
little, if any, marginal compliance costs.
    In this action, the Agency is not including a reporting requirement 
of a

[[Page 40259]]

10 percent deviation threshold for reporting requirement from the 
planned application rates for surface dispersant application. The 
Agency recognizes differences in the subsurface and surface application 
of dispersants. For a continuous discharge, subsurface applications may 
occur uninterrupted at relatively few discharge locations. Surface 
application is typically made by one or more aircraft which have a 
relatively limited capacity to apply dispersant over multiple oil 
patches. This limited capacity requires aircraft to refuel and 
resupply. While multiple aircraft may be used, deviations of surface 
dispersant application rate from a single aircraft are not expected to 
confound monitoring data interpretation in a similar manner as 10 
percent deviation from subsurface application. Furthermore, the Agency 
is requiring daily reports of the specific hourly dispersant 
application rate and total amount of dispersant used for surface 
application to monitor dispersant use activity. The daily reports will 
inform changes in surface dispersant application usage. Finally, the 
RIA does not include a compliance cost because the proposed provision 
addressing more than 10 percent deviation for surface applications is 
not being finalized.
    A commenter stated that all reports should simultaneously be made 
public. EPA recognizes the commenter's request that all reports should 
simultaneously be made public. While EPA shares the commenter's desire 
to make this information publicly available in a timely fashion, the 
Agency disagrees that this reporting should occur simultaneously with 
reporting to the OSC. Public communications authorities under the NCP 
are outside the scope of this action. The Agency notes that the OSC 
directs response efforts and coordinates all other efforts at the scene 
of a discharge in accordance with the NCP, including public information 
and community relations. The NCP provides instruction to the OSC on 
ensuring all appropriate public and private interests are kept informed 
and that their concerns are appropriately considered throughout a 
response. The Agency believes the OSC should be given the opportunity 
to evaluate response-related information and communicate relevant 
results to the public within the existing NCP framework.
    A commenter suggested that specifics required in Sec.  300.910(e) 
should be provided to the OSC and RRT. A commenter requested that any 
field observations of impacts to sensitive species be reported to the 
OSC and trustee agencies. This could include dispersant applications 
which inadvertently spray birds, marine mammals, sea turtles, or other 
sensitive species. While the commenter refers to Sec.  300.910(e), the 
Agency believes that the commenter intended to include Sec.  300.913(e) 
because the heading of the section to the comment referred to Sec.  
300.913(e-f). The Agency agrees that the RRT, which includes the 
natural resource trustees, should receive this information within the 
command structure of the National Response System (NRS). Working within 
the command structure provides an orderly and efficient review of 
monitoring and other response-related information by the OSC and allows 
the OSC to develop situational awareness and efficiently and 
effectively collaborate with agencies designated in the NCP that have 
relevant roles and responsibilities in the response. EPA has revised 
the regulatory language in the final rule by adding a new provision, 
Sec.  300.913(g), to provide that the responsible party must 
immediately report to the OSC and coordinate with the OSC to provide 
the applicable RRT(s) (including any incident-specific RRTs) with this 
information. The Agency notes that including the RRT(s) as recipients 
of the immediate reporting information addresses a commenter's request 
to include natural resource trustees.
    Some commenters stated that EPA should not develop requirements for 
daily authorizations of dispersant quantities. Another commenter also 
noted that the rule requires reporting based on deviations from 
authorized dispersant application in a 24-hour period, stating that EPA 
should not have daily authorizations for dispersant application because 
such restrictions would tremendously complicate dispersant operations 
and circumvent the NEBA process.
    EPA did not establish requirements on daily authorization of 
dispersant quantities in the final rule on the monitoring requirements. 
The Agency is establishing an immediate reporting provision in this 
final action to provide a margin for variation within 10 percent of the 
mean hourly subsurface dispersant application rate to account for 
equipment performance. The Agency believes this margin adequately 
accounts for variations in dispersant injection equipment without being 
overly restrictive. The intent of the requirement is for immediate 
reporting of more than 10 percent deviations for the subsurface 
dispersant application that were authorized during that reporting 
period. EPA did not intend to require, and Sec.  300.913(e) does not 
establish, that authorization is required in 24-hour increments. The 
OSC makes authorization of use decisions within the NCP framework. 
Authorization of use is outside the scope of the monitoring 
requirements in this final action. While an environmental trade-off 
framework may inform dispersant use, it is not required under the NCP. 
Results from daily water column sampling provide input data to refine 
predictions of the likely dispersed oil direction using trajectory 
modeling and may also inform decisions to alter dispersant application 
in order to minimize effects on ecological receptors, including 
biological resources.
    A commenter stated real-time ecological receptor analysis is 
unrealistic and should be part of a Consensus Ecological Risk 
Assessment (CERA)/NEBA process. Another commenter requested that any 
field observations of impacts to sensitive species be reported to the 
OSC and trustee agencies. The new monitoring requirements provide that 
the responsible party will characterize the ecological receptors (e.g., 
aquatic species, wildlife, and/or other biological resources), their 
habitats, and exposure pathways that may be present in the discharge 
area. The Agency understands that some ecological receptors are likely 
to be impacted and is clarifying that the immediate reporting 
requirement focuses on ecological receptors of environmental 
importance, as well as any other ecological receptors as identified by 
the OSC or the natural resource trustees, including threatened or 
endangered species that may be exposed to dispersed oil based on 
trajectory modeling and the estimated acute toxicity level of concern. 
EPA recognizes that the OSC or the natural resource trustees may also 
want to include critical habitats as applicable within the immediate 
reporting requirements for ecological receptors. The NCP already 
provides an existing organizational structure that allows the natural 
resource trustees to relay any requests they have regarding the 
monitoring requirements and resulting information to the OSC. The 
Agency is revising the regulatory language in the final rule to reflect 
this clarification. This revision also addresses a commenter's request 
to recognize prey species which these receptors depend upon for food 
that may be impacted by the discharge or the response.
    A commenter said the OSC should have discretion to determine the 
frequency of reporting and that the rule does not specify what happens 
if the reporting requirements are not met for any reason. The Agency 
recognizes that

[[Page 40260]]

the OSC may require other immediate notifications beyond those provided 
in the final rule and that the final rule provides a minimum set of 
immediate reporting criteria. Finally, the Agency notes that 
enforcement of regulatory provisions is outside the scope of the final 
rule. The final rule does not change any existing enforcement 
authorities.

G. Daily Reporting

    The new provisions require daily reporting by the responsible party 
to the OSC and to the RRT water sampling and data analyses collected in 
Sec.  300.913(b). These reports are to include: (1) For each 
application platform, the actual amount of dispersant used for each 
one-hour period, and the total amount of dispersant used for the 
previous 24-hour reporting period; (2) all collected data and analyses 
of those data within a time frame necessary to make operational 
decisions (e.g., within 24 hours of collection), including documented 
observations, photographs, video, and any other information related to 
dispersant use, unless an alternate time frame is authorized by the 
OSC; (3) for analyses that take more than 24 hours due to analytical 
methods, provide such data and results as available but no later than 5 
days after sample collection, unless an alternate time frame is 
authorized by the OSC; and (4) estimates of the daily transport of 
dispersed and non-dispersed oil and associated volatile petroleum 
hydrocarbons, and dispersants, using available technology as described 
in Sec.  300.913(c).
    Section 300.913(f)(1) of the final rule was altered to provide 
clarity. The text ``For each application platform, the . . .'' was 
added prior to the draft language, to ensure that the reporting would 
be for each platform, instead of the response as a whole. The term 
``application platform'' includes individual aircraft, vessels, and any 
other structures, devices, or other means that are used to apply 
dispersants. This section was also modified, replacing the term 
``actual dispersant application rate for each one-hour period'' with 
``the actual amount of dispersant used for each one-hour period''. This 
revision clarifies that the reported information must reflect the 
actual amount of dispersant applied each hour, rather than an hourly 
rate based on the total amount of dispersant applied averaged over a 
24-hour period. The requirement is intended to show hourly changes of 
the actual amount of dispersant used, which a calculated average hourly 
rate would not provide. This information will allow the OSC and RRT to 
better analyze if the application rates are at, below, or exceeding the 
authorized quantities, if dispersant use is per manufacturer's 
recommendations, and if the response actions are effective.
    EPA is also revising the regulatory text in the final rule to 
reflect that Sec.  300.913(c) changed ``. . . best available technology 
. . .'' to ``. . . considering available technologies . . .'' which 
includes trajectory modeling. See the Oil Distribution Analyses 
discussion in this preamble. The Agency is also revising the final rule 
text to include RRT as recipients of the daily reporting information 
for similar reasons as described in Immediate Reporting discussion in 
this preamble.
    Several commenters supported EPA's proposal to require daily 
reporting of sampling and data analyses within a time frame necessary 
for making sound operational decisions. However, a commenter stated 
that existing sampling and analytical methods might not provide 
complete or accurate information. They requested that EPA identify 
suggested methods or models that can accurately estimate the ``daily 
transport of dispersed and non-dispersed oil'' with sufficient accuracy 
to inform the coordination of monitoring activities.
    EPA acknowledges a commenter's concern that existing sampling and 
analytical methods might not provide complete or accurate information. 
However, the Agency believes existing sampling and analytical methods 
continue to improve and generally serve their intended purpose for 
decision-making during a response. The Agency recognizes that there may 
be other sampling and analytical methods used to inform other aspects 
of the response as a result of the oil discharge, such as those used in 
injury assessment that are conducted to support the NRDA process. 
Results from daily water column sampling conducted by the responsible 
party would provide input data to refine predictions of the likely 
dispersed oil direction using trajectory modeling. The daily reporting 
provisions requires the responsible party to report the estimated daily 
transport of dispersed and non-dispersed oil, associated volatile 
petroleum hydrocarbons if applicable, and dispersants, considering 
available technologies as described in Sec.  300.913(c). The Agency is 
not including suggested methods or models to estimate the ``daily 
transport of dispersed and non-dispersed oil.'' Rather, the Agency is 
establishing a framework in which the responsible party must identify 
sampling and analytical methods within a DMQAPP that provides the OSC 
and pertinent response agencies context for the collected data. This 
approach allows sampling and analytical methods to continue to advance 
without the need to periodically modify regulatory text to reflect any 
such advances. Finally, for analyses that take more than 24 hours due 
to analytical methods, the Agency is clarifying that the responsible 
party report data and results if it becomes available prior to the 5-
day period. Reporting results and data as soon as it becomes available 
avoids unnecessary delays in providing decision-makers, including 
relevant regulatory agencies, with timely information.
    A commenter noted that the requirements for daily reporting of 
water sampling data in Sec.  300.913(f) should only apply to subsea 
dispersant injection and are not useful for dispersant decision-making. 
The commenter stated that daily sampling and testing is arbitrary, 
overly burdensome, and unnecessary, suggesting that OSCs should have 
discretion in the frequency of sampling after the initial efficacy 
tests. Additionally, this commenter stated that the five day turnaround 
is unrealistic, given that it can take several days for sample 
transport and analysis. This commenter cited the quantity of samples 
and backlogs that resulted from the Deepwater Horizon response.
    EPA disagrees with the comment that stated daily reporting of water 
sampling data is not useful to dispersant decision-making, burdensome, 
or unrealistic given the experiences of the Deepwater Horizon oil 
spill. The final monitoring provisions require daily reporting of 
sampling and data analyses collected within the time frame necessary to 
make operational decisions unless an alternate time frame is authorized 
by the OSC. Additionally, a schedule is required for any data analyses 
that require time beyond 24 hours due to analytical methods; this 
schedule is not to exceed five days (i.e., 120 hours) unless authorized 
by the OSC. Timely sample analyses afford the OSC and other responders 
and decision makers with multiple relevant data that can be analyzed 
together to inform situational awareness of dispersant operations and 
adjust dispersant application as necessary. The Agency believes that a 
five-day window for analyses requiring additional time provides an 
adequate opportunity for the RP to arrange to conduct all requested 
analyses in a timely manner without being overly restrictive. The 
Agency believes the final rule provides flexibility for the OSC to 
provide an alternative time frame that is operationally relevant for

[[Page 40261]]

analyses that take more than 24 hours due to analytical methods.
    The Agency disagrees that daily water sampling and testing is 
burdensome and therefore also disagrees that only the OSC should 
determine the sampling frequency after initial efficacy tests. The 
Agency believes monitoring dispersant use in the field informs the OSC 
and response support agencies on its overall effectiveness, including 
potential environmental effects and transport of dispersed oil. Daily 
reporting serves to ensure information is received in a timely manner. 
The final rule provides notification for a responsible party to 
identify what analytical resources will be needed ahead of time rather 
than wait until an incident occurs to do so. A responsible party can 
also arrange for a schedule to prepare, transport, process, and analyze 
samples as part of response planning. The Agency believes that the 
responsible party can identify analytical processing resources (e.g., 
analytical laboratories) and arrange a sampling and processing schedule 
prior to any incident.
    The Agency disagrees that daily reporting of water sampling data 
should apply only to subsurface dispersant injection. Daily reporting 
of sampling data and other relevant information equally serves to 
inform surface dispersant application. The daily reporting requirement 
for collected data and analyses is necessary to make operational 
decisions, including documented observations, photographs, video, and 
any other information related to dispersant use, unless an alternate 
time frame is authorized by the OSC. While the responsible party shall 
provide data and results within five days, the final action provides 
flexibility to establish an alternate time frame authorized by the OSC 
for analyses that take more than 24 hours due to analytical methods.
    A commenter also suggested combining the Daily Reporting section 
with the Immediate Reporting section and included recommended language. 
EPA believes keeping these sections separate more clearly identifies 
the specific requirements within the two different time frames.
    Another commenter stated that EPA should make plans to protect 
worker health and public health required in ACPs along with already 
required plans to protect wildlife and to require daily public 
notification of product use, location, and quantity. The Agency notes 
that the NCP requires compliance with applicable worker health and 
safety regulations, including OSHA, under 40 CFR 300.150. Amendments to 
worker health and safety requirements under 40 CFR 300.150 and to Area 
Contingency Planning requirements under 40 CFR 300.210(c) are outside 
the scope of this final action on monitoring requirements. The Agency 
refers readers to the Immediate Reporting discussion where similar 
comments are addressed relative to public notification of dispersant-
related information for further analysis of this issue.

VI. Overview of New Rule Citations

    The Table below provides an overview of the new rule citations 
under 40 CFR part 300, subpart J, for a quick reference of the changes. 
New section, Sec.  300.913, Monitoring the Use of Dispersants, adds 
regulatory requirements for monitoring certain prolonged surface and 
subsurface use of dispersants.

                   Section 300.913 Distribution Table
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Sec.   300.913 Monitoring the Use of        General Applicability.
 Dispersants.
Sec.   300.913(a).........................  Information on Dispersant
                                             Application.
Sec.   300.913(b).........................  Water Column Sampling.
Sec.   300.913(c).........................  Oil Distribution Analyses.
Sec.   300.913(d).........................  Ecological Characterization.
Sec.   300.913(e).........................  Immediate Reporting.
Sec.   300.913(f).........................  Daily Reporting.
Sec.   300.913(g).........................  Immediate and Daily
                                             Reporting to RRTs.
------------------------------------------------------------------------

VII. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders 
can be found at https://www2.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is a significant regulatory action that was submitted 
to the Office of Management and Budget (OMB) for review. This action 
raises novel legal or policy issues arising out of legal mandates, the 
President's priorities, or the principles set forth in the Executive 
Order. Any changes made in response to OMB recommendations have been 
documented in the docket for this action. In addition, EPA prepared an 
analysis of the potential costs and benefits associated with this 
action. This analysis, ``Regulatory Impact Analysis, National Oil and 
Hazardous Substances Pollution Contingency Plan; Subpart J Monitoring 
Requirements'', is available in the docket for this action.

B. Paperwork Reduction Act (PRA)

    The information collection requirements in this final action have 
been submitted for approval to the Office of Management and Budget 
(OMB) under the PRA. The Information Collection Request (ICR) document 
prepared by EPA has been assigned EPA ICR No. 2675.01 (OMB Control No. 
2050-NEW). A copy of the ICR is provided in the docket for this rule 
and it is briefly summarized here. The monitoring provisions of the 
final rule include documentation of information about dispersant 
application; water sampling, oil distribution, and ecological 
characterization analysis; and, immediate and daily reporting.
    For this ICR, EPA has estimated an annualized cost for monitoring 
oil discharges for dispersants in the range of $32,000 to $3.0 million 
per year. This estimated range reflects the fact that costs can vary 
significantly depending upon the frequency, volume, duration, and 
location of oil discharges. EPA based its estimates on a range of oil 
discharge scenarios capturing different spill sources, volumes, and 
monitoring durations. The annual monitoring cost also reflects EPA's 
estimated applicable-discharge rate of 0.2 incidents per year, or one 
applicable discharge every five years, based on EPA's analysis of 
historical discharges.
    EPA has carefully considered the burden imposed upon the regulated 
community by the regulations. EPA believes that the activities required 
are necessary and, to the extent possible, has attempted to minimize 
the burden imposed. The minimum requirements specified in the final 
rule are intended to ensure that, when needed, product use is properly 
monitored in the field so that the oil discharge response is performed 
in a manner protective of human health and the environment.
    Respondents/affected entities: Oil discharge responsible parties.
    Respondent's obligation to respond: Mandatory (40 CFR part 300, 
subpart J).
    Estimated number of respondents: 0-1 per year.
    Frequency of response: 0.2 time per year.
    Total estimated cost: $32,000-$3,033,000 (per year for monitoring 
oil discharges).
    An agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for the 
EPA's regulations in 40 CFR are listed in 40 CFR part 9. When OMB 
approves this ICR, the Agency will announce that approval in the 
Federal

[[Page 40262]]

Register and publish a technical amendment to 40 CFR part 9 to display 
the OMB control number for the approved information collection 
activities contained in this final rule.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. In 
making this determination, the impact of concern is any significant 
adverse economic impact on small entities.
    EPA conducted a small business analysis consistent with the 
Agency's 2006 small business guidance. The Agency's analysis indicates 
that 9,527 affected entities are small businesses in the following 
industries: Crude Petroleum Extraction, Natural Gas Extraction, 
Petroleum Refineries, Petroleum Bulk Stations and Terminals, Natural 
Gas Extraction, Petroleum and Petroleum Products Merchant Wholesalers 
(except Bulk Stations and Terminals), Petroleum and Petroleum Products 
Merchant Wholesalers (except Bulk Stations and Terminals), Deep Sea 
Freight Transportation, Coastal and Great Lakes Freight Transportation, 
and Pipeline Transportation of Crude Oil.
    In conducting the small business analysis, the agency compared the 
incremental annualized compliance cost to the annual sales revenue for 
the smallest entities. The results indicate that if a small entity is 
responsible for a relatively large oil discharge, then the impact on 
that individual entity could be significant. However, there are 
important factors to consider when assessing the rule's overall effect 
on small businesses, including that historically, the RPs for 
applicable discharges are not very small entities, which constitute the 
vast majority of potential impacted entities in this analysis. In 
addition, the rarity of applicable discharges historically suggests 
that there will be only one entity affected by the rule (whether 
significantly or nonsignificantly) every five years, on average. For 
these reasons, EPA concludes that the final rule's requirements will 
not have a significant impact on a substantial number of small entities 
(SISNOSE). The small business analysis is available for review in the 
Regulatory Impact Analysis (RIA).

D. Unfunded Mandates Reform Act

    This action does not contain any unfunded mandate of $100 million 
or more as described in UMRA, 2 U.S.C. 1531-1538, and does not 
significantly or uniquely affect small governments. This final rule 
imposes no new enforceable duty on any state, local, or tribal 
governments or the private sector.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the States, on the relationship between 
the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    EPA has concluded that this action may have tribal implications 
because all tribes can be affected by oil spills and the subsequent use 
of oil spill mitigating agents, such as dispersants and bioremediation 
agents. However, this action will neither impose substantial direct 
compliance costs on tribal governments, nor preempt Tribal law, 
similarly to the effect on states.
    EPA consulted with tribal officials under EPA Policy on 
Consultation and Coordination with Indian Tribes early in the process 
of developing this regulation to enable them to have meaningful and 
timely input into its development. The NCP is the federal government's 
blueprint for responding to both oil spills and hazardous substance 
releases. Among other provisions, Subpart J of the NCP governs 
environmental monitoring of dispersants and other chemical agents to 
respond to oil spills in jurisdictional waters. Under the NCP, tribes 
are included in the definition of ``State'' found in 40 CFR 300.5 
except where specifically noted, and may participate as members of Area 
Committees, on RRTs, and on Tribal Emergency Response Commissions. See 
40 CFR 300.5.
    EPA's government-to-government consultation period occurred from 
March 11, 2015, to March 26, 2015, when EPA headquarters held five 
teleconference consultation events that informed tribes of the possible 
changes to the regulation as it was proposed in the Federal Register. 
Representatives from 10 tribes, tribal associations and organizations 
participated. During these calls, senior EPA staff fielded questions 
about the rulemaking as well as recorded comments and feedback. Tribal 
leaders and/or their delegated representatives raised questions about 
the use of dispersants and ensuring habitat and resource protection 
when responding to oil spills in Indian Country. EPA considered the 
input from these consultation calls and coordination activities, in 
conjunction with public comments, in the final rule development.
    In addition to consultation with tribes, EPA also conducted 
outreach to tribes over the two years before consultation. EPA staff 
participated in several tribal conferences and meetings where the 
proposed rulemaking was discussed, and information distributed to all 
participating tribes. Rulemaking outreach literature promoted awareness 
and coordination about the proposed regulation.
    As required by section 7(a), EPA's Tribal Consultation Official has 
certified that the requirements of the executive order have been met in 
a meaningful and timely manner. A copy of the certification is included 
in the docket for this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that concern environmental health or safety risks 
that EPA has reason to believe may disproportionately affect children, 
per the definition of ``covered regulatory action'' in section 2-202 of 
the Executive Order. This action is not subject to Executive Order 
13045 because it does not concern an environmental health risk or 
safety risk.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution or Use

    This action is not a ``significant energy action'' because it is 
not likely to have a significant adverse effect on the supply, 
distribution, or use of energy. The final rule focuses on monitoring 
requirements to address subsurface and certain surface applications of 
dispersants that meet applicability criteria specified by the final 
rule and minimizing potential adverse impacts from their use; thus, the 
rule will result in greater overall environmental protection. The final 
rule will not cause reductions in the supply or production of oil, 
fuel, coal, or electricity; nor will it result in increased energy 
prices, increased cost of energy distribution, or an increased 
dependence on foreign supplies of energy.

I. National Technology Transfer and Advancement Act

    This rulemaking does not involve technical standards.

J. Executive Order 12898: Environmental Justice (EJ)

    EPA believes that this action does not have disproportionately high 
and

[[Page 40263]]

adverse human health or environmental effects on minority populations, 
low-income populations, and/or indigenous peoples, as specified in 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    The documentation for this decision is contained in Regulatory 
Impact Analysis (RIA) for this action. This final rule is consistent 
with EPA's Environmental Justice Strategy and the Office of Land and 
Emergency Management (OLEM) Environmental Justice Action Agenda. To 
address the goals of the Strategy and the Agenda, EPA conducted a 
qualitative analysis of the environmental justice issues under this 
final rule.
    Historically, EPA has not found any evidence that the use of 
dispersant agents on oil discharges in the United States has had any 
disproportionate effect on any environmental justice communities. 
Moreover, the final rule is anticipated to improve the efficacy of 
dispersant application activities through monitoring requirements and 
thereby mitigate what could otherwise occur as adverse impacts from 
potentially less effective dispersant use. EPA will monitor the 
implementation of the rule to ensure the monitoring of dispersant 
agents has no disproportionate effect on any EJ communities.

K. Congressional Review Act (CRA)

    This action is subject to the CRA, and the EPA will submit a rule 
report to each House of the Congress and to the Comptroller General of 
the United States. This action is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

List of Subjects in 40 CFR Part 300

    Environmental protection, Area contingency planning, Chemical 
agents, Daily reporting, Dispersants, Hazardous Substances, 
Intergovernmental relations, Monitoring, Natural resources, Oil 
pollution, Oil spills, Oil spill mitigating devices, On-scene 
coordinator, Quality assurance, Regional response teams, Reporting and 
recordkeeping requirements, Responsible party.

    Dated: July 6, 2021.
Michael S. Regan,
Administrator.

    For the reasons set out in the preamble, the Environmental 
Protection Agency amends 40 CFR part 300 as follows:

PART 300--NATIONAL OIL AND HAZARDOUS SUBSTANCES POLLUTION 
CONTINGENCY PLAN

0
1. The authority citation for part 300 continues to read as follows:

    Authority: 33 U.S.C. 1251 et seq; 42 U.S.C. 9601-9657; E.O. 
13626, 77 FR 56749, 3 CFR, 2013 Comp., p. 306; E.O. 12777, 56 FR 
54757, 3 CFR, 1991 Comp., p. 351; E.O. 12580, 52 FR 2923, 3 CFR, 
1987 Comp., p. 193.

Subpart J--Use of Dispersants, and Other Chemicals

0
2. Add Sec.  300.913 to read as follows:


Sec.  300.913  Monitoring the use of dispersants.

    The responsible party shall monitor any subsurface use of 
dispersant in response to an oil discharge, any surface use of 
dispersant for more than 96 hours after initial application in response 
to an oil discharge, and any surface use of dispersant in response to 
oil discharges of more than 100,000 U.S. gallons occurring within a 24-
hour period, and shall submit a Dispersant Monitoring Quality Assurance 
Project Plan (DMQAPP) covering the collection of environmental data 
within this section to the OSC. When any dispersant is used subsurface 
in response to an oil discharge, the responsible party shall implement 
paragraphs (a) through (g) of this section for the entire duration of 
the subsurface dispersant use. When any dispersant is used on the 
surface in response to oil discharges of greater than 100,000 U.S. 
gallons occurring within a 24-hour period, the responsible party shall 
implement paragraphs (a) through (g) of this section as soon as 
possible for the entire or remaining duration of surface dispersant 
use, as applicable. When any dispersant is used on the surface in 
response to an oil discharge for more than 96 hours after initial 
application, the responsible party shall implement paragraphs (a) 
through (g) of this section for the remaining duration of surface 
dispersant use.
    (a) Document:
    (1) The characteristics of the source oil.
    (2) The best estimate of the oil discharge volume or flow rate, 
periodically reevaluated as conditions dictate, including a description 
of the method, associated uncertainties, and materials.
    (3) The dispersant used, rationale for dispersant choice(s) 
including the results of any efficacy and toxicity tests specific to 
area or site conditions, recommended dispersant-to-oil ratio (DOR).
    (4) The application method(s) and procedures, including a 
description of the equipment to be used, hourly application rates, 
capacities, and total amount of dispersant.
    (5) For subsurface discharges, the best estimate of the discharge 
flow rate of any associated volatile petroleum hydrocarbons, 
periodically reevaluated as conditions dictate, including a description 
of the method, associated uncertainties, and materials.
    (b) Collect a representative set of ambient background water column 
samples in areas not affected by the discharge of oil, at the closest 
safe distance from the discharge as determined by the OSC, and in all 
directions of likely oil transport considering surface and subsurface 
currents. Collect a representative set of baseline water column samples 
absent dispersant application at such depths and locations affected by 
the oil discharge, considering surface and subsurface currents, oil 
properties, and other relevant discharge conditions. On a daily basis, 
collect dispersed oil plume water column samples at such depths and 
locations where dispersed oil is likely to be present, considering 
surface and subsurface currents, oil properties, and other relevant 
discharge conditions. Collect these ambient background, baseline, and 
dispersed oil plume water column samples following standard operating 
and quality assurance procedures. Analyze the collected ambient 
background, baseline, and dispersed oil plume water column samples for:
    (1) In-situ oil droplet size distribution, including mass or volume 
mean diameter for droplet sizes ranging from 2.5 to 2,000 [mu]m, with 
the majority of data collected between the 2.5 and 100 [mu]m size.
    (2) In-situ fluorometry and fluorescence signatures targeted to the 
type of oil discharged and referenced against the source oil.
    (3) Dissolved oxygen (DO) (subsurface only).
    (4) Total petroleum hydrocarbons, individual resolvable 
constituents including volatile organic compounds, aliphatic 
hydrocarbons, monocyclic, polycyclic, and other aromatic hydrocarbons 
including alkylated homologs, and hopane and sterane biomarker 
compounds.
    (5) Methane, if present (subsurface only).
    (6) Heavy metals, including nickel and vanadium.
    (7) Turbidity.
    (8) Water temperature.
    (9) pH.
    (10) Conductivity.
    (c) Considering available technologies, characterize the dispersant 
effectiveness and oil distribution including trajectory, accounting for 
the condition of oil, dispersant, and dispersed oil components from the 
discharge location, and describing associated uncertainties.

[[Page 40264]]

    (d) Characterize the ecological receptors (e.g., aquatic species, 
wildlife, and/or other biological resources) and their habitats that 
may be present in the discharge area and their exposure pathways. The 
characterization shall include, but is not limited to, those species 
that may be in sensitive life stages, transient or migratory species, 
breeding or breeding-related activities (e.g., embryo and larvae 
development), and threatened and/or endangered species that may be 
exposed to the oil that is not dispersed, the dispersed oil, and the 
dispersant alone. The responsible party shall also estimate an acute 
toxicity level of concern for the dispersed oil using available dose-
response information relevant to potentially exposed species following 
a species sensitivity distribution.
    (e) Immediately report to the OSC any:
    (1) Deviation of more than 10 percent from the mean hourly 
dispersant use rate for subsurface application, based on the dispersant 
volume authorized for 24 hours use, and the reason for the deviation.
    (2) Ecological receptors of environmental importance, and any other 
ecological receptors as identified by the OSC or the Natural Resource 
Trustees, including any threatened or endangered species that may be 
exposed based on dispersed plume trajectory modeling and level of 
concern information.
    (f) Report daily to the OSC water sampling and data analyses 
collected in paragraph (b) of this section and include:
    (1) For each application platform, the actual amount of dispersant 
used for each one-hour period and the total amount of dispersant used 
for the previous 24-hour reporting period.
    (2) All collected data and analyses of those data within a time 
frame necessary to make operational decisions (e.g., within 24 hours of 
collection), including documented observations, photographs, video, and 
any other information related to dispersant use, unless an alternate 
time frame is authorized by the OSC.
    (3) For analyses that take more than 24 hours due to analytical 
methods, provide such data and results as available but no later than 
five days, unless an alternate time frame is authorized by the OSC.
    (4) Estimates of the daily transport of dispersed oil, non-
dispersed oil, the associated volatile petroleum hydrocarbons, and 
dispersants, using available technology as described in paragraph (c) 
of this section.
    (g) Report all information provided to the OSC under paragraphs (e) 
and (f) of this section to the applicable RRT(s).

[FR Doc. 2021-15122 Filed 7-26-21; 8:45 am]
BILLING CODE 6560-50-P