From: Yanca, Catherine

To: "Susan Collet (TEMA TTC)"

Cc: "yukio kinugasa.tec.toyota.co.jp" ; "Hiroaki Minoura (TEMA TTC)" ; Sargeant, Kathryn

Subject: RE: Request: Clarifying Questions for Tier 3 Air Quality modeling

Date: Thursday, July 18, 2013 4:06:00 PM

Attachments: County site table 8hrO3.xlsx

Hi Susan,

Thanks again for your questions on the Tier 3 Air Quality Modeling Technical Support Document.

Our responses are below, along with an attached Excel spreadsheet in answer to question 1.

Best,

~Cay

1. What is the measurement location for each site in the “Appendix B, 8-Hour Ozone

Design Values for Air Quality Modeling Scenarios” ?

Specifically, we’d like to know the address, coordinates, altitude and population of

the locations:

LA, San Bernardino, Riverside, Phoenix, Denver, Detroit

, NY, Atlanta

An example excel sheet is attached.

The attached Excel spreadsheet includes the monitor site ID, latitude/longitude and

2020/2030 population for each site in Appendix B. As a routine measure, we don’t have

addresses or altitudes.

2. How and why was one representative AQS location selected in a county?

We calculated Relative Response Factors (RRFs) and Design Values (DVs) for all monitor

locations which had valid ambient data meeting EPA’s modeling guidance (p.23,

http://www.epa.gov/ttn/scram/guidance/guide/final-03-pm-rh-guidance.pdf ). However,

for purposes of the table providing 8-hour ozone DVs for the Tier 3 air quality modeling

scenarios (Appendix B), selection of a representative AQS (monitor) location for DV

calculation differences is based on the monitor with the highest DV concentration in a

county which is consistent with the projected change county maps in 8-hr ozone DVs

between the Tier 3 reference and control cases seen in Figures III-1 and III-2, p. 11

http://www.epa.gov/otaq/documents/tier3/454r13006.pdf )

.

3. With CMAQ simulation, 10 highest days in a year are selected and averaged to

determine the relative response factor (RRF).

What was the grid size (12 or 36 km) and how many grids were used (3*3, 5*5,

7*7)?

The grid size (domain) of the CMAQ simulation was 12km and the nearby grid cells used to

calculate the RRFs were based on 3x3 (see p. 26, Table 3.2 for default recommendations for

nearby grid cells used to calculate RRFs

http://www.epa.gov/ttn/scram/guidance/guide/final-03-pm-rh-guidance.pdf ).4. Did you simulate all days of the year for 2005, 2017, and 2030?

Yes, 2005, 2017, and 2030 are complete annual (all days) simulations (see section II. C., p. 4

from AQM TSD http://www.epa.gov/otaq/documents/tier3/454r13006.pdf ).

Catherine (Cay) A. Yanca

US EPA Office of Transportation and Air Quality

Assessment and Standards Division

2000 Traverwood Drive

Ann Arbor, MI 48105

Phone: 734.214.4769

From: Yanca, Catherine

Sent: Wednesday, July 03, 2013 1:21 PM

To: 'Susan Collet (TEMA TTC)'

Cc: yukio kinugasa.tec.toyota.co.jp; Hiroaki Minoura (TEMA TTC); Sargeant, Kathryn

Subject: RE: Request: Clarifying Questions for Tier 3 Air Quality modeling

Hi Susan,

Thanks for sending these questions. We’ve discussed them and think we can answer all via email.

We are currently working on responses and plan to have something to send back to you soon.

Regards,

~Cay

Catherine (Cay) A. Yanca

US EPA Office of Transportation and Air Quality

Assessment and Standards Division

2000 Traverwood Drive

Ann Arbor, MI 48105

Phone: 734.214.4769

From: Susan Collet (TEMA TTC) [ mailto:susan.collet@tema.toyota.com ]

Sent: Monday, June 24, 2013 11:39 AM

To: Yanca, Catherine

Cc: yukio kinugasa.tec.toyota.co.jp; Hiroaki Minoura (TEMA TTC)

Subject: Request: Clarifying Questions for Tier 3 Air Quality modeling

Hello Cay,

We have a few clarifying questions regarding “Air Quality Modeling Technical Support

Document:

Proposed Tier 3 Emission Standards.”We know Rohit Mathur from Coordinating Research Council (CRC) and he suggested we

contact you.

I’m ok with looking at a website for the complete reply, if you would provide the URL. But, I

can’t find these answers on the internet.

5. What is the measurement location for each site in the “Appendix B, 8-Hour Ozone

Design Values for Air Quality Modeling Scenarios” ?

Specifically, we’d like to know the address, coordinates, altitude and population of

the locations:

LA, San Bernardino, Riverside, Phoenix, Denver, Detroit

, NY, Atlanta

An example excel sheet is attached.

6. How and why was one representative AQS location selected in a county?

7. With CMAQ simulation, 10 highest days in a year are selected and averaged to

determine the relative response factor (RRF).

What was the grid size (12 or 36 km) and how many grids were used (3*3, 5*5,

7*7)?

8. Did you simulate all days of the year for 2005, 2017, and 2030?

Thank you in advance for your reply,

Susan

(734) 995-2086