2022-11-07_PERMIT FILE - M2022001 ‎(11)‎

• Permit No: M2022001
• IBM Index Class Name: Permit File
• Doc Date: 11/7/2022
• Doc Name Note: Exhibit G - Water Information - Gilcrest Area Alluvial Groundwater Model
• Doc Name: Adequacy Review Response
• From: Red Tierra Equities, LLC
• To: DRMS
• Email Name: PSH
• Email Name: JLE
• Media Type: D
• Archive: No

TABLE OF CONTENTS
Paae
1.0 INTRODUCTION.............................................................................................................................................1
2.0 AREA GEOLOGY............................................................................................................................................1
3.0 SITE GEOLOGY..............................................................................................................................................1
4.0 EXISTING GROUNDWATER CONDITIONS...................................................................................................2
5.0 GROUNDWATER MODEL..............................................................................................................................3
5.1 Regional Topography........................................................................................................................3
5.2 Bedrock Surface................................................................................................................................3
5.3 Hydraulic Conductivity.......................................................................................................................4
5.4 Specific Yield.....................................................................................................................................4
5.5 Boundary Conditions.........................................................................................................................4
5.6 Internal Influences.............................................................................................................................5
6.0 MODEL SIMULATIONS...................................................................................................................................6
6.1 Existing Conditions............................................................................................................................6
6.2 Slurry Wall Installation.......................................................................................................................7
6.2.1 Monarch Mountain Minerals and Aggregates Site Impacts......................................................8
6.3 Mitigation Alternatives.......................................................................................................................9
6.3.1 Phase 1 Mitigation..................................................................................................................10
6.3.2 Phase 2 Mitigation..................................................................................................................11
6.3.3 Mitigation With Recharge.......................................................................................................12
7.0 CONCLUSIONS............................................................................................................................................13
8.0 BIBLIOGRAPHY............................................................................................................................................13
Tables
Table1 Boundary Conditions.......................................................................................................................................5
Table 2 Measured and Modeled Site Groundwater Levels...........................................................................................7
Table 3 Mining Groundwater Level Table (Slurry Walls In-Place)................................................................................8
Table 3aMining Groundwater Level Table with Monarch DENM Site............................................................................9
Table 4 Base Model and Modeled Site Groundwater Level After Cell 3 Slurry Wall...................................................10
Table 5 Base Model and Modeled Site Groundwater Level After Cell 3,and 4 Slurry Walls......................................11
Table 6 Base Model and Modeled Site Groundwater Level After Full Buildout at Both Sites.....................................12
Groundwater Model Report—Section 20 Gravel Mine Site -ii- August 2022