DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
District 2
ACCIDENT INVESTIGATION REPORT
SURFACE OF UNDERGROUND MINE
FATAL POWERED HAULAGE ACCIDENT
Mathies (I.D. No. 36 00963)
Mon-View Mining Company
Courtney, Washington County, Pennsylvania
June 17, 1995
By
Joseph R. O'Donnell Jr.
Coal Mine Safety and Health Inspector
and
Marshall J. Brighenti
Coal Mine Safety and Health Inspector
Originating Office-Mine Safety and Health Administration
New Stanton District Office
RR 1, Box 736, Hunker, Pennsylvania 15639
Joseph J. Garcia, District Manager
GENERAL INFORMATION
The Mathies mine is operated by Mon-View Mining Company, and is located in Courtney, Washington County, Pennsylvania. Access into the mine is accomplished by two shafts and one drift opening into the Pittsburgh coal seam, which averages sixty-six inches in thickness. Employment is provided for 134 workers underground and 49 on the surface. The mine produces coal three shifts per day, five days per week.
Three developing continuous-mining-machine sections produce an average of 2,500 tons of coal daily. The coal is transported from the face by shuttle cars and discharged onto belt conveyors. A series of belt conveyors transport the coal to the underground North Mains Tipple where it is loaded into 15-ton mine cars. Trips of up to 40 mine cars are then towed by 50-ton track locomotives approximately 3 miles to the No. 1 surface rotary dump. The coal is dumped and then conveyed by belt to the preparation plant. Clean coal is loaded onto river barges and delivered to various customers.
The principal officers of the operation are as follows:
-
Joseph P. Valentine . . . . . . . . . . . . . . President
Brandon Baker . . . . . . . . . . . . . . . . . Vice President
The last Mine Safety and Health Administration regular Safety and Health Inspection, at this mine, was completed June 7, 1995.
DESCRIPTION OF ACCIDENT
On Saturday, June 17, 1995, the preparation plant crew arrived for the start of the 3:15 p.m. shift. Levi Hutchinson, plant foreman, issued work assignments for the day. Charles Colbert, rotary dump operator was assigned his normal job of dumping loaded mine cars at the No. 1 rotary dump. The preparation plant was not operating and the coal was being conveyed from the dump area to the plant where it was being stockpiled. The operator planned to process the coal on Monday, June 19, 1995.
Joe Vilchek, plant operator, spoke by plant pager phone with Colbert several times during the shift as he dumped each coal trip that came out of the mine before 9:30 p.m. Colbert and Hutchinson waited together in Hutchinson's office for the next trip. A loaded trip of 24 cars arrived on the surface at approximately 9:30 p.m., and Colbert began dumping procedures. The shift was scheduled to end at 10:30 p.m. Through interviews, it was determined Colbert intended to dump the trip of 24 coal cars by the end of the shift. Hutchinson overheard Colbert conversing by plant phone with Vilchek at 10:05 p.m. Colbert said he was assisting Bill Hess, motorman. The dump operator, as part of his normal duties, assists the motorman by uncoupling cars. Hess then took 20 empty coal cars back into the mine. At 10:10 p.m., Vilchek noticed that there was no coal on the preparation plant raw coal conveyor belt. He then called by plant phone to Colbert but there was no response. Another call was made at 10:12 p.m. to check if there was a possible problem with a car, he received no response. After hearing no response to Vilchek's calls, Hutchinson walked from his office to the rotary dump to investigate. Arriving at 10:15 p.m., he found the victim caught between the frame of the rotary dump and a loaded coal car. Hutchinson checked for a pulse but found none. Don Hlatky, guard, called Tri-Community Ambulance. The victim remained as found until the ambulance arrived at 10:40 p.m. No vital signs were detected by the ambulance crew. Tim Kegel, Deputy Coroner, Washington County, arrived at 11:00 p.m. The victim was pronounced dead at 11:05 p.m. The body was recovered and transported to Washington Hospital, Pennsylvania, where an autopsy was performed. The cause of death was listed as asphyxiation due to mechanical compression of the neck and trunk.
PHYSICAL FACTORS INVOLVED
The investigation revealed the following factors relevant to the occurrence of the accident:
- There are three separate communication systems located in the
rotary dump operator workstation. The plant pager phone provides
communication to all surface areas. This system is separate and
not connected to the underground phones. The trolley phone is used
to communicate with motormen underground and other equipment
provided with trolley phones. A mine pager phone is also utilized
for communication to working sections and other workstations
connected to the surface.
- Coal is mined in the working sections, transferred to North
Mains Tipple by conveyor belt, where it is loaded into 15-ton
capacity mine cars. Trips of up to 40 mine cars are towed by
50-ton track locomotives approximately 3 miles to the surface
rotary dump. The loaded mine cars are rotated 360 degrees at the
dump and the coal is dumped into the pit where it is transported
to the preparation plant via conveyor belt.
- Electric power for the mine originates at the Courtney Tipple
Substation which is maintained by West Penn Power Company. The
incoming power is 25 KV and is stepped down to 480 volts, 3 phase,
60 cycle. This power is transmitted to the rotary dump switchroom,
where it feeds the main switch. From the main switch, power is
distributed to the car haul and rotary dump. Electric controls for
the car haul and rotary dump are located in the dump operator room.
- A Belt Link rotary dump is used to dump the 15-ton capacity
mine cars. The rotary dump is enclosed in a housing and vented to
the outside. Illumination in the area appeared adequate. The
rotary dump was placed into service in 1947. The unit was
overhauled in 1968 and 1981. The overhaul consisted of replacing
metal structure that had deteriorated or where excessive wear was
evident.
- A retarder system was fabricated on site in 1981. The system
consists of a conventional truck air brake shoe drum assembly. A
drum wheel assembly was placed in a horizontal position with one
drum and dual wheels located on each side of the track. The tires
contact the sides of the cars and when the retarder is activated,
causes drag on the trip that prevents drifting during the dump
cycle. The air controlled retarder system is located on the empty
side of the rotary dump. The system also minimizes tension on the
couplers allowing them to move more freely during the dump cycle,
thus reducing the likelihood of uncoupling.
- The left retarder assembly on the empty side of the dump was
inoperative. The clevis and pushrod which activate the air chamber
were damaged. There was only one tire on the left wheel and it was
deflated. With the retarder system not functioning properly, less
pressure was placed on the couplers between the loaded and empty
cars.
- The rotary dump operator controls are located 12.5 feet from
the dump. The rotary dump measures 25 feet 7 inches in length and
7 feet 8 inches in width and is located in a building where it is
protected from the elements. A walkway is located 87 inches from
the dump and is 34 inches wide. Signs warning persons not to enter
are posted on a gate that access the walkway. The gate was found
open.
- A chain-driven 480-volt 3-phase electrically-powered car haul
is used to position loaded mine cars on the dump. Dawgs or latches
on the car haul are positioned in the center of the track. The
latches contact pockets under the car and facilitate car movement.
The loaded track is on a down grade of approximately 0.5 percent
toward the dump.
- Controls to operate the rotary dump and car haul are located in
a control room within 20 feet of either. Mine cars are moved
through the dump area using a single forward and reverse
electrically activated manual controller. Activation is
accomplished by depressing a foot switch that requires constant
pressure by the operator to move the cars. The car haul is not
equipped with a brake system that would hold a mine car when power
is removed or pressure is released from the foot switch. The
control for the car haul was found in the "reverse" position.
- The air activated retarder system is controlled by a single
manual hand controlled lever located in the dump operator's control
room. This control can be set and then locked in position to
remain on during the dumping operation. The retarder control lever
was found in the "on" position after the accident.
- An orange colored locator pin is positioned outside of the
control room for the rotary dump operator to use as a reference
point while positioning cars on the dump.
- Mine cars used throughout the mine measure 25 feet 3 inches in
length and 7 feet in width. Car Nos. 459 and 310 were both
damaged. The sides of the these mine cars were bent inward and
would not effectively contact the tires of the functioning right
retarder.
- Willison type automatic couplers are provided on all mine
cars. Car couplers are designed to facilitate dumping. A rotating
shank is provided on the automatic coupler installed on the inby
end of the car while the automatic coupler attached to the outby
end of the car is installed to prevent this end from turning. The
automatic coupler, inby end of mine car No. 310 and had apparent
signs of wear, the diameter of the shank was reduced significantly.
The car frame where the coupler shank contacts it was also worn,
which increased the amount of slack between both couplers
contributing to uncoupling of loaded mine cars while dumping.
- During the investigation, interviews with rotary dump
operators revealed that loaded cars uncoupled regularly during the
dump cycle. The frequency of uncoupling was at least two to three
times per week, per operator, prior to the accident.
- A simulation of the car haul procedure conducted during the investigation revealed that the car haul would not hold the cars in a stationary position with the controls left on. The loaded mine cars drifted towards the rotary dump. The average time to dump a loaded coal car was approximately one minute. Car No. 21 was loaded and scheduled to be dumped prior to the accident and coupled to mine car No. 310. Car Nos. 310 and 459 along with three other empty cars were the last cars dumped by the victim. Failure of the retarder system and uncoupling of car No. 310 caused these five cars to drift down the empty track.
CONCLUSION
The accident occurred when the dump operator entered the rotary dump to align the coupler of car No. 310 which had just been dumped. The remaining 19 loaded coal cars drifted down grade and pinned the victim between the frame of the rotary dump and the No. 21 loaded mine car causing fatal injuries. The cause of death was asphyxiation due to mechanical compression of the neck and trunk.
A contributing factor was that a positive acting stopblock was not provided on the loaded side of the rotary dump to prevent mine cars from drifting. Also contributing to the accident was the failure of the retarder system and the uncoupling of car No. 310 on the empty side of the rotary dump. The retarder which was designed to reduce strain on the cars while dumping, was not functioning. There was excessive wear of the shank of the rotating coupler and frame of the No. 21 mine car that contributed to the uncoupling while dumping.
An inspection of company training records and interviews with miners revealed that task training instructions given by management to rotary dump operators were not adequate. Management's instructions permitted rotary dump operators to enter the rotary dump without blocking loaded mine cars.
VIOLATIONS
- A 103(k) Order was issued to ensure the safety of miners until
a investigation could be conducted.
- A positive acting stopblock was not provided on the loaded side
of the rotary dump to protect persons from the danger of runaway
haulage equipment, a violation of 30 CFR 77.1605(p).
- The left brake on the empty side of the rotary was not
operative, the pushrod and clevis that activate the air chamber
were damaged, a violation of 30 CFR 77.404(a).
- The No. 310 mine car was not being maintained in safe operating
condition. The coupler assembly and frame were worn on the
rotating end of the car which caused uncoupling during the dump
cycle. The car was immediately removed from service a violation
of 30 CFR 77.404(a).
- Task training for rotary dump operators given by management did not recognize the hazards related to the assigned work procedures, a violation of 30 CFR 48.27(a)(1).
Respectfully submitted by:
Joseph R. O'Donnell Jr.
Coal Mine Safety and Health Inspector
Marshall J. Brighenti
Coal Mine Safety and Health Inspector
Approved by:
Joseph J. Garcia
District Manager
Related Fatal Alert Bulletin:
[FAB95C19]