2008-06-16_REVISION - M2000098

• Permit No: M2000098
• IBM Index Class Name: REVISION
• Doc Date: 6/16/2008
• Doc Name: Review of West Sediment Pond Design
• From: DRMS
• To: Colorado Lime Company
• Type & Sequence: TR1
• Email Name: ACS
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203 C O L O R A D O
[

Phone: [phone] DIVIS I O N OF

RECLAMATION
FAX: [phone] MINING
June 16, 2008 ? SAFETY
Mr. Tracy Gunn
?G 'J Bill Ritter, Jr.
Governor
Colorado Lime Company
1468 Highway 50 Harris D. Sherman

Delta, CO 81416 Executive Director
/
t/ Ronald W. Cattany

RE: Review of West Sediment Pond Design, Monarch Quarry, Division Director
Natural Resource Trustee
Technical Revision TR-01, Permit No. M-2000-098

Dear Mr. Gunn:
The Division of Reclamation, Mining, and Safety (DRMS) has reviewed the designs for the open channel spillway to be
installed in the west sediment pond at the Monarch Quarry. Those designs are based on passage through the spillway of
the peak flows resulting from a 5 year, 24 hour rain event at the quarry, the same design storm that the pond was
constructed to contain. The Colorado State Engineer's dam safety regulations require that the spillway for ponds such as
the west sediment pond (minor dam, no potential hazard) be designed to pass peak flows from the 25 year, 24 hour
event. This will require widening of the spillway to a bottom width of 10 feet (see enclosed calculations) or increasing
the depth of the spillway. However, if you chose to increase spillway depth, that design change must be reconciled with
the resultant decrease in storage for the 5 year event inflow. Please provide revised design documents for the spillway.
Please provide a detailed description of the determination that the contributing drainage area to the west sediment pond
is 125 acres and address whether or not the increased design requirement discussed above would result in any change to
the contributing basin configuration. For example, if the contributing basin was determined considering the presence of
upgradient ditches and berms, and those ditches and berms could be breached during the 25 year event, then the designs
must be revisited through evaluation of the thus enlarged contributing basin.
The State Engineer requires that storm water detained in ponds such as the west sediment pond either soak into the
ground or be released to the natural drainage system within 72 hours. Please describe how Colorado Lime will comply
with this water rights requirement.
I sent you an email last Friday, June 13, 2008 discussing the need for an extension to the decision date for technical
revision TR-01, which was June 15, 2008. Please provide a written extension request prior to June 25, 2008 or the
DRMS will have to deny the technical revision in accordance with Rule 1.9 of the Construction Materials Rules of the
Colorado Mined Land Reclamation Board.
If you have any questions, please contact me at 303-8664063 or at allen.sorenson(a)state.co.us.
Since ry,
Allen C. Sorenson
Reclamation Specialist S C N
enclosure(s)
c:\acs files\My Documents 4-19-06\monarch trl review.doc
Office of Office of
Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines