Mucking and Loading Haul Truck Not Permitted Near Blast Site

By Ellen Smith

A blast site area was not “secure” where a front-end loader was mucking in the quarry pit below the bench where explosives were being loaded into blastholes ALJ David Barbour ruled, upholding a violation of §56.6306(c) against the blasting company Orica Nelson Quarry Services.

The blasting contractor was working at the Greenville Quarries, operated by Roadbuilders & Parkway Construction LLC in Greenville, Ky.

During an April 2009 inspection, the MSHA inspector found the contractor loading boreholes with explosives at the top of the highwall. According to the inspector’s notes, a Cat 990 loader was scooping up, and loading shot rock into a haul truck from against the face of the highwall beneath a portion of the highwall that had been loaded with explosives.

Drilling Pattern
The drilling pattern presented before ALJ Barbour showed 44 boreholes, 34-ft. deep extending from the top of the highwall to the bottom of the highwall. The MSHA inspector testified that 15 boreholes located on one side of the bench were loaded, but the lines were not yet connected. While the holes were to be approximately 10 ft. back from the highwall, the inspector was concerned that “bit wander” during the drilling process could have altered the location of the holes, and actually place the holes within 4 to 6 ft. of the highwall face in the vicinity of where the loader was operating.

The inspector believed that the 990 loader mucking against the highwall could cause a premature detonation if the bucket of the loader were to penetrate one of the loaded blastholes. In addition, the MSHA inspector said the blasting contractor knew the general vicinity of the miners in the pit, but did not know their exact location.

Orica argued that while boreholes on the left side were loaded, boreholes on the right side were not, and that was the side where the mucking was taking place. In addition, the boreholes were not yet tied together. The Orica employee that was loading the blastholes at the time estimated that there was at least 55 ft. between the loader and the loaded boreholes.

He also testified that he measured the distance at the time, but unlike the MSHA inspector who had the notes, he did not write down the measurement at the time. The blasting company witness also said that the area at the base of the highwall, below the loaded boreholes, was clean on the previous day, so it was his belief that the loader would not be mucking at the face in front of the loaded boreholes.

Orica also presented as a witness Michael Music, a former MSHA field office manager and previous chairman for MSHA’s Highly Explosive Standards Committee. While Music speculated that the distance from the edge of the highwall to four boreholes closest to the edge of the highwall, ALJ Barbour noted that Music was not present at the quarry the day of the inspection, and did not observe the conditions, so his testimony was not given the weight as the inspector’s testimony and notes.

ALJ Barbour said while the standard specifically allows haulage activity near the base of a highwall being loaded, the fact that the Cat 990 loader was mucking does not fit into the definition of haulage. “Here, the activity that triggered the violation was the loading of the haul truck,” the ALJ said.

On the issue of negligence, while the MSHA inspector listed the negligence as “moderate,” the Secretary requested that the negligence be increased to “high” and that the number of miners affected be increased from one (the loader operator) to four, which would have been all miners working in the pit.

The ALJ agreed. “In this instance, if a premature detonation occurred, the loader operator, the haul truck driver and the miners doing the loading on top of the highwall could be hit by flying rock and would have sustained broken bones, internal injuries or they could have been killed. The violation was clearly serious,” Barbour said.

However, on the issue of S&S, Barbour said the Secretary failed to prove that a detonation was reasonably likely to occur. While the MSHA inspector was concerned the loader might dig into a loaded borehole, his testimony was not supported by his notes that indicated the loader was mucking on the unloaded side of the bench. Even with allowances made for bit wander of one or two feet, the record failed to show that the loader was operating close enough for a detonation to happen, Barbour said.

Barbour refused the Secretary’s request to increase the penalty from MSHA’s proposed $2,282 to $11,307 – a request made in her brief, which Barbour called “a dubious practice.” If the Secretary wanted an increase in the penalty, he should have filed a motion to amend the penalty petition.

Barbour said an appropriate fine was $2,000 given the company’s size and the fact that the violation was promptly abated by moving the haul truck and the loader.

ORICA NELSON QUARRY SERVICES, 9/12/13, civil penalty proceeding, Docket No. KENT 2009-1178-M; 20 MSHN D-3547

30 CFR § 56.6306
Loading, blasting, and security…
(c) Once loading begins, the only activities permitted within the blast site shall be those activities directly related to the blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of holes, provided that reasonable care is exercised. Haulage activity is permitted near the base of a highwall being loaded or awaiting firing, provided no other haulage acces

Ellen Smith is the owner of Legal Publication Services, publisher of Mine Safety & Health News, She has been covering mining issues since 1987 and has won 31 journalism awards for her reporting, including the 2010 Magnum Opus Award for Outstanding Achievement in Custom Media. Ellen can be reached at 585-721-3211, or at [email protected]

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