2014-05-29_HYDROLOGY - M1977342

• Permit No: M1977342
• IBM Index Class Name: Hydrology
• Doc Date: 5/29/2014
• Doc Name: 5-Quarter Water Quality Data and Baseline Parameters Report
• From: Climax
• To: DRMS
• Permit Index Doc Type: Hydrology Report
• Email Name: PSH
• Media Type: D
• Archive: No

' CMC—Henderson Operations
5-Quarter Water Quality Data and Baseline Parameters Report
May 2014
Table of Contents
1.0 Introduction and Background ..............................................................................................2
2.0 Groundwater Studies............................................................................................................2
3.0 Baseline Parameters and NPL Assessments........................................................................2
' 3.1 MLGW-ACR....................................................................................................................2
3.1.1 Monitoring Summary................................................................................................2
3.1.2 Baseline Parameters Data Assessment...................................................................... 3
' 3.1.3 NPL Assessment....................................................................................................... 3
3.2 MLGW-15........................................................................................................................4
3.2.1 Monitoring Summary................................................................................................4
' 3.2.2 Baseline Parameters Data Assessment::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::4
3.2.3 NPL Assessment........................... 5
3.3 MLGW-17............................................ ......... ......... ......... ......... ......... ................. .. 5
3.3.1 Monitoring Summary................................................................................................ 5
' 3.3.2 Baseline Parameters Data Assessment...................................................................... 6
3.3.3 NPL Assessment....................................................................................................... 6
3.4 Establishment of Ambient pH NPLs at Mill POCs.......................................................... 7
' 4.0 Monitoring Frequencies.......................................................................................................7
5.0 Conclusion........................................................................................................................... 8
Figures
Figure 1 MLGW-ACR Iron and Manganese
Figure 2 MLGW-15 and MLGW-17 pH Values
Tables
Table A MLGW-ACR Monitoring Data
Table B MLGW-15 Monitoring Data
Table C MLGW-17 Monitoring Data
Appendices
Appendix A Groundwater Monitoring Point of Compliance (POC) Update Memorandum
Appendix B Colorado Water Quality Control Commission Basic Standards for Groundwater,
Tables 1-4
Appendix C Establishing Background Threshold Values (BTV) - Henderson Mill
Page 1 of 9