A report issued by the federal government blames the gravel company for the death of one of its dredge operators last fall.
‘Management policies, standards, and controls were inadequate and failed to ensure that the dredge was maintained in safe operating condition,? according to the report issued April 6 by the U.S. Department of Labor’s Mine Safety and Health Administration (MSHA).
Lifelong Oxford resident Mark J. Hickmott drowned October 10, 2006 when the floating clamshell dredge he was operating in a gravel pit, owned by American Aggregates of Michigan, capsized in approximately 115 feet of water.
‘The dredge capsized because it had been modified and used beyond the design capacity intended by the manufacturer,? according to the MSHA report.
American Aggregates was issued two citations by the MSHA. The dollar amount of the fines has not yet been released.
The 45-year-old husband and father of two had eight years experience operating this dredge, which was located just south of Oakwood Road and west of M-24.
Erected at the mine in 1998, the dredge was manufactured with rectangular pontoons to keep it afloat and used a clamshell bucket to extract sand and gravel from the bottom of the lake. The bucket was hoisted and transported by a trolley rail system to an on-board hopper where the material was deposited.
According to the MSHA report, modifications were made that ‘impacted the stability of the dredge and created a hazard to miners.? The report concluded:
n ‘Procedures had not been established to ensure that leaks in the dredge pontoons were repaired. Sump pumps were installed in four leaking pontoon cells . . .One pontoon cell was allowed to stay filled with water.?
n ‘Procedures had not been established for modifying the original design of the dredge. Additional steel plating had been added on the front end of the dredge to support the storage of large boulders encountered while mining. Additional steel plating had also been added to the crusher feed chute.?
This additional steel plating increased the dredge’s weight by 8,290 pounds or 4.14 tons, according to the report.
Five or six boulders stored on the dredge at the time of the accident added an estimated 12.3 to 13.7 tons to the pontoon supporting the digging end, the report stated.
n ‘Procedures had not been established to ensure the high dredge overload and full hopper alarm switches were properly positioned and functioning within the specifications set by the manufacturer. The switches were set to permit approximately 1? inches of freeboard. The dredge was designed for a minimum 12 inches of freeboard to prevent overloading the dredge.?
Freeboard refers to the distance from the waterline to the main deck of the floating structure.
According to the report, the dredge was equipped with four draft gauges that acted as overload alarm sensors.
‘When water levels reached a gauge, the clamshell operation would shut down. The manufacturer recommended the draft gauges be set to activate when the dredge deck came within 12 inches of the water surface,? the report stated.
Two of the four gauges were recovered and examined by investigators.
‘Calculations showed that the draft gauges would not activate until the deck was approximately 1.5 inches from the water surface,? the report stated.
The dredge was also equipped with an alarm to guard against overloading the hopper with mined material. ‘The sensor, when activated, would not permit the clamshell to be positioned over the hopper and dump,? according to the report.
The manufacturer recommended this alarm sensor activate when the discharge end of the dredge came within 14-15 inches of the water surface.
‘Investigators determined that this sensor was not functional at the time of the accident,? the report stated.
R. Scott Carson, vice president/general manager of American Aggregates of Michigan, said the company is in the process of challenging the report’s findings.
‘We’ve seen the report and we are contesting the report,? he said. ‘We don’t agree with a lot of the conclusions they came up with.?
‘It’s certainly within our rights to do it and they weren’t surprised,? Carson explained. ‘There were just so many unknowns about the incident that we wanted to better understand how they came to the conclusions that they came up with.?
Carson did not wish to get into the specifics of which findings his company is contesting and why.
‘Right now, our attorney is handling it,? he said. ‘There’s a discovery going on with information being shared back and forth. I would like to think at some point in time there should be a hearing.?
For now, the American Aggregates Oxford Plant, where Hickmott worked, remains closed, as it has since two weeks following his death. But Carson insisted the reason is pure economics.
‘The fact that the Oxford Plant is not up and running has nothing to do with that incident,? he explained. ‘The plant is not running because of the economy. The economy is just terrible. We had decided to close down a couple of our operations ? Oxford being one of them.?
The Oxford Plant employed 23-25 workers.
‘We felt we did not need to run that operation this calender year and it remains to be seen how much longer it’s going to be shut down, but it’s pretty safe to say it will probably not run this year,? Carson said. ‘It’s not like business is all the sudden taking off. It’s as bad, maybe even a little worse than what we had thought.?
American Aggregates? Ray Road Plant is still operating and seems to be generating enough material to meet the current market demand, according to Carson.
No lawsuits related to Hickmott’s death have been filed against either American Aggregates of Michigan or it’s parent company, the Detroit-based Edward C. Levy Company, which has owned the local gravel operation since 1997.
Hickmott’s widow, Debbie, said she is aware of the MSHA report, but declined to comment at this point.