GENERAL49320

• Permit No: M1999002
• IBM Index Class Name: General Documents
• Doc Date: 7/22/1999
• Doc Name: FINAL ENVIRONMENTAL IMPACT STATEMENT VOLUME 2
• Media Type: D
• Archive: No

April 15, /999 Pagc i
• SUBSIDENCE MONITORING PLAN
Submitted by
AMERICAN SODA, L.L.P
for
YANKEE GULCH SODIUM MINERALS PROJECT
Table of Contents
Pa e
1.0 IIVTRODUCTION ......................................................1
2.0 SURFACE SUBSIDENCE MONITORING ................................. 1
2.1 Monument Locations for the Initial Mining Area ......................... 1
2.2 Monument Locations for Future Mining Areas ........................... 1
2.3 Surface Monitoring Frequency and Duration ............................. 2
3.0 SUBSURFACE MONITORING .......................................... 2
3.1 Time Domain Reflectometry ............................. ............ 2
3.2 Borehole Geophysics ................................... ............3
3.3
3.4 Solution Cavity Characterization ..........................
Subsurface Monitoring Frequency and Duration .............. ............ 3
............ 3
4.0 REPORTING ..........................................................4
5.0 MITIGATION .........................................................4
6.0 QUALITY ASSURANCE AND QUALITY CONTROL ....................... 4
7.0 REFERENCES ......................................................... 5
List of Fit=_ures
P~
Figure 1. Subsidence Monitoring Plan for Yankee Gulch Lease ..................... 6
Figure 2. Schematic of Typical Well Completion with TDR Installation and
Monitoring and Instrumentation String .............................:... 7

Agapito Associates, Inc.