Cal. Code Regs. tit. 23 § 3991.1
The California Regional Water Quality Control Board, San Diego Region, adopted Resolution No. R9-2015-0008 on April 15, 2015, amending the Water Quality Control Plan for the San Diego Basin (9) (Basin Plan). The State Water Resources Control Board approved the amendment by adopting State Board Resolution No. 2015-0066 on November 17, 2015.
The purpose of this Basin Plan amendment is to revise several chapters within the Basin Plan. The nitrate water quality objective for groundwater was made consistent with the allowable maximum contaminant level for drinking water at 45 mg/L nitrate as NO3 in all hydrologic areas/subareas with numeric objectives, except in the Warner Valley Hydrologic Area. Warner Valley's freshwater replenishment beneficial use designation for groundwater precludes raising the nitrate water quality objective. The Basin Plan amendment revises existing provisions for regulation of onsite wastewater treatment systems and incorporates the provisions of the State Water Resources Control Board's Water Quality Control Policy for Siting, Design, Operation, and Maintenance of Onsite Wastewater Treatment Systems. Implementation provisions were added for the nitrate groundwater quality objective to protect surface-water quality where groundwater and surface water are interconnected. An implementation provision prohibiting private ownership of community sewerage systems was removed from the Basin Plan. Other revisions also included addition of descriptions of current statewide policies, deletion of expired conditional waivers, and other minor non-substantive changes.
Cal. Code Regs. Tit. 23, § 3991.1