Erosion and Sediment Pollution Control Program Manual.pdf

NPDES Permits Involving Site Remediation and Redevelopment.
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In general, the risk of discharge will be directly related to the
level of contamination at the site. General permits are
ineligible for sites having the potential to discharge
contaminants. In most cases, individual NPDES permits will
be required to facilitate coordinated reviews with pertinent
Department staff and to apply the additional level of review
that may be necessary. Sites that have already been
remediated to the Residential Statewide Health Standard for
soils and groundwater are not considered to be
contaminated and a general permit (PAG-02) can be
authorized for earth disturbance activities on such sites.
Persons applying for an NPDES Permit for stormwater discharges associated with construction
activities are required to employ environmental due diligence to determine if past and present land use
may have resulted in the possibility of contamination on site. Examples of environmental due diligence,
include but are not limited to:
Determining previous uses of the land, or of any neighboring land.
Determining if the site has the potential to be contaminated based on past activities.
Checking with local government entities for any information that may be available about the
area.
Contacting agencies that may have dealings with contaminated sites and gathering any
available information for the site in question.
Performing a site inspection/investigation by an experienced practitioner since the level of risk
can only be assessed on a site-by-site basis. Note, this may be the same as performing a site
characterization.
If there is a possibility of soil and/or groundwater contamination, the applicant is required to have
testing performed and to provide the sampling and test results in the appropriate section of the NPDES
permit. The applicant should not refer to a lengthy site characterization/remediation plan that was
submitted to a separate Department program, but rather submit a summary of all the pollutants of
concern on a table and provide brief supporting documentation as necessary. In particular, information
should be submitted regarding the potential of contaminant mobility due to proposed construction
activities.
Based on the aforementioned, the following minimum information is required for projects involving
potential pollutants on-site, including the Land Recycling Program under Act 2 of 1995, Superfund
program or any other project involving site remediation and/or redevelopment.
1. Site Plan:
a. The existing site plan should clearly show all areas that have been tested and which of
those areas have been identified as “contaminated,” or are considered “hot spots.” For
Act 2 sites, this would include all areas that do not meet the statewide residential health
standard. More discussion on dealing with hot spot areas can be found in Appendix C of
the Pennsylvania Stormwater Best Management Practices Manual.
b. For those projects involving redevelopment, the proposed site plan and narrative should
clearly show any remaining contaminated areas, including areas that were capped, that
may be exposed as a result of the proposed work and explain how any conflicts have
been resolved, including:
i. The placement of utilities, foundations or other subsurface systems that may
compromise the clean-up remedy.
363-2134-008 / March 31, 2012 / Page 340