GENERAL31435

• Permit No: C1989074
• IBM Index Class Name: General Documents
• Doc Date: 12/14/1993
• Doc Name: Proposed Decision & Findings of Compliance for SL1
• From: Phase I
• Permit Index Doc Type: Findings
• Media Type: D
• Archive: No

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Findings of the
Division of Minerals and Geology
for the
Rimrock Strip Mine, Permit No. C-89-074
Phase I Bond Release Application
I
II
Procedures for Seeking Release of Performance Bond (Rule 3.03.2)
The Division finds that., based on the review process history, the requirements
for seeking release of performance bonds as set forth in Rule 3.03.2 have been
met. Copies of written notices as required by Rule 3.03.2(1)(a> have been
submitted to the Division. Proof of publication in accordance with
Rule 3.03.2(10)(b> has also been submitted. The current landowner,
Mrs. Gloria Davis, was notified of the bond release inspection. A site
inspection was held in accordance with Rule 3.03.2(2).
Criteria and Schedule for Release of Performance Bonds (Rule 3.03.1)
Phase I - Rule 3.03.1(2)(a) states, "Up to sixty percent of the applicable bond
amount shall be released when the permittee successfully completes backfilling,
regrading, and drainage control in accordance with the approved reclamation
plan".
The operator has supplied a certified map, Exhibit KK, final Topography of
Permit Area that shows that the disturbed areas a~ETie pit have been backfilled
and regraded in accordance with the approved reclamation plan. The approved
plan calls for reclaimed slopes to be no steeper than 4H:1V. Field
investigations by the Division have verified that reclaimed slope gradients for
the pit area range from 4.7H:l.OV to 6.3H:l.OV with the average of the slope
gradients being 5.4H:1.OV. The regraded slopes have not exhibited any evidence
of geotechnical instability. The topsoil stockpile area has been regraded and
covered with mulch. The oil tank containment area remains unreciaimed as of the
site inspection by Division personnel on December 13, 1993. A small subsidence
depression also remains unreciaimed on the east side of the permit area. This
subsidence pit is approximately 8 feet deep and 20 feet in diameter, and has
resulted from pre-law underground mining operations that occurred previous to
the issuance of this permit. This subsidence feature is located within the area
originally scheduled to be disturbed during the second phase of the mining
operation plan. Mining operations never advanced beyond the first phase, as
such, this subsidence feature lies beyond the area actually disturbed by Rimrock
Coal Company operations.
The permit calls for reclamation of all subsidence features within 250 feet of
the pit boundary. The Division therefore finds that with the exception of the
oil tank containment area and the pre-permit subsidence feature, the operator
has backfilled all required disturbed areas, to ensure stability and to
eliminate all spoil piles, highwalls, and depressions in accordance with
Rule 4.14.1(2). Backfilled material has been placed to minimize adverse effects
on ground water as required by Rule 4.14.1(2)(b>. The Division also finds that
the regraded areas, with the exception of the oil tank containment area and
pre-permit subsidence feature, meet the approximate original contour
requirements of Rules 4.14.1(2>(a) and 4.14.2(1).