Current through Register Vol. 35, No. 6, March 26, 2024
A. If approved by the department, owners and
operators shall submit a plan for monitored natural attenuation to the
department if any of the following conditions have been identified at the site:
(1) concentrations of contaminants of concern
exceed site-specific target levels (SSTLs) in soil or WQCC or EIB standards in
groundwater or surface water; or
(2) other conditions exist as a result of the
release which threaten public health, safety and welfare or the environment, as
determined by the department.
B. Owners and operators shall submit the
monitored natural attenuation plan in accordance with this section and
20.5.119.1920 NMAC and in accordance with a timeline approved by the department
or the timeline set forth in Subsection E of 20.5.119.1900 NMAC.
C. The intent of the monitored natural
attenuation plan is to provide a written description of the methodology
proposed and demonstrate how the plan will achieve target concentrations in a
manner that is practicable, cost effective, and protective of public health,
safety and welfare and the environment. The content of the monitored natural
attenuation plan, at a minimum and as appropriate, shall include:
(1) a site plan drawn to scale of no less
than one inch equals 40 feet, showing all existing buildings, structures, paved
areas, utilities, buried utility trenches, former and existing petroleum
storage tanks and ancillary equipment, other sources of contamination, extent
and magnitude of contamination, and existing and proposed monitoring
wells;
(2) cross sections showing
the source contaminant mass in relation to the groundwater
contamination;
(3) a topographic
map of appropriate scale showing the site in relation to existing and
reasonably foreseeable future receptors;
(4) concentration contour maps depicting the
extent and magnitude of the contaminants of concern and the designated
monitoring wells in relation to the site;
(5) a schematic drawing depicting the
construction details including lithology and screen intervals for the
designated monitoring wells;
(6)
the justification for selecting the designated monitoring wells;
(7) the recommended approach to monitoring
including an implementation and monitoring schedule, the analytical methods,
and the justification for the recommendation;
(8) an estimation of the time necessary for
achieving target concentrations, and a demonstration through calculations or
other appropriate means which supports this schedule;
(9) a contingency plan in case of a change in
site conditions that threatens public health, safety and welfare or the
environment;
(10) public notice in
conformance with the following requirements:
(a) owners and operators shall publish a
legal notice of the submission or planned submission of the monitored natural
attenuation plan at least twice in a paper of general circulation in the county
in which soil or water has been contaminated by the release; the first notice
shall appear within one week of, but not later than, the day of submission of
the monitored natural attenuation plan to the department; the second
publication of this notice shall occur no later than seven days after the date
the monitored natural attenuation plan is submitted to the department, and
owners and operators shall submit two certified affidavits of publication from
the newspaper to the department within 21 days after the date the monitored
natural attenuation plan is submitted;
(b) the notice shall contain the information
specified in this section including the following:
(i) a statement that a monitored natural
attenuation plan has been submitted to the department proposing actions to
monitor natural attenuation of a release of petroleum products;
(ii) the name and physical address of the
site at which the release occurred and the names and physical addresses of
properties where any part of contaminant plume is located, using adequate
identification of the properties, including street addresses if
applicable;
(iii) a statement that
a copy of the monitored natural attenuation plan and all data and modeling
related to the monitored natural attenuation plan, if applicable, can be viewed
at the department's main office and at the department's field office for the
area in which the release occurred; and
(iv) a statement that public comments on the
plan must be delivered within 21 days of the publication of the second notice,
to the owner or operator's assigned project manager at the petroleum storage
tank bureau, New Mexico environment department, or a district office if
approved by the department, and to the secretary of the environment
department;
(c) within
seven days of the date a monitored natural attenuation plan is submitted to the
department, owners and operators shall also mail by certified mail a copy of
the legal notice to adjacent property owners; and
(d) owners and operators shall post a notice
of the submission of the monitored natural attenuation plan at the release site
within seven days of the submission of the monitored natural attenuation plan;
the notice shall contain the information specified in this subsection and shall
be at least eight and one-half inches by 11 inches in size and prominently
displayed in a location where it is likely to be seen by members of the public
for a continuous period until the monitored natural attenuation plan is
approved and implemented; public comments must be received by the department
within 21 days of the date of the second publication of the public notice;
and
(11) other
requirements as directed by the department.