Current through Register Vol. 54, No. 44, November 2, 2024
(a)
The leachate detection zone shall meet the following performance standards. The
leachate detection zone shall:
(1) Rapidly
detect and collect liquid entering the leachate detection zone, and rapidly
transmit the liquid to the leachate treatment system.
(2) Withstand chemical attack from waste or
leachate.
(3) Withstand anticipated
loads, stresses and disturbances from overlying waste, waste cover materials
and equipment operation.
(4)
Function without clogging.
(5)
Prevent the liner from cracking, tearing, stretching or otherwise losing its
physical integrity.
(6) Cover the
bottom and sidewalls of the facility.
(b) Unless alternative design requirements to
meet the performance standards in subsection (a) are approved as part of the
permit under §
271.231 (relating to equivalency
review procedure), the leachate detection zone of a liner system shall meet the
following design requirements:
(1) Be at least
12 inches thick.
(2) Contain no
material exceeding 0.5 inches in particle size.
(3) Create a flow zone between the subbase
and the liner more permeable than 1 x 10-2 cm./sec.
based on laboratory testing and, when required by the Department, field
testing.
(4) Contain a perforated
piping system capable of detecting and intercepting liquid within the leachate
detection zone and conveying the liquid to a collection sump for storage,
processing or disposal. The sump shall be separate from the leachate collection
sump and shall be of a sufficient size to transmit leachate that is generated.
The piping system shall also meet the following:
(i) The slope, size and spacing of the piping
system shall assure that liquids drain from the leachate detection
zone.
(ii) The pipes shall be
installed primarily perpendicular to the flow and shall have a minimum
postsettlement grade of at least 2%.
(iii) The minimum diameter of the perforated
pipe shall be 4 inches with a wall thickness of Schedule-80 or greater as
specified by ASTM or equivalent.
(iv) The pipes shall be cleaned and
maintained as necessary.
(5) The leachate detection zone shall have a
minimum bottom slope of 2%.
(6)
Contain stone or aggregates without sharp edges.
(c) The operator shall monitor the leachate
detection zone weekly to determine whether liquid is flowing from the
zone.
(d) If liquid is flowing from
the leachate detection zone the operator shall:
(1) Immediately notify the Department in
writing.
(2) Estimate, on a weekly
basis, the volume of liquid flowing from the zone.
(3) Sample and analyze the liquid, on a
quarterly basis, for pH, specific conductivity, total organic carbon and
chlorides. The Department may also require sampling and analyses for other
constituents expected to be found in the waste.
(4) Provide written copies of the flow and
analysis data to the Department.
(e) If leachate flow is greater than 100
gallons per acre of lined collection area per day or more than 10% of leachate
generation, the operator shall:
(1) Submit to
the Department a plan within 30 days for locating the source of leachate in the
leachate detection zone, and for determining the severity and cause of leachate
penetration.
(2) Implement the plan
upon Department approval, and complete the plan in a reasonable time not to
exceed 6 months.
(3) Submit to the
Department, within 45 days after completion of the plan, a report containing
the new data collected, analysis of the data and recommendations concerning a
remedial plan.
(4) Conduct
quarterly sampling and analysis for the parameters in §
277.284(1)
(relating to sampling and analysis), and submit copies of the results of the
analysis to the Department.
(f) If sampling results indicate the presence
of constituents at concentrations that could result in degradation of
groundwater, the operator shall:
(1) Submit to
the Department a remedial plan for controlling the source of leachate in the
leachate detection zone, and implement the plan upon Department
approval.
(2) Submit to the
Department a permit modification application under §
271.222 (relating to permit
modification) for increased groundwater monitoring, giving consideration to
monitoring frequency, number of wells and other factors, and conduct increased
groundwater monitoring upon Department approval of the
application.
This section cited in 25 Pa. Code §
277.161 (relating to liner system
and leachate control plan); 25 Pa. Code §
277.164 (relating to application
requirements for noncoal mine disposal); 25 Pa. Code §
277.251 (relating to scope and
requirements); and 25 Pa. Code §
277.282 (relating to number,
location and depth of monitoring
points).
