Two gas and coal dust explosions, the first at approximately 11:45 a.m., March 9, 1976, and the second at approximately 11:30 p.m., March 11,1976, occurred in the 2 Southeast Main area of the Scotia Mine, Scotia Coal Company, Ovenfork, Letcher County, Kentucky. All 15 men working in the 2 Southeast Main area at the time of the first explosion died as a result of the explosion. Ninety-one men in other parts of the mine at that time reached the surface without mishap. At the time of the second explosion, 13 men were underground near the entrance of 2 Southeast Main; 11 died as the result of the explosion and 2 repairmen working a short distance outby escaped without injury.
MESA investigators believe that the first explosion originated near No. 31 crosscut in 2 Southeast Main when a mixture of methane and air was ignited by an electric arc or spark from a battery-powered locomotive. Forces of the explosion spread to all five 2 Southeast Main entries, extended into 2 Left Section off 2 Southeast Main and dissipated as they reached the Northeast Main junction.
MESA investigators believe that the second explosion originated near the entrance of, or in, 2 Left Section off 2 Southeast Main when a methane-air mixture was ignited by one of five possible sources: an electric arc or spark from a battery-equipped deluge system; three battery-equipped telephones; scoop batteries; residual fires; or a frictional spark from a fall of mine roof on a roof-bolting machine. The forces of the explosion extended throughout 2 Left Section and all five entries of 2 Southeast Main, spread north and south in all entries in both panels of Northeast Main, and dissipated near the junction of 3 Southeast Main in the northern direction and near the junction of Southeast Main in the southern direction.
The Scotia Mine, Scotia Coal Company, is located near Ovenfork in Letcher County, Kentucky, on the Poor Fork of the Cumberland River, approximately 14 miles northeast of Cumberland, Harlan County, Kentucky. The Scotia Coal Company is a wholly owned subsidiary of the Blue Diamond Coal Company, Knoxville, Tennessee.
The Scotia Mine was started in July 1962. It was originally opened by nine slope entries into the Imboden coalbed, which averages 72 inches in thickness locally. The slope entries were developed into the coalbed and inclined due to the pitching characteristics of the coalbed from its outcrop.
In 1975, an additional opening in the form of a concrete lined 13.5-foot diameter shaft, 376 feet deep, was raise-bored near the face areas of Northeast Main. The lining of the shaft was completed July 21, 1975, and work was begun to install an automatic elevator. On March 9, 1976, such work had not been completed and the shaft was being used only as an intake air opening.
Of 310 employees, 275 worked underground on two coal producing shifts and one maintenance shift
per day, 5 days a week. Approximately 2,500 tons of coal were produced daily on six active sections, consisting of five continuous mining sections and one conventional mining section.
Numerous tests by the Bureau of Mines have established that coal dust having a volatile ratio of 0.12
and higher is explosive. The volatile ratio of the coal in 2 Southeast Main is 0.395.
The last Federal inspection of the entire mine was completed on February 27, 1976.
On March 8, 1976, on the evening shift, a Federal Coal Mine Inspector conducted a Health and Safety Technical Inspection of 2 Left Section off 2 Southeast Main.
Mine Conditions Immediately Prior to the Explosion
The weather on March 8, 9 and 10, 1976, was cold and cloudy. By late evening on March 11, it was clear and the temperature had increased from 320 to 500 Fahrenheit.
MESA investigators believe that the slight change in atmospheric pressure did not contribute materially to the explosion.
On the morning of the explosion, March 9, 1976, the day shift (7:00 a.m. - 3:00 p.m.) crew of 106 men entered the mine and were transported to their working areas by battery-powered portabuses and locomotives. Of the 106 men underground, 13 were in 2 Southeast Main and 2 Left Section off 2 Southeast Main (explosion area). Of those 13 men, nine men under the supervision of Virgil Coots, Section Foreman, were producing coal in 2 Left Section; two men were building overcasts at the mouth of 2 Left; and one man was tending the 2 Left belthead located at the mouth of 2 Left in No. 22 crosscut between Nos. 2 and 3 entries of 2 Southeast Main.
According to his testimony at the official hearings, on the morning of the explosion J. P. Feltner, Underground Construction Foreman, called Richard Combs, General Mine Foreman, about 7:30 a.m., after all the mantrips and men had entered the mine and told Combs that he would have a load of steel rails delivered from 1 Right off 2 East to 2 Southeast Main.
Combs and Feltner had discussed delivery of the load of rails to 2 Southeast Main several days prior when Combs had expressed a need to extend the track in 2 Southeast Main preparatory to reactivating the section. After Feltner arranged to have a motor crew pick up the rails and deliver them to 2 Southeast Main, he traveled to 2 Left Section in search of a rail bender and oxygen-acetylene tanks. He stated that James Bentley was with him while he was in 2 Left Section. Feltner did not make tests for methane or take air measurements while he was in this area of the mine, nor did he go inby 2 Left Section. Feltner stated that there was no check curtain across the track going into 2 Left, but he observed a piece of plastic along the track on the mine floor between Nos. 2 and 3 entries, near where the check curtain was supposed to have been hung. He stated that he was unaware at that time that the absence of a check curtain at this location caused a short circuit of the air current which was ventilating 2 Southeast Main inby 2 Left.
Feltner left the 2 Southeast Main area and traveled to the mouth of Northeast Main where he met the motor crew with a load of rails. The motor crew, operating the Nos. 6 and 8 battery-powered locomotives, had stopped at the charging station at the mouth of northeast Main to charge the batteries on the No.6 locomotive. Feltner stated that two locomotives were used to transport the load of rails because the batteries on the No.6 locomotive were discharged and only one set of trucks was operating the No.8 locomotive. The No.6 locomotive, a 7-ton Goodman, equipped with an air compressor for the pneumatic braking system, was operated by Roy McKnight.
The No.8 locomotive, an 8-ton Westinghouse equipped with a mechanical braking system, was operated by Lawrence Peavey. The two locomotives were coupled and the truck load of rails was in front coupled to the No.8 locomotive. Feltner stated that the motor crew left the mouth of Northeast Main pushing the truck load of rails toward 2 Southeast Main about 11:35 a.m. He stated that it would have taken the motor crew about 10 minutes to reach 2 Southeast Main inby 2 Left Section. He stated that the motor crew did not have gas detecting equipment, and that he had not at any time instructed them to make any tests or examinations of 2 Southeast Main inby 2 Left before entering the area. He thought that the area inby 2 Left had been preshift examined because it was on intake air.
Feltner stated that he left the mouth of Northeast Main at the same time as the motor crew and traveled to Southeast Main where some of his crew were setting timbers along the track haulage road approximately 800 feet inby the Southeast Main belt drive. Shortly after he arrived at this location, at approximately 11:45 a.m., he felt a gust of air moving outby opposite to the ventilating current's normal direction and observed rock dust in suspension. He thought that the gust might have been caused by a crushed out stopping outby and he took his crew to investigate. They had traveled outby about 600 feet when the ventilating current reversed to normal direction. After Feltner learned that an explosion had occurred he contacted all active sections of the mine except 2 Left off 2 Southeast Main.
According to his testimony given at the official hearings, James Bentley made an inspection of the abandoned 2 Left Section off Northeast Main on the morning of the explosion. He found that a regulator was open approximately four feet wider than he had originally set it after the section was abandoned. After completing his inspection of this section he returned to the regulator and closed it to the original position. He took an air measurement and then walked to the No.3 belt drive in Northeast Main near the entrance of 3 Southeast Main where a telephone was located. He called Lawrence Cohen, Section Foreman in the Left Panel Southeast Main, and advised Cohen of his location. Bentley asked Cohen to take an air measurement on the Left Panel and call back. Bentley then called Virgil Coots, Section Foreman in the 2 Left section off 2 Southeast Main, and told Coots that he had inspected 3 Southeast, Right Panel Northeast Main, Northeast Main and 2 Left Section off Northeast Main. Bentley told Coots that he found the regulator in 2 Left section off Northeast Main open about four feet wider than it was supposed to be and that his closing of the regulator to its original position should increase the ventilation on 2 Left Section off 2 Southeast Main. Bentley asked Coots how much air did he have and Coots replied that he had just lost his air.
Coots told Bentley that he would go out to the mouth of 2 Left Section where two men were building overcasts, and determine if the men had removed a stopping which could have short-circuited the ventilation. Approximately two minutes later, about 11:45 a.m., the explosion occurred.
The motor crew delivering the truck load of rails had reached their destination at the end of the track in 2 Southeast Main when the explosion occurred. Including the two locomotive operators, there were 15 men in the 2 Southeast Main area when the explosion occurred. All died as a result of the explosion.
According to available evidence, when the explosion occurred, John Hackworth, belthead attendant, was at the 2 Southeast Main belt drive, located in No. 3 entry Left Panel Northeast Main. He was rolled a short distance by the forces of the explosion from 2 Southeast Main but was not seriously injured. He immediately called the surface and reported what had happened. Failing to establish communications with anyone in 2 Southeast Main, Hackworth donned his self-rescuer and proceeded into 2 Southeast Main to investigate. Reportedly, he traveled approximately 2,200 feet without making contact with anyone before he was forced to retreat.
Federal Inspectors West, Sample and Bowman entered the mine with two rescue teams equipped with self-contained breathing equipment at approximately 4:30 p.m. After the fresh air base had been established, recovery and rescue efforts inby the fresh air base were accomplished by mine rescue teams under oxygen.
The first body was discovered by a mine rescue team at 10: 18 p.m., at No. 22 crosscut in No. 2 entry of 2 Southeast Main, approximately 50 feet inby the 2 Left belt drive.
The Nos. 2, 3, and 4 bodies were found in the Nos. 1 and 2 entries of 2 Southeast Main near the entrance of 2 Left Section. The Nos. 5, 6, and 7 bodies were found along the No.4 entry of 2 Left Section. The Nos. 8, 9, 10, 11, 12 and 13 bodies were all found together along the right rib of the No.5 entry in 2 Left Section, behind a partially constructed barricade. Evidence indicated that some effort had been made to construct a barricade by hanging a plastic check across the mouth of No.5 entry. However, the left side of the check was not fastened to the rib when discovered by the rescue team. About 1:20 a.m., March 10, the last two bodies were found in No. 4 entry of 2 Southeast Main near the battery locomotives located between Nos. 31 and 32 crosscuts.
J. B. Holbrook, Don Creech, Don Polly, James Sturgill, Monroe Sturgill, James Williams, John Hackworth and Glen Barker, Scotia employees, and Grover Tussey, Richard Sammons and Kenneth Kiser, Federal Coal Mine Inspectors, were in the vicinity of the roofbolting machine, and Collins and Parker were in the process of removing the coupler from the pump trailing cable when another explosion occurred in the 2 Southeast Main area at approximately 11:30 p.m.
Collins and Parker heard the explosion and then felt pressure and heat. The atmosphere became so dusty that their visibility was limited to about 12 inches. They put on their self-rescuers, found a telephone line, and holding to each other, followed it to the main line track. They continued holding to each other, and followed the telephone cables out the track entry toward the surface. They arrived at the junction of Northeast and Southeast Main before visibility improved sufficiently for them to recognize their surroundings. After arriving at the Northeast Main belt head, Parker called the surface supply house, reported the explosion and asked for transportation. They proceeded out the track entry. When they arrived at the mouth of 1 West, they heard someone paging them on the mine telephone and Parker answered. He was told that transportation was on the way and to wait at that point. They, however, continued out the track entry to about one-half mile from the surface, where they were met by Richard Combs and Federal Coal Mine Inspector Davis who transported them to the surface.
Approximately 9:45 a.m., West, Merritt and McKnight were withdrawn from the mine shaft. The Nos. 1 and 2 Westmoreland Coal Company and the National Mine Corporation mine rescue teams, and Clemons were lowered into the shaft. Clemons briefed the mine rescue teams at the bottom of the shaft. The Westmoreland teams were instructed to travel along the Northeast Main track entry, open face, in intake air toward 2 Southeast Main. The National Mine Corporation rescue team was instructed to stay at the bottom of the shaft as a back-up team. The Beth-Elkhorn team was standing by on the surface. One of the Westmoreland teams arrived at the mouth of 2 Southeast Main approximately 12 o'clock noon, March 12, and found 11 bodies. After determining that there were no signs of life, the teams were ordered to return to the surface without recovering the bodies because of the possibility of another explosion. All persons were returned to the surface by 1 :02 p.m.
All parties concurred that the chance of another explosion was too great to permit anyone to reenter the mine and a consensus decision was reached to seal the mine on the surface. Preparations to seal began immediately and all openings had been closed by 2:10 p.m., March 19, 1976.
At 2:10 p.m., on March 15, 1976, a 104(a) Order was issued by Rick P. Keene to cover the entire mine.
MESA investigators conclude that the explosion of March 9, 1976, resulted from inadequate ventilation. The operation of electric equipment that was not maintained in compliance with Part 75, Title 30, CFR, and which contained components that created incentive arcing during normal operation in an area where methane had accumulated and where the required examinations had not been made prior to the operation of the electric equipment in the area, were contributing factors of the explosion.
Activating and working of the 2 Left Section for a period of approximately one month prior to the first explosion without establishing permanent ventilation permitted the short-circuiting of the ventilating current at the entrance of 2 Left Section for extended periods of time. This resulted in inadequate ventilation in 2 Southeast Main inby 2 Left, allowing methane to accumulate. The construction of plastic checks across Nos. 4 and 5 intake entries of 2 Southeast Main on the evening before the explosion completely restricted the air that would have ventilated 2 Southeast Main inby 2 Left and increased the hazard by permitting methane to accumulate more rapidly. Pre-shift examinations were not made in 2 Southeast Main inby 2 Left on the morning of March 9, nor was an examination made prior to the electric equipment entering the area. Therefore, the methane accumulations were not detected. The operators of the Nos. 6 and 8 battery locomotives were instructed and permitted to operate this equipment in this area, precipitating the explosion. Although it cannot be determined with certainty which of the sources of arcing on the two locomotives ignited the methane, the most likely source of ignition was the arcing created by the open type controller on the No. 6 Goodman locomotive when the controller was turned to the "off" position by the locomotive operator after reaching his destination at No. 31 crosscut, 2 Southeast Main. Coal dust entered into the explosion only to a minor degree. Pressure relief inby and outby the ignition point prevented high pressure and flame velocity.
MESA investigators conclude that the explosion of March 11, 1976, resulted from a lack of sufficient air to ventilate the area in 2 Southeast Main inby No. 22 crosscut, including the 2 Left Section, and remove from the mine the known methane accumulations. The lack of air prohibited safe and timely completion of the recovery operations.
The planning and subsequent unsuccessful attempts to increase the ventilation in 2 Southeast Main consumed approximately 45 hours. During this period, methane increased to an explosive concentration in
the unventilated explosion area, which had not been completely explored and where battery-powered equipment was known to be present. Efforts to increase the ventilation in 2 Southeast Main failed primarily because of the inaccurate mine map which was prepared by the company and used by officials to develop recovery plans. This contributed to the second explosion. Some possible contributing factors were that the planners, controllers, and directors of the rescue and recovery operations did not give due consideration to the potential ignition hazard of the battery-powered equipment in the unventilated and contaminated environment of the 2 Southeast Main area and to the increased risks associated with prolonged recovery efforts in the area and exposure to such conditions. The methane was ignited near the entrance of or in 2 Left Section off 2 Southeast Main by one of five possible ignition sources: An electric arc or spark from a battery-equipped deluge system; three battery equipped telephones; the scoop batteries; a frictional spark from a fall of mine roof on a roof-bolting machine; or heat from residual fires. While it cannot be definitely determined which source ignited the methane, MESA investigators conclude that the most likely ignition source was a frictional spark created when a section of mine roof fell on the roof-bolting machine located near the face of No.2 entry in 2 Left Section. Coal dust entered into the explosion and aided in its propagation.