PERMFILE112377

• Permit No: C1981010
• IBM Index Class Name: Permit File
• Doc Date: 3/15/1996
• Doc Name: Annual Hydrology Report
• Section_Exhibit Name: Appendix W 1995 Report Section 2.0 & Section 2.5
• Media Type: D
• Archive: No

operational until January 1996. An existing Deninger Pit dewatering well (No. 6) was abandoned in early
May.
In 1998, topsoil stripping, followed by drill and blast activities, will remove monitoring wells, GA-1 and
GA-2. These monitoring wells will not be replaced. See Section 2.5 of this report for further information
concerning these two wells. Permit map, M52 will be revised to reflect this change when this TR is
approved.
2.5 1995 Hydrological Data
Hydro-Engineering Inc.'s collation of the 1995 hydrological data for Trapper Mine is submitted as Section
2.5, addressing:
a. Groundwater Sections 2.0-3.6
(1) Static water level graphs Appendix A
(2) Salinity graphs Appendix B
(3) Piezometric surtace maps for the major aquifers Maps 2.1-2.3
(4) Water quality Appendix B
b. Surtace water Sections 4.0-5.3
(1) Water quality figures and tables Appendix C
(2) Flow charts Appendix C
(3) Flow vs TSS vs time Appendix C
(4) Conductivity vs flow vs time Appendix C
• Included with the 1995 Hydrology Report is an index sheet (blue) to keep the basic well data and aquifer
information available to the reader. This index is to be used as the reference and also a "bookmark" as
the section is reviewed.
2.6 Trends
Hydro-Engineering's Section 8.0 discusses the observed impacts on the hydrologic systems of Trapper
Mine. In general, ground water levels and surface water flows were higher than those observed in 1994.
The high precipitation level (148 percent of the historical mean) was the major contributor. Trapper con-
tinues to have little if any effect on the local hydrologic regime.
2.7 Spoil Spring Sampling (1995)
Trapper conducted the annual spoil spring inventory, required by Section 4.8.5.2a, across our mined
areas. No new spoil springs were located and none of the existing spoil springs exceeded the five gallon
per minute flow criteria.
2.8 1995 WET Testing Results
In 1995, six drainages had Acute WET tests performed as required by NPDES Permit CO-0032115.
NPDES sites 001, 002, 008, 011, 013, and 015. In all cases, the discharge showed no acute toxicity to
the test species. Summaries for the tests are enclosed.
In accordance with our NPDES permit, only those drainages that may receive pit dewatering are required
for WET testing.
LWH 3198
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