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The level increase occurred during the third quarter of 2003 and was not detected in well 21- 4DXdue to an instrumentation problem with the electronic level probe. Trouble shooting of the data collection on this probe was first diagnosed as a communication malfunction at the surface terminal not allowing proper down load of the data. It was later determined that the problem was in the down hole probe and a new probe was ordered and installed. Operations personnel take a monthly measurement of all monitoring well water levels and record them on a log sheet. This information was filed but the change in level on well 21-4DX was not flagged until after the fact. The level in well 21-4DX has normally ranged from 210 to 220 feet from surface. The manual measurement on well 21-4DX on June 8, 2003 was 220.45 feet. The level was again measured on July 5, 2003 at 164.66 feet and on July 8, 2003 a new electronic probe was installed at a level of 165 feet. Since various personnel were involved in these activities no one picked up on the unusual change in the well level. The original probe cable was 240 feet in length and was special ordered for service in well 21-4DX. The replacement probe was ordered at the standard shelf item length of 165 feet. Just by chance the level measured in the well just prior to installation of the new probe coincided perfectly and the probe was installed and put into service. The range on the probe is 20 feet. The level in well 21-4DX continued to increase and when the level reached the maximum range of the probe which was 145 feet from surface the signal from the probe reached maximum out put and the readings inaccurately indicated that the level was stable. On August 3, 2003 a manual measurement of well 21-4DX indicated a level Of 113.89 feet. This data was recorded and filed. On September 1, 2003 a manual measurement of well 21-4DX indicated a level of 220.45 feet which appears to have been an erroneous reading. As part of the expanded investigation surrounding balance and pressure upsets experienced in the eastern portion of the lower well field a new series of manual measurements were made on the monitoring wells. The manual measurement taken on well 21-4DX on October 14, 2003 indicated a level of 89'. The depressurization process has been started on the wells that were placed on stand by and a daily manual measurement of the level in the dissolution surface monitoring wells 21-3D, 21-4DX and 29-4D will be taken to track any changes in levels. The electronic level measurement in well 21-4DX will be revised to allow continuous read out in the plant control room with an alarm to notify operations personnel of any increases or decreases in the well level so that appropriate actions can be taken. The monthly monitoring well samples for October 2003 are currently being collected and analyzed. The analysis on these samples will be forwarded to the BLM, EPA and CDMG as soon as the data is available from the laboratory. American Soda is continuing its investigation of the wells that have been shut-in to determine what actions are necessary to preclude any further effects on the overlying strata of the well field. As this study progresses we will update the agencies of any findings and will develop a well by well methodology for either returning the well to operation or permanently removing the well from operation. If you have any questions or concerns regarding this report please contact me at 970-285- 0407.