GENERAL32524

• Permit No: M1978116
• IBM Index Class Name: General Documents
• Doc Date: 9/25/2006
• Doc Name: Lysimeter Installation and Monitoring Plan Review and Approval
• From: DRMS grm
• To: Cotter Corporation
• Permit Index Doc Type: General Correspondence
• Media Type: D
• Archive: No

STATE OF COLORADO
- DIVISION OF RECLAMATION, MINING AND SAFETY
C,R~/cd~ /~~P/,Qca
Department of Natural Resources
1313 Sherman SL, Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
September 25, 2006'/
C O L D AA D O
D I V I S I O N O F
RECLAMATION
MINING
-&-
C^C r~ SAFETY
RC6~C~~l~p Bill Owens
Governor
SEP ~ ~ ~l)Vb Russell George
~+ Executive Director
I~IYISIOn Ot ndUafilatl0n, Ronald W. Cattany
Glen Williams / Mining and Safety Division Director
Cotter COrpOratlOn Natural Resource Trustee
P.O. BOX 700
Nucla, Colorado 81424
Re: SM-18 Mine, M-1978-II6, Lysimeter Installation and Monitoring Plan Review and Approval.
Dear Mr. Williams:
The Division of Reclamation, Mining and Safety has reviewed the plan Cotter submitted for installation
of a lysimeter well at the SM-18 Mine down gradient from existing waste dumps. The purpose of the
well is to collect data for review on the possible migration ofgeo-chemical constituents identified in
waste rock into the underlying bedrock.
Primarily the well will determine if there is any localized groundwater directly below and down gradient
from the dump that would create a path for the identified constituents to reach waters that could
potential create a condition that is harmful to human health and the environment. The well and
monitoring may provide empirical data to support modeling presented in Cotter's appeal of DMO status
determination by the Division. The secondary use of the well will be an early detection system for any
potential migration of the identified geo-chemical constituents in the future.
The placement of the well is in a location that Division staff and Cotter agreed upon during the May
2006 t5eld visit. The constnlction diagrams for the wel[ were presented with maps in a "Supplemental
Geology Report" submitted to the Division on August 10`h, 2006. The Division is approvint; the
location and construction of the well as submitted. The Division will require a copy of the drill logs and
construction notes within 10 working days of final construction of the well.
Cotter has proposed a monitoring schedule of monthly sampling to establish a baseline set of data. The
Division feels that a more aggressive monitoring plan for the first 3 months is in order and gradual
scaling back of frequency if no detections are observed. The preferred schedule is once every 2 weeks
for the firsC 3 months provided no moisture is detected. If moisture is detected, the Division must be
notified within lOworking days in writing and the sampling frequency maybe modified dependin; on
volumes and other parameters. Any water samples collected from the lysimeter are to be tested for
constituents per groundwater standards. Once the 3 month period has been completed, a review of data
will be used to determine future sampling intervals. Tfno moisture is detected during the first sampling
interval, the schedule may be reduced to quarterly for the next 4 quarters and possibly further after that
review. All sampling reports are to be submitted to the Division in writing within 10 working days of
either the actual sampling date or receipt of laboratory results from that sampling period.
Oftice of Office of
Mined Land Reclamation Active and Inactive Mines