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MSHA - Fatal Investigation Report


Southeastern District
Metal and Nonmetal Mine Safety and Health

Accident Investigation Report
Surface Nonmetal Mine

Fatal Falling or Sliding Material Accident

Black River Plant
Dravo Lime Company
Butler, Pendleton County, Kentucky
I.D. No. 15-05484

October 12, 1998


Larry R. Nichols
Supervisory Mine Safety and Health Inspector

Charles E. McDaniel
Mine Safety and Health Inspector

Stanley J. Michalek, P.E.
Civil Engineer

Originating Office
Mine Safety and Health Administration
135 Gemini Circle, Suite 212
Birmingham, Alabama 35209

Martin Rosta
District Manager


Michael C. Sanzere, quality control manager, age 45, was fatally injured at about 9:40 a.m. on October 12, 1998, when a stone bin failed and the material collapsed the roof on the building where he was working. Sanzere had a total of 22 years mining experience, all with this company, in this job. He had received training in accordance with 30 CFR Part 48.

MSHA was notified at about 10:40 a.m. on the day of the accident by a telephone call from the employee relations manager for the mining company. An investigation was started the same day.

The Black River Plant, a limestone crushing and calcining operation, owned and operated by Dravo Lime Company, was located along the Ohio River, 12 miles northeast of Butler, Pendleton County, Kentucky. The principal operating official was Mark Davis, vice president. The plant was normally operated three, eight-hour shifts a day, seven days a week. A total of 140 persons was employed.

The operation consisted of a stone plant, the lime plant kilns and the lime plant storage and shipping area. Limestone was conveyed to the plant where it was crushed and sized, then transported by conveyor belts to the kiln feeder bins. Hydrated lime from kilns was cooled and screened, then stored for shipping. The finished product was shipped by barge, rail and truck to customers and used primarily in water treatment plants.

The last regular inspection of this operation was completed on July 23, 1998. Another inspection was conducted at the conclusion of this investigation.


The lime plant kilns, where the accident occurred, consisted of three stone bins, three coal bins and a conveyor system that fed material into the stone bins. A two-story building, located beneath the No. 2 stone bin contained the operator stations and the conveyor that transported material from the stone bin to the kiln. Adjacent to the two story building was a concrete block structure housing the old laboratory/lunchroom.

The bin was constructed of steel plates welded together to form cylindrical and conical sections. It was 22 feet above ground and suspended by four steel columns. The inside diameter of the cylinder was 28 feet. The bin was 36-feet high and sloped to 17 feet. The top was constructed of one-quarter-inch-thick steel plate. The bottom 5 feet of the cylinder was a ring beam comprised of a 6-inch-wide by 7/8-inch-thick compression ring, 20 equally spaced 6-inch-wide by 1-1/4-inch-thick vertical stiffeners and a 6-inch by 7/8-inch-thick upper ring. Design drawings for the bin showed that the plates specified for the area of the cylinder above the ring beam were to be one-quarter-inch thick and the area within the ring beam was to be three-eighths-inch thick.

The lower portion of the bin was an inverted cone 23-feet high. The top diameter of the cone was such that it could just fit within the diameter of the cylinder. The bottom of the cone consisted of a discharge hole with a diameter of 1.5-feet. The design drawings indicated that the cone section was to be built of three-eighths-inch-thick plate. The top edge of the cone was welded around its perimeter to the inside edge of the cylinder portion of the bin. This was the only means of support for the cone section.

The limestone stored in the bin was 1.5- to 2-inches in diameter. The bin was normally filled with 500 to 600 tons of material. The bin had been filled with approximately 500 tons of stone 30 to 45 minutes prior to the accident.

Following the accident, the lower portion of the bin cylinder section was examined with the use of a lift platform. Areas within the ring beam were corroded and abraded to the point that it was possible to see through the metal wall of the bin.

Heavy corrosion was observed above each of the rings on the outside surface of the bin. Along the northeast side of the bin, where the spillage was first reported, it appeared that the cone to cylinder weld was intact and that the cone plate had torn. Around the perimeter of the bin, it appeared that as the split widened, it followed the path of least resistance by sometimes tearing through the cylinder plate and sometimes through the cone plate.

Design drawings noted that the bin had new plating added in December 1984. It did not appear that the plating had been replaced since that time. Work orders indicated that work was performed on this bin in the past; however, it was not clear what specifically was done.

Numerous pieces of the cone were cut away during recovery operations and the portion of the cone where the initial split was observed could not be conclusively identified. However, a majority of the upper edge of the cone perimeter was available for examination. It appeared that a substantial amount of plate thickness had been lost through corrosion, abrasion or both.

Measurements taken with a caliper showed that the thickness of the cone plate was approximately 0.12 inches. Measurements taken around the compression rings showed their thickness varied from 3/4-inch to 7/8-inch. It could not be determined whether areas along the top of the cone had been perforated by corrosion and abrasion.

The company had not established a preventive maintenance program for the stone bins, they were checked visually during workplace examinations. If stone was observed falling from a bin, the bin was patched.

On the day of the accident the weather was sunny and mild. Material in the bin had been washed and was slightly damp.


On the day of the accident, Michael Sanzere (victim) reported for work at 7:00 a.m., his normal starting time. He, along with Paula Arthurs, lab technician, started calibrating equipment and entering information into the computer system. At about 7:50 a.m., they left the new laboratory and traveled by pick-up truck to various locations collecting samples to be processed for analysis.

At about 8:00 a.m., they arrived at the old laboratory and started processing samples. At about 8:30 a.m., Sanzere left to collect additional samples from the kiln area. Shortly after he returned, Arthurs left the lab.

Carl Bay, Jr., conveyor man, was working in the kiln building when he heard a noise and came out. He saw material from the No. 2 stone bin hitting the metal roof on the old laboratory building and immediately radioed Kenneth Buser, plant maintenance superintendent, to inform him of the condition. At about 9:40 a.m. Bay saw Sanzere standing in the doorway of the lunchroom looking at the stone falling from the roof. Sanzere then turned and went back inside the building.

Buser saw material spilling from the cone section of the bin and estimated the split to be about a foot long which quickly propagated. As material rushed out, the remainder of the cone failed and released the 500 tons of material which collapsed the roof of the old laboratory.

The administrative clerk in the plant office notified the county ambulance service while others began searching for Sanzere. Fire department rescue crews from various communities responded to the call and began recovery operations. For approximately 36 hours, material was vacuumed into trucks until enough material had been removed to locate Sanzere. He was removed from the property at 1:05 a.m. on October 14th.

It is believed that Sanzere went back into the lunchroom to exit through the rear door, away from the falling stone. He was found approximately 4 feet from this door beneath the debris.


The accident was caused by failure of the mine operator to properly maintain the integrity of the bin. The corrosion and abrasions of the steel plates had compromised the integrity of the structure to the extent that it could no longer carry the load.


Order No. 4555356 was issued on October 12, 1998, under the provisions of Section 103(K):

On October 12, 1998, 0940 a fatality occurred at the surface lime plant old sample area. This order is for 1&2 stone bins, 1&2 coal bins which feed raw material to the 1& 2 kilns and cooling tunnel areas. This order is issued to assure the safety of persons at this operation until the affected areas can be returned to normal operations as determined by an authorized representative of the Secretary.

This order was terminated on October 29, 1998. Conditions that contributed to the accident have been corrected and normal operations can resume.

Citation No. 7777470 was issued on October 14, 1998, under the provisions of Section 104(d)(1) for violation of Standard 57.14100(b):

A fatal accident occurred at this operation on October 12, 1998, when a quality control manager who was working inside a building located under the No. 2 stone bin was crushed by stone and debris, when the cone section of the bin failed. The bin contained approximately 500 tons of stone which collapsed the roof of the building, burying the victim. Corrosion along the compression ring, upper ring, bin walls and cone-cylinder junction was prevalent and obvious. The mine operator had examined the bin 2 to 3 months prior to the failure and knew or had reason to know of the deteriorated condition. Failure to take corrective action is a serious lack of reasonable care constituting more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.

This citation will be terminated when the No. 2 stone bin has been replaced and the company implements procedures to routinely inspect the bins and make repairs, as necessary.



List of Persons Present During The Investigation:

Dravo Lime Company
Wentzel Marcus Davis .......... vice president operations
Roger Rowe .......... director of safety
Thomas G. Galbreath .......... safety manager
Garth Kuhnhein .......... vice president engineering
Kenneth Buser .......... plant maintenance superintendent
Kenneth Ray O'Brien .......... maintenance superintendent
Ronnie Clos .......... plant production supervisor
Carl Bay Jr. .......... conveyor man
Sammy Linville .......... kiln operator
Phillip Short .......... mechanic
Paula Jane Arthurs .......... lab technician
Marcus McGraw .......... attorney

United Steel Workers Of America
Ernie Gillespie .......... president of local-162
Allen Williamson .......... union safety representative

Mine Safety and Health Administration
Larry Nichols .......... supervisor mine inspector
Charles McDaniel .......... mine safety and health inspector

Related Fatal Alert Bulletin:
Fatal Alert Bulletin Icon FAB98M44