![Text Box: The Army sent a letter dated July 16, 2008 to George Pavlou, Acting Director of the USEPA Region II Emergency and Remedial Response Division; the letter was a response to the USEPA’s earlier submitted position paper and was sent just prior to the July 24, 2008 meeting between the Army and the USEPA. In the letter, the Army stated that they had “agreed that risk at this site [Mid-Valley] does warrant remedial action for the groundwater and has agreed to restore the groundwater to meet drinking water standards.” In the position paper, the Army stated that their “reviewers were disappointed by the apparent lack of acknowledgement of the Army’s agreement to restore groundwater to MCLs” – both at the February 19, 2008 informal dispute resolution meeting and in the April 14, 2008 Army response to USEPA comments. The Army stated that they indicated that “the FS will be revised to include the MCL [Maximum](image095.gif)
|
Contaminant Level] as an ARAR for the proposed groundwater remedial action.” In the letter the Army further states that their position is that “the trigger for remedial action under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”) is a determination of unacceptable risk based on a baseline risk assessment that considers reasonable maximum exposure.” The Army notes that “if the baseline risk assessment concludes that the risk is unacceptable – based on the current and reasonably foreseeable uses – a response action is required. During that step, the lead agency develops a response action that identifies and complies with all ARARs, including MCLs for groundwater.” The Army also questions EPA’s determination of reasonable maximum exposure scenario and reiterates that EPA defines ‘reasonable maximum’ to include ‘only potential exposures that are likely to occur.’ The Army cites |
|
various guidance including the EPA Risk Assessment Guidance for Superfund (RAGS) in which the Army notes that according to RAGS: “Because residential land use is most often associated with the greatest exposures, it is generally the most conservative choice to make when deciding what type of alternate land use may occur in the future. However, an assumption of future residential land use may not be justifiable if the probability that the site will support residential use in the future is exceedingly small.” The Army states that they have accepted the EPA’s “programmatic expectation to return groundwater to beneficial use and strives to achieve that expectation within a reasonable timeframe considering site specific factors” but that the USEPA has failed to recognize that. Finally on the issue of a surface water ARAR the Army states that “any incremental risk |
|
associated with surface water exposure is insignificant based on the concentrations in the surface water. The only possible way surface water exposure would result in elevated risk would be to assume use of the surface water body as a drinking water supply at the location where groundwater daylights into surface water.” The Army notes that such a scenario is unreasonable. Using a youth visitor as a current and likely future receptor for surface water exposure the Army calculated the cancer risk to be 1.4 x10-9 to 1.2 x 10-7 (compare to 10-4 to 10-7) with a hazard index range of 0.002 to 0.01 (compare to 1.0). The Army concludes that the “groundwater remedy will reduce concentrations discharging to Robinson Run to levels below the New Jersey Surface Water Criteria (‘NJSWC’). However, because there is no unacceptable risk associated with surface water
the NJSWC cannot be an ARAR.” |
|
PUBLIC HEARING FOR PROPOSED PLAN |
|
A public hearing for Site 61/104 (PICA 102) was held on April 17, 2008 at the Hilton Garden Inn in Rockaway, New Jersey. Representatives of the Army coordinated the presentation which was given by Arcadis. Bill Roach of the USEPA and Jim Kealy |
|
of the NJDEP were in attendance. Mr. Roach noted that the Proposed Plan for Site 61/104 had been approved for release for public comment but had not yet been formally approved by the USEPA. Mr. Kealy commented that the |
|
NJDEP had reviewed the plan and was in favor of it. The proposed plan addressed soil, sediment, and surface water at the subject site; groundwater in the area is being handled as part of the Mid-Valley study area. |
|
The Army’s preferred alternatives are has follows: soil – alternative S-5A: excavation and off-site disposal of selected impacted soils from Site 104 and LUCs (land use controls) with maintenance of |
