ForConstructionPros.com

When Arizona Public Service (APS) needed to replace the aging wastewater storage pond at the Palo Verde Nuclear Power Plant, one of the largest nuclear power plants in the world, plant managers called on Asphalt Busters to provide a stabilization solution for sloping sides of the new 40-acre pond.

The treated wastewater is converted to steam in power plant operation to generate electricity. Once used, the remaining water is then pumped to an evaporation pond (more on that later).

As an expert in soil stabilization, Asphalt Busters recommended using an 8 percent cement additive to treat the outside soil to be used in constructing the sloped side walls of the new pond. To ensure that the proposed construction method would meet APS's stringent standards, the contractor performed an onsite demonstration to showcase its spreading and mixing capabilities.

During the demonstration, several air quality tests were made to verify that Asphalt Busters could indeed meet the strict dust/emissions requirements that the plant operation must adhere to under federal regulations. Samples of the cement stabilized matter were also tested to verify that the contractor could also meet the strict spreading, mixing and moisture requirements of the project.

For the actual pond construction, Asphalt Busters used a level mixing area adjacent to the pond structure to spread over 200 truckloads (4,550 tons) of the cement additive (which was applied at a rate of 8 percent of the total combined volume to be mixed) and then injected over 1.4 million gallons of water at 200 to 425 gallons per minute to the treated soil before mixing to a depth of 12 inches in order to produce 55,000 cubic yards of material for the sloped side wall construction.