Washington Administrative Code › Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508) › Chapter 173-420 - Conformity of transportation activities to air quality implementation plans › Section 173-420-070 - Air quality analysis procedures

Current through Register Vol. 24-14, July 15, 2024
(1) Air quality analysis for transportation
			 plans, programs, and projects shall be modeled for criteria pollutants using
			 EPA and the federal Department of Transportation approved methods.
(2) Air quality analysis procedures and
			 methodology used in determining conformity for transportation plans and
			 improvement programs shall be determined through consultation with the MPO, the
			 United States Department of Transportation and the Environmental Protection
			 Agency, the state departments of ecology and transportation, the local air
			 authority, and other interested representatives of the public. The consultation
			 procedure for SIP and maintenance plan development in the applicable SIP shall
			 be used for the consultation process required by this section. The consultation
			 process shall also be used for determining research and data collection
			 efforts, and regional transportation model development, events that will
			 trigger new conformity determinations, the status of TCMs, significant changes
			 in project design and scope, and projects which require PM10 analysis. The
			 specific analysis procedures and methodology selected shall comply with this
			 chapter, the federal transportation conformity regulation ( 40 C.F.R. Part 51
			  Subpart T), and the applicable SIP. Agreement on the methods and assumptions
			 including modeling parameters, model accuracy, and the base year against which
			 alternatives are compared, shall be reached on all programs and plans prior to
			 the conformity determination. Procedures, methodologies, and input parameters
			 shall be reviewed and updated at least once every two years under the direction
			 of the departments of ecology and transportation. Such review shall occur prior
			 to conformity determination of transportation plan or TIP revisions.
(3) Procedures, methodologies, and
			 assumptions for project analysis shall be consistent with those procedures,
			 methodologies, and assumptions developed for analysis of transportation plans
			 and improvement programs in subsection (2) of this section.
(4) Each MPO shall conduct conformity
			 analyses of the transportation plan and improvement program developed in its
			 region.
(5) The lead agency shall
			 be responsible for project conformity analysis.
(6) The impact of preferred alternative
			 transportation plans, improvement programs, and projects shall be quantified
			 and compared for compliance to the SIP requirements, and the requirements of
			 WAC 173-420-060, and
			 173-420-065. If modeling does not
			 indicate that the requirements of this section are met, mitigating measures
			 shall be required and the plan, improvement program, or project remodeled. All
			 else being equal, the alternative with the lowest concentration shall be chosen
			 over all other alternatives.
Statutory Authority:
				  Chapter
				  70.94 RCW and  40 C.F.R.
				  Part 51  Subpart T. 95-18-022 (Order 94-31), § 173-420-070, filed 8/25/95,
				  effective 9/25/95. Statutory Authority:
				  Chapter
				  70.94 RCW and
				  RCW
				     70.94.037. 93-04-006 (Order 92-07), §
				  173-420-070, filed 1/22/93, effective
				  2/22/93.