(1)
Purpose and
Scope. 310 CMR 40.1025 specifies requirements for an Active
Exposure Pathway Mitigation Measure Implemented as part of a Permanent Solution
with Conditions.
(2)
Demonstration of Effectiveness. An Active Exposure
Pathway Mitigation Measure implemented as part of a Permanent Solution with
Conditions shall be designed and demonstrated to eliminate exposure to OHM to
the extent feasible and ensure, at a minimum, that a condition of No
Significant Risk is achieved and maintained for the Receptor(s) of concern.
Demonstration of the effectiveness of Active Exposure Pathway Mitigation
Measure shall be made prior to the achievement of a Permanent Solution with
Conditions and shall be based on the measurement of Exposure Point
Concentrations representative of exposures for the Receptor(s) of concern
during operation of the Active Exposure Pathway Mitigation Measure under normal
operating conditions and over a period of time sufficient to account for
temporal variability.
(3)
Operation of an Active Exposure Pathway Mitigation Measure
Implemented as Part of a Permanent Solution with Conditions.
(a) The necessity of operating and
maintaining the Active Exposure Pathway Mitigation Measure according to the
operating regimen documented in the Permanent Solution Statement shall be
specified in an Activity and Use Limitation recorded on the deed of the
property where the Active Exposure Pathway Mitigation Measure is located that
includes the requirements of 310 CMR 40.1025 as terms and conditions for
maintaining a Permanent Solution;
(b) The operating regimen for the Active
Exposure Pathway Mitigation Measure documented in the Permanent Solution
Statement shall be designed to ensure a level of No Significant Risk is
maintained for the Receptor(s) of concern under normal operating
conditions;
(c) The operating
regimen shall document the parameters for operating the Active Exposure Pathway
Mitigation Measure and the methods and frequency for monitoring such Measure to
ensure that it is operating consistently within such parameters as specified at
310 CMR 40.1025(3)(d) and (e), as applicable;
(d) The operating regimen for an Active
Exposure Pathway Mitigation Measure installed to prevent the migration of
subsurface OHM vapors into a building shall:
1. for an Active Exposure Pathway Mitigation
Measure installed to prevent the migration of subsurface OHM vapors into a
building by creating and maintaining a negative pressure field beneath a
building;
a. establish the acceptable vacuum
range to maintain an appropriate negative pressure field beneath a building for
each area or zone of soil gas extraction serviced by a discrete fan or blower;
and
b. continuously monitor the
vacuum level at each area or zone of soil gas extraction serviced by a discrete
fan or blower;
2. for an
Active Exposure Pathway Mitigation Measure installed to prevent the migration
of subsurface OHM vapors into a building by creating and maintaining a positive
pressure field within the building's living and working space:
a. establish the acceptable operating range
to maintain a positive pressure field within the building's living and working
space; and
b. continuously monitor
and continuously transmit the pressure level at each monitoring point to a
website that meets Department specifications pursuant to 310 CMR
40.1025(3)(d)5;
3. employ
remote monitoring technology that will immediately send an alert to the owner
and operator of the building protected by the Active Exposure Pathway
Mitigation Measure and the Department when the vacuum level (or pressure level,
where applicable) is outside the acceptable range and when such level returns
within the acceptable range;
4.
register the remote monitoring device as specified in
310
CMR 40.1027 prior to the achievement of a
Permanent Solution that relies upon the operation of an Active Exposure Pathway
Mitigation Measure to eliminate or mitigate the migration of subsurface OHM
vapors into a building;
5. for an
Active Exposure Pathway Mitigation Measure installed to prevent the migration
of subsurface OHM vapors into a building by creating and maintaining a positive
pressure field within the building's living and working space, require written
confirmation by the Department of a remote monitoring system which continuously
monitors and continuously transmits key operational data of the Active Exposure
Pathway Mitigation Measure to a website that meets Department specifications as
specified at
310
CMR 40.1027 and
310
CMR 40.1027(2)(c);
and
6. for Permanent Solutions with
Conditions implemented pursuant to 310 CMR 40.1025 prior to March 1, 2024, be
such that the alerts required pursuant to 310 CMR 40.1025(3)(d)3. may be
triggered by the monitoring of either vacuum level as described in 310 CMR
40.1025(3)(d)3. or the shutdown and restart of soil gas extraction
system;
(e) The operating
regimen of an Active Exposure Pathway Mitigation Measure implemented as part of
a Permanent Solution with Conditions that is installed to remove OHM from
drinking water supplied by a private water supply well shall:
1. provide a schedule for the Active Exposure
Pathway Mitigation Measure that specifies the frequency and activities for
inspecting and maintaining and replacing or recharging media employed for OHM
removal. Such frequency shall be based on a conservative estimate of the
system's performance (i.e., estimated breakthrough time) and
demonstrated to be adequate by confirmatory testing;
2. establish proper disposal procedures for
any spent media generated as a result of operation of the Active Exposure
Pathway Mitigation Measure; and
3.
require the maintenance of records documenting all activities to maintain the
system, including replacing, recharging, removing or disposing of spent media,
and the results of confirmatory testing of drinking water samples.
(f) The operating regimen shall
document the longest duration of a shutdown that would be consistent with:
1. a level of exposure that does not pose an
Imminent Hazard; and
2. a level of
exposure that poses No Significant Risk; and
(g) Following submittal of a Permanent
Solution Statement, the Active Exposure Pathway Mitigation Measure shall be
consistently operated and maintained at a level of effectiveness that ensures a
level of No Significant Risk is maintained for the Receptor(s) of concern and
in accordance with the provisions of 310 CMR 40.1025.
(h) The submittal of Remedial Monitoring
Reports and Status Reports are not required for the operation of an Active
Exposure Pathway Mitigation Measure implemented as part of a Permanent Solution
after the Permanent Solution Statement has been submitted to the
Department.
(4) The owner
of a property where an Active Exposure Pathway Mitigation Measure operating
pursuant to 310 CMR 40.1025 that has received written confirmation from the
Department pursuant to
310
CMR 40.1027 of a completed registration of a
remote monitoring system which continuously monitors and continuously transmits
key operational data of the Active Exposure Pathway Mitigation Measure to a
website that meets Department specifications and is operating the AEPMM in a
manner consistent with the operating regimen to eliminate or mitigate the
migration of OHM vapors into a building shall not be subject to the requirement
of 310 CMR 40.1025(9).
(5) An
Active Exposure Pathway Mitigation Measure shall not be used to support a
Permanent Solution with Conditions if suspension or failure of such measure
lasting 60 or fewer consecutive days would result in a Receptor exposure to OHM
concentrations that would pose an Imminent Hazard.
(6) An Active Exposure Pathway Mitigation
Measure shall not be used to support a Permanent Solution with Conditions
unless the owner of the property where the Active Exposure Pathway Mitigation
Measure is located certifies at the time that the Permanent Solution with
Conditions is implemented that financial resources have been made available for
the immediate repair and/or replacement of components of the Active Exposure
Pathway Mitigation Measure in the event that the Measure experiences
failure.
(7) In the event of any
suspension or failure of an Active Exposure Pathway Mitigation Measure
implemented as part of a Permanent Solution with Conditions, the owner of the
property where the Active Exposure Pathway Mitigation Measure is located shall
undertake immediate steps to return the Active Exposure Pathway Mitigation
Measure to full operating condition. If such suspension or failure of the
system lasts 30 or more consecutive days, the owner of the property where such
Measure is located shall notify both the Department and any non-transient
occupants of the building protected by such Measure who may have experienced
exposure to oil and/or hazardous material as the result of the system
suspension or failure on the 30th day from the start
of the suspension or failure period. This notice shall document the reason for
the suspension or failure of the Active Exposure Pathway Mitigation Measure,
any efforts made or steps to be taken to resume operation of such Measure, and
the expected timeframe for resuming operation of such Measure.
(8) The owner of the property where an Active
Exposure Pathway Mitigation Measure is implemented as part of a Permanent
Solution with Conditions shall annually certify in response to receipt of a
form provided by the Department that:
(a) the
property owner is aware of his or her obligation to operate and maintain the
Active Exposure Pathway Mitigation Measure, including repairing or replacing
components of the Measure to resume operation in the event the Measure
experiences suspension or failure;
(b) the property owner is aware of his or her
obligation to notify both the Department and any non-transient occupants of the
building protected by the Active Exposure Pathway Mitigation Measure if
suspension or failure of the system lasts 30 or more consecutive days;
(c) the property owner is aware
that the Department may upon reasonable notice inspect the Active Exposure
Pathway Mitigation Measure to ensure that it is operating pursuant to the
regimen established at 310 CMR 40.1025;
(d) financial resources are available to the
property owner for the immediate repair and/or replacement of components of the
Active Exposure Pathway Mitigation Measure in the event that the Measure
experiences failure; and
(e) the
Active Exposure Pathway Mitigation Measure is operating pursuant to the regimen
established at 310 CMR 40.1025.
(9) Except as provided pursuant to 310 CMR
40.1025(4), the owner of the property where an Active Exposure Pathway
Mitigation Measure is implemented as part of a Permanent Solution with
Conditions to prevent the migration of subsurface vapors into a building shall
conduct a shutdown and restart test to demonstrate remote monitoring technology
is operational in response to a written request by the Department.
(10) Where a Permanent Solution with
Conditions is based upon the operation of an Active Exposure Pathway Mitigation
Measure, the operation of such a measure may be terminated following
documentation provided in a revised Permanent Solution Statement pursuant to
310
CMR 40.1000 that the measure is no longer
necessary to maintain a Permanent Solution. Such documentation shall include a
Risk Characterization conducted pursuant to
310
CMR 40.0900 that evaluates and documents
exposure to OHM for Receptor(s) of concern in the absence of the Active
Exposure Pathway Mitigation Measure over a period of time sufficient to account
for temporal variability and supports a conclusion that a condition of No
Significant Risk exists in the absence of such Measure.
