Cal. Code Regs. tit. 23 § 3959.7
The Regional Water Quality Control Board, Lahontan Region (Lahontan Water Board) adopted Resolution No. R6V-2015-0005 on February 11, 2015, amending the Water Quality Control Plan for the Lahontan Region (Basin Plan). The State Water Resources Control Board approved the amendment under Resolution No. 2015-0063 on October 7, 2015.
Certain ground waters beneath Naval Air Weapons Station China Lake (NAWS China Lake) are not suitable for municipal or domestic (MUN) uses, including drinking, because they contain naturally high concentrations of total dissolved solids (TDS), arsenic and other inorganic compounds. The primary reason for proposing removal of the MUN beneficial use at this time is in response to a request by the Navy to aid in its groundwater remediation efforts at NAWS China Lake.
The ground waters proposed for de-designation are those located beneath the Salt Wells Valley and those within the shallow groundwater in the eastern Indian Wells Valley groundwater basin. Both of these areas are located entirely within the boundaries of the NAWS China Lake. No changes are proposed to the other designated beneficial uses for ground waters of the Salt Wells Valley and Indian Wells Valley basins.
In 1989, the Water Board amended its 1975 Basin Plans to designate MUN uses for almost all surface and ground waters in the Lahontan Region, including inland saline lakes and geothermal springs. The rationale for this action was that, due to the scarcity of water supplies in much of the region, it might be feasible and desirable to treat and use even poor quality waters in the future. The Water Board also lacked the staff resources and water quality data necessary to assess all water bodies in the Lahontan Region on a case-by-case basis for their suitability as drinking water sources.
The Navy has conducted multiple studies of the NAWS China Lake including hydrogeological studies, geochemistry of the groundwater, and a water treatability analysis. A summary of the pertinent technical assessments are included in the Staff Report in Enclosure 2. Over several years, Water Board staff has participated in the Navy's studies by reviewing plans and reports, consulting with Navy's consultants and groundwater management agencies in the Ridgecrest area, and requesting information from the Navy specific to de-designation criteria.
Water Board staff reviewed and evaluated the information provided and completed its own analysis including consideration of alternatives. Based on the various hydrogeological characterizations, water treatability analyses, and community input, Water Board staff concludes the information is sufficient and that MUN use de-designation is appropriate.
Cal. Code Regs. Tit. 23, § 3959.7