AREA C ROD NEARING COMPLETION

On May 12, 2009 Picatinny responded to both the USEPA’s and the NJDEP’s comments on the Record of Decision (ROD) for Area C. USEPA had a number of comments, some of them relating to fundamental issues concerning the ROD, whereas the NJDEP had only three comments. The overriding issue raised by the USEPA is that concerning the use of groundwater as a potable water source. Two comments cited below pertain to the matter.

USEPA General Comment #1:  ‘Language exists in the ROD to the effect that a risk exceedance due to exposure to Area C groundwater is the single measure driving a remedial action at this site. EPA disagrees with this position and maintains that by virtue of the fact that Picatinny is located over a sole source aquifer (see Federal Facility Agreement, Section 5.12, under Findings) that bears the designation of at least a Class IIA current source of drinking water classification. According to the NCP, “EPA expects to return usable ground waters to their beneficial uses wherever practicable, within a timeframe that is reasonable given the particular circumstances of the site.”  Based on aquifer designation, the beneficial use of groundwater located under Picatinny is drinking water. Therefore, EPA requests that this policy be included in discussions regarding what measures drive groundwater cleanups at Picatinny’. 

Picatinny Response: 

“The issue raised in Comment #1 has been the subject of the Mid-Valley dispute between USEPA and the Army.  Since the Area C Groundwater ROD was drafted, the dispute between the USEPA and Army regarding the Mid-Valley Groundwater Operable Unit has progressed

 

 

and both parties have agreed that both measures of risk and groundwater ARARs can be drivers for action for Picatinny groundwater operable units.  Therefore, the Area C ROD will be modified to be consistent with the Mid-Valley FS.  Specifically, the Area C ROD will state that groundwater ARARs are one of the drivers for remedial action at Area C”.

USEPA Comment:  “The selection of this Remedial Alternative relies on the continuation of the reported trend of decreasing concentrations of these two COCs. Because a mechanism of natural attenuation for these two COCs has not been discussed, it would be prudent to have a more complete discussion of what approach would be used in the event that concentrations of these two COCs, above risk-based limits, reaches beyond the limits of the current CEA”.

Picatinny Response: 

“The Army is committed to correcting any deficiencies in the remedy should they arise.  The mechanism for identifying potential deficiencies in the remedy is the 5-year review.  This mechanism will be detailed in the Long Term Monitoring Plan for Area C Groundwater. Trigger levels for the re-evaluation of the effectiveness of the remedial alternative will be presented in the LTMP, which will be developed during the RD. The trigger levels will indicate if a more aggressive remedial alternative should be considered. In the event deficiencies in the remedy are identified, the need for action will be evaluated at that time.  Without knowing the nature of a hypothetical deficiency in

 

 

the remedy or potential technological advances, the reaction to that deficiency cannot be effectively determined at this time”.

Other comments related to the time frame to attain cleanup levels and contingencies should the remedy fail.  These comments are presented below.

USEPA Comment:  “Has there been any effort to quantify the time it will take to reach site clean up levels in the Area C groundwater unit? If not, please explain why”. 

Picatinny Response: 

“The time it will take to reach site clean up levels in the Area C groundwater operable unit has not been quantified.  Because of the nature of the groundwater exceedances in Area C any estimated timeframe will have limited accuracy. However, in order to meet the remedial action objective of protection of human health, the remedy will be continued until contaminant levels are shown to allow unrestricted use of the groundwater, as noted in the Proposed Plan. Cessation of monitoring will be allowed only after the tenants of the exit strategy are met. The details of the exit strategy will be finalized in the RD phase”.

Many other comments were editorial in nature necessitating changes in wording or tables. Of these one noteworthy comment was the following statement that affirms the RAB’s participation in the oversight of environmental remediation activities at the  Arsenal.

NJDEP Comment:  “Picatinny intends to give the PAERAB an opportunity to review well locations and parameters during the RD process. This is acceptable. “