Utah Administrative Code

The Utah Administrative Code is the body of all effective administrative rules as compiled and organized by the Division of Administrative Rules (see Subsection 63G-3-102(5); see also Sections 63G-3-701 and 702).

NOTE: For a list of rules that have been made effective since January 1, 2020, please see the codification segue page.

NOTE TO RULEFILING AGENCIES: Use the RTF version for submitting rule changes.

R307. Environmental Quality, Air Quality.

Rule R307-421. Permits: PM10 Offset Requirements in Salt Lake County and Utah County.

As in effect on January 1, 2020

Table of Contents

R307-421-1. Purpose.

The purpose of R307-421 is to require emission reductions from existing sources to offset emission increases from new or modified sources of PM10 precursors in Salt Lake and Utah Counties. The emission offset will minimize growth of PM10 precursors to ensure that these areas will continue to maintain the PM10 and PM2.5 national ambient air quality standards.

R307-421-2. Applicability.

(1) This rule applies to new or modified sources of sulfur dioxide or oxides of nitrogen that are located in or impact Salt Lake County or Utah County.

(2) A new or modified source shall be considered to impact an area if the modeled impact is greater than 1.0 microgram/cubic meter for a one-year averaging period or 3.0 micrograms/cubic meter for a 24-hour averaging period for sulfur dioxide or nitrogen dioxide.

R307-421-3. Offset Requirements.

(1) The owner or operator of any new source that has the potential to emit, or any modified source that would increase sulfur dioxide or oxides of nitrogen in an amount equal to or greater than the levels in (a) and (b) below shall obtain an enforceable emission offset as defined in (a) and (b) below.

(a) For a total of 50 tons/year or greater, an emission offset of 1.2:1 of the emission increase is required.

(b) For a total of 25 tons/year or greater but less than 50 tons/year, an emission offset of 1:1 of the emission increase is required.

R307-421-4. General Requirements.

(1) All emission offsets shall meet the general requirements for calculating and banking emission offsets that are established in R307-403-4, R307-403-7 and R307-403-8.

(2) Emission offsets shall be used only in the county where the credits are generated. In the case of sources located outside of Salt Lake or Utah Counties, the offsets shall be generated in the county where the modeled impact in R307-421-2(2) occurs.

(3) Emission offsets shall not be traded between pollutants.

R307-421-5. Transition Provision.

This rule will become effective in each county on the day that the EPA redesignates the county to attainment for PM10. The PM10 nonattainment area offset provisions in R307-403 will continue to apply until the EPA redesignates each county to attainment for PM10.


air pollution, offset, PM10, PM2.5

Date of Enactment or Last Substantive Amendment

July 7, 2005

Notice of Continuation

May 15, 2017

Authorizing, Implemented, or Interpreted Law

19-2-101(1)(a); 19-2-104; 19-2-108

Additional Information


For questions regarding the content or application of rules under Title R307, please contact the promulgating agency (Environmental Quality, Air Quality). A list of agencies with links to their homepages is available at http://www.utah.gov/government/agencylist.html or from http://www.rules.utah.gov/contact/agencycontacts.htm.