NHDES Updates to Env-A 1400 Rule: Regulated Toxic Air Pollutants

The New Hampshire Department of Environmental Services (NHDES) recently updated the Administrative Rule Env-A 1400: Regulated Toxic Air Pollutants (RTAPs). The rule sets ambient air limits (AALs) on listed RTAPs that are emitted into the atmosphere.  The listed chemicals have the potential to cause damage to human health and the environment.  

There are many types of pollutants on the RTAP list; some well-known chemicals are acetone, isopropyl alcohol (IPA), ethanol, methanol, methylene chloride, and acetic acid. Many biotech and pharmaceutical facilities use these chemicals for surface disinfection or in their manufacturing processes. Other industrial facilities such as ink manufacturers and semiconductor operations utilize RTAP-containing chemicals to make product.  

The rule requires facilities in New Hampshire to evaluate their emissions of RTAPs using one of the required methodologies in the regulation any time the NHDES revises the list of RTAPs, their respective AALs, or the compliance boundary in accordance with Env-A 1404.07(b) or (c). The most recent changes were adopted on February 3, 2022. Applicable facilities will need to show compliance within 90 days of the revision to the list (by May 3, 2022).  

Facilities located in New Hampshire should compile a list of all the chemicals used onsite and extract chemical constituent information using Safety Data Sheets (SDSs). Constituents used in a given year can then be evaluated to determine the applicability of the Env-A 1400 regulation. Any facility subject to Env-A 1400, must utilize a method listed in the Rule to demonstrate compliance with the limits. Common methods of demonstration include air dispersion modeling, de minimis emission evaluation or determining direct in-stack concentrations. Applicable sources must keep records onsite that compliance has been achieved. If compliance cannot be demonstrated, then the facility is required by the regulation to submit a permit application and compliance plan to NHDES. The facility must achieve compliance with the applicable provisions of the regulation by implementing remedial actions within 3 years of the published revisions to the RTAP list. 

Many of the changes that are part of the recent revision to the RTAP list are due to chemical compound categories such as stearates or heavy metal compounds that are broken down into common listed individual chemicals with specific CAS numbers. There have been more than 100 new CAS number listings added and more than 30 removed. There have also been numerous updates to individual chemical AALs. 

If you operate an Env-A 1400 applicable source or need help to determine whether Env-A 1400 is applicable to your operations, Capaccio Environmental Engineering has the experience and technical resources to bring your facility into compliance with the new RTAP list. Contact us to start discussing an evaluation of your process. The full amendment and list of RTAPs can be found on the NHDES website, or through the link below.