ARCHIVED REPORTS UIC PERMIT APP - Laserfiche WebLink

Home Browse Search

HydroScience Engineers, Inc. '4q STRATEGIC WATER SOLUTIONS 221 Gateway Road West,Suite 403 Napa,CA 94558 T:707.254.1900 1 F:7072 541901 www.hydroscience.com January 22, 2007 Northern California Power Agency Attention: Steve Royall PO Box 1478 12745 N. Thornton Road Lodi, CA 95241 SUBJECT: NCPA CT-2 Discharge Characterization Lodi,San Joaquin County Dear Mr. Royall; HydroScience Engineers (HSe) was hired by the Northern California Power Agency (NCPA) to assist in responding to a request from the City of Lodi (City) for a chemical characterization of the water discharged from the NCPA CT-2 facility in Lodi to the City's White Slough Water Pollution Control Facility(White Slough WPC-F). The first set of required analyses was received by HSe on October 11, 2006. A full review of all laboratory results indicated that some of the results did not conform to the lab's QA/QC standards. It was decided to re-sample for questionable analytes. Additional samples were collected in November, and the final lab results were received by HSe on January 2, 2007. This letter summarizes all analytical data for the full suite of water quality parameters requested by the California Regional Water Quality Control Board—Central Valley Region in Sacramento(Regional Board). This letter, with our August 9, 2006 letter containing information requested by the City for the City's response to the Regional Board,provides a complete response to the City's requests for information about NCPA's operations. The parameters for the water quality characterization were specified by the Regional Board in a letter from the Regional Board to the City dated April 21, 2006. The parameter list specified by the Regional Board for the water quality characterization consisted of: (1) Chemical oxygen demand; (2) Residual chlorine; (3) Priority pollutants(December 2001 revision of the Regional Board 13267 list); (4) Process chemicals listed in the April 5, 2006 facsimile communication from NCPA to the Regional Board, and (5) Three species chronic toxicity testing using the species and dilution series described in Order 5-00- 031. The April 21, 2006 letter also asked for discharge flow rates and, if intermittent, the temporal pattern of the discharges.