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Forward's logs of liquid levels in the two Class 11 impoundments were reviewed for the period between 2005 and 2012. As would be expected, the maximum depth of leachate in the ponds occurred at the end of the wet season, generally in May. Leachate levels in the ponds decreased through the summer due to evaporation. In general, the ponds were empty or near empty by the fall or early winter. The maximum depth of leachate occurred in May 2006 and was 7.5 -ft in WMU F -North and 7.85 -ft in WMU F -West. 2.0 POND DEPTH MANAGEMENT PLAN As noted in Table 1, precipitation and leachate generation increase liquid levels in WMU F -North an average of 2.73 -fit and in WMU F -West an average of 3.51 -ft. The average value for precipitation was obtained from the Stockton WSO climate station for a period from October 1948 to March 2013. The average leachate generation was based on site records from 1991 to 2012 and includes the EI Nino years of 1996 and 1998. Evaporation decreases the liquid level by an average of 6.53 -ft in both ponds. Therefore, evaporation exceeds the total leachate generation and precipitation. Because the cannery season starts in .lune, when the ponds have typically been near their peak levels, Forward is proposing to manage pond capacity by maintaining sufficient freeboard through the cannery season to account for the following year of precipitation and leachate gencration. This Vvould mean that, including the required two -ft of freeboard in each pond, the total freeboard in NVMU F -North would be a minimum of 4.73 -ft (2 -ft Plus 2.73 -ft) and the freeboard in WMI! F -West would be a minimum of 5.51 -ft (2 -ft plus 3.51 -ft). For WMU F -North, the maximUmn depth of liquid in the pond would be 5.27 -ft (10 -ft pond depth minus 4.73 -ft) and for WMU F -West would be 9.74 -ft (15.25 -ft pond depth minus 5.51 -ft). Since 1999, when WMU F -North was constructed, Forward has had more than sufficient capacity to manage leachate onsite. With the addition of WMU F -West in 2003, Forward is also likely to have sufficient capacity to accommodate precipitation and leachate generation in future peak years. However, if necessary during a future peak precipitation and leachate generation year, Forward will dispose leachate at the Stockton Wastewater Treatment Plant, as was done during the El Nino year of 1998. 3.0 Class II Impoundment Compatibility Forward performed an analytical test of the cannery rinse water in 2011. Value Engineering evaluated the results of the cannery rinse water analytical tests and found that they were compatible with the Class 11 impoundment liner. The Value Engineering report, which includes the analytical test results, is included in Attachment B. 4.0 Odor and Sludge Accumulation Management Plan In general, Forward manages onsite odors in accordance with its Odor Management Control Plan (see Attachment C). For the cannery rinse water, special controls will be implemented due to the potential for cannery rinse water to be particularly malodorous.