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Messrs. Sutton and Teed-Bose - 2 - 17 July 2001 collected from Patterson Pass Road ditch; the source of the water in the ditch where Sample 2A was collected is unknown but is apparently not groundwater. Based on the limited data available (i.e., a single sample event performed 18 May 2001) the acceptability of shallow groundwater samples as a surrogate sample for the agricultural drains is questionable. Agricultural drain samples (Samples IA, 2A, 3A, and 4A) were compared to the nearest shallow well sample (Samples MW-1S, MW-2S, MW-3S, and MW-4S). The data for electrical conductivity, nitrate, and total nitrogen are plotted on the enclosed charts. Comparison of the analytical data for the shallow wells and the agricultural drains reveals significant differences. Comparison of the nitrate, EC, and total nitrogen concentrations reported in the upgradient shallow well samples MW-1S and MW-2S with the corresponding concentrations in agricultural ditch Samples I and 2A reveals significant differences. This implies that the source of water in the ditch is not shallow groundwater and indicates that more representative sampling locations are needed. Comparison of the nitrate, EC, and total nitrogen concentrations reported in the downgradient shallow well samples MW-3S and MW-4S with the corresponding concentrations in agricultural ditch Samples 3A and 4A reveals more consistent concentrations, with the exception of EC which is notably higher in the agricultural ditch samples. It is recognized that there are few locations to collect surface water in upgradient locations, however, inappropriate data collection does not adequately characterize site conditions prior to wastewater application. Review of this data indicates the agricultural ditch and shallow well monitoring performed to date does not conform to the requirements in MRP No. 98-109. Shallow Groundwater Monitorinz Wells The MRP requires 12 months of background data to be collected prior to beginning application of wastewater. Review of sampling performed to date indicates sampling has not been performed as required by MRP No. 98-109. Poor recovery in the wells have been blamed for the missed sample events. However, the submitted data shows that groundwater does recover in the wells prior to the next regularly scheduled sample event. To date, Wells 2S, 3S, and 4S did not contain sufficient groundwater to collect samples in two of four sample events after purging was performed. Well 1 S did not contain sufficient groundwater to collect samples in one of four sample events after purging was performed. In the 6 June 2001 Quarterly Report, Condor proposes to return to the shallow wells which purge dry five days after purging to collect grab samples. This procedure is acceptable and shall be implemented immediately. Conclusions and Requirements The monitoring that has been performed to date is not consistent with the requirements of the MRP No. 98-109. In all future monitoring events during the characterization phase of sampling, all monitoring wells shall be sampled and agricultural drain samples from the ditches shall be collected for characterization of the site. CAProject FilesNSitesNountain House\SuttonBose0716O1.doc