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• The 1999 survey monument information, certifications and piezometer well information is provided in Exhibit 6. Section 16 Excess SRoil Fill. The location of the survey monuments and monitor well is shown on the Exhibit 9 - 1999 Annual Re orz rt MaR. 1. S,~~v Monuments -The survey information consists of the survey of the four monuments accompanied with corresponding diagrams to provide an analysis of the results. The surveys indicate the Fill has settled from 1.03 feet to 2.13 feet with a corresponding lateral movement of 0.33 feet to 0.96 feet. The data suggests nothing more than the anticipated amount of settling and consolidation of the Fill. 2. Piezometer Well -The piezometer well was established in late 1994. A water level had originally been detected at the 60-foot depth, corresponding to the level at which the drill penetrated consolidated material underlying the rock drain. We interpreted the water level to be located at the interface of the bottom of the rock drain and the underlying strata. Subsequent monitoring in 1999 has shown the water level to remain consistently in the 58.3 to 59.3 foot depth range. The data suggests that there is no development of a perched water zone within the Fill. 3. No springs or seeps have been noted associated with the Fill. In summary, the monitoring suggests that, during 1999, no significant changes have occurred in the Section 16 Fill and the Fill is performing according to the approved design. ' • C. West Pit Fill Requirements The West Pit Fill is presently under construction. All construction reports and quarterly Certifications aze to be forwazded to the Division until construction is completed. Nine survey monuments have been installed and Colowyo has committed to quarterly monitoring. The piezometer well was installed on June 25, 1996 and the completion report forwazded to the Division. The piezometer well will be monitored quazterly. All monitoring reports aze to be submitted to the Division in the Annual Reclamation Reports. During 1999 Colowyo received approval of Technical Revision 48 to modify the footprint of the Fill. The change was made necessary to 1) modify the placement of fill to avoid azeas of instability in adjacent natural hillslopes of the E. Taylor draw and 2) to correct a computer generated error in the postmining topography. The 1999 construction of the Fill proceeded in accordance with the revised plan. Copies of the construction reports and certifications aze found in Exhibit 7. The reports indicate the • construction of the Fill is proceeding according to the approved plan. 6