UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION III

	1650 Arch Street

	Philadelphia, Pennsylvania  19103

DATE:	November 10, 2010

SUBJECT:	Technical Support Document for Virginia’s Adoption of the
8-hour Ozone Standard, Related Reference Conditions, and Update of
Appendices 

			/s/

FROM:	Irene Shandruk, Physical Scientist 

Office of Air Program Planning 

TO:		File

			/s/	

THRU: 	Brian Rehn, Acting Associate Director 

Office of Air Program Planning

A.  BACKGROUND  

This technical support document (TSD) evaluates the September 27, 2010
submittal of the Virginia State Implementation Plan (SIP) revision
pertaining to the ambient air quality standard for ozone and related
reference conditions.

The Clean Air Act (CAA) specifies that EPA must reevaluate the
appropriateness of its various air quality standards every five years. 
As part of the process, EPA reviewed the latest health-based research
and determined that a revised standard for ozone was necessary to
protect public health.  EPA revised the level of the 8-hour standard to
a level of 0.075 parts per million (ppm) to provide increased protection
for children and other ‘‘at risk’’ populations against an array
of ozone-related adverse health effects that range from decreased lung
function and increased respiratory symptoms to serious indicators of
respiratory morbidity including emergency department visits and hospital
admissions for respiratory causes, and possibly cardiovascular-related
morbidity as well as total non-accidental and cardiorespiratory
mortality.  Based on this information, EPA promulgated a more stringent
national ambient air quality standard (NAAQS) for ozone on March 27,
2008 (73 FR 16436).

B.  STATE SUBMITTAL

On September 27, 2010, the Commonwealth of Virginia submitted a formal
revision to its SIP.  The SIP revision consists of an amendment which
includes the revised ambient air quality standard for ozone, and related
reference conditions.  Virginia(s revision incorporates the Federal
8-hour ozone standard into the Code of Virginia (9VAC5 Chapter 30).  In
addition, the list of appendices to 40 CFR Part 51 was updated under
documents incorporated by reference (9VAC5-20-21).

The following are the specific provisions that are being modified or
added:

9VAC5-20-21:  Documents incorporated by reference (modified)

	The list of appendices were updated.

9VAC5-30-55:  Ozone (8-hour, 0.08 ppm) (modified)

	The level of 0.08 ppm was added to the regulation.

9VAC5-30-56:  Ozone (8-hour, 0.075 ppm) (added)

	A new section was added for the revised 8-hour ozone NAAQS of 0.075
ppm.

C.  EPA EVALUATION

Virginia’s SIP revisions for the ambient air quality standard for
ozone is consistent with the 8-hour Federal ozone standard.

D.  CONCLUSIONS AND RECOMMENDED AGENCY ACTION

EPA approval of the SIP revision is recommended.

