APPCOR11526

• Permit No: C1989074
• IBM Index Class Name: Application Correspondence
• Doc Date: 4/18/1989
• Doc Name: RIMROCK STRIP MINE APPLICATION ADEQUACY REVIEW PN C-89-074
• From: MLRD
• To: JIM STEVENS
• Media Type: D
• Archive: No

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STATE OF COLORADO
Roy Romer, Governor
~~
DEPARTMENT OF NATURAL RESOURCES
MINED LAND RECLAMATION DIVISION
FRED R. BANTA, Director
DATE: April 18, 1989
T0: Jim Stevens I n
FROM: Jim Pendleton =`"`""Y~~
RE: Rimrock S rip Mine lication - Adequacy Review
it #C-89-074)
In response to your request, I have completed a review of the geotechnical
aspects of the Rimrock Strip Mine permit application. In general, the
application is inadequate to clearly define the operator's intended mine
plan. I forward the following comments for your consideration in preparing
your adequacy opinion letter.
Operation Plan (Rule 2.05.3)
The operator's mine plan discussion is inadequate to comply with the
requirements of Rule 2.05.3(2)(a). The operator mentions an intention to
limit disturbance to 1.5 acre areas at any one time. However, no
explanation is presented to describe how this will be accomplished. In
general, the entire mine plan description is too vague to allow the
Division to formulate an opinion regarding the plan's technical merits.
2. The operator presents a brief discussion of its plan to remove overburden
above old shallow underground workings using a small dragline and "light
load" equipment to clean exposed coal. If the intention is to suggest
that surface equipment would operate above underground workings covered
by thin quantities of roof coal, the operator will need to elaborate on
this plan to demonstrate that such an activity is safe to the miners, and
feasible to conduct.
3. Apparently, the operator originally intended not to mine beneath the
Engleville Gulch, but later changed the mine plan. There is no specific
discussion of how they intend to divert the Engleville Gulch channel
flows around the 1.5 acre disturbance as it proceeds through Phase IA,
during which the channel portion of the gulch is to be mined. Topics,
such as the channel reconstruction and transition at the boundary of the
mined area will have to be addressed. They will also need to present a
detailed plan for recreation of a stable channel, capable of withstanding
the anticipated erosional forces. These will be critical considerations,
which should be carefully scrutinized by your surface water hydrologist.
215 Centennial Building, 1313 Sherman Street Denver, Colorado 80203-2273 Tel. [phone]