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After bolting in the crosscut was completed, fallen roof material at the intersection in No. 1 entry was loaded up. A deflector line brattice was installed from the outby rib of the crosscut and extended across part of the intersection toward the face of No. 1 entry. (See sketch.) The inby corner at the intersection was cut and loaded, and the mining machine was trammed to the face, which was about 16 feet from the crosscut just driven. The cutting head was sumped to a depth of about 2 feet at the bottom of the coalbed at the right side of the place and was raised upward to complete the shear. Hard material was encountered at the roof, and sparks were produced when the cutting bits struck it. Gas liberating freely from the sump was ignited by the sparks. The flame appeared to dance up and down in the sump. The continuous-miner operator grabbed the water hose from the miner, the bolter on the right side opened the water valve, and a stream of water was directed into the sump. The flame was extinguished immediately. The assistant mine foreman was notified of the occurrence when he returned to the face region. Further mining was not done in the place during that shift.

During the investigation there were audible liberations of methane in the completed sump, and tests with electric methane detectors held against the coal indicated percentages above the lower flammable limit (off the scale). The methane was diluted at the face inasmuch as air sample bottle No. X-8940, collected at the face in the sump, contained 0.6 percent methane. The coal was 5-1/2 feet in height at the face, and the sump was 42 inches in width.

At the time of the investigation at the scene of the occurrence the line brattice was along the right side of the place and had been altered between the time of the ignition and the underground investigation. Later it was established where the line brattice actually was at the time of the ignition.

A spray on each cutting disk (pineapple) along the cutting chain at the front of the continuous-miner head and one spray in the hopper were not in proper operating condition at the time of the investigation. This was remedied promptly.

CONCLUSION

The ignition occurred when methane liberating freely at the face of the sump was ignited by sparks that resulted from cutting hard material. Contributory factors were lack of water being applied due to clogged sprays and not making the initial sump penetration on the line-brattice side of the place.

RECOMMENDATIONS

Compliance with the following recommendations may prevent a similar occurrence in the future:

1. Water sprays on continuous miners should be in proper operating condition when the miners are in operation.

2. Penetration at the face should begin on the ventilation (line brattice or tubing) side of the place.

ACKNOWLEDGMENT

The cooperation of officials, employees, the State mine inspector, and representatives of the United Mine Workers of America is gratefully acknowledged.

Respectfully submitted,

18/ Henry Zavora

Henry Zavora

Approved by:

18/ T. J. McDonald

T. J. McDonald
Acting District Manager
Coal Mine Safety District A

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Sketch of Scene of Coal Mine Gas (Frictional) Ignition

Gateway Mine

Gateway Coal Company
Clarksville, Greene County, Pennsylvania

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Mr. Ozonish. We have a report here of one that occurred just not too long ago but it was not an

ignition. This report was made by the U.S. Department of Interior, Bureau of Mines. A letter of information June 3, 1970:

Notice is hereby given that undersigned authorized representative of the Secretary of the Interior in making an inspection of this mine June 3, 1970, observed the violation of Section 306(b) of the Federal Coal Mine Health and Safety Act of 1969. The violation described below should be corrected as soon as ways and means of correction is available. Automatic circuit breakers were not provided for the cable of the auxiliary mine.

Now I am just going to read this, I don't want to go through the whole thing. I know you are pressed for time and we are glad we can get as much time off you as possible.

This is referring to water sprays and float dust. There is a hazard of coal dust right there. If you want this inspection, I will let you take this.

Senator WILLIAMS. What inspection is this?
Mr. OZONISH. This is June 3, 1970.
Senator WILLIAMS. Is that a regular inspection?

Mr. Ozonish. No; this is what we call a spot inspection where an inspector is sent around to just check.

Senator WILLIAMS. That was June 3 and this was a spot inspection. How many have you had since June 3?

Mr. Ozonish. Since June 3 I don't think we had any. The only time we had a Federal inspector come since that time was on a near fatality. We have near fatalities and the State inspector comes around or the Federal inspector comes around. We had two near fatalities since that inspection.

Senator WILLIAMS. Since this June 3?
Mr. OZONISH. That is right.

Senator WILLIAMS. And in response to that you had two inspectors come over?

Mr. Ozonish. We had two to investigate a near fatal accident. Senator WILLIAMS. And they came because of that near fatality? Mr. OZONISH. Yes.

Senator WILLIAMS. Without objection, the inspection letter of information will be inserted into the hearing record at this point.

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