2018-06-20_REVISION - M1977300

• Permit No: M1977300
• IBM Index Class Name: Revision
• Doc Date: 6/20/2018
• Doc Name: Adequacy Review Response
• From: Colorado Legacy Land, LLC
• To: DRMS
• Type & Sequence: TR26
• Email Name: MAC
• Media Type: D
• Archive: No

Cotter Corporation Schwartzwalder Mine

RML CO-369-06
Cotter Corporation (N.S.L.) i March 2017

TABLE OF CONTENTS

1.0 INTRODUCTION ................................................................................................. 1
1.1 LOCATION ............................................................................................................ 2
1.2 FACILITY DESCRIPTION ......................................................................................... 2
1.2.1 New Water Treatment Plant (NWTP) – Current Facility .............................. 2
1.2.2 Old Water Treatment Plant (OWTP) – Current Facility ............................... 2
1.2.3 Ore Transfer Pad – Decommissioned ........................................................... 3
1.2.4 Ore Crusher-Sorter – Decommissioned ........................................................ 3
1.2.5 Drying Trenches........................................................................................... 3
1.3 PREVIOUS DECOMMISSIONING HISTORY ................................................................ 4
1.3.1 Ore Transfer Pad Decommissioning ............................................................. 4
1.3.2 Ore Crusher-Sorter and Old Ponds Decommissioning ................................. 4
1.3.3 Drying Trench Decommissioning ................................................................. 5
1.3.4 Wastewater Treatment Plant Decommissioning ............................................ 5
1.4 SCOPE .................................................................................................................. 6
2.0 CURRENT CONDITIONS ................................................................................... 7
2.1 CONSTITUENTS OF CONCERN ................................................................................ 7
2.2 HISTORICAL CLEANUP LEVELS .............................................................................. 8
2.3 BACKGROUND CHARACTERISTICS ......................................................................... 8
2.3.1 Direct Gamma Exposure Monitoring............................................................ 8
2.3.2 Soil Background Assessment ........................................................................ 8
2.4 GAMMA WALKOVER SURVEY ............................................................................... 9
2.5 SCOPING SURVEY ................................................................................................. 9
2.5.1 Structures ..................................................................................................... 9
2.5.2 Soils ........................................................................................................... 10
3.0 CRITERIA FOR LICENSE TERMINATION .................................................. 12
3.1 STRUCTURES AND EQUIPMENT ............................................................................ 12
3.1.1 Preliminary Scoping................................................................................... 12
3.1.2 NWTP Contamination Surveys ................................................................... 12
3.2 SOILS ................................................................................................................. 13
4.0 DECOMMISSIONING ACTIVITIES ................................................................ 16
4.1 ORGANIZATIONAL PERSONNEL............................................................................ 16
4.2 DECOMMISSIONING OBJECTIVES AND APPROACH ................................................ 16
4.2.1 Decommissioning Objectives ...................................................................... 16
4.2.2 Decommissioning Approaches.................................................................... 17
4.3 SITE PREPARATION ACTIVITIES ........................................................................... 17
4.4 DECOMMISSIONING PROCEDURES ........................................................................ 19
4.4.2 Sequence of Barrens Ponds Demolition ...................................................... 19
4.4.3 Sequence of Soils Remediation ................................................................... 20
4.5 MATERIAL DISPOSAL .......................................................................................... 20
4.6 POST DEMOLITION ACTIVITIES ............................................................................ 21