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UNITED STATES DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION

SOUTHEASTERN DISTRICT
Metal and Nonmetal Mine Safety and Health

Surface Nonmetal Mine
(Phosphate)

Fatal Electrical Accident
October 20, 1999

South Fort Meade
Cargill Fertilizer, Inc.
Ft. Meade, Polk County, Florida
Mine I.D. 08-01183

October 20, 1999

by

Mitchell Adams Supervisory Mine Safety and Health Inspector Donald L. Collier Mine Safety and Health Inspector Dean F. Skorski Supervisory Electrical Engineer

Originating Office
Mine Safety and Health Administration
Southeastern District
135 Gemini Circle, Suite 212; Birmingham, Alabama 35209
Martin Rosta, District Manager



OVERVIEW


On October 20, 1999, Michael A. Storts, electrician, age 29, was fatally injured when he was electrocuted while working on a slurry pump. While Storts was changing the conductor connections to reverse the rotation of the pump motor another employee energized the circuit that provided power to the pump.

The accident occurred because mechanical work was performed on the electrical conductors before the circuit was locked out and suitably tagged. Storts had a total of five years, 3 months mining experience all with this company. He had four months experience as an electrician. He had received training in accordance with 30 CFR Part 48.

GENERAL INFORMATION


South Fort Meade, an open pit phosphate mine, owned and operated by Cargill Fertilizer, Inc., was located off County Line Road, about 10 miles south of Fort Meade, Polk County, Florida. The principal operating official was Don Thompkins, mine manager. The mine normally operated three, 8-hour shifts a day, seven days a week. Total employment was 200 persons.

Excavation of the phosphate was essentially a strip-mining operation in which the overburden was removed and placed in adjacent mined out areas. The underlying matrix was excavated with large draglines and deposited in shallow pits where hydraulic guns broke up the material. The resulting slurry was pumped through pipelines to a beneficiation plant for washing, screening, sizing, and flotation. The material was put in storage bins, then loaded into railcars for transportation to chemical plants for further processing.

The last regular inspection of this operation was conducted on September 13, 1999. A regular inspection was conducted following this investigation.

DESCRIPTION OF THE ACCIDENT


Michael Storts (victim) reported to work on October 19, 1999, at 7:00 a.m., his normal starting time. He completed his shift at 3:30 p.m. and left the mine site. At about 10:00 p.m., he along with the float crew, were called back to the mine because the face plate on the No. 1 lift pump had ruptured due to a pressure surge in the pipeline. The employees were to replace the impeller and pump shell.

Rupert Russell, field equipment operator, arrived back at the site, met with Antonio Garza, float crew leadman, and informed him that he was going to lock out the pumping system. Russell went to the pit pump and the No. 2 matrix pump and locked them out. When he went to the No. 1 matrix pump, the other members of the crew were already there. Before Russell could lock out the No. 1 matrix pump, Vernon Crawford, field supervisor, met with the crew and instructed Russell to use a loader to retrieve another pump casing to replace the old one. Russell proceeded to go get the pump casing; however, he did not inform Crawford or Garza that he had not locked out the No. 1 pump. Crawford left the area a short time later and went to assist Russell.

Storts arrived back at the mine at about 11:45 p.m. and was met by David Horn, electrician, who was working the night shift. Together they went to the pump. Horn opened the control breaker to the No. 1 pump and Storts de-energized the power supply by opening the electrical disconnect switch and then disconnected the leads.

The field crew cleaned out accumulated debris around the pump shell and removed the shell. To remove the impeller the power leads needed to be reversed to cause the pump to run in reverse. Storts reversed the leads, re-energized the power, and the impeller was removed without incident.

Then Horn threw the breaker in the open, or off, position, and Storts opened the disconnect, shutting off the power so the pump shell could be replaced. There was no indication that the disconnect had been locked out at any time during the removal of the impeller or switching of the disconnects.

As the field crew prepared to re-install the impeller, Russell told Garza that he had not locked out the power disconnect to the No. 1 matrix pump. When he heard this, Garza immediately proceeded to the switch to put his safety lock on it. Storts was disconnecting the power leads to reverse them to the normal position to enable the pump to run in the forward direction. Reportedly, Garza yelled to Horn and Storts that he was going to lock out the disconnect and thought he heard someone say "ok".

It was dark at the switch box and Garza did not have a flashlight with him. He felt for a lock but could not find one. Garza thought that the switch was still energized and flipped it to the closed position, energizing the circuit.

Storts was holding the connections when the circuit was energized. Horn, who was near Storts, yelled to Garza to open the switch, which he immediately did.

Russell and Garza immediately went to Storts and began administering CPR. The dispatcher at the mine was notified of the accident by radio and called the county Emergency Management System. Storts was transported to a local hospital where he was pronounced dead as a result of electrocution.

INVESTIGATION OF THE ACCIDENT


At about 12:45 a.m. on October 20, 1999, Harry Verdier, assistant district manager for MSHA's was notified of the accident by a telephone call from Douglas Wilson, safety and security manager for Cargill Fertilizer, Inc. MSHA began an investigation the same day with the assistance of mine management and mine employees. International Chemical Workers Union Council represented the miners and participated in the investigation.

DISCUSSION


1. Power was provided by Florida Power and Light to the mine site at 115,000 volts, reduced to 25,000 volts, and distributed to various substations throughout the mine. The 25,000 volts was reduced at the No. 1 matrix lift pump substation to 4,160 volts, wye, resistance grounded. Electricity was then supplied to the No. 1 pump controller by power cable. The controller was provided with TAW Custom Equipment, 3 pole, 400 amp, 5 KV switch, mounted on the outside of the controller cabinet on the north wall. The switch provided the circuit with a visible disconnect and was labeled to show the open and closed positions. The switch was also provided with a mechanical/electrical interlock to ensure the switch would not operate under load.

2. The accident occurred in the pit at the starter enclosure at the northeast corner of the skid-mounted controller for the No. 1 slurry lift pump for the No. 12 dragline. There was no artificial lighting on the north side at the enclosure. Two area lights were mounted on top of the controller cabinet at the southeast corner. Only one of these lights was in operation and was pointed toward the motor and pump installation located behind the controller on the south side. Employees had been provided with flashlights.

3. The pump was powered by a Westinghouse, 1500-horsepower, 4160-volt, 3-phase wound rotor motor. The face plate on the pump had ruptured due to a pressure surge in the pipeline and the impeller and pump shell needed to be replaced. To remove the impeller, two of the three-phase conductors to the pump motor needed to be manually switched and the rotation of the motor needed to be reversed, spinning off the impeller.

4. The starter for the pump was a Joslyn Clark, vacuum contactor, model MVC77U034A50, 400 amp, 4160-volt, and was located inside the controller. Control power for the starter was provided through a separate 220-volt circuit breaker located in an adjacent panel.

5. A tic tracer and "bang stick" belonging to Storts were found on the floor of the controller after the accident. The tic tracer was used to detect the presence of voltage. The bang stick was used to discharge any residual voltage on the conductors.

6. The ground near the controller was damp from the ruptured face plate. The weather was warm and clear.

7. The lock-out procedure used at this operation varied between departments. All electrical employees and maintenance employees had been issued and were required to use individual locks when working on equipment. The float crew used a different procedure in which the Supervisor and leaderman were assigned locks and were responsible for locking out equipment being worked on by members of the crew. There were three separate failures in the lock-out procedure which resulted in the accident.

The first failure occurred when the two electricians, both of whom had been issued locks, failed to properly lock out the system on which they were working to prevent it from being accidentally energized.

The second failure occurred when personnel assigned the responsibility of locking out for the float crew were distracted by other responsibilities and failed to properly lock the system out to prevent equipment being repaired from being energized.

The third failure occurred when one member of the float crew was allowed to actually lock out the power circuit, for another member who was working on the equipment.

CONCLUSION


The cause of the accident was the failure to lock and suitably tag out the disconnect switch for the circuit before work was being performed on the circuit. Contributing to the accident was the lack of sufficient illumination at the disconnect switch.

ENFORCEMENT ACTIONS


Order No. 7758490 was issued on October 20, 1999, under the provision of Section 103(K) of the Mine Act:
A fatal accident occurred at this operation on October 20, 1999, when an electrician was electrocuted while performing repairs on a the number one matrix lift pump for the number 12 dragline. This order is issued to assure the safety of persons at this mine until the mine or affected areas can be returned to normal operations as determined by an authorized representative of the Secretary. The mine operator shall obtain approval from an authorized representative for all actions to recover persons, equipment, and/or return affected areas of the mine to normal.
This order was terminated on October 21, 1999. Conditions that contributed to the accident have been corrected and normal mining operations can resume.

Citation No. 7787394 was issued on November 15, 1999, under the provisions of 104 (d) (1) of the Mine Act for violation of 30 CFR Part 56.12017:
An electrician was fatally injured at this operation on October 20, 1999, when he was electrocuted while performing repairs on the number one matrix lift pump circuit for the number 12 dragline. The disconnect switch for the 4160-volt circuit was inadvertently energized. The switch had not been locked or tagged out, or other measures taken to prevent the power circuit from being energized without the knowledge of the individual working on the circuit. Failure to lock and tag out the 4160-volt circuit before work began on it was a serious lack of reasonable care and is an unwarrantable failure to comply with a mandatory standard.
This citation was terminated on November 15, 1999. The company has conducted additional training regarding lock out and tag out procedures. Individual locks and tags are to be required for each employee performing work on the equipment or circuits. Hazards and requirements were discussed.

Order No. 7787395 was issued on November 15 1999, under provisions of Section 104 (d)(1) of the Mine Act for violation of 30 CFR Part 56.17001:
An electrician was fatally injured at this operation on October 20, 1999, when he was electrocuted while performing repairs on the number one matrix lift pump circuit for the number 12 dragline. The disconnect switch for the 4160-volt circuit was inadvertently energized. Overhead lights in the circuit did not provide adequate illumination sufficient to provide safe working conditions, or to determine if the 4160-volt disconnect was in the open or closed position. Failure to provide adequate illumination is a serious lack of reasonable care and is an unwarrantable failure to comply with a mandatory standard.
This order was terminated on November 15, 1999. A portable lighting fixture has been installed to illuminate the end of the skid-mounted controller where the visible disconnect is located. Other lights at the pumping location were repaired.

Related Fatal Alert Bulletin:
Fatal Alert Bulletin Icon FAB99M42

APPENDIX A

Persons Participating in the Investigation

Cargill Fertilizer, Inc.
Don Thompkins ............... mine manager
Carrol Moye ............... mining superintendent
Douglas Wilson ............... mine safety and security manager
James A. Weinreich ............... maintenance manager
Gary Fowler ............... plant superintendent
Christopher Hedges ............... safety supervisor
David Hart ............... electrical supervisor
James Gunn ............... shift supervisor
Vern Crawford ............... float crew supervisor
David Horn ............... electrician
Antonio Garza, Jr. ............... float crew leadman
Rupert A. Russell ............... float crewman
International Chemical Workers Union Council
Michael Sprinkler ............... director, health and safety department
R. Neal Dillard ............... representative
Michael V. Chester ............... president, local 841c
Mine Safety and Health Administration
Mitchell Adams ............... supervisory mine safety and health inspector
Donald L. Collier ............... mine safety and health inspector
Dean Skorski ............... electrical engineer
APPENDIX B

Persons Interviewed

Cargill Fertilizer, Inc.
Vern Crawford ............... float crew supervisor
David Horn ............... electrician
Antonio Garza, Jr. ............... float crew leadman
Rupert A. Russell ............... float crewman