Contact: Michael Globetti, DNREC Public Affairs, 302-739-9902.
Army Creek Marsh remediation project concludes with
once-contaminated site now seen as haven for wildlife
NEW CASTLE (Nov. 1, 2012) – DNREC’s Site Investigation and Restoration Section has given a certificate of completion of remedy (COCR) to Army Creek Marsh that concludes one of the largest ecological remediation project in Delaware’s history – returning 50 acres of the lower marsh to environmental viability after many years as a contaminated industrial site. The Army Creek Marsh site, which includes another 68 acres remediated earlier under the auspices of DNREC, has become a thriving area for wildlife.
The Army Creek Marsh site, formerly occupied by the Amoco Polymer Company, was divided into two operable units (OU-1 and OU-2) by DNREC for the purpose of performing a remedy on the property. The 68-acre parcel known as OU-1 received a COCR in 2003.
BP Amoco entered into DNREC’s Voluntary Cleanup Program (VCP) in 1998 for remediating Army Marsh Creek under provisions of the Delaware Hazardous Substance Cleanup Act (HSCA) 7 Del. C Chapter 91. Through the VCP agreement, BP Amoco agreed to investigate the potential risk posed to public health, welfare and the environment at the site.
The same year, DNREC began evaluating marsh conditions through collection and analysis of sediment samples through Lower Army Creek Marsh. Two types of process residuals, plastic waste and plastic paste were found at the former Amoco Polymer plant located at 950 River Road in New Castle.
The Army Creek Marsh human health and ecological risk assessments were conducted, consistent with DNREC guidance, to evaluate the magnitude of potential health risks to certain segments of the human population and to the environment under post-removal conditions in the marsh’s soils, sediment, and surface water.
Plastic waste onsite consisted primarily of multicolored plastic pellets with some shredded/powdery plastic material throughout. The “paste waste” is grayish, viscous material believed to contain catalyst sludge and includes both metals and alkyl/nonyl-phenols. Upon review of OU-2 (which consists of approximately 50 acres) DNREC established cleanup goals for five metals and alkyl/nonyl phenols.
Additional objectives included:
Removal of paste-type process residuals from the marsh were present
Removal of process residuals from the marsh where sample results exceeded two-times the cleanup goals established by DNREC
Removal of accumulations of the residual plastics (pellets and powder) from the marsh that was greater than one-foot in thickness
Based on its review, DNREC certifies that a remedy consistent with HSCA regulations has been completed at the OU- 2 parcel of the Army Creek Marsh, marking the entire 118-acre site as now environmentally viable and a boon for wildlife in the area.
Vol. 42, No. 432