Laserfiche WebLink
LCRS Design - Area 28 <br />Foothill Sanitary Landfill <br />increase, which provides a buffer to large storm events and generally leads to attenuated peaks <br />in leachate production. After closure construction, leachate production is expected to be <br />greatly reduced. This critical situation was evaluated for both side slope and base LCRS <br />configurations. <br />The proposed LCRS in Area 213 was evaluated for the critical landfill profile with respect to <br />leachate generation, consisting of the active cell condition with a 15 -foot waste thickness. <br />Additionally, the Area 213 LCRS was evaluated at final waste filling thicknesses of 145 feet <br />(current master plan) and 300 feet (conservative future waste fill thickness) to understand the <br />required design transmissivity of those configurations and assess the availability of products <br />meeting those requirements. <br />4.4 Climate Input <br />Similar to Geosyntec (2014) for Area 2A, GLA generated 30 years of climatological input based <br />on the HELP model's synthetic weather generator using the default model coefficients for <br />precipitation and temperature based on Fresno and Sacramento, California. The HELP model <br />allows for modification of built-in synthetic weather data using mean monthly temperature and <br />monthly precipitation totals. Raw monthly precipitation totals along with mean monthly <br />temperature data was obtained from the Stockton Fire Station No. 4 (COOP station 048560) as <br />obtained from the Western Regional Climate Center (WRCC) (https://wrcc.dri.edu). <br />Temperature and solar radiation data were also generated based on synthetic weather <br />generation coefficients for Sacramento along with the site latitude. <br />Monthly total precipitation data was downloaded from WRCC and loaded into Microsoft Excel <br />for reduction and selection of precipitation data for use in the HELP model. Specifically, the <br />entire monthly precipitation record for COOP station 048560 ranging from 1906 through 2017 <br />was loaded into Excel for reduction. After loading the data into Excel, it was observed that 1906 <br />through 1925 had significant data gaps and were not used. Additionally, 2011 to 2015 were <br />observed to have relatively significant data gaps, and were also not used. To develop <br />conservative input data for the HELP model's synthetic precipitation generator, the weather <br />station's total annual precipitation data was averaged over 10 -year increments to find the <br />wettest ten year average. The wettest 10 -year average was found to be from 1995 through <br />2004. The monthly totals from those 10 years were then averaged to develop input data for the <br />HELP model. The precipitation data entered into HELP is presented in the table below. <br />TABLE 1- MONTHLY PRECIPITATION DATA <br />YEAR <br />I JAN <br />FEB <br />MAR <br />APR <br />MAY <br />JUN <br />JUL <br />AUG <br />SEP <br />OCT <br />NOV <br />DEC <br />TOTAL <br />1995 <br />8.44 <br />0.43 <br />6.87 <br />1.04 <br />0.78 <br />0.41 <br />0 <br />0 <br />0 <br />0 <br />0 <br />5.86 <br />23.83 <br />1996 <br />4.86 <br />4.87 <br />2.33 <br />1.31 <br />1.62 <br />0 <br />0 <br />0 <br />0 <br />1.70 <br />2.67 <br />6.49 <br />25.85 <br />1997 <br />7.66 <br />0.46 <br />0.08 <br />0.55 <br />0.30 <br />0.14 <br />0 <br />0.11 <br />0 <br />0.37 <br />5.03 <br />2.50 <br />17.20 <br />1998 <br />5.28 <br />9.93 <br />2.57 <br />----- <br />3.23 <br />0.18 <br />0 <br />0 <br />0.07 <br />0.98 <br />2.60 <br />1.08 <br />25.92 <br />1999 <br />3.45 <br />4.05 <br />1.32 <br />1.16 <br />0.24 <br />0.02 <br />0 <br />0 <br />0.28 <br />0.18 <br />1.87 <br />0.31 <br />12.88 <br />2000 <br />6.22 <br />8.34 <br />1.17 <br />1.32 <br />0.73 <br />0.04 <br />0 <br />0.04 <br />0.06 <br />2.79 <br />0.39 <br />0.20 <br />21.30 <br />Project No. AU 17.1254 1 LCRS Design 5 <br />May 2018 <br />