Army Revises Groundwater FS to Address Impasse with Partners

Dan Noble: USACE Baltimore continues to monitor the disagreement between USACE HQ, the EPA and the DC Department of Energy & Environment (DOEE), and will update the RAB as a future agenda topic.  USACE Baltimore also continues to address the comments received from the regulators on the draft Groundwater Feasibility Study.  Once the comments have been addressed and the Groundwater FS has been finalized, the next step in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process is the Groundwater Proposed Plan (PP) ... The first step in the process is to get to the point where USACE Baltimore can finalize the Groundwater FS with DOEE and EPA.  USACE Baltimore continues to work on that and expects, hopefully, by the end of January or early February to have a new submission of the Groundwater FS back to DOEE and EPA.

Allen Hengst: So you are changing the Groundwater FS in response to objections?

Noble explained that USACE is adding an alternative to the various alternatives listed in the Groundwater FS.
Spring Valley FUDS
RAB Meeting Minutes
January 9, 2018 (pg.6)

Army says perchlorate can't be treated in-situ due to arsenic.

USACE Baltimore provided a brief update on the status of the Groundwater FS … USACE Baltimore knows that EPA has a different opinion of whether there is a need to restore the groundwater or not.  The response given to EPA was that the CERCLA requires USACE to be protective of human health and the environment and that land use controls do that task.  EPA does not agree with that.  That is a fundamental difference of opinion.  EPA will also still have questions about or perhaps not agree with the premise* that perchlorate cannot be treated because of the arsenic.  EPA does not necessarily agree that is the case.  EPA Region III believed the arsenic in this case is a minor issue.  The arsenic level hovers around the Maximum Contaminant Level (MCL), and is likely not a plume.  
Spring Valley FUDS
Partnering Meeting Minutes
August 3, 2017 (pgs. 8 - 9)

* Perchlorate can be remediated in-situ through inducing reducing conditions, and there are certain microorganisms that will degrade perchlorate.  For arsenic, oxidizing conditions are preferred; not reducing conditions.  When reducing conditions are present at sites such as landfills, where organics are released and cause reduction, arsenic is frequently mobilized.  This presents a quandary for developing an in-situ treatment for perchlorate that is compatible with arsenic.
Spring Valley FUDS
Partnering Meeting Minutes
April 20, 2017 (pg. 15)