Independent Review of MSHA's Actions at Crandall Canyon Mine

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offset between crosscuts 139 and 142 in the retreat mining sequence in the South Barrier. Although Owens required the pillars to be skipped to better protect the bleeder entry and weekly examiner, which was a valid concern, the potential impacts of skipping pillars was not properly evaluated, nor were alternatives explored. For instance, the entire issue of skipping pillars around the sump offset area could have been completely avoided by requiring that retreat mining begin outby crosscut 139. Yet another inconsistency between the consultant’s report and the approved roof control plan concerned slabbing, or mining into, the barrier to the south of the South Barrier entries. The April 2007 AAI report discusses how the wider span created by slabbing 40 feet of the barrier is, “expected to improve caving conditions compared to the north and reduced concentrated loads at the face.” Despite this and other statements such as “slabbing the south-side barrier is expected to benefit caving,” the roof control plan allowed no slabbing from crosscut 139 to 142. Again, if the consultant report is used to justify the plan approval, recommendations that contradict the consultant should be thoroughly evaluated for any potential negative impact. Such an evaluation was not conducted by the District. The March 10 th bounce in the North Barrier section, and the subsequent AAI report also led to an additional instance where the District failed to adequately evaluate data submitted by the mine operator. One of the primary recommendations made by AAI to protect against “problematic bumping” in the South Barrier section was to increase the length of the pillars. The report stated that, “The added 37 foot length, approximately equivalent to an extra cut, increases the size and strength of the pillars’ confined cores, which helps to isolate bumps to the face and reduce the risk of larger bumps overrunning crews in outby locations.” This contradicts the July 20, 2006, AAI report that asserted, “model results indicate that increasing crosscut spacing does not significantly improve conditions.” District 9 did not question these conflicting statements. Rather, the District accepted the April 18, 2007, AAI report at face value without questioning conflicting statements or verifying the updated modeling. The approved roof control plan also did not reflect the mining height used as an input parameter by the consultant in both the ARMPS and LAMODEL analyses. These models, and the District’s own ARMPS evaluation, limited the mined height input to eight feet. Since both ARMPS and LAMODEL are extremely sensitive to changes in mined height, this should have been recognized and reflected in the roof control plan. The stratigraphic column included in the roof control plan depicts the Hiawatha coal seam as 4-to-10 feet in thickness. Thus, it would be reasonable to assume that the seam would allow development mining that could have exceeded eight feet, but this was not prohibited by the plan. An increase in mining height above eight feet would result in a reduction in pillar stability factors. 26
Conclusion: The consultant’s recommendations that were included in reports submitted by the mine operator to support pillar extraction in the South Barrier section were not consistently included in the approved roof control plan. When the roof control plan contradicted the consultant’s recommendations, a thorough analysis of the potential consequences was not conducted. The District also failed to recognize the importance of mined height in the analysis of stability factors and bump potential of pillars. Plan approval was reportedly based in part on computer modeling which was conducted with an eight-foot mining height, but this was not accounted for in the roof control plan. Recommendation: Consultant recommendations used to support mine plan submittals should be specifically addressed in such plan approvals. When plan approval is based on computer modeling, model input parameters should be specifically reflected in the plan. 6) The adequacy of the required six-month plan reviews. District 9 had a formal SOP for the review and approval of roof control plans. Specialists, including the roof control supervisor, reviewed all new plans and supplements. Historically, the specialists assigned to the district office would also conduct the mandatory six-month plan reviews required by § 75.223(d). Due to attrition and other work assignments, these duties had been assumed and conducted by mine inspectors in District 9 since early 2006. These reviews were documented by completion of the MSHA 2000-204 Plan Review forms, which were submitted with the required quarterly inspection reports. While the use of the 2000-204 forms as a means of documenting the six-month plan reviews is in itself not a deficiency, the IRT found an issue that impacted the adequacy of this practice in District 9. The inspectors in the Price Field Office stated that when they documented a plan deficiency on the MSHA 2000-204 form, they seldom received any feedback from the District personnel responsible for that plan area. Inspectors stated that this lack of communication with the District Office concerning plan inadequacies cited via the 2000-204 form was not an isolated instance, but rather an ongoing practice that had existed for some time. The District 9 Roof Control Branch SOP required the plan reviewer do the following: • Review comments from the roof control specialist or supervisor; • Review plan review forms and previous roof control citations issued since the last plan review; and • If comments from the field personnel will not be incorporated, notify that person(s) of your reasoning for not incorporating the comments. 27
Page 1: Independent Review of MSHA’s Acti
Page 4 and 5: Protective Ground Support Used Duri
Page 7: Location of March Bounce Last Known
Page 10 and 11: EXECUTIVE SUMMARY The Federal Mine
Page 12 and 13: • Persons who could have contribu
Page 14 and 15: There was no lack of hard work and
Page 16 and 17: BLM INSPECTIONS OF CRANDALL CANYON
Page 18 and 19: oxygen and dust into the fresh air
Page 20 and 21: MSHA’S ACTIONS PRIOR TO AUGUST 6,
Page 22 and 23: that the proposed retreat sequence
Page 24 and 25: On February 23, 2007, District 9 re
Page 26 and 27: technical guidance from someone exp
Page 28 and 29: District management’s oversight w
Page 30 and 31: elieved that a higher stability fac
Page 32 and 33: questions were asked in an attempt
Page 36 and 37: To determine the validity of the in
Page 38 and 39: disapproval to the District Manager
Page 40 and 41: amendments for the South Barrier re
Page 42 and 43: The following table contains certai
Page 44 and 45: The Price Field Office did not inve
Page 46 and 47: The inspector stated that this even
Page 48 and 49: conducted every seven days. However
Page 50 and 51: Recommendation: MSHA should establi
Page 52 and 53: DIRECTION AND ACTIVITIES DURING THE
Page 54 and 55: 111-8, which was in effect at the t
Page 56 and 57: MSHA Person-In-Charge of Mine Rescu
Page 58 and 59: Davis stated that when Stickler and
Page 60 and 61: There was also no verification that
Page 62 and 63: employee stated, “Everybody got f
Page 64 and 65: Underground Phone Communication Sys
Page 66 and 67: PROTECTIVE GROUND SUPPORT USED DURI
Page 68 and 69: equipment to tram in and out of the
Page 70 and 71: Top of Rockprop Bottom of Rockprop
Page 72 and 73: Canyon the inby end of the ropes wa
Page 74 and 75: educed to writing and served to the
Page 76 and 77: planned to film the underground res
Page 78 and 79: Stickler stated that family members
Page 80 and 81: Conclusion: MSHA failed to enforce
Page 82 and 83: Later on August 6 th , a mine rescu
Page 84 and 85:
anybody sit down with the MSHA peop
Page 86 and 87:
EXPLORATIONS During the underground
Page 88 and 89:
since the ribs could not further ex
Page 90 and 91:
DRILLING OF BOREHOLES Boreholes pla
Page 92 and 93:
pump for a period of time, the meas
Page 94 and 95:
After this hole was drilled, MSHA
Page 96 and 97:
The borehole showed there was no vo
Page 98 and 99:
RISK VERSUS VALUE In all rescue and
Page 100 and 101:
stoppings to crosscut 95 would also
Page 102 and 103:
section were equipped with Self-Con
Page 104 and 105:
data, the idea was not pursued any
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for an hour and one-half and then w
Page 108 and 109:
sampling equipment to their truck a
Page 110 and 111:
Agency. The handbook consisted of 9
Page 112 and 113:
updates and briefings on the rescue
Page 114 and 115:
Utah Governor Jon Huntsman, Jr., MS
Page 116 and 117:
Stickler contradicting or correctin
Page 118 and 119:
trapped miners should, to the exten
Page 120 and 121:
Conclusion: The MSHA person-in-char
Page 122 and 123:
An attachment to the policy sets fo
Page 124 and 125:
air and water waiting for us to com
Page 126 and 127:
Davis did clarify that there was no
Page 128 and 129:
the family and press briefings, and
Page 130 and 131:
emergency with role-playing by all
Page 132 and 133:
MINER ACT AND MINE EMERGENCY EVACUA
Page 134 and 135:
Post-Accident Communications The MI
Page 136 and 137:
Recommendation: The Agency should d
Page 138 and 139:
At the time of the accident, the ER
Page 140 and 141:
locations, and along normal travel
Page 142 and 143:
CMS&H STAFFING AND RESOURCE UTILIZA
Page 144 and 145:
CMS&H STAFFING LEVELS District staf
Page 146 and 147:
In addition to the decreased levels
Page 148 and 149:
completion rate decreased dramatica
Page 150 and 151:
Other specialists had limited inspe
Page 152 and 153:
ALLEGATIONS OF INFLUENCE BY THE MIN
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GENERAL CONCLUSION Internal Reviews
Page 157:
APPENDIX A LIST OF PERSONS INTERVIE
Page 160 and 161:
Moore, III, Clarence W. ...........
Page 163:
List of Ground Control Panel Member
Page 167:
Event Number Activity Code Genwal R
Page 171 and 172:
Borehole #3 Location: #4 Entry, X-c
Page 174 and 175:
Oxygen Content of Air: Sign and Sym
Page 177 and 178:
EFFECTIVE DATE: 12/22/2006 EXPIRATI
Page 179 and 180:
Act, Pub. L. No. 109-236, June 15,
Page 183:
APPENDIX G PROGRAM POLICY LETTER NO
Page 186 and 187:
2006. The MINER Act requires that t
Page 188 and 189:
The above table is based on the 199
Page 190 and 191:
2. Inflatable shelters or equivalen
Page 193:
APPENDIX H PROGRAM INSTRUCTION BULL
Page 196 and 197:
I. Quantity of Breathable Air. In d
Page 198 and 199:
What is MSHA's authority for this P
Page 201:
NORTH BARRIER Last Known Location o
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Independent Review of MSHA's Actions at Crandall Canyon Mine

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