The Casmalia Resources Superfund Site topped U.S. Environmental Protection Agency (EPA) Administrator Scott Pruitt’s April 16 emphasis list out of all other similar superfund sites. The agency released the list with a note explaining that it represented sites identified and targeted by the EPA for “immediate and intense attention.”
Casmalia in particular was chosen to help spur action for its upcoming cleanup and redevelopment efforts.
“We are making tremendous progress expediting sites through the entire superfund remediation process,” Pruitt said in a statement. “The updated emphasis list reflects our commitment to addressing superfund sites as quickly and safely as possible.”
The Casmalia site is a 252-acre former commercial hazardous waste management facility located 4 miles from the Pacific Ocean, and 10 miles from Santa Maria and Orcutt. Between 1973 and 1989, it accepted around 5.6 billion pounds of waste from more than 10,000 generators.
Operations at the site contaminated soil, air, surface water, and groundwater on the property with myriad types of mixed hazardous chemicals.
“If you can imagine 30 truckloads a day going back and forth to the site over a period of about 16 years, that was about our rough calculation [of how much waste was disposed of at the site],” said Russell Mechem, the U.S. Environmental Protection Agency’s (EPA) remedial project manager for the site. “We have many former waste management units … we call them ‘pits, ponds, and lagoons’—anything that was used to store different types of waste.”
The Casmalia facility accepted a wide range of solid and liquid hazardous waste materials during its operation, ranging from petroleum, acids, bases, organic chemical solvents, petroleum solvents, paint sludge, pesticides, infectious wastes, septic tank pumping, and sewage sludge.
In fact, the types and varieties of waste number so high and are so diverse that experts have trouble sharing a definitive list outlining them all.
“People sometimes ask for a list of the chemicals that were disposed at this site, and one possible response would be, ‘Well, give us a list of the chemicals that were not disposed at the site,'” Mechem said.
And some of those chemicals became something far worse than the sum of their parts when they blended together. One example is referred to by scientists as “DNAPL,” or dense nonaqueous phase liquids.
“When they did chemical analysis of it they identified 100 separate chemicals—one very long list of individual compounds,” Mechem said. Researchers found the material was heavier than water and noted in their reports that it tended to sink.
“What happened [at the site] is that [the DNAPL] tends to sink to the bottom of the landfills and accumulate along the base, and if there are fractures in the material, the compound can move into fractures,” Mechem said. “It’s complicated to work with.”
The EPA estimates that there could be as many as 100,000 gallons of DNAPL settled into the bottom of Casmalia’s many ponds, pits, and lagoons. Agency officials say they hoped to extract the liquid in the coming years but admit that they will never be able to remove all of the sludge-like material.
The agency stated on April 16 it hoped “to finalize a comprehensive cleanup plan and record of decision which includes: contaminated hotspot removal; engineered capping systems; groundwater collection and treatment systems; natural breakdown of groundwater contaminants at some locations; long-term surface water management; source reduction; land use controls; and ongoing monitoring and maintenance to ensure onsite containment. The proposed cleanup plan construction projects are estimated to take around five years to finish.
The initial emphasis list released by the EPA on Dec. 8, 2017, consists of 21 sites across the country and is considered a direct response to the Superfund Task Force Recommendations. The task force’s goals include: expediting cleanup; reinvigorating such efforts from responsible parties; encourage private investment to facilitate cleanup; promoting redevelopment and community revitalization; and engaging with partners and stakeholders.
The agency stated it “is anticipated that” the emphasis list “will be revised quarterly.”
This article appears in Apr 19-26, 2018.