UNITED STATES
DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
District 9
ACCIDENT INVESTIGATION REPORT
UNDERGROUND COAL MINE
FATAL FALL OF ROOF ACCIDENT
Golden Eagle Mine [I.D. No. 05-02820]
Basin Resources, Inc.
Weston, Las Animas County, Colorado
October 25, 1995
By
Jeff Fleshman
Mining Engineer
Michael C. Stanton
Coal Mine Safety and Health Specialist
Originating Office: Mine Safety and Health Administration
P.O. Box 25367, Denver, Colorado 80225-0367
John A. Kuzar, District Manager
GENERAL INFORMATION
The Golden Eagle Mine is an underground coal mine, operated by
Basin Resources, Inc., a subsidiary of Entech Inc., which is a
subsidiary of Montana Power. The mine is located four miles west
of Weston, Colorado, on State Route 12. The mine has two
continuous mining machine development sections, and one
retreating longwall mining section. The headgates are developed
with three entries and the mains are developed with five to seven
entries.
The mine presently employs 181 underground miners and 50 surface
workers, and has a daily production of approximately 9,600 tons
of coal. The mine works three production shifts per day, six
days per week.
Coal is extracted from the development sections by remote
controlled Joy 12 CM continuous mining machines and is
transported from the face by a continuous belt-conveyor system
(Joy FTC flexible train conveyor) and by Joy 10 SC-22 shuttle
cars. Roof supports are installed utilizing Fletcher CDDR-13-B-
C-F and Eimco 3520-50 roof bolting machines. Retreat longwall
mining is performed with a remote controlled Joy 3LS shearing
machine in conjunction with Gullick Dobson 2-legged shields and
an American Longwall chain conveyor.
The mine liberates an average of 4,953,000 cubic feet of methane
in a 24-hour period, and is ventilated by three main mine fans as
follows:
- A blowing, Jeffrey axivane 2-stage main mine fan, model
8HUA96, producing 586,287 cfm, at 7.1-inches water gage,
- An exhausting TLT Babcock axivane single stage main mine
fan, model GAF24.34/10.6-1, producing 576,645 cfm, at 5.7-
inches water gage,
- An exhausting Jeffrey axivane single stage bleeder fan,
model 12A83, producing 83,156 cfm, at 6.4-inches water gage.
The principal mine officials are:
Jim Murphy............President
John Reynolds.......General Manager, and Principle Officer of Health and Safety
K. N. Hallows.......Safety Manager
The last Regular Safety and Health Inspection conducted by the
Mine Safety and Health Administration was completed on September
30, 1995.
DESCRIPTION OF ACCIDENT
On Wednesday, October 25, 1995, at 3:00 p.m, the 5-Left section
crew entered the mine under the supervision of Curtis Clark,
Section Foreman, and arrived on the 5-Left development section at
3:25 p.m. Clark examined the working section, held a safety
meeting, and reviewed work assignments with the crew. Mining
activities and coal production proceeded as normal.
Just prior to the accident, Murrell L. Browning, victim and left-
side roof bolt operator, and Frank Barron, right-side roof bolt
operator, were installing the second row of roof bolts in the
unsupported roof of entry No. 2, approximately 85-feet inby
crosscut No. 19. Browning had installed two bolts on the left
side, and Barron had installed the center bolt on the right side
of the row. During installation of Barron's center bolt, a
suction problem developed in the right-side drill head. Browning
traveled the walkway in the center of the machine to the right-
side to assist Barron. Browning stood between the pressurized
ATRS system and the right-side drill boom, with his back to the
unsupported area, and began cleaning a section of the partially
plugged suction hose. Barron traveled to the back of the machine
to de-energize electrical power. At approximately 5:45 p.m., a
fall of roof occurred in the unsupported area inby the ATRS
system. The roof rock pivoted such that it extended outby into
the supported area, crushing Browning against the right-side
drill boom.
At the time of the fall, Barron was standing at the back right-
side of the Fletcher roof bolting machine. Clark and Ben Garcia,
Eimco roof bolting machine operator, heard the noise from the
fall, and were the first persons to arrive at the accident scene.
Garcia started the roof bolting machine and moved the right-side
drill head to free Browning.
CPR was started as soon as Browning was placed on a stretcher,
and continued until arrival on the surface. Browning was then
taken by ambulance to Mt. San Rafael Hospital in Trinidad,
Colorado, where he was pronounced dead.
PHYSICAL FACTORS INVOLVED
- The accident occurred on October 25, 1995, at 5:45 p.m., in
the 5-Left development section, entry No. 2, approximately
85-feet inby crosscut No. 19.
- The 3-entry, 5-Left section was being developed with entries
on 115-foot centers, and crosscuts on 140-foot centers.
- Coal was being produced in the section using a continuous
mining machine in conjunction with a flexible train
conveyor.
- A Fletcher roof bolting machine, model No. CDDR-13-B-C-F, in
conjunction with a T-bar type ATRS system, rated at 38,250
pounds, was being used for installation of roof bolts for
primary roof support.
- The immediate roof throughout the 5-Left section was poorly
jointed, unconsolidated shale.
- No. 7 (7/8 inch diameter) rebar combination type roof bolts
were being installed throughout the section. Metal screen
was being used in conjunction with the roof bolts in all
entries in the 5-Left section. Roof support was being
installed in accordance with the roof control plan approved
on August 8, 1991, with revisions dated October 20, 1994,
and May 17, 1995.
- Before the fall occurred, seven combination type roof bolts,
84-inches in length, had been installed in the bolting
cycle. Four bolts were installed in the first row and three
bolts were installed from left to right in the second row.
- The mining height at the accident scene was approximately 8
to 8.5 feet and the entry width was approximately 18 feet.
- Browning was standing under supported roof, with his back to
the unsupported area, between the pressurized ATRS system
and the right-side drill boom, cleaning a section of
partially plugged suction hose.
- The inby unsupported mine roof fell in such a way that it
pivoted and extended under the ATRS system, crushing the
victim against the right-side drill boom.
- The rock that struck Browning was approximately 12 to 15
feet wide, 4 feet long, and 7 to 10 inches thick. It was
part of a roof fall that measured approximately 12 to 15
feet wide, 12 to 14 feet long, and 4 to 30 inches thick.
Normal mining practice involved full seam extraction,
including 6 to 24 inches of cap rock. The cap rock was
mined to prevent it from falling prior to bolting.
Approximately 18 inches of cap rock had been mined in the
unsupported area.
- Browning received 40 hours of new miner training according
to 30 CFR 48.5, which was completed on November 10, 1994.
This training was given due to Browningūs past unemployment
and the uncertainty as to his mining experience in the last
3 years. Browning also received roof bolting task training
on February 3, 1995, and annual refresher training on April
10, 1995.
- Barron stated that Browning had visually examined and scaled
the roof before traveling to the right-side of the machine
to assist with the partially plugged suction hose.
CONCLUSION
The accident occurred due to undetected abnormalities in the
unsupported roof which resulted in a fall of roof inby the
pressurized ATRS system. A contributing factor was managementūs
failure to require the roof bolting machine to be moved away from
the unsupported area while repairs were being made.
VIOLATIONS
The investigation did not reveal any violations of Title 30 Code
of Federal Regulations that contributed to the cause of the
accident.
A Section 103(k) Order, No. 4057724, dated October 25, 1995, was
issued following the accident to ensure the safety of the miners.
Respectfully submitted by:
Jeff Fleshman
Mining Engineer
Michael C. Stanton
Coal Mine Safety and Health Specialist
Approved by:
John A. Kuzar
District Manager
Related Fatal Alert Bulletin: [FAB95C37]
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