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Bert E. Van Voris - 7 - 17 September 2004 Supervising Engineer contained TDS in excess of the Title 22 recommended secondary maximum contaminant level (MCL), but chloride and sulfate below the Title 22 recommended secondary MCLS. The Kagehiro Well sample contained nitrate-nitrogen in excess of the Title 22 primary MCL. The Valley View Thoroughbred Farm Well sample contained TDS, chloride, and sulfate all in excess of the Title 22 uppermost secondary MCLS. Despite the limited nature of the data collected as part of RWR preparation,the RWR characterizes first-encountered groundwater as having a TDS ranging from 1,200 to 1,800 mg/L in Jepsen Ranch area and 2,000 to 2,800 mg/L in the Valley View Thoroughbred Farm area. The RWR presents an analysis of subsurface water movement in the vicinity of the proposed use areas. It identifies the protective features of the proposed recycled water project as low percolate flux, depth to first encountered groundwater (estimated at 85 feet bgs), and recycled water quality. It identifies the various processes expected to occur in the soil profile following recycled water application(e.g.,nitrate loss due to denitrification, crop uptake of nitrate and other IDS constituents,temporary storage of IDS in the root zone and upper vadose zone soils, and natural cycling of calcium and carbonate). It does not, however, project the concentration of IDS and IDS constituents in percolate released to groundwater. Instead, it estimates that, once applied as proposed, it will take about 52 years for percolate containing recycled water to reach first encountered groundwater. It states that Musco will be connected to a municipal treatment plant or supplying recycled water for industrial purposes before this happens. Comment: Target BOD Levels. The target BOD level for reuse, 40— 50 mg/L, reflects a lower quality than that achievable through secondary treatment. Regional Board 26 May 2004 letter cautioned Musco to not propose BOD levels exceeding those typical of secondary treatment. The letter defined secondary treatment as follows: Secondary treatment facilities reflecting decades-old technology typically produce an effluent with monthly average daily and daily maximum concentrations of biochemical oxygen demand(BOD)and total suspended solids (TSS)each not exceeding 30 and 45 mg/L,respectively. Facilities reflecting current treatment technology typically produce an effluent with less than 20 mg/L each of BOD and TSS. The letter advised that(a) "recycled water," as defined in CWC Section 13050(n)), "refers to wastewater subjected to secondary treatment of conventional pollutants to render it suitable for direct beneficial use" and (b)to be deemed a recycled water project, "conventional waste constituents must be subjected to secondary treatment." The letter identified the minimum level of treatment required for a recycled water project as follows: The Water Code does not define the minimum level of treatment necessary for a wastewater to be considered recycled water. However, undisinfected secondary is the minimum required level treatment of wastewater of domestic origin for purposes that do not require pathogen removal, according to State's Water Recycling Criteria(as established in Title 22, California Code of Regulations, Section 60301 et seq., or"Title 22"). Undisinfected secondary recycled water is defined as"oxidized wastewater"(Title 22 Section 60301.900), which is defined as"wastewater in which the organic matter has been stabilized, is nonputrescible, and contains dissolved oxygen" (Title 22 Section 60301.650). Secondary