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For non-parametric tolerance limit analysis, the highest value from the background data set is used to set the tolerance limit. The false positive rate for non-parametric analyses were established from California standards and determined based on sample size, with all false positive rates falling below 3.5 percent. Screened background data from March 2003 through the November 2010 sampling event were used to calculate the intrawell tolerance limits used as the CLs for the routine monitoring parameters for each groundwater monitoring well at the Forward Unit. For the Austin Unit DMP wells, screened background data using background well AMW-2 from March 1991 through the November 2012 sampling events were used to calculate the interwell tolerance limits used as the CLs for the routine monitoring parameters. TREND ANALYSIS For well-analyte pairs that exceeded the respective CL, a temporal trend analysis was conducted to assess if statistically significant increasing or decreasing temporal trends present in the data. Mann-Kendall/Ben's Slope trend analyses were performed by GLA using Sanitas®statistical software, using screened data collected from 2008 to present to evaluate for the presence of significant statistically increasing trends. For CAP wells at the Austin Unit, Mann-Kendall/Sen's Slope trend analyses are performed to evaluate the effectiveness of corrective action measures. Therefore, data collected from 1994, when the GTF began operation, to the most recent sampling event is used to evaluate for the presence of statistically significant temporal trends. Trend analyses calculations are attached. NON-STATISTICAL DATA ANALYSIS For those substances that have no natural background such as VOCs,pesticides, and other anthropogenic compounds, GLA performed the non-statistical "VOC Water" data analysis required by Resolution No. 93-62 of the State Water Resources Control Board,titled"Policy for Regulation of Discharges of Municipal Solid Waste" for VOCs detected less than 10 percent of the time in background samples. Under the VOC Water analysis, a measurably significant indication of release occurs in a given sample when: two or more VOCs exceed their respective Method Detection Limits (MDLs); or one or more VOCs equals or exceeds its respective practical quantitation limit(PQL). 40 C:\2013-0021\Appendix D Stats.doc D-2 Geo-Logic Associates