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Stormwater Sampling and Discharge System –
Post-Construction
(August 27, 2010 to present)
A Final Inspection was conducted at the Marjol Battery Site on August 31,
2010. Based on the inspection, construction of the Final Remedy was determined
to be “substantially complete” as of August 27, 2010, and the site is in the
post-construction period. All lead-contaminated material at the Site is
consolidated in the Containment (cap) Area (CA) and has been covered by the
multiple layers of cap materials, so all surfaces of the Site are clean (average
lead levels below 500 mg/kg). (Click here for a drawing showing the layers of
the cap.)
Stormwater management post-construction is slightly different than
stormwater management during construction since the lead-contaminated
materials are secure under the cap and there is no longer a concern about a
release of lead from the site.
(For more information on Stormwater
Management During Construction, click here.) There is no longer a separate
area for handling water that came into contact with the lead-contaminated
materials and all runoff flows to the basin. There is still the need to
control sediment, however, until the grassy vegetation is established in the
areas that were disturbed by construction activities. In order to keep as
much sediment as possible on the site, the stormwater management system at
the Site was designed so that sediment that is carried along with stormwater
would settle out in the sedimentation basin before discharging into Sulphur
Creek via the skimmer.
In
addition to being part of the 100% Design Plan for the Site, the
stormwater management system at the Marjol Battery Site is
maintained and monitored under a permit (NPDES permit) issued by the
State of Pennsylvania (Gould Electronics Inc. and SCE Environmental
are co-permittees on the NPDES permit for the Site.) The 100% Design
Plan called for stormwater discharge monitoring from the Site to be
discontinued at the end of construction because at that point the
potential for lead to be discharged from the Site was removed. The
state permit for the Site will however, remain active until
vegetation is established at the Site,
In
November, 2010, Gould sent a letter to PADEP requesting information
on the requirements for sediment basin discharge management under
the NPDES permit. In PADEP’s response
(Click here to review PADEP’s response letter.), it stated that
stormwater discharge monitoring is not required on “non-working”
(days when there is no earth moving activities). Gould has elected
to continue to test for total and dissolved lead on a monthly basis,
even though the potential for lead contamination had been removed
once the remedy was complete. Turbidity monitoring will only occur
when the basin is discharging while earth moving activities are
taking place. Once vegetation at the Site is established, the
amount of soil particles being washed away in stormwater should be
much less and therefore the potential for turbid discharge should be
substantially decreased.
(Click here to go back to the
Stormwater Management System page.)
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