During initial environmental studies, the Brookhaven National Laboratory
(BNL) site was subdivided geographically into seven Operable Units (OU).
Shortly thereafter, two of them were combined to form OU II/VII. The main
Operable Units dealing with soil contamination are OU I and OU II/VII.
Operable Unit IV also addresses some soil contamination.
Operable Unit I was originally defined as a 950-acre area in the
southeastern part of the BNL site. Later, to facilitate the cleanup process,
similar types of contamination from different Operable Units were grouped
together. Soils contaminated with radioactive materials from areas
originally included in OU II/VII, IV and VI are being cleaned up under OU I
because they have similar contaminants.
Operable Unit II/VII is located in the central, developed portion of
the BNL site. It consists of four "areas of concern" - the Waste
Concentration Facility, aerial radiation survey locations, the former Low
Mass Criticality Facility, and storage yards for the Alternating Gradient
Operable Unit IV is also located in the central, developed portion of
the BNL site. Its area of concern is the Central Steam Facility. OU IV also
addressed the Reclamation Facility and Sump Outfall Area, which has since
been transferred to OU I (see below for more).
Operable Unit I
The principal soil contaminants in Operable Unit I are radioactive elements,
primarily cesium-137 and strontium-90. Elevated levels of heavy metals are
also found in some locations. All soil contaminants are confined to BNL
property, and access to these areas is controlled as needed to protect
employees and the public.
Radiologically contaminated soils
Former Hazardous Waste Management Facility (FHWMF) - The largest
volume of contaminated soil was located at the HWMF. It was used from 1947
to 1997 as a central receiving, processing and storage facility for
radioactive and hazardous waste generated at BNL. The primary soil
contaminants at the FHWMF were cesium-137 and strontium-90. Elevated levels
of heavy metals (mercury and lead) were also present in isolated areas.
Cleanup at the FHWMF began during the summer of 2003 with the controlled
demolition of several building structures. Workers tookdown buildings
piece-by-piece to minimize dust production and other unnecessary exposure.
After the buildings and (if necessary) foundations were removed,
approximately 15,000 cubic yards of contaminated soil were excavated from
about 13 acres of land. The work was completed in 2005.
Reclamation Facility and Sump Outfall Area - Radioactive elements
were found in soils at the reclamation facility and in a sump outfall east
of the facility. This facility was used from the late 1950s through the late
1960s to clean radioactive contaminants from clothing and equipment. It is
no longer used for decontamination, although it is still in use for routine
laundry. Water from decontamination of equipment was discharged at the sump
outfall area until late 1969. Soils at the sump outfall contain elevated
levels of cesium-137 and strontium-90, as well as minor concentrations of
other radioactive elements. The contaminated soil was excavated and shipped
off site for disposal in 2002.
Upland Recharge/Meadow Marsh Area - This area was used in sewage
treatment experiments from 1973 to 1978. Sediments in two of the manmade
basins contain elevated levels of heavy metals such as copper, zinc and
aluminum. The Meadow Marsh ponds were cleaned up in the summer of 2003 and
now function as a habitat for the Tiger Salamander population.
Storm Recharge Basins - These two basins are used to recharge runoff
that enters BNL's storm sewer system. Their sediments contain elevated
levels of heavy metals such as copper and lead, as well as organic
Wooded Wetland - This area is located adjacent to the current
landfill and received runoff from that landfill. Sediments here contain
elevated levels of metals such as aluminum.
Two Upland Recharge/Meadow Marsh basins were excavated and reconstructed
as part of BNL's cleanup program. The storm recharge basins continue to
operate and will be monitored. A Tiger Salamander Habitat Management Plan
details the routine maintenance required at these basins. BNL conducts annual monitoring of surface water and sediments at the Wooded
Both heavy metals and radioactive elements were found in an ash pit, used
from 1943 to 1963 to dispose of incinerator ash. Levels of contaminants were
typical of those found in incinerator ash. Radioactive elements found here
were common in incinerator ash and were unrelated to research operations at
BNL. This area was cleaned up in the summer of 2003. The ash pit cleanup
involved removing some trees, backfilling soil to even out the grade,
placing 12 inches of topsoil to cover the ash, and reseeding the area with
A removal action is an accelerated cleanup response to a known contamination
source. The following areas of concern in Operable Unit I have
been addressed as removal actions:
Former and Interim Landfills - These closed landfills, including a
slit trench, were a source of groundwater contamination from volatile
organic compounds (VOCs) and strontium-90. The landfills, which cover nine
acres of land, were used from 1947 to 1966 for the disposal of general
waste, construction debris and chemicals. These landfills have been capped.
Annual reports for the landfills can be found here.
Current Landfill - This closed eight-acre landfill was a source of
VOC and tritium groundwater contamination. It was used from 1967 to 1990 for
the disposal of the same materials as the other two landfills. The current
landfill is no longer in operation for waste disposal and has been capped.
Annual reports for the landfill can be found here.
Chemical Holes - These 55 waste pits were a source of VOC and
strontium-90 groundwater contamination. They were used from the late 1950s
to 1981 for the disposal of biological waste, chemical containers and
glassware. These holes were excavated in 1997. Soil and debris were packaged and shipped off site for disposal
Groundwater - VOCs from the current landfill and the HWMF have
migrated into the groundwater. Rainwater percolating through contaminated
soil can pick up the VOCs and transport them into the groundwater. An air
stripping system began operating in December 1996 to treat this groundwater.
It has treated over 2.8 billion gallons of groundwater, and has removed over
300 pounds of VOCs.
Operable Unit II/VII
Waste Concentration Facility
Cesium-137 and strontium-90 contamination was found in soils here. This
facility has been used since 1949 for reducing the volume of liquid
radioactive waste prior to disposal. It is still an operational facility.
Three large storage tanks were in use here from 1949 to 1987, and were
removed in 1994. Six underground tanks and
piping, along with radiologically contaminated soils, were removed as
part of BNL's environmental cleanup in 2005.
Lawns and Landscaping Soils
Low levels of cesium-137 were found in soils near several buildings in the
center of the BNL site. Soils from the HWMF were used as landscaping and
fill material at these locations. These soils were excavated in 2000 and the
soil sent for off-site disposal. The excavated areas were backfilled with
clean soil and were reseeded.
Two other areas at BNL were examined for radiological contamination. The
Alternating Gradient Synchrotron (AGS) storage yards hold steel and
equipment that is being stored for potential reuse at the AGS. The former
Low Mass Criticality Facility was used for research from the mid-1950s to
the mid-1960s, and for temporary drum storage from June 1983 to March 1984.
No contamination at levels of human health concern was found at these two
locations. No cleanup of these areas is required. Institutional controls and
monitoring will continue.
Operable Unit IV
Central Steam Facility
This facility supplies heating and cooling to all major BNL buildings and
includes aboveground fuel tanks connected to a boiler building (Building
610) by aboveground and underground pipes. In the past, the Central Steam
Facility included underground fuel storage tanks.
In November 1977, a spill of about 25,000 gallons of a waste oil/solvent
mixture occurred. The spill pooled on about 1.2 acres and was contained with
sand berms. At that time, portable pumps were used to clean up as much as
possible. They recovered an unknown quantity of the oil and solvent.
A 5,000-gallon underground storage tank, associated piping and visibly
contaminated soil were removed from this area in October 1993. To address
the volatile and semi-volatile contaminants remaining in soils and
groundwater, an air sparging/soil vapor extraction system was installed. It
became operational in November 1997. This system strips volatile and some
semi-volatile contaminants from soils and groundwater into their vapor
phase. The vapors are then extracted from the ground and filtered to remove
the contaminants. To date, this system has removed approximately 35 pounds
of chemicals from the spill area. Monitoring showed that, as of late 2000,
levels of VOCs in area groundwater were below the drinking water standard.
As a result, the system was shut down in January 2001 and dismantled in 2003. Groundwater
monitoring will continue. The five-year
review of the Operable Unit IV treatment system is available.
Operable Unit V
Operable Unit V is an area in the eastern-central portion of BNL. This
area includes the Lab's sewage treatment plant, an active facility used to
process sewage from the Lab's facilities. OU V also includes areas of the
Peconic River impacted by past Laboratory operations, as well as sewer pipes
and groundwater beneath the eastern portion of the Lab and offsite.
The Peconic River receives discharges from the Lab's sewage treatment plant.
During the remedial investigation, elevated levels of heavy metals (such as
mercury, copper, and silver), organic chemicals (such as polychlorinated
biphenyls, or PCBs), and low levels of pesticides (such as DDD, a product of
DDT degradation) and radionuclides were detected in Peconic River sediment.
A cleanup of the river was initiated in May 2004 and completed in May of
2005. Approximately 14,025 linear feet (2.66 miles) of the Peconic River
were remediated between the BNL Sewage Treatment Plant (STP) and just
downstream of Manor Road in Manorville, NY encompassing a riverbed area of
approximately 19.8 acres.
During January 2011 the Peconic River
Sediment Trap, located adjacent to Z path and upstream of stream
gauging station HQ, was removed as required by the Peconic River
ROD. Between November 2010 and January 2011 supplemental
sediment was also removed from the PR-WC-06, Sediment Trap, and
Annual monitoring reports can be found
Sewage Treatment Plant and Sewer Pipes
The Laboratory's sewage treatment plant (STP) processes up to 1.25 million
gallons of wastewater per day. Treated effluent is discharged into the
Peconic River, north of the treatment facility. The main areas of concern
within the STP were the sand filter beds and berms. There are eight sand
filter beds, each covering about one acre and containing three feet of sand
on top of gravel and tile collection pipes. Wastewater is sent through the
sand beds for filtering prior to release.
Some sanitary sewer lines at the Lab were installed as early as 1917, when
the property was in use by the U.S. Army for Camp Upton. These old lines
were repaired and upgraded by the Army in 1942. The Army constructed them
from various materials, including vitrified clay, cast iron and reinforced
In 1987, BNL investigated these lines and discovered that they were leaking.
The Laboratory replaced the sewer pipes leading to the sewage treatment
plant with a new line in January 1993. The old pipes were capped and left in
The remedial actions for these areas included the excavation and disposal of
radiological and mercury-contaminated soils to meet prescribed cleanup
goals, and the removal and disposal of radiological contaminated sludge from
the ten manholes along the retired sewer lines.
Low levels of volatile organic compounds (VOCs), primarily trichloroethene,
were detected in the groundwater of OU V. These VOCs are found at the site
boundary east of the Lab's sewage treatment plant and beyond the Lab's
eastern boundary. The highest total VOC concentrations currently observed in
the plume are less than 20 parts per billion (ppb).
The elevated levels of VOCs originated from discontinued past disposal
practices that resulted in releases of VOCs to the Lab's sewage treatment
plant. Investigations of soil and groundwater at the sewage treatment plant
indicate that there are no continuing sources of VOC contamination.
The elevated levels of VOCs in groundwater off Laboratory property are found
at depths (200 feet) below the depths of most residential wells. Homes and
businesses in the OU V area were offered public water hookups in 1997 to
protect against possible exposure to groundwater contaminants.
No action is proposed for OU V groundwater.VOC concentrations in groundwater
are decreasing. Outpost monitoring wells have been placed along the
predicted path of the groundwater and additional groundwater monitoring data
will be collected. If future monitoring data suggest a need for a
groundwater remedy, the OU V remedy will be modified.
Last Modified: August 24, 2012
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