Unable to extinguish a smoldering chemical reaction that sent noxious odors into area neighborhoods and triggered legal action by Los Angeles County, the owners of Chiquita Canyon Landfill announced Tuesday that they would shutter the 52-year-old municipal waste site on New Year’s Day.

In a letter to California environmental regulators and public officials, a representative from Texas-based Waste Connections Inc. said that Dec. 31 was the final day it would accept solid waste at the 639-acre facility in the Santa Clarita Valley.

“Chiquita had wished to maintain its crucial role in the community’s solid waste management system, but has made the difficult decision to close its active waste disposal operations,” wrote Steve Cassulo, the landfill’s manager. “Although Chiquita has available (capacity), due to the regulatory environment, maintaining ongoing operations at Chiquita is no longer economically viable.”

For nearly two years, Chiquita Canyon had been struggling to handle the fallout from a rare chemical reaction that caused broiling temperatures to break out deep underground in a closed portion of the landfill. The extreme heat roasted decades-old garbage and damaged the landfill’s gas control systems, causing foul-smelling gases to drift into the nearby Val Verde and Castaic.

The smoldering conditions also caused pressure to build, resulting in geysers of hazardous liquid waste bursting onto the surface and white smoke seeping out of long fissures. In recent months, Chiquita Canyon has faced increasing pressure from regulators, who placed restrictions on where waste could be placed within the landfill.

Chiquita Canyon, Los Angeles County’s second-largest active landfill, typically accepted roughly 2 million tons of solid waste annually. That accounted for about one-third of all garbage disposed of in L.A. County.

In a region that has long struggled with waste reduction efforts and waning disposal capacity, public officials are now examining how the closure will affect the flow of waste in Southern California.

L.A. County Supervisor Kathryn Barger said public officials had anticipated Chiquita Canyon’s closure. The landfill had been accepting significantly less waste recently. L.A. County officials oversaw a diversion of this waste to Simi Valley and Antelope Valley landfills, Barger said.

So far, there has not been an increase in tonnage sent to Sylmar’s Sunshine Canyon, which accepts the most waste annually.

Barger said she would introduce a motion at the next Board of Supervisors meeting on Jan. 7, directing Public Works to conduct an assessment of Chiquita Canyon’s closure, including the environmental and financial implications associated with plans to send waste elsewhere.

“I’m committed to ensuring that this transition doesn’t lead to any form of price gouging or unfair practices in waste management services,” Barger said. “Protections must be in place to prevent increased financial burdens on our residents and businesses. I want to emphasize that my top priority, though, continues to be bringing relief to the community that continues being afflicted by the landfill’s noxious odors.”

L.A. County Public Works had previously expressed concerns about closing Chiquita Canyon.

A decision to close Chiquita Canyon was not expected to resolve the chemical reaction, which was occurring in the long-dormant section of the landfill and could persist for years. The agency noted also that the closure could result in more pollution and higher fees due to transporting garbage farther.

“As the agency responsible for regional waste planning in Los Angeles County, we will ensure there are no disruptions to trash collection services in our unincorporated communities and will work closely with the City of Santa Clarita to help prevent any disruptions to their services as well,” said Mark Pestrella, director of L.A. County Public Works. “The health and safety of our residents remains our top priority.”