The South Coast Air Quality Management District, one of a number of agencies that has oversight for Chiquita Canyon Landfill, announced Tuesday it filed a petition for an Order for Abatement that would require the facility to take actions to reduce odors impacting the community. The agency also discussed the status of the landfill’s efforts to apply for a new flare for its gas-to-energy plant.
L.A. County Public Health officials discussed strategies Monday evening for Castaic and Val Verde residents to lessen the effects from their exposure to the smell from increased levels of dimethyl sulfide, or DMS, at Chiquita Canyon.
Public Health reported the agency has urged the landfill to take “immediate actions to identify the cause and mitigate the impact of odors,” and shared the list of recommended actions for the landfill as well as actions that can help residents, too.
Steve Cassulo, district manager for Chiquita Canyon Landfill, tried to explain to residents Thursday in a Zoom call there are “a lot of moving parts” and he hoped to have temporary measures in place within about a month, but a more permanent fix could take longer.
“In May, South Coast AQMD began receiving hundreds of odor complaints that agency investigators traced back to the landfill,” the agency noted in a news release Tuesday. “As a result of its investigation, South Coast AQMD found that the landfill was experiencing elevated levels of sulfur, specifically dimethyl sulfide, in its landfill gas — which its gas treatment system is not designed to remove. The underlying cause has been found to be caused by a subsurface chemical reaction.”
The air regulator filed its petition with the South Coast AQMD Hearing Board, according to the release. “The Hearing Board is an independent panel that hears all sides of a case, weighs the evidence and reaches a decision,” according to the AQMD. “Actions requested by South Coast AQMD may be modified based on the Hearing Board.”
Health concerns
While residents have already started reporting short-term health impacts such as headaches, nausea and dizziness — which would be in line with someone who had prolonged exposure to a smelly sulfide-based compound — the county has reported as of now there’s no indication of any gases that have long-term health concerns, and current information indicates DMS is not a carcinogen.
“In terms of what we know about the landfill gasses, Chiquita Landfill, through their consultant SCS Engineers, has off-site continuous monitors for hydrogen sulfide (H2S) and particulate matter (PM2.5 and PM10), along with weather info,” according to an email sent Monday by Becky Schlikerman Sernik, director of external communications for the Department of Public Health. “In addition to the continuous monitors, they collect a monthly sample at three offsite and two onsite locations for some common volatile organic compounds (VOCs). According to the data provided by SCS, the concentrations of these substances that have been measured are lower than those that would be likely to cause long-term health effects.”
However, in the same email, the county notes the landfill has acknowledged the limitations in its current testing, which the landfill’s manager also mentioned last week, and DPH also asked the landfill to “evaluate the long and short-term health and environmental impacts of the current odor problem” and “determine potential health impacts from these landfill gases.”
The issue began earlier this year, and to date, Chiquita Canyon Landfill, a Waste Connections facility in Castaic, has yet to figure out how to stem the scent that’s unsurprisingly been compared to rotting garbage, which has become increasingly worse over the course of this year based on a growing number of complaints and an expanding area where the smell is being reported.
During the company’s first address of the public over the issue, Cassulo attributed the problem to the regular collection of landfill gasses that occurs through a landfill’s operation over time that has increased at a rate higher than landfill officials anticipated. He said the landfill’s previous operators did not take adequate measures to address the collection and decomposition of garbage from prior decades.
The landfill’s best guess for what’s going on, to date, is that the production of the stinky byproduct, DMS, occurred at a rate that exceeded the capability of equipment they have to help capture the gases.
The result has been a growing odor nuisance that’s drawn nearly 1,100 complaints since Jan. 1, and just over 220 in the first nine days of August. Every six substantiated complaints in a day will draw a notice of violation. The landfill recently hit 40 violations this year.
Schlikerman Sernik wrote that Public Health also called on the landfill to expand its testing capability.
“Among the recommended actions are: Expand the current landfill air-monitoring program to include other landfill gases, including but not limited to dimethyl sulfide; enhance and expand its current ambient air sampling program for chemicals in landfill gas; conduct frequent and additional odor sampling and sampling for volatile organic compounds, also known as VOCs, at residential locations where recent odor complaints have been reported; hire a consultant to work with Chiquita Canyon’s Technical Advisory Committee to evaluate the long and short-term health and environmental impacts of the current odor problem; report to the county the results if this increased monitoring and testing to determine potential health impacts from these landfill gases.”
Flare capacity
While the landfill is seeking to mitigate its smell, it’s also looking for permission to operate a new flare that would expand the operation of its gas-to-energy plant run by Ameresco at the facility.
Cassulo said the flare is part of a routine application and hopes the process will go quickly. AQMD officials said it’s unclear how the flare will assist in addressing the odor, according to an email Friday.
“The new flare was not originally submitted to address the current situation for increased dimethyl sulfide emissions but was part of the landfill’s ongoing regulatory requirements to collect and control landfill gas,” according to an email Monday from Nahal Mogharabi, assistant deputy of communications for the South Coast AQMD.
“It is unclear if the additional flare will remedy the current situation, but the flare will be utilized as part of the landfill’s strategy to mitigate the increased emissions,” Mogharabi added.
He also wrote Friday the agency would try to expedite the processing of the permit by prioritizing the address of any comments from residents.
“South Coast AQMD is currently awaiting verification that the public notice period has been initiated by Chiquita Canyon. Timelines are dependent on the level of public participation during the public comment period since South Coast AQMD is required to respond to all public comments received, in addition to any comments received from U.S. EPA.”
The air agency reported it’s been taking action at the facility to reduce odors “for many years,” via email.
“In addition to responding to thousands of odor complaints, and issuing dozens of violations, South Coast AQMD issued an Order for Abatement in 2020 that ended in 2022. The order requested studies and analyses that identified and implemented odor-mitigation approaches, which resulted in a decrease of odor complaints,” Mogharabi wrote. “The recent increase in odor events and sulfur emissions in 2023 has been determined by the landfill to be an ongoing subsurface chemical reaction. Chiquita Canyon continues to work with the County of Los Angeles as well as public health officials to investigate the ultimate root cause of the subsurface reaction as well as additional mitigation measures to reduce the emissions.”
Following the 6 p.m. Tuesday meeting at the Castaic Library (27971 Sloan Canyon Road) for the Chiquita Canyon Landfill Community Advisory Committee, Cassulo, as well as the landfill’s regulators, also are expected to be on hand 6 p.m. Wednesday for a virtual discussion led by the Castaic Area Town Council.
The link for the Town Council discussion is available at castaictowncouncil.org.
