PERMFILE41376

• Permit No: C1981010
• IBM Index Class Name: Permit File
• Doc Date: 3/20/1990
• Doc Name: Annual Hydrology Report
• Section_Exhibit Name: Appendix W 1989 Report Section 2.0
• Media Type: D
• Archive: No

• a. Ground Water
(1) Static water level graphs.
(2) Salinity graphs.
(3) Piezometric surface maps
for the major aquifers.
(4) Water quality tables.
b. Surface Water
(1) Water quality figures and tables.
(2) Flow charts.
(3) Flow vs TSS vs time graphs.
(4) Conductivity vs flow vs time graphs.
2.6 Trends
Sections 2.0-3.5
Appendix A
Appendix B
Maps 2.1-2.3
Appendix B, Table B1,
page B-39-117
Sections 4.0-5.3
Appendix C Table Cl,
page C-31-52
Appendix C Figures Cl-C6
Appendix C Figures C7-C18
Appendix C Figures C19-C30
The trends for impacts on the hydrologic systems at Trapper Mine are discussed in Sec-
tion 6.0 of Hydro Engineering's report.
Basically for the groundwater regime, the natural variations in aquifer recharge continue
to account for most of the changes in Trapper monitoring wells. Wells in close proximity
to mining do show some impacts but they are within the natural variations.
Specifically upgradient mining, close to monitoring wells in undisturbed areas, has con-
tinued to affect piezometric water levels but not to the detriment to the ground water
system. The increased permeability of the backfilled areas has both increased and/or
decreased pre-mine water levels depending on their location. Wells installed in the
backfilled areas will probably never recover to undisturbed conditions but that same
permeability will increase water levels and potential yields in down gradient wells and
aquifers.
Water quality parameters are more affected by natural recharge than mining. The
salinity levels in the backfill welts are similar to the native aquifers. There have been
some TDS level increases but generally not out of the natural range nor that pose risks.
All pH values are within natural and acceptable ranges.
More information on Radium levels is still needed. Mast baseline levels are acceptable
but outliers at various sites without direct correlation to specific aquifers or sampling
periods require more study. Radium 226 concentrations are naturally high in the area of
Trapper Mine. Trapper has initiated QA(QC sampling splits to verify lab analytical
results and is working with Hydro Engineering to evaluate the reasons for variations in
Radium concentrations.
~~
For the surface water regime, Trapper's sedimentation systems are working properly.
There were no violations or excursions for effluents discharged in 1989 with the excep-