HANFORD NORTH SLOPE AREA
BACKGROUND AND STATEMENT OF ISSUES
This memorandum is in response to your request to provide comments to the U.S. Environmental Protection Agency on a proposed expedited response action for the North Slope Area of Hanford Nuclear Reservation (1). The Agency was provided with a copy of the North Slope Expedited Response Action Proposal (DOE/RL-93-47)(2) to review.
The North Slope area, located on the northern bank of the Columbia River, is across from the Hanford reactor facilities. It includes the 100-Isolated Unit-3 Operable Unit.
The goal of the expedited response action is to characterize and remediate potentially hazardous wastes in areas accessible to the public. Potential hazards include refuse disposal areas, dry wells, acid neutralization pits, the 2,4-D disposal area site and ordnance and explosive waste(3).
The proposal lists three potential future uses for the North Slope area: (1) continued current use as a wildlife refuge under DOE ownership, (2) use as a National Wildlife Refuge under the U.S. Fish and Wildlife Service, or (3) unrestricted use which would include agricultural and residential development(4),(5).
Data on soil in the appendix of the proposal are from samples varying from 3 to 16 feet below the surface(6). Possible exceptions may be samples from the H-90 area with concentrations as high as 690 ppm arsenic and 1200 ppm lead(7).
The water-master for the Columbia Irrigation District of the Bureau of Reclamation has been using water from his residential off-site well, which taps the unconfined aquifer north of the Columbia River(8). However, there are no groundwater sampling data. There are no sampling data for surface water in the irrigation ditch or the ponds in the North Slope area. Cleanup goals are not listed in the proposal, but will be developed later as contaminants are identified(9).