The U.S. Army Corps of Engineers (USACE) is issuing this notice to present their plans for completing remediation of the former New Cumberland Army Depot landfill located at Marsh Run Park. Pursuant to the Record of Decision (ROD) issued by the Pennsylvania Department of Environmental Protection (PADEP) in 1991, the USACE designed and installed a groundwater pump and treat system and a soil vacuum extraction system to remediate the site. In late 1996, the groundwater pump and treat system was removed from service due to a fire. In 1999, the remedy was modified by the first Explanation of Significant Differences (ESD) to utilize monitored natural attenuation and enhanced soil vapor extraction. The enhanced soil vapor extraction system operated for approximately 2.5 years and removed an estimated 225 pounds of contamination before it was shut down because it had reached its limit of effectiveness.
Now that the treatment activities have ended, the USACE plans to utilize natural attenuation and land use controls to continue to prevent exposures to the onsite landfill material, subsurface soil, and groundwater, and to restrict the potential offsite use of groundwater where it may contain concentrations above drinking water standards. The table below illustrates the significant differences between the original remedy presented in the ROD, and the subsequent modifications:
|
ITEM
|
ORIGINAL REMEDY (1991 ROD)
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FIRST MODIFICATION (1999 ESD)
|
SECOND MODIFICATION (2012 ESD)
|
|
Treatment Streams
|
Soil Vapor, Groundwater
|
Soil Vapor, Groundwater
|
None
(Treatment Completed)
|
|
Soil Vapor Treatment
Method
|
Soil Vapor Extraction
|
Enhanced Soil Vapor
Extraction
|
Completed
|
|
Soil Vapor Treatment
Duration
|
1 year
|
2 years
|
Completed
|
|
Geosynthetic Cap
|
None Present
|
Placed over Source Area
|
No longer needed since Soil Vapor Treatment complete.
|
|
Extracted Groundwater
Treatment Method
|
Air Stripping plus Activated
Carbon
|
Air Stripping plus Activated
Carbon
|
Treatment Completed
|
|
Design Approach: Soil Vapor
|
Source Treatment
(landfill area)
|
Source Treatment
(landfill area)
|
Source Treatment (Completed), Institutional (Land Use) Controls
|
|
Design Approach: Groundwater
|
Containment
|
Monitored Natural Attenuation
|
Monitored Natural Attenuation (modified monitoring and frequency) and Institutional (Land Use) Controls
|
The implementation of additional land use controls, the modified remedy will be protective of both human health and the environment, will meet the Remedial Action Objectives and Federal and State requirements, and is cost-effective. In addition, the site remediation has utilized permanent solutions and alternative treatment technologies to the maximum extent practical.
The administrative record file for the site, which contains the ESD and all documents that formed the basis for the site remediation, are available for public review at the locations listed below. Questions may be directed to Ms. Liza Finley at (410) 962-2683.
New Cumberland Public Library Fairview Township Municipal Building
1 Benjamin Plaza 599 Lewisberry Road
New Cumberland, PA 17070 New Cumberland, PA 17070
www.twp.fairview.pa.us