PERMFILE59652

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: 1990 ALLUVIAL VALLEY FLOOR INVESTIGATIONS FOR THE YOAST MINE
• Section_Exhibit Name: TAB 16 ATTACHMENT 16-3
• Media Type: D
• Archive: No

• July 1993 -i- 923-2515
TABLE OF CONTENTS

1.0 INTRODUCTION ...................................... 1
1.1 Purpose ........................................... 1
1.2 Background ........................................ 1
1.3 Site Description ...................................... 2
1.4 Report Organization ................................... 2
2.0 GEOLOGIC FIELD INVESTIGATION PROGRAM ............ 3
2.1 Aerial Photograph Interpretation ............................ 3
2.2 Field Verification and Geologic Units ........................ 4
3.0 GEOLOGY OF THE DRAINAGES ......................... 6
3.1 Scotchman's Gulch .................................... 6
• 3.2 Armand Draw ....................................... 7
3.3 Unnamed Drainage 8
3.4 Grassy Creek ....................................... 9
3.5 Summary ..........................................11
4.0 ECOLOGICAL INVESTIGATION ......................... 12
4.1 Methods of Identification and Mapping ........................ 12
4.2 Description of Agricultural and Non-Agricultural Fields ............. 14
4.3 Alluvial Valley Floor Definition ............................ 14
5.0 RESULTS AND DISCUSSION OF THE ECOLOGICAL
INVESTIGATION ......................................16
5.1 Grassy Creek ....................................... I6
5.1.1 Streamtlow, Ground Water, and Water Quality ............. 16
5.1.2 Water Rights, Irrigation Ditches and Diversion Ponds ......... 18
5.1.3 Existing Flood Irrigation Areas ....................... 18
5.1.4 Subirrigated Areas .............................. 18
5.1.5 Potential Flood Irrigation .......................... 19
_ • 5.1.6 Wetlands .................................... 22
5.1.7 Native Rangeland . 23
5.1.8 Dryland Agriculture ............................. 24
Golder Associates