SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

ORDER NO. R5-2002-0148 - 6 - INFORMATION 6 - INFORMATION SHEET MUSCO FAMILY OLIVE COMPANY AND THE STUDLEY COMPANY WASTEWATER TREATMENT AND LAND DISPOSAL FACILITY SAN JOAQUIN COUNTY do not hinder crop growth. Because the DIS loading rate exceeds the crop uptake rate,it is anticipated that leaching of DIS will result in interim soil attenuation of the DIS and eventual groundwater degradation with continued application. This application procedure is not sustainable with nondegradable constituents. Loading rates must be balanced with uptake rates to protect groundwater quality, and therefore the 1,500 mg/l effluent limit for TDS is necessary. The Discharger states the BOD limits presented in the WDRs are overly restrictive and that higher loading rates have been employed at land application areas. Staff disagree that higher loading rates than published in the tentative WDRs would acceptable based on the Discharger's plan to limit treatment of BOD by mechanical treatment equipment and instead rely upon land treatment of BOD constituents. Land treatment is an effective treatment mechanism,however, overloading the land can result in generation of odors. The discharge has resulted in the generation of nuisance odors at the facility and staff has received numerous complaints,the most recent on 29 August 2002. Staff believes the appropriate BOD value that should be selected from Pollution Abatement is 100 lbs/acre-day. It is noted that the limit published in Pollution Abatement is for the summer season when conditions for land application are favorable. The Discharger is likely to discharge wastewater all year round,when conditions are not optimum. This limit published in the tentative WDRs should be protective of groundwater quality and crop health and should not generate nuisance odor conditions. This position is based on the staff s experience and the loading rate guidance presented in Small and Decentralized Wastewater Management Systems (Crites and Tchobanoglous, 1998) which states that loading rates for BOD often exceed 100 lb/acre day and occasionally exceed 3001b/acre•day; odor problems are avoided by providing adequate drying times between wastewater applications; and loading rates beyond 450 lb/acre-day of BOD should generally be avoided unless special management practices are used. Because of the close proximity of residential areas and the limited land area available for wastewater application, BOD loading rates that require special precautions are not appropriate in this case. Pollution Abatement also states if the BOD loading is too great, the soil will become anaerobic and the crop and treatment process will fail, but that higher loading rates are possible if the site is irrigated for only a few weeks each year and is well maintained. The Discharger's facility operates 365 days a year, so the application areas will not have the opportunity to rest. Because of the limited land area available there are no alternative application areas to discharge the water to if a system upset occurs." The Discharger is required to continue characterizing groundwater quality and to begin characterizing the quality of the percolate below the land treatment units. Percolate samples will be collected by pan lysimeters both in areas of land application and areas outside the land application limits. Groundwater monitoring wells will monitor the first saturated interval;percolate samples will be monitored by pan lysimeters installed at a depth of five feet. If groundwater or percolate quality is degraded,the Discharger must take steps such as reducing loading or improving cropping to protect groundwater quality. NUISANCE ODOR CONDITIONS The Regional Board has received numerous odor complaints regarding the land application areas. An adjacent landowner described the nuisance odor conditions at the 6 June 2002 Regional Board meeting.