Birdwell Construction-Sludge Stabilization

PHELPS DODGE REFINING COMPANY
EL PASO, TEXAS

BIRDWELL was contracted to complete a risk-based closure of 14 ponds for a metals refinery. Closure required the stabilization of 23,000 c.y. of pond sludge prior to removal. Eighty percent of the removed sludge was placed in an on-site landfill constructed as part of the contract. The sludge was stabilized with fly ash and tested prior to disposal or off- site resource recovery. The landfill cell, registered with the TNRCC, was constructed with the base stabilized with portland cement and placement of an HDPE liner. Once the landfill was filled, it was capped with a 40 mil. HDPE liner and soil cover.

The pond closure and landfill construction phase of the project was completed after BIRDWELL’s sister company constructed a wastewater treatment plant and 2 million- gallon concrete storage tank with a 100-mil HDPE liner. Once the wastewater treatment plant was brought on-line, BIRDWELL constructed two surge ponds (one totaled 5.5M gallons, the second 2.2M gallons). The ponds were constructed in the same manner as the landfill. Because of BIRDWELL’s performance at the site, Phelps Dodge requested that we complete a second project on a time and materials basis. The project required the demolition of two furnaces, two boilers, two stacks, and ancillary air emission control equipment. To complete this project, BIRDWELL collected by scrapping all recoverable deposits of copper.

Once this was done, dust was collected utilizing a guzzler with a hepa filter. The dust and copper scrapings were recovered by the owner. Refractory brick were then demolished and crushed. During the crushing process, a stabilizing agent was applied to stabilized lead, chromium, and arsenic. The brick was then loaded into gondola cars for transport and disposal. Stacks were demolished by hand. Cable climber scaffold were used to lower the demo crew down the stacks.