From: Kotchenruther, Robert

To: Chi, John

Subject: RE: Review Assistance

Date: Tuesday, May 24, 2016 1:17:10 PM

Hi John,

Sorry it took me a while, it was a while since I had looked at the Medford CO emissions inventory,

 and I didn’t remember seeing the final version, so wanted to quickly look through it and make sure

 everything looked okay. It does look okay, and I don’t see anything in what you wrote below that is

 any problem.

Cheers

Bob

========================================

Robert Kotchenruther, Ph.D.

Environmental Scientist

U.S. EPA Region-10

Office of Environmental Review and Assessment

1200 Sixth Avenue, Mailstop OERA-140

Seattle, WA 98101-3140

(206) 553-6218

Kotchenruther.Robert@epa.gov

========================================

From: Chi, John 

Sent: Thursday, May 19, 2016 10:26 AM

To: Kotchenruther, Robert <Kotchenruther.Robert@epa.gov>

Subject: Review Assistance

Hi Bob,

I’m working on the Medford CO Second 10-Year Maintenance Plan. Claudia reviewed my draft for

 me and recommended that I ask you to review the following section on the emissions inventory or

 potentially review the emissions inventory for the plan and write a memo to be used for this

 section. I think the first option would be more ideal, but if you see anything glaring please let me

 know. Thank you again for your help!

A. Base Year Emissions Inventory

 The LMP must contain an attainment year emissions inventory to identify a level of CO

 emissions in the area that is sufficient to attain the CO NAAQS. The submittal, contains a summary

 of the CO emissions inventory for the Medford area for the base year 2008. The emission inventory

 lists CO emissions by general source category – stationary point sources, stationary area sources,

 on-road mobile sources and non-road mobile sources. On-road mobile sources emissions for the
 2008 base year inventory were estimated with the EPA’s Motor Vehicle Emissions Simulator

 (MOVES) 2010b.[1] The methods used to determine the Medford area CO emission inventory are

 consistent with the EPA’s most recent guidance on developing emission inventories.

Historically, exceedances of the CO standard in the Medford area have occurred during the

 winter months, when cooler temperatures contribute to incomplete combustion, and when CO

 emissions are trapped near the ground by atmospheric inversions. Sources of carbon monoxide

 include industry, motor vehicles, non-road mobile sources, (e.g., construction equipment,

 recreational vehicles, lawn and garden equipment, and area sources (e.g., outdoor burning,

 woodstoves, fireplaces, and wildfires). The CO season is defined as three consecutive months -

 December 1 through the end of February. As such, season day emissions in addition to annual

 emissions are included in the inventory. The unit of measure for annual emissions is in tons per year

 (tpy), while the unit of measure for season day emissions is in pounds per day (lb/day). In addition,

 the county-wide emissions inventory data is spatially allocated to the Medford urban growth

 boundary (UGB), and to buffers around the UGB, depending on emissions category.

2008 Emissions Inventory, Main Source Category Subtotals

Main Source Category Annual Emissions

Tons per Year

CO Emissions

Pounds per Winter Day

Stationary Point Sources 2.367.1 13,159

On-road Mobile Sources 5,730.0 28,731

Non-road Mobile Sources 4,488.2 10,061

Stationary Area Sources 3,333.1 30,399

Total 15,927.4 82,350

John Chi

EPA Region 10

Office of Air and Waste

(206) 553-1185

[1] MOVES2010b was the most current model available at the time that the ODEQ was performing its analysis. The

EPA released MOVES2014 on October 7, 2014 (79 FR 60343).