2017 Annual Report of the Delaware River Basin Commission

Reducing PCBs in the Estuary
The Development of
Stage 2 TMDLs
More than a decade ago, the U.S. Environmental
Protection Agency (EPA), on behalf of the states
of New Jersey, Pennsylvania and Delaware,
established acceptable loads (called Total
Maximum Daily Loads or TMDLs) for polychlorinated
biphenyls (PCBs) for the Delaware River Estuary.
These TMDLs were developed by the Commission
and are designed to protect human health
from the carcinogenic effects of eating contaminated
fish caught in these waters. These are
referred to as Stage 1 TMDLs.
Implementation of these TMDLs led by the
Commission has, to date, dramatically reduced
PCB loading from point sources. Between 2005
and 2016, a 76-percent reduction in total PCBs
was observed for the top ten dischargers.
Despite the progress made by point source
dischargers, PCB loading reductions from nonpoint
sources, including contaminated sites, are
needed to achieve the proposed Stage 2 TMDLs.
The establishment of these TMDLs sets forth a
framework and specific goals to continue the longterm
effort required to protect human health and
restore the health of the Delaware Estuary and
Bay. Due to the scope and complexity of the problem
that has been defined through development
of both the Stage 1 and 2 TMDLs, achieving the
estuary water quality standards for PCBs will
require continued efforts by the point source
dischargers and focused efforts on the various non
-point source categories, particularly contaminated
sites.
What Are PCBs?
The Commission continues to work with EPA’s
Regions II and III to develop updated TMDLs.
These are referred to as Stage 2 TMDLs, which
will:
• Account for new water quality criteria for
PCBs adopted by the Commission in 2013;
• Use a more equitable allocation procedure for
wasteload allocations for point sources
selected through a stakeholder process led by
the Commission; and
• Enhance the implementation strategy to maintain
the PCB reductions achieved by point
sources, as well as continue the progress in
the reduction of PCBs for all sources.
Polychlorinated biphenyls (PCBs) are man-made
organic chemicals that were widely used in
electrical equipment including capacitors, transformers
and switches; paints, hydraulic fluids and
plasticizers.
• Hydrophobic and persistent, PCBs accumulate
in sediments and fish tissues.
• PCBs have been identified as a possible human
carcinogen.
22 VALUE
THROUGHOUT THE YEAR
• Manufacture of PCBs was banned in the U.S. in
1979. However, use continues in existing
applications.