Philadelphia Proposes Sweeping Revisions to 40-Year-Old Air Toxics Regulations to Require Health Risk Assessments for Virtually All Permit and License Applications and Renewals

Public Participation Period Ends June 1

May 10, 2022
Katherine L. Vaccaro, Esq. and Michael C. Nines, P.E., LEED AP
MGKF Special Alert

The City of Philadelphia Air Pollution Control Board (APCB) has approved a proposed rulemaking package from Air Management Services (AMS), an arm of the Philadelphia Department of Public Health (the “Department”), to substantially revise the existing Air Management Regulation VI Control of Emissions of Toxic Air Contaminants (the “AMRVI”).  The proposed regulatory package is available here (the “Proposed Rule”).  The only way to comment on the Proposed Rule is to file a request for a public hearing with the City’s Department of Records, attend the hearing, and read your comments aloud.  AMS is not accepting written comments.  AMS started the clock on the 30-day period during which a public hearing can be requested on May 2, even though they didn’t publicly notice the Proposed Rule until several days later.  This all means that if you have an interest in participating in the regulatory development process for the Proposed Rule, you must request a public hearing by June 1.  If no one requests a hearing, then the Proposed Rule will automatically become final and effective on June 1. 

If the Proposed Rule is finalized, anyone applying for any air permit or license, or any permit renewal required by the AMS code (with limited exceptions) – including Title V renewals – will be required to determine whether their facility has the potential to emit any one of the more than 200 listed air toxics in an amount above the applicable threshold.  If they do, then the applicant must conduct a health risk assessment using AMS’ “Risk Screening Workbook,” which is part of the proposed regulatory package.  The Department will then act on the application by either approving it as submitted, denying it, or approving it subject to whatever emission limits or other conditions the Department deems necessary to address the health risk posed by the air toxic(s).  Notably, the Proposed Rule requires the Department to review the existing air toxics concentrations surrounding the relevant emission sources prior to acting on the permit application.  So while the obligation to conduct a risk assessment would depend on the facility’s own potential emissions, the Department’s decision on the permit application would account for concentrations of air toxics in the area surrounding the facility and thus emissions generated by other emission sources.

Although the AMRVI hasn’t been updated in any material way since 1981, the Proposed Rule generally retains the same structure as the AMRVI. But if the AMRVI is Bruce Banner, then Proposed Rule is more like the Incredible Hulk.  In particular, the Proposed Rule would expand the list of covered air toxics to 217, up from 99 in the AMRVI.  More critically, where the AMRVI triggers health risk assessments based on generalized ambient concentrations of air toxics, the Proposed Rule would establish specific applicability thresholds using a new methodology based on defined cancer and non-cancer risk criteria.  As a result, the Proposed Rule would require a health risk assessment for most air toxics at maximum annual concentrations that are hundreds, even thousands, of times lower (i.e., more stringent) than under the AMRVI.  Examples of the proposed thresholds include: asbestos at 0.007 pounds/year, 1,2-dichloroethane at 2 pounds/year, benzene at 7 pounds/year, benzo(a)pyrene at 0.05 pounds/year, ethylene oxide at 0.01 pounds/year, lead and lead compounds at 2 pounds/year, naphthalene at 1.6 pounds/year, vinyl chloride at 6 pounds/year, and fumigants at 16 to 2,000 pounds/year).  Finally, while not spelled out in the proposed regulatory language, we anticipate AMS will also use the new risk assessment methodology in the enforcement context regardless of whether the affected facility is seeking any permit authorization.    

The proposed regulatory package published by AMS incorporates technical guidelines that would need to be followed in conducting the risk assessments.  One of these documents is the “Risk Screening Workbook,” but oddly, the most important part of the workbook, a working Excel spreadsheet, is missing from the proposed regulatory package.  Nevertheless, MGKF has been able to secure a copy of the spreadsheet and is in the process of evaluating it for accuracy and functionality.

The Proposed Rule largely mirrors the New Jersey Department of Environmental Protection (NJDEP) Air Quality Permitting Program’s own risk assessment procedures and screening tools to evaluate potential effects on public health from facilities seeking new, modified, and/or renewed permits to emit air toxics.  New Jersey’s approach to risk assessment is among the most stringent in the United States, although upon initial review, the draft risk screening tool in the Proposed Rule appears to include some inconsistencies as compared to New Jersey’s (namely short-term and long-term Toxicity Values for Inhalation Exposure for certain air toxics).  AMS developed the Proposed Air Toxics Regulation with input from the Clean Air Council and other public-interest groups who had been lobbying AMS for years to revamp the City’s approach to regulating air toxics.  Still, it would not be surprising to see one or more of these groups argue that the Proposed Rule is not stringent enough.

We will be watching the City’s docket closely for any requests for a public hearing on the Proposed Rule.  If you are interested in getting involved in the public participation process or would like additional information, please contact Kate Vaccaro or Mike Nines at MGKF (484-430-5700).