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TPHD, with one relatively elevated level of 33,000 micrograms per liter(ug/1) TPHD in B-2 in a downgradient location. BTEX, MTBE and related oxygenates were not revealed in any groundwater sample. Wright drilled and sampled five (5) additional borings (B-5, B-6, B-7, B-8 and B-9) in October 2008. Soil and groundwater samples were collected and analyzed only for TPHD since previous analysis had shown that gasoline and related fuel compounds had not been detected. TPHD dissolved concentrations were relatively low in groundwater. Boring B-6 drilled adjacent to Boring B-2 showed only 170 Ug/1 (compared to 33,000 Ug/1 at B-2 in 2003) a significant decrease. The laboratory reported that the TPHD was higher boiling than typical diesel fuel. In our opinion a large contaminant problem is not indicated from this data, and only a small dissolved residual and possi y r e H,L�: ume is present. On the basis of a data review d dis ss s wi staff, EHD requested that one (1)groundwater monitoring well be installed near Wright boring B-5. This new well is used in conjunction nearby existing WWTP groundwater monitoring wells MWHP-5, MWHP-6, MWHP-7 and MW HP-8 installed by CH2M Hill for groundwater direction plots (see Figures 1 and 2). It is our understanding from a limited review of the existing CH2M Hill wells that they are screened in the same aquifer strata as that investigated in the area of the proposed new monitoring well by Wright in 2003 and 2008. The new well was designated "MWWES-1" to avoid confusion between this monitoring well and the existing CH2M Hill monitoring wells. The CH2M Hill wells (MWHP-5, MWHP-6, MWHP-7 and MWHP-8) are used for water level measurements only. These measurement data are used to plot groundwater flow contours together with well MWWES-1. The new well was sampled for both water level measurement and chemical analysis program discussed below. The existing CH2M Hill wells are not sampled for groundwater quality for this Wright groundwater monitoring program. 2.0 Monitoring Well Water Level Measurements and Sampling The contract sampler developed the well MWWES-I on September 9, 2009. The monitoring well was first purged using calculated well volumes based upon the depth to water in each casing prior to sampling. Depth to groundwater measurements were made to the nearest one-one hundredth of one foot, and also checked for the presence of separate phase product. As each purge volume is removed, measurements of pH, electrical conductivity, turbidity, and temperature will be taken until these parameters stabilize over two measurements, which are interpreted to indicate aquifer water entering the casing. The well was allowed to stabilize to about 80% of its initial water level before sampling. The groundwater sample was carefully collected with a clean disposable PVC bailer and poured with minimum cavitation and minimum headspace into the appropriate laboratory prepared containers. The water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice for transport to the laboratory. Upon completion of monitoring water level measurements and/or well sampling, each well was closed and locked. Well purge Page 2 of 7