The other night, I woke up in a bit of a panic and thought that I must have missed an announcement by the USEPA regarding the PM2.5 NAAQS reconsideration! Did I?
The answer, thankfully, is no! However, that is not any reason to relax and take no action.
By way of background, the Clean Air Act requires that the USEPA set National Ambient Air Quality Standards (NAAQS) for each of the criteria air pollutants, including particulate matter (PM). These NAAQS are based on the best available science and aim to protect human health and welfare. In June of 2021, the USEPA announced that they would reconsider the 2020 PM NAAQS final action under the prior administration that did not lower any standards. Then, in January 2023, the USEPA published the proposed rule to revise the PM2.5 primary annual standard down from 12 micrograms per cubic meter (µg/m3) to within a range of 9-10 µg/m3. In that proposal, the agency retained the 24-hour standard of 35 µg/m3.
The comment period for this proposed rule has since closed, and the agency is now working through over 5,000 submitted comments. It is unclear when the USEPA will issue the final rule (it could be any day now) and if the new annual standard will be set at 9 or 10 or something in between.
What does this mean for me as a regulated source? What should you do? SCS Engineers recommends the following actions:
About the Author: Rafe Christopherson, PE, is a project director and SCS’s industrial Clean Air Act leader. He is an air quality professional with a wide variety of experience over his 25-year career. His expertise includes consulting, working at an air quality regulatory agency and with industry. His expertise includes semiconductors, biofuels, pulp and paper, hardwoods, power generation, refineries, and general manufacturing. If you are interested in more information on this PM2.5 NAAQS reconsideration process and what it might mean for your business, you may reach Rafe at or via LinkedIn.
Agricultural growing and harvesting operations are typically exempt from air planning, permitting and odor nuisance regulations. However, cannabis operations may require approval from the local Planning Commission. They may also require air permits from the local air regulatory agency for manufacturing operations (e.g., for solvents and associated combustion equipment such as boilers). Air permit applications for cannabis manufacturing operations may include the following based on project-specific conditions:
In addition to these permitting services, and to avoid costly nuisance complaints, cannabis growers may also need odor-related services such as:
While these may seem like imposing lists for air planning they are not for engineers who work in the industry.
Developing effective plans to mitigate odors is vital in gaining Planning Commission approvals which often depend upon resolving concerns raised by the public. Comprehensive OAPs and OMPs include odor control Best Management Practices (BMPs) and adaptive management strategies for responding to odor complaints when cannabis operations are near residences and schools.
Odor Control – Odor Nuisance Mitigation Case Study
Cannabis greenhouses in the Carpinteria, California region were causing off-site odor nuisances at nearby residences. The inherent smell needed addressing, as odor-neutralizing vapors along cannabis greenhouse perimeters and ridgelines were not providing adequate odor control.
Working with Cannabis Association for Responsible Producers (CARP) Growers, Pacific Stone, Groundswell, and Envinity Group, SCS Engineers utilized its air quality and odor expertise to collect continuous measurements using our SCSent-i-PED (Pollutant and Environmental Data). SCSent-i-PED is a state-of-the-art method for measuring TRS compounds to the parts per billion (ppb) level. The system can assess concentrations in real time, and a single machine can assess multiple locations and sources within a facility. This method successfully assessed relative odor levels and spatial/temporal fluctuations in odor-causing emissions.
Data collection is vital and useful to:
SCS, through its years of experience in air quality and odors, provides cost-effective, sustainable solutions that enable greenhouses and facilities to coexist in urban and suburban environments. Our clients not only get solutions, but they also have the data and science to understand better how odors behave and vary within a cannabis greenhouse.
To learn more, watch a video about air planning and managing greenhouse odors at https://www.scsengineers.com/services/clean-air-act-services/odor-monitoring-and-control/
About the Author: Paul Schafer is a Vice President and Project Director at SCS Engineers and the firm’s National Expert on Ambient Air Monitoring. During his technical career, Paul has assumed key roles in several nationally significant monitoring efforts. He has in-depth experience interfacing with regulatory agencies regarding the performance of monitoring systems, source emission tests, and continuous process monitors, which SCS operates for our clientele. He has had direct working experience with multiple local, state, and federal agencies regarding monitoring programs and air quality impact assessments. As with all solutions at SCS, cost control management and defensible technical performance are primary goals integral to all sustainable monitoring programs.
On March 1, 2021, the New Jersey Department of Environmental Protection (NJDEP) proposed several amendments to air quality regulations pertaining to the regulation of New Jersey Hazardous Air Pollutants (NJHAPs) as well as fumigation operations. The NJHAP regulations changes could significantly impact MSW landfills because they include proposed changes to hydrogen sulfide regulation as a NJHAP.
Key changes are summarized as follows:
Several potential implications could result from these proposed changes, including:
A virtual public hearing regarding the proposed changes is scheduled for April 8, 2021, at 4:00 PM (ET). A link to the virtual public hearing will be posted at http://www.state.nj.us/dep/aqm/curformp.html.
Written comments are due no later than April 30, 2021, to www.nj.gov/dep/rules/comments.
View the proposed changes may be viewed at https://www.nj.gov/dep/rules/proposals/20210301a.pdf
Please direct questions to your SCS Project Manager or one of our local professionals: