### Attachment

Comments on the November 2008 draft of the

Oregon Regional Haze SIP

**The Forest Service recognizes the complexities in a ssessing visibility in Oregon’s Class I**  **areas, due in part to the State’s diverse topograph y and source emission categories. Overall,**  **ODEQ provided a comprehensive assessment of visibil ity impairment in Class I areas. This**  **was extremely helpful in assessing the adequacy of the Reasonable Progress Goals and Long**  **Term Strategy. We offer the following comments and /or request clarification of the following** 

**issues.**

Source Apportionment

**We suggest ODEQ to include a discussion of the cont ribution of secondary organic aerosols**  **from biogenic emissions as natural sources of haze. A review of the WRAP TSS organic**  **aerosol modeling results verifies that indeed secon dary emissions from biogenic sources**  **contribute a large fraction of the organic carbon o bserved during the summer months in the**  **Wilderness areas (e.g. Mt. Hood Wilderness area). This is consistent with the finding of the**  **Columbia River Gorge Visibility Study in which biog enic emissions were found to be a major**  **contributor to summer-time haze. Secondary biogenic emissions can contribute significantly to**  **the organic carbon portion of haze, especially duri ng the summer months. Given the high**  **impact of organic carbon to regional haze during th e summer months, the lack of including**  **this source category may artificially lead one to a ttribute the contribution to another source**  **category. Please evaluate and revise this section accordingly.** 

Best Available Retrofit Technology (BART) Evaluatio n

**The proposed Best Available Retrofit Technology (BA RT) limit for NOx is 0.23 lb/mmbtu**  **based upon a 12-month rolling average. As in the c ase with NAAQS and PSD increments, we**  **would like to see consistency in the averaging time of the permit limit and regional haze.**  **Although regional haze is an instantaneous phenomen on, it is treated as a 24-hour average**  **phenomenon throughout the BART process and New Sour ce Review (NSR). The BART**  **guidelines recommend a 30-day rolling average for u tility boilers subject to the presumptive**  **limits. As such, we would like to see at least an equivalent 30-day rolling average for NOx** 

**limits from this unit.**

Comments on Reasonable Further Progress Goals:

**As none of the Class I areas in Oregon are expected to meet the Uniform Rate of Progress**  **(URP) goals by 2018, Oregon is proposing to establi sh Reasonable Progress Goals (RPGs)**  **that provide for a slower rate of improvement in vi sibility, at least through 2018. While a state**  **may establish reasonable progress goals that provid e for a slower rate of improvement than the** 

**rate that would be needed to attain natural conditi ons by 2064, the State must, (1) demonstrate**  **that URP goals are not reasonable, and (2) provide an assessment of the number of years it** 

**would take to attain natural conditions at the rate of progress selected by the State as** 

**reasonable. While Oregon has provided a four-factor analysis fo**  **r non-BART source categories, and the**

**costs of implementing some of these controls appear to the Forest Service to be reasonable,**  **Oregon has concluded that it is not reasonable to r equire controls for these source categories at**  **this time. Please clarify that (1) several of thes e source categories have costs that are within**  **the range of what is considered reasonable under th e BART or BACT programs, and (2)**  **clarify why Oregon is not pursuing reducing emissio ns from these sources now.** 

**Additionally, please provide an assessment of the n umber of years it would take to attain**  **natural conditions at the rate of progress selected by the State as reasonable.** 

Comments on the Long Term Strategy:

Fire: **Given the potentially large impact of wildfire on h aze, such events have the potential to have a**  **significantly larger impact on the magnitude of the average of the 20% worst case days, more**  **so than any other emission source. The Forest Ser vice would like Oregon to recognize, in its**  **regional haze SIP, the potential benefits of an imp lementing fuels reduction programs,**  **including prescribed burning, as a strategy for red ucing haze from wildfires. Such language is**  **already contained in Section 629-048-0020 of the Or egon Smoke Management plan**  **(Necessity of Prescribed Burning), including a desc ription of the likely differences in air**  **pollution effects of wildfires as compared with pre scribed burning.** 

**The Forest Service agrees that prescribed burning m ay contribute to haze in federal Class I**  **areas and further evaluation is needed. However, t he methodology proposed to evaluate the**  **contribution of prescribed forestry burning to haze has some inherent biases and uncertainties**  **that may result in artificial attribution to this s ource. The Forest Service would like to work**  **with ODEQ in formulating an appropriate evaluation technique, interpreting the results, and**  **identifying of any potential additional control tec hniques to mitigate such effects.** 

Non-BART Source Evaluation: **The Forest Service would like to participate in the development of the guidance for the**  **evaluation of non-BART sources to reduce regional h aze. We are further concerned about**  **how sources which have demonstrated that impacts fr om their emission unit are less than the**  **0.5 dv threshold, based upon actual, not permitted emission levels. These sources may still**  **have the potential to contribute to regional haze ( above the 0.5 dv) threshold if their actual** 

**emissions increase above values used in the BART ex emption modeling.** 

**Furthermore, we would like to see the State evaluat e the cumulative source impacts from a**  **grouping of sources, such as those that occur in th e lower Columbia River in Northwest**  **Oregon and Southwest Washington that together may cause haze in Class I areas. Such an**  **approach is commonly used in the Eastern US and see ms logical to apply here as well.** 

Area Sources of Organic Carbon:

**Organic carbon is identified as the largest contrib uting aerosol species to the 20% worst-case**  **days in the Class I areas of the Oregon Cascades. In the Mt. Hood Wilderness, and to a lesser**  **extent in the Mt. Jefferson, Mt. Washington, and Th ree Sisters Wilderness areas, organic**  **carbon is identified as the largest contributing so urce to organic carbon. However, there is no** 

**mention of how the State intends to address this so urce category as part of its Long-Term** **Strategy. Please add a discussion of area sources of organic carbon to the Long-Term Strategy** 

**for these wilderness areas.**

Crustal Material (Coarse Particulate Matter and Fin e Soil)

**We would like Oregon to address crustal material as part of its Long-Term Strategy for Class I**  **areas in Eastern Oregon, as these are more affected by this pollutant than the Oregon’s other**  **Class I areas. Examination of alpine lake sediment cores from the western interior United** 

**States have revealed a five-fold increase in dust d eposition since the early twentieth century,**  **coinciding with expansion of livestock grazing 1**  **. Eastern Oregon has well known wind blown dust episodes which are at times implicated using t**  **he Wind Blown Dust Episode Analysis tool available through the WRAP TSS. We encourage ODEQ**  **to use this tool and consider windblown dust not only as a natural source but als**  **o an anthropogenic source which may increase with land use disturbance in considering o**  **ptions to reduce dust emissions in the future. Please discuss this pollutant and potentia**  **l control strategies as part of Oregon’s Long Term Strategy.** 

Sulfates:

**Sulfates from area source have been implicated as s ignificant sources of haze causing**  **pollutants in the Mt. Hood Wilderness, which are no t expected to meet the 2018 URP. While**  **ODEQ did addressed stationary SO 2**  **fuel combustion sources the analysis a more thorou gh**  **analysis is warranted considering the impact on thi s Class I wilderness area. In addition to**  **fuel switching and post-combustion controls, which ODEQ has somewhat addressed, other**  **options to reduce emissions from this source catego ry may include working with pollution**  **prevention and conservation experts to evaluate the full suite of options and make**  **recommendations for future sustainability. We enco urage Oregon to consider sustainability**  **and energy conservation as part of its Long-Term St rategy for all pollutants, including** 

**sulfates.**

• **The Forest Service routinely requests that SIPs inc lude language linking the Regional Haze**  **Program with the Prevention of Significant Deterior ation program. We note that the PSD**  **program can be an effective tool to prevent degrada tion of “Best Days”, and that new sources** 

**should be consistent with or accounted for in RH SI P revisions.** 

**1 Neff, J.C, et al. Increasing Eolian Dust Depositi**  **on in the Western United States Linked to Human Act ivity.**  **Nature Geoscience. Vol. 1, March 2008. www.nature .com/naturegeoscenice.**