see “TECHNICAL REVIEW: GROUNDWATER MONITORING AT AND
NEAR THE PLANNED SALTSTONE DISPOSAL FACILITY
(DOCKET NO. PROJ0734),” May 17, 2018 – linked here
Conclusion: “The Z Area groundwater characterization study documented a plume in SRNS-RP-2015-00902. Based on the information described in this TRR, the NRC staff determined that the number of groundwater monitoring wells do not allow adequate monitoring of the current plume caused by the unintentional release of contaminants from SDS 4. The number and location of groundwater monitoring wells are not sufficient to (1) delineate the lateral and vertical boundaries of the current plume; (2) to identify the current location of the peak of the plume; and (3) to predict the future development of the plume. In addition, the NRC staff is interested in information identifying the source of the current groundwater plume (e.g., did the plume originate from one single event near SDS 4 Cell G in 1997 or has the plume been generated by SDS 4 releasing contaminants due to a series of precipitation events over last 20 years) and where the peak of the plume is currently and in what direction it is heading. Information on the latter would provide insights on how groundwater flows and radionuclides behave in the Z Area and also allow a better evaluation of the potential safety concerns emanating from the plume.”