An average decrease in water levels of 47.5 feet occurred at CSSA between March 19, 2001 and June 11, 2001. Approximately 6.58 inches of rain fell at CSSA during this time, whereas approximately 10.13 inches of rain fell at CSSA between December 11 and March 19, 2001 when groundwater levels increased 53.19 feet.

The groundwater elevation map for the March 2001 sampling event indicates that the general groundwater flow direction was to the southeast with an approximate gradient of 0.007 feet/feet. Groundwater elevations were relatively even in the central and western portions of CSSA. The groundwater elevation of 1163.6 feet MSL in Well MW4-LGR was much higher than water levels in surrounding wells.

Groundwater elevation variations among Glen Rose and Cow Creek wells in the same cluster were smaller than those observed between Glen Rose and Bexar Shale cluster wells.

Problems with several pumps in new monitoring wells caused aeration of the samples that potentially impacted the VOC results.

Among the newly installed monitoring wells only Well MW5-LGR had VOC levels above the RL with cis-1,2-DCE and TCE concentrations of 1.90 �g/L and 1.70 �g/L, respectively.

VOC concentrations below the RL were discovered in several new monitoring wells. Wells MW5-LGR and MW8-LGR both had a PCE concentration of 1.10 �g/L. Well MW8-LGR also had a sub-RL TCE concentration of 0.18 �g/L.

Well MW6-LGR was also found to have several sub-RL VOC concentrations: a cis-1,2-DCE concentration of 0.26 �g/L, a PCE concentration of 0.50 �g/L, and a TCE concentration of 0.42 �g/L.

The PCE concentration in offsite, downgradient well LS-7 increased slightly during this monitoring event. The PCE level rose from 3.76 mg/L in March 2001 to 4.00 mg/L in June 2001. The TCE concentration in this well remained below the RL at 0.43 mg/L.

MCLs for TCE, PCE, and cis-1,2-DCE were exceeded in Well 16 during the June 2001 monitoring event. The concentrations of these compounds in Well 16 were 73.00 mg/L, 75.00 mg/L, and 73.00 mg/L, respectively. Chloroform and trans-1,2-DCE, which had been previously found in Well 16, were not detected.

Well D had TCE (140.0 �g/L), PCE (110.0 �g/L), and cis-1,2-DCE (130.0 �g/L) concentrations that were above the MCLs.

Wells 1, 9, and 10 did not have any VOC concentrations that exceeded the RL.

Well I exhibited an extremely high and somewhat suspect concentration of zinc at 3470 mg/kg.

The lead AL was exceeded in Wells H, I, and MW3-LGR with concentrations of 0.0459, 0.0349, and 0.0316 mg/kg, respectively.

Well MW8-CC had an iron level of 0.316 mg/L that exceeded the AL. Other newly installed monitoring wells did not contain significant metals levels.

Well 11 could not be sampled due to a malfunctioning pump controller.