Air operating permit for large sources of air pollution
Commercial and industrial businesses that emit large amounts of air pollution must get an air operating permit. An air operating permit is a master document that lists all of the air pollution requirements that apply to a business or industry. Ecology and other clean air agencies in Washington issue these permits.
Apply for an air operating permit
A business must turn in an air operating permit application 12 months before the business has the potential to emit:
- More than 100 tons per year of any air pollutant.
- More than 10 tons per year of any hazardous air pollutant.
- More than 25 tons per year of a combination of hazardous air pollutants.
Even if a business emits less than these amounts, EPA may decide that it still needs an air operating permit. The federal rules that might apply include:
- Title IV Acid Rain Program
- New Source Performance Standards (NSPS)
- National Emission Standards for Hazardous Air Pollutants (NESHAP)
An air operating permit is valid for 5 years. A business must apply for renewal 6–18 months before the current permit expires.
Agencies that issue air operating permits include:
- Ecology Air Quality Program in Central Regional Office
- Ecology Air Quality Program in Eastern Regional Office
- Ecology Industrial Section – metal smelters and pulp and paper mills
- Ecology Nuclear Waste Program – Hanford
- Energy Facility Site Evaluation Council (EFSEC) – stationary thermal power plants with generating capacity of 350,000 kilowatts or more
- EPA – tribal lands
- Local clean air agencies
Twice a month, we publish a Permit Register that lists milestones for air operating permits.
Review a draft air operating permit
Check for a public comment period and review a draft air operating permit:
- Go to Public input and events
- Type "air operating permit" in the search box
Every two years, we prepare a workload model and a budget projection that evaluates the cost of reviewing, tracking, and overseeing air operating permits. After the public comment period, we finalize the workload analysis and budget. The most recent reports:
- Air Operating Permit Workload Analysis and Budget for fiscal years 2024 and 2025
- Air Operating Permit Workload Analysis and Budget for fiscal years 2022 and 2023
- Air Operating Permit Workload Analysis and Budget for fiscal years 2020 and 2021
At the end of each fiscal year (July 1 – June 30), we prepare an annual report summarizing air operating permit program work and fees.
We publish the current fiscal year’s fee schedule every year by October 31. If our costs were less than expected in the previous fiscal year, businesses are given a rebate toward their next year's fee.
Ecology and outside agencies regularly audit the air operating permit program.
- Fiscal audit — Every two years, the Washington State Auditor’s Office conducts a fiscal audit of Ecology’s and each local clean air agency’s air operating permit program.
- Performance audit — Every three years, Ecology and local clean air agencies conduct a routine overview performance audit.
- EPA audits — Periodically, EPA also reviews the air operating permit program and enforcement program.