[DAR NOTE: this document contained special formatting that did not translate when the document was converted to HTML. For the correctly formatted document, please see PDF copy of the Bulletin at https://rules.utah.gov/publicat/bull-pdf/2012/b20120701.pdf. ]

(The Division of Air Quality (DAQ) is proposing the repeal and reenactment of Air Quality Rule R307-202, Emission Standards: Open Burning (DAR No. 35923, published in the 04/01/2012 Bulletin; and an additional CPR, DAR No. 35923 published in this issue, 07/01/2012, of the Bulletin), which is part of Utah's PM10 state implementation plan (SIP). Section 110(l) of the Clean Air Act (CAA) states that EPA cannot approve a SIP revision if the revision would interfere with any applicable requirement concerning attainment and reasonable further progress or any other applicable requirements of the CAA. Therefore, a state must make a demonstration that a revision to a SIP shall not cause adverse conditions. This document, which is available for public review until 07/31/2012 shows that the proposed repeal and reenactment of Rule R307-202 will not cause adverse conditions. It demonstrates that in southern Utah, PM 2.5 levels are extremely low, even though that portion of the state experiences frequent wildfires and prescribed burning and that modifying the burning season in southern Utah will not adversely impact air quality. It also shows that PM2.5 levels in northern counties are well below the ambient standard during the proposed burning season. Comparing PM2.5 data from areas where previous fall open burning windows were allowed and areas where they were not indicates that open burning under this rule does not have substantial impact on air quality, see the following .)

Memo to File: R307-202 Emissions Standards: General Burning Amendment

Re: Demonstration - Air Quality Impact of Proposed Burning Window Shifts Statewide

Date: May 2012

Prepared by: Joel Karmazyn

The Air Quality Board amended the rule in 2004 to adjust the 30-day burning window between March 1- May 30, statewide. Local county fire marshals establish the 30-day window during this period. The Air Quality Board is now proposing rule amendments to establish separate burn windows for southern and northern counties and to permit burning during the entire period (eliminate the 30-day window), so long as the clearing index is 500 or greater.

  Current Burning Windows           Changed Burning Windows



  March 1 - May 30 statewide        Southern counties March 1 - May 30



  Sept. 15 - Oct. 30 attainment     Southern counties Sept 15 - Nov. 30

  counties

Item 1 Demonstration – Southern Counties Window Shift

Data from the IMPROVE monitoring at Bryce, Canyonlands and Zion National Parks represents southern Utah regional air quality. IMPROVE data do not include flags to exclude exceptional events, such as high winds and natural fires, thus this data represents worst case air quality. The following table presents the arithmetic mean of PM2.5 values from 2004-2010, which are extremely low and include emissions from past years of open burning starting on March1. The maximum values are likely indicators of wildfire and prescribed burning.

2007 values were influenced by one of the worst southern California wildfire years.

                    Mean     Mean     Mean     Mean     Mean     Mean     Mean    Maximum   
                    PM2.5    PM2.5    PM2.5    PM2.5    PM2.5    PM2.5    PM2.5   Value from
                    2004     2005     2006     2007     2008     2009     2010    2004-2010
                    Ug/m3    Ug/m3     Ug/m3    Ug/m3    Ug/m3    Ug/m3    Ug/m3    Ug/m3


Bryce Canyon
National Park,      2.34     2.38     2.47     3.02     2.83     2.89     2.04    18.3
Garfield County


Canyonlands
National Park       2.47     2.48     2.62     3.08     2.97     2.94     2.52    22.8
San Juan County


Zion National
Park,               2.71     2.89     3.29     3.90     3.54     3.02     2.52    18.6
Washington
County

The following table presents the acreage burned by large wildfires from 2004-2010. Large fires are defined as fires of 100+ acres of forest or 300+ acres of grassland (smaller fires also existed). This data does not include prescribed fires conducted by the Forest Service. A very large wildfire occurred near the Zion National Park monitoring station in 2006 that explains the increase in PM2.5 that year.

                                 Large Fires in Acres


 County            2004     2005     2006     2007     2008     2009     2010


 Garfield             0      435        0    2,392    3,733    6,067      966
 San Juan             0      973        0        0        0    2,631        0
 Washington      65,818  149,780  132,628   10,633        0   15,699      966

Emissions allowed under R307-202 are minimal in comparison to wildfires and prescribed burns and because current conditions do not threaten nonattainment areas that are separated by many miles and mountain ranges, it is concluded that shifting the open burning windows for southern counties and allowing burning throughout the burn season will not cause adverse conditions.

Item 2 Demonstration - Northern Counties Window Shift

The following table provides maximum PM2.5 values from monitoring data from September 15 to October 30. The monitoring stations represent southern, mid and northern stations within this portion of the state.

                            Maximum PM2.5 Values in Ug/m3


                  2004     2005     2006     2007     2008     2009     2010
     
    Hawthorne     15.4     14.4     13.2     19.3     16.6     14       10.7  
    
    Ogden         26       11       11       16.7     11.9     17.2     11.2
    
    Logan         18.8     12       12.1     16.6     11.2     14.4     15.8

The Hawthorne and Ogden locations did not have past fall burn windows, the Logan location has. Comparison between the Ogden station where burning did not occur and the Logan station where it has in the past, indicates that the newly proposed burning window should not result in adverse air quality conditions.

The following table presents the number of acres burned from large wildfires and prescribed fires during the proposed fall burn window.

 Large Wildfires and Prescribed Fires in Acres from September 15 to October 30


    County         2004    2005    2006    2007    2008    2009    2010


    Salt Lake                      860                             4,326


    Weber           45    900/640         300      300


    Cache                                 100                      1,520
		Large wildfires in bold, prescribed fires in black

The fire data indicates that there was minimal, if any, substantial air quality impact between when fires occurred and no fires. Therefore, it is concluded that the proposed fall open burning season will not cause adverse conditions.

[DAR NOTE: this document contained special formatting that did not translate when the document was converted to HTML. For the correctly formatted document, please see PDF copy of the Bulletin at https://rules.utah.gov/publicat/bull-pdf/2012/b20120701.pdf. ]