SEPA checklist guidance, Section B: Air

We provide guidance to help applicants complete the Air section of the SEPA Section B: Environmental elements checklist.

2. Air

 a. What types of emissions to the air would result from the proposal during construction, operation, and maintenance when the project is completed? If any, generally describe and give approximate quantities if known:

This question refers to any type of air pollutant. It is not limited to dust, automobile, odors, or industrial wood smoke. The quantity and duration of emissions during construction, operation, and demolition are important. Activities that generate or have the potential to produce either indoor or outdoor air pollution emissions or odors include:
  • Abrasive blasting
  • Agricultural / residential waste burning
  • Asphalt preparation
  • Chemical spraying 
  • Coffee roasting
  • Composting
  • Concrete batching
  • Dry cleaners
  • Fuel dispensing or storage
  • Landfill Manure application and storage
  • Painting or surface coating
  • Planting / anodizing
  • Printing
  • Rock or material crushing, grinding, or transport
  • Soil or groundwater remediation
  • Solvent and other volatile liquid use or storage
  • Sterilization processes
  • Welding
  • Wood processing
Dust should be considered a potential air emission if upland vegetation will be removed as well as during grading, fill, excavation, rock crushing, and demolition activities.

Greenhouse gas emissions are considered an air pollutant and may need be addressed. If the amount of emission cannot be quantified, describe the source(s) including known or assumed quantities. For example: "Liquid manure from X number of dairy cows will be sprayed on X acres from May through September. The material will be collected on-site in an X-gallon capacity dairy lagoon."  It is probably wise to check any estimates against existing data.
b. Are there any off-site sources of emissions or odor that may affect your proposal?

Identify any regional air quality limitations such as an area designated to be out of attainment with state and federal air quality standards. For more information, contact your local air quality authority or our air quality staff.  Areas with existing air quality issues including smoke and other particulate matter, ozone, carbon monoxide, and odors, are more sensitive which could adversely impact some project activities.
c. Proposed measures to reduce or control emissions or other impacts to air, if any:

Describe management practices to be used to reduce or eliminate dust and other air emissions. These should include methods to contain, treat, or reduce odors or pollutant emissions such as:

  • Covering materials.
  • Covering or aerating wastewater lagoons.
  • Bag houses or air scrubbers.
  • Watering or stabilizing disturbed soils.
  • Using clean fuel / power.
  • Recycling solid waste rather than burning it or putting in a landfill.
Mitigation could also include watering roads, incorporating a mister into the crusher, lignin sulfate or other dust palliatives, and watering stockpiles.