Progress

Background

While surface oil spills can often be cleaned up quickly and efficiently using absorbent materials and vacuums, underground accumulations of petroleum product – such as the one in Greenpoint – are typically more difficult to reach and take much longer to recover.

ExxonMobil’s goal is to remediate the petroleum contamination stemming from our historical operations in Greenpoint as quickly and safely as possible. This includes recovery of product, treatment of water, and monitoring and addressing soil vapors.

Recovery & treatment progress

Dual-pump recovery

According to the 2007 U.S. Environmental Protection Agency Report, the dual-pump recovery is the most efficient and best sub-surface option for remediating the petroleum contamination underneath a section of Greenpoint. The system recovers product by depressing the water table around the recovery well to create a cone of depression which allows the petroleum products to flow into the recovery well. One pump in the recovery well removes the water, and the other pump removes petroleum products into storage tanks.

Recovery & treatment progress

Groundwater treatment

Groundwater removed by the dual-pump system is treated to remove contaminants, and tested to ensure its compliance with state and local regulations before being released into Newtown Creek.

Water entering the system is held in a stabilization tank to allow it to settle.
Air is injected into the water and passes it through filters that remove iron and magnesium.
Petroleum components are removed from the groundwater by a process called air stripping. ExxonMobil’s process injects air through the water as it cascades down through a series of trays with holes of decreasing size that strip the contaminants from the water.

Recovery & treatment progress

Groundwater treatment

Treated water is piped to one of two discharge points into Newtown Creek.
During typical operation the recovery system pumps and treats up to 15 million gallons of groundwater each month.
The discharged groundwater is sampled monthly and results are reported to the New York State Department of Environmental Conservation.

Vapor testing

Vapor results

ExxonMobil regularly samples and evaluates subsurface soil vapors in Greenpoint in accordance with New York State Department of Health (NYSDOH) guidance. Air vapor tests were conducted on 52 homes from January to March 2007. No evidence was found of petroleum vapor intrusion from the underground contamination in residential homes.

Vapor testing

Soil vapor results:

Residential areas:

ExxonMobil’s investigations in residential areas show no unusual soil vapor concentrations above the contaminated area and are similar to background concentration results. These concentrations are also consistent with readings outside the contaminated area, according to a study conducted by the NYSDOH.
Based on our findings, the contaminated area is not impacting shallow soil vapor beneath the residential area, and shallow soil vapor does not pose a health concern in this area. Scheduled and thorough soil vapor monitoring helps ensure public health.

Vapor testing

Soil vapor results:

Industrial/commercial areas:

In 2005, during ExxonMobil’s bi-annual soil vapor testing of all property near the area of petroleum contamination in Greenpoint, elevated soil vapor concentrations were found in the shallow subsurface in isolated sections of the industrial/commercial area of Greenpoint.
ExxonMobil took immediate action and did two things: conducted indoor air testing and began a thorough investigation to determine the source of the soil vapors. ExxonMobil continues to sample soil vapor twice each year and report the results to the New York State Department of Environmental Conservation (NYSDEC).

Vapor testing

Soil vapor results:

Industrial/commercial areas:

Indoor air testing: ExxonMobil conducted indoor air testing within offices located in the industrial/commercial area and the investigation indicated there were no indoor air quality impacts associated with vapor intrusion. These findings were submitted and approved by the NYSDEC.
Soil vapors: When ExxonMobil discovered the soil vapor data, it began a thorough investigation process to determine the source of the elevated soil vapor concentration levels and the precise location of the impacted area. Through the research, ExxonMobil was able to determine the perimeter of the affected area and determine the appropriate remediation strategy. The state has approved the soil vapor remediation plan, which includes creation of a soil vapor treatment facility, and outlines a remediation schedule.

Vapor testing

Air vapor results:

In 2007, NYSDEC and NYSDOH conducted an air vapor intrusion investigation in the residential area. Samples taken underneath foundation slabs were compared with basement and first floor samples, as well as outdoor samples, with consistent results: no petroleum air vapors have been linked to the underground petroleum contamination based upon the state’s research.

Vapor testing

Air vapor results:

ExxonMobil also monitors ongoing and planned construction in both the residential neighborhood and commercial/industrial zones above the underground contamination. We contact parties responsible for construction to ensure that appropriate procedures for digging or excavating are followed.

Product recovery - 1979 to present

ExxonMobil & Greenpoint

ExxonMobil takes its environmental remediation responsibilities seriously. Our goal is the same as the community's – to remediate the petroleum contamination stemming from our historical operations in Greenpoint as quickly and safely as possible.
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Community programs

As an active and longstanding member of the Greenpoint community, ExxonMobil works with neighborhood groups and participates in local events and initiatives.
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Community news

ExxonMobil’s newsletters include updates on remediation efforts and features people and events from the community of Greenpoint.
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ExxonMobil has deployed substantial resources and is making significant progress in cleaning up the petroleum contamination under a portion of Greenpoint.

Background

Vapor results

Product recovery - 1979 to present

ExxonMobil & Greenpoint

Community programs

Community news