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2005 AHR Page4 Whole Effluent Toxicity (WET) tests were continued this Year. The acute test involves subjecting fathead minnows to various dilutions of effluent in receiving water for 4 days and subjecting Ceriodaphnia dubia to various dilutions for 2 days. The tests look primarily at mortality during the test period. Data page SL-5 includes summaries of the percent survival at the individual effluent dilution ratios for the Year. The survival rates for all samples taken this Year were in compliance with the discharge permit requirements. Ground Water The ground water monitoring points on Cottonwood and Rapid Creeks were monitored twice during the Year. Results of the monitoring are listed on data page GA-2. Diagrams G05-1 thru 3 shows a graphical representation of the depth to water for these wells since monitoring began in 1984. Table G05-1 was prepared to show average water levels in the spring and fall to correspond to high and low water levels in the adjacent creeks respectively. Piezometers CRDA-01 thru 06 at the Cameo Refuse Disposal Areas (CRDA) No. 1 and No.2 continued to be monitored quarterly. Data page GG14 includes measurements for this Year. A graphical representation of the water level elevations in the CRDA Piezometers is shown on • Diagram G05-4. The water levels in CRDA-01 and CRDA-01A were relatively stable this Year The results of water level measurements at the unit train loadout this Year are listed on Data page GB-2. Diagrams G05-5 and 6 are graphical representations of water level elevations in these piezometers. Table G05-2 was prepared to show statistics on these water levels corresponding to high and low flows in the adjacent river. Quality information is presented on page GD-13. Piezometers CRDA-02, 03, 04, 05 and 06 have been damp to dry for the past four years (2002 - 2005). The nested PZ-# piezometers showed only slight variation during the Year. The water levels in the PZ-# piezometers were all below their critical depths. A graphical representation of the water levels in the nested piezometers is shown on diagrams G05-7, 8, 9 and 10. A former mine dewatering hole (N-1) located at the North Decline area of the mine is used to monitor the water level in the abandoned portions of the Roadside South Portal. Since discharge point 016 was put into service, the water level in N-1 is virtually constant and it is expected to stay at an elevation of about 4758. The results of monitoring N-1 are presented in Table M05-2. In order to characterize the Rollins Sandstone two surface and two underground wells were installed during June 1997. The surface wells were installed at the north decline and the unit • train loadout. The underground wells were installed in the North and South Portals. Depth to water ranged from 56.5 feet below grade in the North Decline well to artesian in the North Portal well. Monitoring of these wells will continue in accordance with permit requirements. Rollins-1