The Delaware Department of Natural Resources and Environmental Control’s (DNREC’s) Division of Air and Waste Management Site Investigation and Restoration Branch (SIRB) will hold a public hearing on its proposed plan of action regarding the Burton Island Old Ash Landfill Site on Thursday, May 29, at the Town of Millsboro Civic Center, 322 Wilson Highway in Millsboro.
According to Gregory M. DeCowsky, project manager and environmental scientist with SIRB, the area was used by Delmarva Power and Light (DP&L) for coal ash disposal during the years 1957-1979, before regulatory requirements, or even DNREC, existed. It has also reportedly been used for disposal of dredge spoils.
“After new solid waste disposal regulations at the end of ’70s into the early ’80s, they discontinued it use,” DeCowsky explained. “It sat there, occasionally getting dredged out, until the summer of 2005, when one of DNREC’s Solid Waste people was out there and saw the edge, where it had eroded, and referred it to us.”
After DNREC obtained sediment and soil samples at the site, they were found to be contaminated with metals above risk standards. DNREC then notified the current owner, Indian River Power LLC, an affiliate of NRG Energy, of their concerns about the site. They entered into a voluntary cleanup agreement with SIRB, to address the contamination. DeCowsky said cleanup work is already in progress.
The site encompasses a 144.23-acre portion of a parcel on the premises of the Indian River Generating Station (IRGS) and consists of three areas DNREC-named Operable Units (OUs). OU1 is the shoreline; OU2 is the landfill/disposal area itself, and OU3 is offshore — the sub-tidal sediments and the waters outside of the footprint of the erosion control project.
The proposed plan to be discussed at the May 29 hearing pertains to OU1 and OU3 only. According to DeCowsky, there will be further investigation into OU2 later this year.
DNREC states that “soils, sediments, shallow groundwater and surface water are contaminated by metals commonly associated with coal ash from electric generating plants. The constituents of potential concern included arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, vanadium and zinc.”
“We divided the site into OUs to allow us to address the most urgent problem of erosion of contaminants into the water first and to follow through with it,” explained DeCowsky.
After SIRB received an evaluation performed by Shaw Environmental in 2007, they reviewed it and made comments. The facility evaluation, or FE, which was done on behalf of NRG and IRPLLC, included a human health risk assessment and a screening-level ecological risk assessment.
Regarding shoreline sediments, “Subject to specific comments and corrections mandated by DNREC, was sufficiently detailed and comprehensive to serve as a remedial investigation.” The report concluded. In other words, according to DeCowsky, they could “move forward with respect to the shoreline areas” in developing a plan for remedying the situation.
“With respect to the offshore sediments, the risk to humans or environmental targets was so low it was below our cutoff,” explained DeCowsky. “Although a slight statistical risk level was reported by Shaw for OU3, the extremely conservative assumptions used in that calculation are what drives that.”
DeCowsky said that someone will be at the hearing to explain the human health risk findings in more detail.
The plan proposes that NRG/IRPLLC install erosion control measures for the shoreline in the form of armor stone “riprap” along with a synthetic fabric along the shorelines, as well as an adoption of an operations and maintenance (O&M) plan.
At a minimum, the plan would include annual monitoring of sediment quality, the armor stone structures, the survival and integrity of the shoreline wetlands; methods of securing the site to prevent public exposure to contamination; performance standards; and requirements for timely corrective measure should “the remedy not perform as designed or is not protective of human health and welfare and the environment.”
It also proposes a uniform environmental covenant restricting future use of OU1. Because the report showed no significant risks were posed by offshore sediments, no further action was proposed for that area (OU3).
“The erosion control is for OU1,” clarified DeCowsky. “But the ‘no further action’ for OU3 is considered a ‘remedy’ under the HSCA legal definition once it is in a final plan.”
“Basically, the erosion into the creek and river is the immediate problem,” he said. “The priority is to stabilize the shoreline so it won’t continue to erode.”
He said remedies for OU2 are not being considered with this plan, as it is a bigger area and needs to be studied further.
The Hazardous Cleanup Act (HSCA) of 1990 ensures that members of the public are informed about environmental problems and are given the chance to express their opinions concerning clean-up before DNREC takes action.
The proposed plan for remediation, which can be found it is entirety online at http://www.dnrec.state.de.us/dnrec2000/divisions/awm/sirb/announce.asp and includes a map and images, has detailed information relayed in a way designed for the general public to comprehend.
For more comprehensive reports or any of the documents created during the course of the investigation, visit the Web site at www.dnrec.state.de.us/dnrec2000/Divisions/AWM/sirb/sitefiles.asp, where SIRB has filed scans of more than 1 million pages of contaminated site file pages. For more information on the voluntary clean-up program, visit http://www.dnrec.state.de.us/dnrec2000/Divisions/AWM/sirb/vcp.asp.
Citizens will be able to ask questions at the May 29 hearing. The public comment period ends at 4:30 p.m. on June 3. People can send their written comments to the DNREC office or call project manager Gregory DeCowsky at (302) 395-2600.