News Releases

Computerized Tracking System Reduces Waste, Saves Dollars at Power Plant

Jun 6, 1996

Sierra Pacific Power Company
Contact: Karl Walquist/Robert Sagan
Phone: (775)834-4345

For Immediate Release

Waste management has been improved at Sierra Pacific's Valmy Station Power Plant near Battle Mountain due to installation of a computerized system that keeps track of the many materials used at the facility. By recycling wastes and replacing hazardous products such as cleaning solvents with non-hazardous substitutes, the utility has reduced the amount of waste produced by the coal-fired power plant by 88 percent over the past two years.

In 1993, Sierra Pacific disposed of 651,362 pounds of waste at Valmy. By 1995, the total was reduced to 79,586 pounds, according to Mari Gilbert, an environmental engineer with the utility. Previously, a large percentage of the waste produced at the plant had to be transported to landfills and buried, or incinerated. (Editors'note: These totals do not include fly ash, the waste material produced by coal combustion at Valmy.)

"The computer program helped us to identify and monitor 36 different waste streams," explained Gilbert, who introduced the new system at the power plant in 1993."We had been tracking everything by hand, which was more time consuming and made it difficult to effectively coordinate everyone's efforts.

"Additional training and the employees'commitment to teamwork also contributed to the success of our waste management program," she added.

Valmy's annual disposal costs have dropped from $52,819 in 1993 to $15,960 in 1995 due to the computerized tracking system, Gilbert said, adding the $1,500 waste management computer software quickly paid for itself.

The biggest single cost savings has come from recycling the oil used to lubricate equipment at the power plant. In 1993, about 108,000 pounds of used oil was shipped off site for disposal at a cost of 35 cents per gallon. Two years later, only 25,000 pounds had to be hauled away. Starting in 1996, the oil will be mixed with diesel fuel and used to ignite the burners for the two coal-fired electric generating units at Valmy.

Additional savings came from replacing hazardous cleaning solvents with non-hazardous solvents. Gilbert said that after they are used to clean equipment parts at Valmy, the non-hazardous solvents will be mixed with the used lube oil and diesel for burner ignition. Previously, the utility had to pay for solvent disposal as a hazardous waste.

Besides office paper and cardboard, among the other items recycled at Valmy are lead-acid batteries, fluorescent bulbs and oily rags. Gilbert said the company has also reduced costs by switching from steel drums to less costly plastic and cardboard containers for the disposal of non-hazardous materials.

Fly ash -- the ash remaining after coal is burned to fuel the generating units -- is produced in large quantities at Valmy, and much of it is recycled into concrete filler. Approximately 12,000 tons of this non-hazardous material were recycled in 1995.

Fly ash from only one of the generating units at Valmy is suitable for this purpose. Currently, ash from a second unit cannot be used as concrete filler because of its high lime and carbon content and is disposed of on site.

"We're hoping to be able to recycle this ash into a special type of concrete blocks," Gilbert said, adding that this was successfully attempted on a trial basis in 1994.

In addition to expanding the waste reduction and recycling programs at Valmy, the next step for Sierra Pacific will be to introduce similar computerized waste handling procedures at the utility's other facilities. The Pollution Prevention Project is being implemented throughout the company in 1996.

"What the waste management program at Valmy has demonstrated is that pro-active environmental policies and cost savings go hand in hand," Gilbert noted.