Magnolia Avenue Ground Water Contamination
Wall Township & Sea Girt & Manasquan Boroughs, Monmouth County
PI #: G000037452
BLOCK: Various LOT: Various
Community Relations Coordinator: Heather Swartz (609) 984-7135
SITE DESCRIPTION/RESOLUTION OF ENVIRONMENTAL CONCERNS:
of 28 June 2004
This case is also known as the White Swan Cleaners Ground Water Contamination
site and the Wall Township Ground Water Contamination site. In 1997, the
Monmouth County Health Department (MCHD) was notified that analytical
testing by a resident had revealed several irrigation wells on Magnolia
Avenue in Wall Township were contaminated with tetrachloroethylene (also
known as perchloroethylene, or PCE). PCE is a volatile organic chemical
that is commonly used as a dry cleaning solvent and degreasing agent.
MCHD subsequently performed testing that confirmed irrigation wells in
the Magnolia Avenue area were highly contaminated with PCE, as well as
with lower levels of trichloroethylene (TCE). In 1999, MCHD and NJDEP’s
Remedial Response Element conducted a joint study to delineate the PCE
contamination in the ground water and evaluate the risk to Sea Girt’s
municipal supply wells. The ground water study included sampling additional
private irrigation wells, testing the surface water at Wreck Pond in Sea
Girt Borough and Spring Lake Heights and monthly sampling of Sea Girt’s
municipal supply wells. The study revealed that a plume of shallow ground
water contamination extended eastward from Route 35 in Wall Township into
Sea Girt Borough and a small part of northern Manasquan Borough, and that
low levels of PCE were present in the surface water in a portion of Wreck
Pond. The federal Agency for Toxic Substances and Disease Registry (ATSDR)
reviewed the sampling results and concluded that the ground water was
safe to use for irrigation. MCHD and NJDEP also determined that the water
from Sea Girt’s municipal supply wells met New Jersey Drinking Water Standards.
However, as a precautionary measure, Sea Girt Borough installed a treatment
system at its well field to remove potential volatile organic contamination.
There are no private potable wells at risk of being contaminated due to
the ground water plume.
In 2001, NJDEP completed an investigation that identified two defunct
dry cleaning establishments and an active gas station in Wall Township
as likely sources of the ground water contamination. Extensive soil and
ground water contamination was subsequently confirmed at one of the locations,
the former White Swan Dry Cleaners on Sea Girt Avenue (now a bank). Based
on these findings, in late 2001 NJDEP decided to test the indoor air at
residences and a commercial business near the bank for PCE vapors. The
testing showed that the indoor air in several adjacent buildings had significantly
elevated levels of PCE vapors and the indoor air at some of the more distant
properties exhibited low levels of PCE vapors. NJDEP and USEPA installed
ventilation systems at several buildings close to the bank to reduce the
PCE vapors to acceptable levels. The bank excavated 820 cubic yards of
contaminated soil from its property in December 2001 and backfilled the
excavation with clean soil under the oversight of NJDEP’s Responsible
Party Remediation Element. The Potentially Responsible Parties for the
two other suspected sources of the ground water contamination, the former
Sun Cleaners and a service station on Route 35, have not conducted any
investigative or cleanup work at their properties.
In early 2002, USEPA began addressing the Magnolia Avenue Ground Water
Contamination site under its Removal Program. Under this program, USEPA
is conducting additional indoor air testing at residential and commercial
properties, installing subsurface vapor mitigation (ventilation) systems
at properties with high levels of PCE vapors and investigating the two
other possible sources of the PCE contamination. NJDEP is installing subsurface
vapor mitigation systems in buildings where low levels of PCE vapors have
been confirmed. As of December 2002, USEPA had tested the indoor air at
more than 250 properties in Wall Township, Sea Girt Borough and Manasquan
Borough and installed subsurface vapor mitigation systems at nine properties.
NJDEP has installed subsurface vapor mitigation systems at 18 residences.
Monitoring and maintenance of those systems is underway. NJDEP plans to
conduct an investigation to delineate the shallow ground water contamination
in 2003. This information will be used to plan future indoor air testing.
USEPA has proposed adding this site to the National Priorities List of
Superfund sites (NPL).