(1)
Purpose and
Scope. 310 CMR 40.1026 specifies requirements for an Active
Exposure Pathway Mitigation Measure implemented as part of a Temporary Solution
or Remedy Operation Status.
(2)
Demonstration of Effectiveness. An Active Exposure
Pathway Mitigation Measure implemented as part of a Temporary Solution or
Remedy Operation Status 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 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
Temporary Solution or Remedy Operation Status.
(a) The operating regimen for the Active
Exposure Pathway Mitigation Measure implemented as part of a Temporary Solution
or Remedy Operation Status shall be specified in Temporary Solution Statement
or Phase IV Operation, Maintenance and Monitoring Plan developed as part of the
Remedy Implementation Plan, respectively;
(b) The operating regimen for the Active
Exposure Pathway Mitigation Measure 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;
(d) The operating
regimen for an Active Exposure Pathway Mitigation Measure installed to
eliminate or mitigate 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
40.1026(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
Temporary Solution or Remedy Operation Status that relies upon the operation of
an Active Exposure Pathway Mitigation Measure to prevent 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);
6. for an Active Exposure Pathway Mitigation
Measure installed to prevent the migration of subsurface OHM vapors into a
building implemented as part of a Temporary Solution or Remedy Operation Status
pursuant to 310 CMR 40.1026 prior to March 1, 2024, be such that the alerts
required pursuant to 310 CMR 40.1026(3)(d)3. may be triggered by the monitoring
of either vacuum level as described in 310 CMR 40.1026(3)(d)3. or the shutdown
and restart of soil gas extraction system; and
7. notwithstanding 310 CMR 40.1026(3)(d)6.,
Active Exposure Pathway Elimination Measures initially implemented pursuant to
310 CMR 40.1026 must meet the requirements of
310
CMR 40.1025, including the monitoring
requirements at
310
CMR 40.1025(3)(d), prior to
such system being used to support a Permanent Solution.
(e) The operating regimen of an Active
Exposure Pathway Mitigation Measure implemented as part of a Temporary Solution
or Remedy Operation Status 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 Temporary
Solution Statement or Remedy Operation Status, 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
Receptors of concern and in accordance with the provisions of 310 CMR
40.1026.
(4) The owner of
a property where an Active Exposure Pathway Mitigation Measure operating
pursuant to 310 CMR 40.1026 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 required to submit
Remedial Monitoring Reports for such AEPMMs.
(5) In the event of any suspension or failure
of an Active Exposure Pathway Mitigation Measure implemented as part of a
Temporary Solution or Remedy Operation Status, 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.
(6) Notwithstanding
310
CMR 40.0893(6)(c), any
person who intends to discontinue an Active Exposure Pathway Mitigation Measure
implemented as part of a Temporary Solution or Remedy Operation Status in order
to assess whether the remedial goals have been achieved and conditions remain
stable over time may maintain such Temporary Solution or Remedy Operation
Status provided that he or she:
(a) notifies
the Department of the system shutdown for the purpose of such evaluation and
the plans for monitoring site conditions in the next required Status Report
following system shut down;
(b)
continues to submit Status Reports at the frequency required in
310
CMR 40.0898 or
310
CMR 40.0892, respectively;
(c) notifies the Department if operation of
the Active Exposure Pathway Mitigation Measure is resumed in the next required
Status Report following resumed operation; and
(d) notifies the appropriate persons in
accordance with 310 CMR 40.1026(5), if the shutdown lasts 30 or more
consecutive days.
(7)
Except as provided at 310 CMR 40.1026(4), an Active Exposure Pathway Mitigation
Measure implemented as part of a Temporary Solution or Remedy Operation Status
shall require a Remedial Monitoring Report to be submitted in accordance with
310
CMR 40.0027.
