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FALL CREEK ENGINEERING,INC. 16. The pH of the process wastewater is not as low as indicated by the RWQCB's "typical values". Therefore, requiring neutralization of pH is not well supported. The concept that applying low pH wastewater will shock micro-organisms in the soil and cause constituents to migrate in groundwater over simplifies the biochemistry of the soil. This does not take into consideration the buffering capacity of the soil and complex soil biota. Please refer to comments pertaining to findings 40 and 41 below. Recognizing that the Winery is being asked to reduce salinity in the wastewater, it is unclear and inconsistent for the Regional Board to require the Winery to install a pH neutralization system. Installing a pH neutralization system will result in the addition of fixed dissolved solids to the wastewater, which may result in degradation of ground water quality. Relying on the LTU to buffer organic acids in the wastewater is a preferred option that will not require the addition of soluble salts and will provide a more reliable operating method to protect water quality: the goal of the Winery and the RWQCB. 30. The well locations shown in Attachment B1 are incorrect. Please review the map provided in the RWD, dated March 2002. 32. The limited groundwater data collected to date does not support the finding that groundwater quality measured in MW3 may indicate that groundwater below the rapid infiltration area is impacted by the discharge of wastewater from the winery. Although MW 1 is far removed from the rapid infiltration area, groundwater quality as measured by total dissolved solids, nitrate, chloride and sodium are equivalent in both MW 1 and MW3. This data indicates that the quality of groundwater measured in MW 1 and MW3 are strongly influenced by intensive agricultural practices in the area. This finding does not reflect that the area has been in agricultural land use for over 100 years and that the presence of nitrate and elevated TDS is most likely a result of these regional land use conditions. If groundwater were impacted by the winery discharge one would expect to observe reduced groundwater conditions. If this were the case nitrate concentrations in groundwater underlying the site would be very low or absent. The finding does not take into consideration the basic groundwater chemistry that would occur from the prolonged discharge of wastewater containing elevated concentrations of sugars and organic acids. FCE agrees that additional groundwater wells and monitoring activities are required to better assess groundwater quality at the site prior to determining if historical and proposed wastewater disposal practices will impact groundwater quality. 40. This finding_notes that acidic soil conditions can be detrimental to land treatment function. While this is true, it is also true that acidic soil conditions will also be detrimental to crop production. Many soils behave like a buffered weak acid that resists sharp changes in pH. This buffer capacity is related to clay content and mineralogy, soil organic matter, and to a degree, salt content. Increases in soil acidity may be related to hydrogen and/or aluminum activity. As the soils proposed for use in the slow infiltration system range in texture from fine sandy loam to clay, there is ample rationale to believe these soils will have an adequate to strong pH buffering 4