Demirkanli, D.I., N.P. Qafoku, D.L. Saunders, A.R. Lawter, M.M. Snyder, C. Bagwell, et al.
PNNL-28063, 107 pp, 2018

The 200 West Area pump-and-treat (P&T) system is a key component of the final remedy selected for the 200-ZP-1 Operable Unit (OU), and the interim remedial action selected for the 200-UP-1 OU at the Hanford Site. The facility also receives perched water, groundwater, and leachate from several other contaminated areas within the Hanford Site. Since the use of the P&T system evolved to support remediation activities in other OUs, a study was conducted to determine impacts on the 200 West aquifer where the treated water is injected. A baseline assessment using 20 samples from 3 injection wells measured important parameters such as particle size distribution, moisture content, mineral phase abundancies, pH, extractable elements and contaminants, carbon content, and bacterial types and abundance. Batch experiments were conducted using P&T effluent and representative Hanover groundwater to measure potential geochemical reactions occurring in the aquifer with the injection of P&T effluent. Planned future testing includes column experiments and reactive transport modeling to quantitatively assess aquifer impacts and system performance under the current and predicted future conditions. https://www.pnnl.gov/main/publications/external/technical_reports/PNNL-28063.pdf