Air Quality

The Kettleman Hills Facility has several different types of waste treatment, storage, and disposal units for both municipal solid waste and hazardous waste.  Although all the waste management units at the facility are strictly regulated by both the federal government and the state of California, following requirements that are designed to protect human health and the environment, these units, like those operated at other waste management facilities nationwide, have the potential to emit compounds present in materials received at the facility into the air.

Regulatory programs are in place at both the federal and state levels to minimize air emissions from waste management facilities, including the Kettleman Hills Facility.  The primary agency responsible for protection of air quality at the federal level is the U.S. Environmental Protection Agency (USEPA), which regulates air emissions and ambient air quality through the U.S. Clean Air Act.   At the state level, the primary regulatory agency is the California Air Resources Board (ARB), a branch of the California Environmental Protection Agency (Cal/EPA).  The ARB is responsible for implementing both the federal Clean Air Act and the California Clean Air Act.  In addition, the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD) is responsible for regulating air emission sources and achieving and maintaining air quality in the San Joaquin Valley.  The California Department of Toxic Substances Control (DTSC) also is active in the regulation of air emissions from waste management facilities.  All of these agencies are involved in regulating potential air emissions from the Kettleman Hills Facility and, in addition, USEPA, SJVUAPCD, and DTSC often conduct inspections of facility operations.

Over the past 20 years, extensive air monitoring studies and several health risk assessments have evaluated the potential impacts of air emissions from the Kettleman Hills Facility on air quality and public health.  These studies have evaluated potential impacts both in the immediate vicinity of the facility as well as in Kettleman City, which is located 3.5 miles to the northeast of the facility.  These investigations include monitoring of chemical concentrations in air using USEPA-approved sampling methods and also health risk assessments that follow USEPA and California guidance.  Together, these investigations provide a scientific database on air quality at the site and support a common conclusion:  the Kettleman Hills Facility does not adversely impact air quality or pose risks to residents in and around Kettleman City.  A brief summary of recent and historical studies related to air quality follows.

 Recent Studies

  • Ambient Air Monitoring Program.  Since 2006, an Ambient Air Monitoring Program (AAMP) has regularly collected air measurements at three sampling stations located around the Kettleman Hills Facility boundary.  This program was initiated at the request of DTSC in accordance with the facility’s permit under the U.S. Resource Conservation and Recovery Act (RCRA), the U.S. law that defines solid and hazardous wastes and sets up an overall U.S. waste management strategy.  More than 140 sampling events have been completed since this program began in 2006 and, over the past several years, detailed evaluations of these data have been conducted.  These evaluations demonstrate that the ambient air around the Kettleman Hills Facility is consistent with background regional air quality (that is, in the absence of the facility) and that the Kettleman Hills Facility does not measurably affect air quality in and around Kettleman City.  Cal/EPA also conducted an independent evaluation of air quality data collected both in Kettleman City and at the Kettleman Hills Facility.  Cal/EPA  concluded that it is unlikely that air compounds measured at the facility pose health risks to the residents of Kettleman City.
  • Human health risk assessments.  Several human health risk assessments have been conducted to evaluate potential air emissions from the Kettleman Hills Facility.   These studies included assessments of potential risks to human health that could result from the air transport of facility emissions to residential locations in and around Kettleman City.   Risks to residents were evaluated assuming that a person would be exposed for 24 hours per day, 350 days per year, for several decades.  All of the health risk assessments showed that facility emissions do not pose risks to residents in and around Kettleman City.  The risk assessment results were consistently many times lower than California and USEPA benchmark risk levels for both non-cancer and cancer health effects.  The studies also determined that potential risks in and around Kettleman City associated with facility emissions are at least 700 times lower than the background risks (in the absence of the facility).  Overall, the risk assessments demonstrate that potential air emissions from the Kettleman Hills Facility do not pose public health risks in neighboring residential communities.
  • PCB Congeners Study.  In the most extensive study of its kind ever conducted at a regulated waste treatment, storage and disposal facility in the U.S., Waste Management, at the direction of USEPA, examined the potential impacts associated with a class of compounds called polychlorinated biphenyls (PCBs).  Although the manufacture of PCBs was banned in 1979, they can still be found today in transformers and other electrical equipment, which may be received and processed at the PCB flushing/storage unit at the Kettleman Hills Facility.  This study measured the concentrations of selected PCB compounds (called congeners) in soil, air and vegetation at the perimeter of the Kettleman Hills Facility and, based on these data, calculated the potential human health and ecological risks that may be posed by the management, storage, and disposal of PCB wastes at the facility.  USEPA approved the study in 2010 and reached the following conclusions based on its results:
    • “There is no evidence suggesting that PCB congeners from operations at the CWM Facility are migrating off-site at concentrations that would adversely affect the health of local community residents or the environment.”
    • “Concentrations of PCB congeners measured in soil samples collected at the perimeter of the CWM Facility are 2,000 times below EPA’s risk-based residential clean-up levels.”
    • “Risk of health impacts from PCB congener concentrations measured in soils, vegetation, and air near the perimeter of the CWM Facility are in the same range as risk of health impacts in other rural areas without known PCB activities or sources.”
  • Cal/EPA Exposure Assessment.  In 2010, Cal/EPA conducted a major investigation of environmental exposures in Kettleman City.  Their study involved testing the area’s air, water and soil around agricultural operations, at the Kettleman Hills Facility, at several locations in Kettleman City, at locations of former industrial and commercial operations, and in the area of illegal dump sites around town.  Cal/EPA tested for numerous chemicals in the environment including pesticides, PCBs, dioxins and furans, metals and volatile organic compounds.  Cal/EPA examined several years of air monitoring data collected in the immediate vicinity of the Kettleman Hills Facility as part of the facility’s ambient air monitoring program.   The study also included a detailed evaluation of pesticide use in the Kettleman City vicinity.  With respect to the Kettleman Hills Facility, Cal/EPA concluded:  “Air tests found no link between the Kettleman Hills Hazardous Waste Facility and environmental contamination in the town.”  Cal/EPA also found that emissions originating from the Kettleman Hills Facility “as measured using fence-line monitoring were found not to affect the level of measured contaminants in the city.”  Cal/EPA did identify other potential sources of air quality concerns in Kettleman City not related to the Kettleman Hills Facility, including pesticides and benzene, which they are continuing to investigate.

Historical Studies

  • California Air Toxics Hot Spots Evaluation (1996).  In accordance with California’s “Air Toxics ‘Hot Spots’ Information and Assessment Act of 1987,” Waste Management evaluated potential air releases from the Kettleman Hills Facility according to a plan developed with SJVUAPCD.  In 1996, SJVUAPCD issued the Kettleman Hills Facility “Prioritization Score and Ranking”, where a score of less than 1 designates the facility as low priority, a score of 1 to 10 a medium priority, and a score above 10 as high priority.  The Kettleman Hills Facility received a score of 0.244, and a Prioritization Category of “Low.”
  • Air Monitoring Program (1986 – 1995).  This study, which was conducted at the request of the Kings County Planning Agency, evaluated the potential for off-site transport of volatile organic compounds (VOCs) emitted from the Kettleman Hills Facility by measuring VOCs in air at three stations located at the Kettleman Hills Facility, one station in Kettleman City and one station in Avenal.  Air samples were regularly collected at these five stations, producing a database of more than 15,000 measurements over the course of the study.  The monitoring program results showed that the Kettleman Hills Facility had no discernable impact on air quality in Kettleman City or Avenal.  In 1995, the Kings County Planning Agency determined that the facility had met its air monitoring requirements and approved discontinuation of the program.
  • 1994 Topographical, Meteorological and Airborne Contaminant Characterization at Kettleman Hills Facility (1995).  This study, conducted at the request of DTSC in accordance with DTSC and U.S. RCRA guidelines, evaluated air emissions from the Kettleman Hills Facility during 1994 and 1995.  The study involved collecting samples of air, soil, soil pore gas, and the solid and liquid waste materials within and in the immediate vicinity of potential emission locations at the facility.  This was done to identify and quantify hazardous constituents that might be emitted into the air from the facility, if any, and characterize the land and weather conditions that might affect their transport.  Based on analysis of the data collected, the study concluded that the potential impact to off-site receptors was not great enough to justify an ambient air monitoring system around the Kettleman Hills Facility.
  • Gaseous Tracer Study (1988).  Under the direction of the California Air Resources Board (ARB), a series of six atmospheric tracer tests were conducted at the Kettleman Hills Facility in 1988.  These tests, which were conducted under extreme “worst case” dispersion conditions, showed that winds blowing from the facility towards Kettleman City were rare and that air emissions from the facility were diluted as they move away from the facility as a result of both distance and land topography.
  • Air Quality Test Report (1988).  From August to September 1988, tests were conducted at the Kettleman Hills Facility to determine the composition of landfill gases, the presence of chemical compounds in the ambient air around the facility and whether off-site subsurface migration of landfill gas was occurring.  The study results showed that the Kettleman Hills Facility did not have an adverse effect on air quality surrounding the site and that measured air levels around the facility were generally similar to background air quality levels.