### Summary	of	Interagency	Working	Comments	on	Draft	Language	under

EO12866/13563	Interagency	Review.		Subject	to	Furthe r	Policy	Review.

1 **Environmental Protection Agency (EPA) :**  **Proposed Rule**  **Cross**

**- State Air Pollution Rule for the 2008 Ozone**  **National Ambient Air Quality Standards**

**RIN 2060**

**- A**  **S05**
**General Comments**

1. The proposed rule clearly intends to manage ozone transport through CSAPR, focusing on EGUs. However, anthropogenic emissions from Canada and Mexico and Fires are specificall y identified as contribution categories in the “source apportionment run” (page 1 03 of the preamble). The reviewer believes that states could propose controls on wildland fire emissions, since these emissions are specifically included as a contribution category , even if the primary

control mechanism focuses on EGUs. The reviewer also believes that wildland fire emissions may

contribute to ozone NAAQS exceedances in nonattainment and maintenance areas in a number of the 23 states. EPA Response : While wildfires do contribute to ozone formation, the EPA did not consider fires to be part of the anthropogenic emissions that were tracked in the source apportionment modeling for each state. The fire emissions were “tagged” as a separate source category (for the entire domain, not for each individual state), and therefore the interstate ozon e contributions did not include contributions from either wildfires or prescribed fires. The domain wide wildfire and prescribed fire ozone contributions to each downwind ozone receptor are quantified in the summary model contributions.

2. Wildland fire emi ssions are highl y variable annually in source, impact, geographic area, and extent. In 2015, emissions impacts the CSAPR area from Alaska, California, the Pacific Northwest, and especially , from Canada. In other y ears, wildland fire emissions from Mexico , Texas or the Southeastern states have impacted the CSAPR. Therefore, the reviewer recommends clarifying that the modeled baseline y ear of 2017 in the RIA includes the range of possible wildland fire emissions. EPA Response : The modeling emissions and meteorological base ye ar is 2011. Therefore, “actual” wildfire and prescribed fire emissions for 2011 were used in the modeling. These are based on emissions modeling techniques which estimate the emissions that occurred in 2011 from fires and place those emissions in the location that they occurred (the grid cell) at the time that they

occurred. For the future y ear 2017 modeling, the anthropogenic emissions are projected to 2017 based on our best estimate of growth and controls b etween 2011 and 2017. However the fire emissions are held constant between the base and future years (2011 and 2017) due to the fact that we are most interested in the impact of expected anthropogenic emissions changes and we don’t know how or where fires would occur in the future compared to what occurred in 2011.
3. Despite the impacts of wildland fire emissions, there are very positive effects from prescribed fire and other wildland fire management actions that reduce wildfire risks. Therefore, the

### Summary	of	Interagency	Working	Comments	on	Draft	Language	under

EO12866/13563	Interagency	Review.		Subject	to	Furthe r	Policy	Review.

2 reviewe r recommends that language included in the attachment to the EPA October 1, 2015 Memorandum on Implementing the 2015 Ozone National Ambient Air Quality Standards to Regional Administrators be incorporated within the preamble of this proposed rule. This language provides a succinct summary of many concepts regarding the ecological role of fire, and the relationship between wildland fire (wildfire and prescribed fire) and the management of ozone and ozone precursor emissions, that have been published over th e past y ear and have been included in other air quality rulemaking packages.
a. “Emissions from W

ildland Fires. We understand that fire is an unavoidable
occurrence on man y ty

pes of wildland, and that changing climate conditions will increase the occurrence o f damaging wildfires unless fuel loads are managed by other means including science

- based use of prescribed fire. 12,13,14 Emissions from fires on wildland, particularl y large wildfires, can impact concentrations of ozone and other harmful pollutants, such as PM2.5
, both in the locations with fire and down wind. In areas where wildfire have been prevalent or are likely we encourage air agencies to work with state, federal and private land managers on promoting prescribed fire and other strategies that may

re duce wildfire emissions and their effects on ozone exceedances; we appreciate that such strategies may have other public safety , ecological, and propert y protection benefits as well. Recognizing the importance of various fire management strategies, in the proposed revisions to the Exceptional Events Rule we intend to encourage air agencies to rely on burn managers’ use of basic smoke management practices15 b y identifying a set of generall y applicable practices that would be employ ed during prescribed fires. The EPA and the federal land management agencies will support state efforts to educate the public on the ecological role of fire, and wildfire and prescribed fire concepts. Where a prescribed fire program has been developed and is being implemented in and /or upwind of a nonattainment area, the EPA recommends that air agencies account for the expected prescribed fire emissions in the attainment and maintenance planning process. In those areas where prescribed fires are known to be capable of causing occasio nal ozone exceedances, the EPA will continue to work with air agencies and stakeholders to improve the long

- term effectiveness of the existing basic smoke management practices and smoke management programs.” EPA Response: Fires were specifically

excluded f

rom the upwind state to downwind receptor ozone contributions. So the upwind emissions that are available to be reduced to eliminate significant contribution do not include fire emissions. This rule specifically addresses interstate transport of anthropo genic ozone and ozone precursors . EPA will add language noting that EPA recognizes that both in

- state and upwind wildfires may contribute to ozone and EPA encourages all states to consider how appropriate use of prescribed fire may result in fewer ozone e xceedances for both them and their neighbors, to the benefit of public health.

4. Reviewer recommends referencing the pending Exceptional Events Rule proposal that was referred to in the 2015 Ozone NAAQS.

### Summary	of	Interagency	Working	Comments	on	Draft	Language	under

EO12866/13563	Interagency	Review.		Subject	to	Furthe r	Policy	Review.

3 EPA Response: EPA will add the following language: “ Wildland fire emissions may contribute to ozone exceedances, under the exceptional events rules in 40 CFR 50.14, certain emissions from wildland fires can be excluded from an y determination of a NAAQS exceedance if they meet certain requirements. Among those exceptional event requirements for wildland fires is the requirement to implement a certified Smoke Management Program or employee basic smoke management practices, both of which are used to control wildland fire emissions. EPA is in the process of undertaking a revision of the exceptional events rules to further define and clarify the treatment of wildland fires, but there is and will continue to be a regulatory mechanism for excluding such emissions from an y ozone exceedance determinations, so long as those emissions meet the relevant criteria. ” **Regulatory Impact Analysis**

1. Page 3

- 8, Table 3

- 1. Reviewer recommends using standard language for wildland fires and therefore changing “Wild and Prescribed Fires” to “Wildfires and Prescribed Fires.
EPA Res ponse: EPA will update the table header consistent with the comment.