US EPA’s New AERMOD Version 22112 and its Potential Impact on Ontario’s Regulatory Dispersion Model Version

The United States Environmental Protection Agency (EPA) released new versions (22112) of the AERMOD dispersion model and the AERMET preprocessor on June 27, 2022. The EPA invited industry and consultants to join the 2022 Virtual EPA Regional/State/Local Dispersion Modelers' Workshop to introduce the latest updates. This blog provides information on the background, release updates, future development plan and potential impact on Ontario’s regulatory dispersion model versions.

Background

In 2005, the American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was promulgated as the EPA’s preferred near-field dispersion model for regulatory applications, replacing the Industrial Source Complex (ISC) model. There were a variety of regulatory formulation and related implementation updates to the AERMOD Modeling System in 2017. AERMOD was designed to accept more robust meteorological data, including multi-level profiles of wind, temperature, and turbulence to simulate the atmospheric boundary layer more accurately.

In accordance with the Ontario Regulation 419/05: Air Pollution – Local Air Quality (“the Regulation”) and Ontario Guideline A-11, facilities may only choose between SCREEN3 and AERMOD to assess compliance with the air standards in Schedule 3. Use of SCREEN3 is considered to represent a conservative Tier 1 screening type of modelling assessment while the use of AERMOD represents a more comprehensive approach and is categorized as either a Tier 2 or Tier 3 type of assessment. As noted in the Regulation, the regulatory version of AERMOD model may be amended from time to time. This means that there is a specific version of each of these models that is considered to be an “approved dispersion model.” Currently, the Ontario Ministry of the Environment, Conservation and Parks (MECP) adopts the 2019 AERMOD version 19191 and AERMET version 19191. MECP’s next window to provide pre-notification of updates to the Ontario regulatory AERMOD version is October 1, 2022.

AERMOD Version 22112 Updates

AERMOD Version 22112 updates include code maintenance, general bug fixes for tall stacks, buoyline sources, and the urban dispersion option. The new “experimental” ALPHA options include NO2 conversion methods, low wind handling, “sidewash” point source (developed by Cornell University),and platform downwash for offshore sources. Other model updates in a BETA peer review phase include R-line for refined transportation projects and the non-regulatory Generic Reaction Set Method (GRSM) for NO2 conversion, which are potentially ready for consideration as regulatory options. AERMET version 21112 is re-configured to eliminate stage 2 (merge stage), which simplify the process to generate the AERMOD ready met data.

Future Development Plan

Model formulation updates to the AERMOD Modeling System last occurred in 2017 when EPA finalized updates to the Guideline on Air Quality Models. EPA is planning to propose an update to the Guideline in 2023. The formulation updates are developed and implemented through model development, model evaluation and model review & application. The current improvement priorities for the regulatory release include:

• Overwater Modeling–Refine / evaluate the platform downwash algorithm and add shoreline fumigation capability to AERMOD

• NO2 Conversion –Testing of GRSM and TTRM/TTRM2 as the more advanced conversion options

• Mobile Source Modeling / RLINE–Push from BETA to regulatory, improve treatment of terrain, and edge effects within the barrier algorithm

• Low Wind –Evaluate current low wind options against field dataset

• Urban meteorology –Improve inputs and processing for the URBAN option

Potential Impact on Ontario Regulatory Version

ORTECH is of the opinion that the changes in the version 22112 are minor and therefore the likelihood for Ontario MECP to adopt this version is low. This combined with US EPA’s proposed 2023 updates, including formula updates, would potentially represent a major upgrade to the AERMOD model. If the 2023 improvement priorities for regulatory updates are completed, MECP may consider adopting the 2023 updated versions. Under current MECP policy a six-month pre-notification period will be provided, prior to officially adopting a new regulatory version of AERMOD.

ORTECH has been conducting air quality assessments for over 40 years and continues to monitor developments in dispersion modelling and how these may impact our industrial and other clients. Please contact Leo Sun at lsun@ortech.ca for more information.

Does Your Cannabis Extraction Operation need to Register in the Environmental Activity Sector Registry ("EASR")?

Photo by Demi Pradolin on Unsplash

For more information on this article please contact info@ortech.ca.

Ontario’s Regulation 1/17 requires persons engaging in activities that discharge (or may discharge) contaminants to the air, to register in the Environmental Activity Sector Registry (“EASR”), unless the activities do not meet the criteria in the Regulation.  To answer the title of this piece, yes, the Ministry of Environment, Conservation and Parks (“MECP”) will require Cannabis Extraction operations to be registered in the province’s Environmental Activity and Sector Registry ("EASR"). 

 This registry applies to all facilities which are not specifically excluded in the regulation (https://www.ontario.ca/laws/regulation/170001) either due to their primary activity code (NAICS code) or their specified activities.  For those more familiar with the Environmental Compliance Approval (“ECA”) process, the requirements for the Air Emissions EASR process differ from the ECA process in that review and approval from the MECP is not required (see ORTECH’s blog here for further explanation).

 Under the EASR process, Facilities are required to submit an application and maintain documents and records, but approval and authorization is essentially granted upon registration.  This allows Facilities to implement changes to operations or start construction on new equipment installations without regulatory delay.  This self-permitting approach is meant to improve the time it takes for industry to obtain air and noise permits.

 My extraction method does not produce any air emissions.  Do I still require an EASR?

 Yes, a registration is still required. 

 Odour control, and more specifically air emissions/Volatile Organic Compounds (“VOC”) control, is expected to be needed for both a solvent-based and solvent-free cannabis extraction process.  A solvent based process will have some VOC air emissions, which may or may not be odorous.  In fact, even highly efficient solvent-based processes can lose 4 – 6 % of their solvent during the extraction process.  The current regulations consider all these loses to be airborne, thus the need for the EASR. 

 The super-critical CO2 extraction method, which is solvent-free, does not emit contaminants directly. However, processes called Winterization and Distillation follow similar methods as CO2 extraction where contaminants/odour are released, requiring an EASR.  CO2 extraction is also highly energy intensive, so other contaminants like nitrogen oxides (“NOx”) from fuel burning need to be considered.  In addition, it is a requirement to assess potential noise impacts as part of the EASR process.

 When do I need to do this?

 As of December 31, 2016, if you made or make changes to your emission related operations, or if you install new equipment that have emissions, you must determine if your facility is required to register for an EASR.

 What are the requirements for the EASR process?

1. Assess all emissions from the facility for comparison with MECP limits.

2. Assess all substances that have no MECP limits.

3. Assess noise and odour emissions.

4. Develop and implement noise and odour mitigation control plans (i.e. odour control reports), if required.

5. Develop maintenance and operational procedures, complaints and record management requirements.

How can ORTECH help?

ORTECH has been involved in environmental permitting and odour assessments for over forty years and is experienced in the operation and performance of air pollution control equipment for many different NAICS code operations.  Experience which ORTECH can provide for the preparation of Odour Screening Reports, Best Management Practice Plan (“BMPP”) Reports and Odour Control Reports includes:

• Odour emission testing at point, area and fugitive sources in many types of NAICS code facilities.

• Odour performance evaluation of odour control equipment, such as biofilters, adsorbents, wet scrubbers, ozonation systems and ultra-violet devices.

• Emission testing for odourous compound emissions including aldehydes amines, ammonia, carboxylic acid, hydrocarbons, ketones, reduced sulphur compounds and volatile organic compounds such as terpenes.

• Determination of odour threshold values for specific odourous compounds which have no published values.

• Effects of processes and process changes on odour emissions.

• Atmospheric dispersion modelling for odours and odourous compounds.

• Community odour surveys and assessment of odour complaints.

• Preparation of odour testing reports, Emission Survey and Dispersion Modelling (“ESDM”) reports, ECA applications and EASR applications.

ORTECH is also experienced at providing odour expert witness testimony at trials, hearings and tribunals.

For more information on this article please contact info@ortech.ca.

Does my Municipal Building Need an Environmental Approval (ECA or EASR)?

By: Giulia Celli

The answer to this question depends on several factors such as the equipment you have installed, the location of the equipment and the potential for any environmental impacts.  Let’s back up and provide a bit of context.  The Ontario Government’s environmental rules say that if your business emits any contaminants to the air, you must comply with the regulation however, there are exemptions to this rule.  Section 9 (3) of the Ontario Environmental Protection Act, R. S. O. 1990, (the EPA) and O. Reg. 524/98 specify the (limited) types of equipment, activities, and operations that are exempt from needing an Environmental Compliance Approval (ECA) or an Environmental Activity and Sector Registry (EASR) registration. These exemptions include low capacity natural gas comfort heating systems, and standby power systems. Systems that you would generally find in a municipal building.

For example, an HVAC system that meets the following criteria is likely to be exempt:

·         Each combustion unit uses only natural gas, propane or both natural gas and propane as fuel, and

·         The thermal input rating of each combustion unit is not greater than 10.5 million kilojoules per hour.

·         If the HVAC system includes a cooling tower, drift loss from the cooling tower is controlled by drift eliminators.

And a standby power system that meets the following criteria is likely to be exempt:

·         The system is used and operated only during power outages or for testing or performing maintenance on the system;

·         The standby power system uses only one or more of the following as fuel: biodiesel, diesel, natural gas, and propane;

·         Each exhaust stack that is part of the standby power system is oriented vertically (and not obstructed by a rain cap);

·         Each generation unit that is part of the standby power system and that uses diesel or biodiesel as fuel, must meet, at a minimum, the Tier 1 Emission Standards set out in Table 1 of 40 CFR 89.112 (United States)

·         Each generation unit that is part of the standby power system and that uses propane or natural gas as fuel, must have a maximum discharge of 9.2 grams of nitrogen oxides per kilowatt hour

Other exemptions include things such as equipment used for food and beverage preparation at retail locations, items associated with low occupancy dwellings, some mobile equipment, and more. To complicate matters, the equipment may be exempt from requiring a permit but the facility itself is still required to meet this standard from the EPA:

“…despite any other provision of this Act or the regulations, a person shall not discharge a contaminant or cause or permit the discharge of a contaminant into the natural environment, if the discharge causes or may cause an adverse effect.” 

For municipal operations in multi-tenant buildings this general provision of the EPA can create some issues when air intakes are not sufficiently separated from equipment which would be otherwise exempt from obtaining an ECA or EASR permit.   

For due diligence, it is recommended to have all equipment that emits any contaminants (including noise and odour) to the air assessed for compliance. It is recommended that a letter from a qualified person stating that the facility is in compliance with Ontario regulations is kept with the facility.

If you have any questions about this post, please reach out to Giulia Celli at gcelli@ortech.ca.