1.1.1 Incident Category

Soil contamination associated with metal recycling

1.1.2 Site Description

The Site is a former paper and metal recycling business located on Basin Street in Princeton, New Jersey. The recycling business began operations in 1955 and ceased operations in 2003. Allegedly operations at the facility included draining PCB transformers and the burning of wire casings. In 2014 and 2015 NJDEP performed extensive sampling of the surface and subsurface soil on the Site and determined the extent of PCB, lead, SVOC and dioxin contamination. Levels of all of these contaminants exceed the RMLs in Site soils. PCB concentrations (mainly Aroclor 1260) were found as high as 2,800 parts per million (ppm) in surface soils. Lead concentrations were detected as high as 11,300 ppm. Benzo(a)pyrene and dioxin were detected as high as 17 ppm and 1.3 parts per billion (ppb), respectively.

The Site is located in a residential neighborhood and is directly adjacent to a tributary to the Stoney Creek. The Site property is unsecured and accessible to trespassers. The results from the NJDEP sampling indicate there has been a release of CERCLA designated hazardous substances at the Site, which is a facility under Section 101(9) of CERCLA. Based on the available information, a CERCLA removal action is warranted at the Site. An Action memorandum signed by the Region 2 ERRD Director on August 10, 2015 authorized funding for the excavation and off-site disposal of approximately 7,500 tons of contaminated soil.

1.1.2.1 Location

The Site is located at 409 Basin Street in Princeton, New Jersey (Block 11503, Lots 2 & 8). Lot 2 is 0.27 acres in size and contains a dwelling and lot 8 is 0.37 acres in size and is undeveloped. The Site also includes adjacent parcels that have been impacted by the spread of contamination including 403 Basin Street (Block 11503, Lot 1), 413 Basin Street (Block 11503, Lot 3), 417 Basin Street (Block 11503, Lot 7) and multiple Lots in Block 11301. The Site is in a residential neighborhood bordered by lands owned by Princeton University. Residences are located immediately to the south along Basin Street. A Princeton University apartment complex is located within 200 feet to the west of the Site. A tributary to Stoney Creek flows from west to east along the north boundary of the Site.

The Site is located at 40° 19’ 59.44” (latitude) / -74° 39’ 19.6” (longitude).

1.1.2.2 Description of Threat

Analytical data generated from NJDEP soil sampling events in 2014 and 2015 found the above hazardous substances at concentrations well above the EPA RMLs. Elevated concentrations of these contaminants were found in surface soils (0-6 inches BGS) and down to five feet BGS. It is estimated that approximately 7,500 tons of soil will need to be removed from the Site to address the release of hazardous substances.

It is believed that the mechanism for past releases on the Site include improper management of transformer waste oils (PCBs), burning of wire and debris (dioxin and benzo(a)pyrene) and uncontrolled storage of metallic wastes (lead). The threat of future releases from the Site exists through the spread of soil contamination through surface water run-off, windblown dust and/or human tracking.

 
1.1.3 Preliminary Removal Assessment/Removal Site Inspection Results

Beginning in 2014, NJDEP performed extensive soil sampling at the Site to delineate the extent of contamination. As of June 2015, NJDEP had performed four iterative rounds of soil sampling at the Site. Surface soil (0 – 6”) was sampled within the main Site property in May 2014.  Forty-six samples were collected. With the exception of two samples, all results showed elevated levels of PCBs, lead and/or benzo(a)pyrene above NJDEP’s residential standards.

A second round of delineation samples were collected by NJDEP in August 2014. The original 46 sample locations were expanded to eighty-three locations; both deep samples within the Site where contamination had been detected and surface samples along the outer perimeter of the Site. The results indicated deeper contamination (18’’– 24”) in some areas. There was additional horizontal contamination above acceptable levels to the north, west and east of the main Site property. In addition to the PCB, metals, and SVOCs analyses, the second round included dioxin samples from where an open burn pit was thought to have been located. Dioxin results were as high as 1.3 ppb in this area.

In December 2014 and June 2015, a third and fourth round of samples were collected to complete the delineation of the horizontal extent of the surface contamination and to delineate the extent of  vertical contamination in the sample points that had not reached an uncontaminated zone.  Additional dioxin samples were also secured.

Overall the sample results indicate that the soil throughout the Site is contaminated with PCBs, lead, and benzo(a)pyrene above both  NJDEP residential and non-residential standards and EPA RMLs. Dioxin is found above the NJDEP Action Level in several “burn pit’ locations on the Site.

Excavation operations continue. Approximately 2,500 cubic yards of contaminated soil have been excavated to date and have been staged on-site until analytical results were received and waste profiling could be completed.  A site excavation and material segregation plan based on PCB and lead content has been developed using existing site data and is being used to excavate and segragate the soil into waste streams. Soils anticipated to be higher in contamination are being segregated and staged separately from anticipated lower-level soils in order to minimize disposal costs. Once stockpiled, excavated soils are being sampled to confirm accurate waste profiling. The majority of the soil analyzed to date for disposal (about 1500 tons) has been determined to contain PCBs in excess of 50 ppm and will be disposed of as Toxic Substances Control Act (TSCA) regulated material.  Contaminated soil load-out is tentatively scheduled to begin by 11/6/15.  Staged soils are being covered daily at the end of each shift to eliminate the possibility of off-site migration via wind and/or rain.  TSCA soil will be transported by truck to a U.S. Ecology transfer facility in North Bergen, New Jersey.  There the soil will be loaded onto rail cars and tansported to Wayne Disposal In Michigan for landfilling.

Excavation operations have been focused in the western portion of the site where the deepest cuts are required. The entire 8 foot excavation area has been completed and backfilled.  The entire 7 foot excavation area has been excavated and approximately half has been backfilled with clean fill.  Top soil will be brought in at a later date to complete final grades/restoration.  NJDEP Certified Clean Backfill is being brought in from the Trap Rock Industries Moores Station Quarry in Hopewell Township, New Jersey.  Topsoil sources are being evalauted for clean fill certification.

Bedrock was encountered between 6.5 and 7 feet BGS in the deepest (8 feet) part of the planned excavation.   An old 24" concrete sanitary sewer pipe now being used for communication conduits was also discovered in the excavation in the western (Lawrence Drive) portion of the site at approximately 5 feet BGS.  This pipe is owned by Princeton University and they have requested that it not be disturbed. This area also has a bedrock high at a similar elevation in an 8'x8' area immediately west  of the pipe. The pipe and the bedrock high are sitting in the area prescribed for an 8 foot depth excavation. EPA is limiting the excavation in this approximately 8'x40' area to six feet in depth to protect from undermining or damaging the pipe and because digging into bedrock is not possible.  NJDEP has agreed with this change in the excavation plan and has asked for one post excavation sample near the pipe in this area.  This sample was collected on October 26, 2015.  NJDEP also agreed that the encountering of bedrock in the excavation would represent the bottom of the dig regardless of the planned and agreed upon depth of excavation. 

In the planned 7 foot part of the excavation bedrock was encountered as shallow as 5.5 feet BGS.  Excavation attempts were ended in this area at between 5.5 BGS and 7 BGS depending on depth to bedrock.  In this 7 foot planned excavation area strong PCB odors were encountered at the bedrock surface and in the berock surface fractures.  This indicates PCBs have migrated down through the soils and into the bedrock on the site.

Tree removal operations were initiated on 9/2/15.  Approxmiately 56 trees have been cut down and removed from the excavation area to date. The trees have been processed in a chipper and the wood chips have been used as cover within the operational area to aid in dust suppression.  EPA is maintaining an inventory of tree type, size and condition for all trees being removed.  The inventory will be used to develop a plan for site restoration.

EPA continues its efforts to preserve trees in the shallow excavations and is evaluating excavation techniques that might minimize the need for tree removal.  A certified tree expert was retained and visited the Site on 11/2/15 to provide guidance on large native tree specimens that have been marked for preservation by the property owners.  The tree expert has indicated that most of these trees may not be salvageable based on the extent of the required excavation; a report on his findings and recommendations is pending.

The EPA RST contractor completed soil and sediment sample collection in the floodplain of Alexander Creek and in depositional areas along the stream down to the confluence with the Stoney Creek. Analytical results will be used to determine whether Site contamination has impacted the floodplain via rainwater run-off.  Analytical results are expected in approximately 30 days.

A Community Air Monitoring Plan (CAMP) has been developed for this site.  Continuous real-time air monitoring for total dust particulates is being conducted on a daily basis as per the Plan.  A site action level of 150 micrograms per cubic meter (ug/m³) has been established as an 8 hour time-weighted average.  No exceedances have been experienced to date.  Additionally, periodic air sampling is being performed in conjunction with the continuous air monitoring.  Air samples have been collected for PCB, lead and benzo(a)pyrene analyses to confirm real-time air monitoring results.  Air sampling results indicate that all contaminants remain below method detection levels for all samples collected to date. 

2.1.2 Response Actions to Date

The following response actions have been implemented to date: 

·     Developed a site health and safety plan, quality assurance project plan, and community air monitoring plan.

·     Mobilized an Emergency and Rapid Response Services (ERRS) contractor to establish support zones, contaminant reduction zones, and exclusion zones. Initial work included marking out underground utilities and establishing excavation and staging areas.

·     Established engineering controls to assure proper management of excavated materials (i.e. dust suppression, lined soil staging area, erosion and sedimentation control).

·     Conducting air monitoring in order to monitor proper site management of excavated soil and protection of site workers and community members in close proximity to the site.

·     Excavated and stockpiled approximately 2,500 cubic yards of contaminated soil.

·    Determined acceptable local backfill sources. Backfilling of the excavation has been performed as digging progressed.

2.1.3 Enforcement Activities, Identity of Potentially Responsible Parties (PRPs)

EPA is conducting PRP search activities including interviews and the preparation of 104e and notice of liability letters.

2.1.4 Progress Metrics

2.2.1 Anticipated Activities

• Contaminated soil load-out operations are expected to begin on 11/6/15. 
• Excavation and backfilling activities will continue.
• EPA will develop a tree replanting and site restoration plan based on recommendations from a certified tree expert.
  
  2.2.1.1 Planned Response Activities

• Continue contaminated soil excavation.
• Continue backfilling operations with certified clean fill in completed excavation areas.
• Continue air monitoring and air sampling per the Community Air Monitoring Plan.
• Site restoration including establishing final grades with certified clean top soil, tree planting, grass/sod installation and re-establishing of natural areas.
  
  2.2.1.2 Next Steps

Load-out of contaminated soil is the next critical step to allow room for further excavation.  Excavation and soil stockpiling will continue.

2.2.2 Issues

• Soil excavation was limited in portions of the deepest excavations due to bedrock and encountering an old sanitary sewer pipe that is currently being used as conduit for Princeton University communications cable.  The NJDEP was notified of the impediments to achieving the planned excavation depths and visited the Site on 10/26/15.  A soil sample was collected at their request to the west of the sewer pipe to evaluate contaminant levels of soils left in place to protect the pipe.  Areas where bedrock is preventing excavation cannot and will not be sampled.
• A much greater than anticipated amount of TSCA regulated material has been encountered than was anticipated.  An Action Memorandum to request additional funding will be developed to account for additional costs required to dispose of the increased amount of TSCA regulated material. 

2.5.1 Safety Officer

No safety issues to date.

2.5.2 Liaison Officer

Pat Seppi from EPA PAD has been assiting with community outreach.  Meetings have been held with the Princeton University Community and the Town officials to discuss the site activities including EPA's air monitoring. 

2.5.3 Information Officer

EPA - 2 OSCs - Cris D'Onofrio and Dave Rosoff

ERRS (ER) - 6 employees (RM, FCA, 2 operators and 2 Techs)

RST (Weston) - 2 employees (Air monitoring/sampling, survey and photo documentation)