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Jeffrey K. Tucker 2 February 169 1989 Paddy Creek . Therefore, no surface water samples were taken. County Public Works staff is monitoring the detention basin to determine when the pumps first begin to operate if such an event occurs during this rainy season. In the event that the discharge pumps are triggered and discharge to South Paddy Creeks surface water samples will be taken in South Paddy Creek according to the specifications of Monitoring and Reporting Program Number 87-088. Ground Water Monitoring: The water monitoring reports for the fourth quarter of 1988 for the site are attached (Attachment 1 ) . These reports were prepared by California Water Labs, which was the lab that performed the sampling and analysis, and contain results for all required quarterly sampling. The California Water Lab (CWL) Reports are made up of two reports dated November 22, 1988 and February 7, 1989. These reports relate to field sampling events on November 89 1988 and January 39 1989 respectively. The reason that two sampling events occurred was that California Water Labs erroneously concluded that two monitoring wells, MW-3 and MW-4, were dry while sounding the wells for water level during the November 22, 1988 field sampling event . The CWL finding that MW-3 and MW-4 were dry on November 22, 1988 is considered erroneous due to the facts that: County staff sounded MW-3 on December 21 , 1988 and detected water at elevation -26.38 (U.S.G.S. datum) ; and that upon resampling the MW-3 and MW-4 on January 39 1989, CWL detected water and obtained samples. The monitoring report for the fourth quarter of 1988 is a composite of the two sampling and analysis events performed by CWL for the landfill . Water level measurement used to determine groundwater direction and velocity are taken from depth measurements taken in all four wells by CWL on January 3, 1989. Water quality analysis for quarterly parameters required by Monitoring and Reporting Program Number 87-088 is taken from sample analysis from the November 81 1988 sampling event for MW-1 and MW-2 and from the January 3, 1989 sampling event for MW-3 and MW-4. The CWL reports containing results of field water level measurements and analysis of water quality for samples obtained are Attachment 1 . The water level measurement obtained by CWL were used by the County Department of Public Works to prepare a groundwater level contour map and to determine the groundwater velocity beneath the site. The groundwater level contour map, which is shown as Attachment 2, indicates groundwater direction beneath the site is southerly. The approximate groundwater velocity beneath the site is 76 feet per year (See Attachment 3, "Groundwater Velocity Calculations From Monitoring Wells at the Harney Lane Sanitary Landfill " ) .