Ashworth Leininger Group's litigation support practice leverages our demonstrated technical expertise in environmental compliance and permitting matters. ALG’s principals have been admitted as expert witnesses and supported legal counsel in a variety of complex litigation matters over alleged violations of the federal Clean Air Act and California Clean Air Act. Our specific expertise includes:

  • New and modified industrial source compliance with the U.S. Environmental Protection Agency (EPA) preconstruction approval programs: New Source Review (NSR) and Prevention of Significant Deterioration (PSD) programs
  • Compliance with the EPA Benzene Waste NESHAPS at chemical plants and industrial sources
  • Ambient impacts of industrial sources (stationary and mobile) on nearby residents and receptors posed by emissions from combustion and fugitive sources
  • Incremental cancer risks posed by diesel particulate emissions from mobile and stationary sources
  • Industrial source compliance with applicable federal and state air quality regulations
  • Compliance with EPA and California Air Resources Board fleet regulations

ALG routinely supports legal counsel in resolution of EPA, state, and local agency enforcement matters. This work typically includes focused technical analyses of historic activities and emissions, engineering studies relative to control requirements (LAER, BACT, BARCT, RACT and MACT/NESHAP), ambient air quality/health risk analyses as necessary to confirm potential impacts, and compliance analyses relative to applicable requirements. ALG staff has participated as technical experts at scores of administrative proceedings before state and local environmental hearing boards.

Health Risk Assessments

Ashworth Leininger Group’s health risk assessment (HRA) practice leverages our expertise in air toxics emissions inventory development, best available control technology for toxics (T-BACT) determination, and air dispersion modeling on behalf of industrial and regulatory clients. As illustrated below, ALG has the capabilities to:

  • Develop defensible toxic air contaminant (TAC) emission inventories under the California Air Toxics Hot Spots Program (AB 2588);
  • Use Geographic Information System (GIS) to develop key input data for HRAs;
  • Perform air dispersion modeling consistent with EPA, ARB, and local air district modeling guidelines;
  • Execute health risk assessment models that use the source emission rates developed in the emission inventory task and the output of the air dispersion modeling to quantify potential health effects;
  • Prepare comprehensive HRA reports; and
  • If necessary, provide assistance in making T-BACT determinations and developing Risk Reduction Plans.

For more information on ALG's HRA services please refer to our HRA brochure.

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Hazardous Material Consulting Agency


"Seasoned, experienced and personable with industry smarts, the whole ALG crew are THE "go to" air quality experts for all my industrial clients in California. Time and again, they have provided the technical underpinnings so necessary to "win the day" at air quality hearings, rule makings and enforcement proceedings."
- Environmental Lawyer, Los Angeles


Environmental Litigations Services


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For more information about our Expert Witness and Litigation Support services, please call or email us.

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