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Department of Environmental Quality regon Headquarters 

811 SW Sixth Avenue 

Portland, OR 97204-1390 

John A. Kitzhaber, MD, Governor 

(503) 229-5696 

FAX (503) 229-6124 

TTY: 711 

May 7, 2012 

Debra Suzuki 

Manager, State & Tribal Air Programs Unit 

U.S. EPA Region 10 


1200 Sixth Avenue, Suite 900 


Seattle, W A 98101 


Dear Ms. Suzuki, 

In response to your request, Oregon DEQ is providing EPA with a recalculation ofthe time needed to 

attain natural conditions for Oregon Class I areas, in accordance with the Regional Haze rule under 

Section 308(d)(I)(ii). In providing this information, it should be noted that while our projections for 

visibility improvement in Oregon Class I areas did not meet the 2018 Milestone goal, we are not 

convinced attaining natural conditions by 2064 should be abandoned as a future goal. In our regional 

haze plan we projected significant reductions in man-made pollutants (S02 and N02) by 2018, and 

beyond (much ofthis due to the PGE Boardman plant closure in 2020), and that the primary reason for 

not meeting the 2018 Milestone was due to uncontrollable natural sources, such as wildfire and 

windblown dust. 

The alternative dates to 2064 for attaining natural conditions are provided below. Some Class I areas are 

grouped together, based on the IMPROVE monitoring site that represents the Class I area and the 20% 

worst day baseline visibility value. 

Year - Oregon Class I Area 

2087 - Mt. Hood Wilderness Area 

2095 - Mt. Jefferson, Mt. Washington, and Three Sisters Wilderness Areas 

2289 - Diamond Peak, Mountain Lakes, and Gearhart Mountain Wilderness Areas, and Crater Lake 

National Park 

2218 - Kalmiopsis Wilderness Area 

2127 - Strawberry Mountain and Eagle Cap Wilderness Areas 

2076 - Hells Canyon Wilderness Area 

The calculations for these dates were made as follows. 

1. 	 Using the 20 percent Worst Days for each Class I area, the original glideslope to 2064 was based 


on a regression line starting with baseline visibility (dv) in 2004, and going to out 2064. The point 


on the glides lope for 2018 represented the 2018 Milestone (also known as the uniform rate of 


progress goal). 

2. 	 DEQ's Reasonable Progress Goals (RPG) for 2018 were based on visibility projections for that 

year. 

3. 	 Calculating the alternative dates for attaining natural conditions requires using the 2004 baseline, 

the 2018 RPG, and then applying a regression equation (y - yl = m(x - xl) m = (y2-yl)/(x2-xl) to 

calculate the new year to attain natural conditions (identical to the 2064 visibility (dv) value). 

Oregon Class I Area 

20% Worst 

Day Baseline 

(dv) 2004 

2018 

Milestone 

(dv) 

Reasonable 

Progress Goal 

(dv) 2018 

Natural 

Conditions 

(dv) 

NewNC 

Year 

Mt. Hood Wilderness 14.9 13.4 13.8 8.4 2087 

Mt. Jefferson, Mt. Washington, 

and Three Sisters Wilderness 

Areas 15.3 13.8 14.3 8.8 2095 

Diamond Peak, Mountain 

Lakes, and Gearhart Mountain 

Wilderness Areas and Crater 

Lake National Park 13.7 12.3 13.4 7.6 2289 

Kalmiopsis Wilderness Area 15.5 14.1 15.1 9.4 2218 

Strawberry Mountain and Eagle 

Cap Wilderness Areas 18.6 16.3 17.5 8.9 2127 

Hells Canyon Wilderness Area 18.6 16.2 16.6 8.3 2076 

If you have further questions, please contact Brian Finneran of my staffat 503-229-6278. 

Sincerely, 

~-7 

Andrew Ginsburg 

DEQ Air Quality Administrator 

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