DuPont is to clean-up an old run-off pond that’s been leaking chemicals into the River Faughan since the late 1970s.
The manufacturer has applied to Derry City and Strabane District Council for permission to carry out decontamination works on the pond that it acquired from the British Oxygen Company (BOC) 37 years ago.
According to a remediation plan prepared by the engineering services firm, CH2M, for DuPont, Ethylene Dichloride, produced by BOC at Maydown in the 1960s and 1970s, has been seeping from the 10,300 square metre pond or ‘warehouse pit’ for years.
The plan points out how the pond became the focus of site investigations “due to elevated Ethylene Dichloride concentrations in groundwater and sporadic Ethylene Dichloride concentrations in the adjacent River Faughan greater than the Environmental Quality Standard (EQS)”.
It adds: “Risk assessment efforts have since confirmed complete environmental pollutant linkages, which represents a constraint to land redevelopment.
“Free-phase Ethylene Dichloride and Ethylene Dichloride-impacted soils were encountered immediately outside the warehouse pit (at shallow depths), which represents a source area that could persist for many decades.
“Ethylene Dichloride concentrations in groundwater, as high as 1,400,000 µg/L, have been measured in shallow groundwater that discharges to the River Faughan resulting in periodic EQS exceedances. “However, the exceedances are sporadic within the tidal river and annual average EDC concentrations do not exceed the EQS (with the EQS being an annual average criteria).”
DuPont propose using Daramend, a vegetable and mineral material based substance to clean up the pond and soil.
In a statement DuPont said it is committed to the highest standards of safety and environmental stewardship at its facilities.
It stated: “In fact, DuPont has been working for several years to develop a plan for remediation of ethylene dichloride in soils and groundwater at the Maydown site.
“Soil and groundwater were contaminated by a previous land owner, and DuPont is addressing this legacy issue in accordance with existing regulations and our commitment to environmental stewardship.
“We have been working cooperatively with several government agencies, including the Derry City Health Department, throughout the process. A risk assessment conducted according to British regulations (CLR11) has determined there is no adverse human health impact to the community. Our remediation plan has been submitted through the Council’s Planning Department for approval by a variety of public agencies including but not limited to: Northern Ireland Environment Agency, Lough’s Agency, Derry City Health Department, Shared Environmental Services. We expect to complete the work under the current application in 2018.”