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.. y FALL CREEK REPORT OF WASTE DISCHARGE RNGTNERRTNG.TNC:. v— %w Projected wetland loading rates during the months of crush are expected to be higher than the `„ EPA's suggested BOD loading rate of 112 kg/ha-d(100lb/ac-d). However, these rates are well %w within the successful experimental values of 1650 kg/ha-d(1472 lb/ac-d). There are some months with loading rates as much as 6 times the EPA's suggested level, however the average yearly loading rate is 230 kg/ha-d, which is only twice the value and there are many months `w where the loading rate is much lower. This, in addition to the successful values reported by %w Shepherd et al, makes FCE confident that the constructed wetland proposed for Jessie's Grove Winery will perform adequately even under higher flow conditions. FCE also notes that the hydraulic detention time under these higher flow conditions remains higher than six days at all %w times and therefore BOD removal is expected to be high. `. 104w 5.3 Nutrient Uptake The grasses nutrient uptake for the flow rates in the 10-year plan flows was analyzed similarly to `, the current expansion flow rates as described in Section 4.3.4. Table 5.4 presents the potential `w crop uptake of nitrogen for the field grasses based on the amount of acreage to be used at the winery and compares these values to the expected mass of nitrogen applied to the fields from the wastewater. The field was assumed to be planted with bermuda grass. Average total nitrogen in %w the process wastewater and storm water were assumed to be 25 and 1.5 mg/L, respectively. It was also assumed that the wetland would reduce total nitrogen in the wastewater by at least 70%. �w Table 5.4. Comparison of Potential Grass Nitrogen Uptake to Total �fte Nitrogen Applied from Process Wastewater and Storm Water (after Pettygrove and Asano, 1985) Total N Uptake Total N Total Nitrogen `„ Acres in Representative Yield (Ib/ton of Uptake Applied after Crop Production Yield ton/acre tonyield) bs) Wetland Ib/acre `r Grass 0.6 4 2.4 63 151 85 ♦. The comparison indicates that the total amount of nitrogen applied in the wastewater is still %w slightly less than may be required for the grass. This implies that additional nitrogen fertilizer may or may not be needed to satisfy the grasses nutrient requirements, however no downward migration of nitrogen is expected. %w 5.4 Inorganic Dissolved Solids FCE has estimated the potential concentration of inorganic dissolved solids(IDS) applied to the �' 0.6 land disposal system. The final IDS concentration is calculated using mass-balance �h- calculations that account for the amount of water applied from the various sources (wastewater, storm water, direct rainfall) and the associated IDS concentration contained in each source of water. The analysis does not account for supplemental irrigation water that may be applied to the land disposal area during the late spring and early summer when the treated effluent may not t%' provide for an adequate supply of irrigation water to the area. This supplemental water will `w further reduce the concentration of IDS applied to the area. A copy of the calculations is `, presented in Appendix B. The following describes the information used in the analysis. %kW JESSIE'S GROVE WINERY 25 FEBRUARY 2004