UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 10 1200 Sixth Avenue, Suite 900 Seattle, WA 98101-3140
OFFICE OF

AUG 232013 AIR, WASTE AND TOXICS 

### Stu Clark, Air Quality Program Manager Washington. State Department of Ecology PO Box 47600 Olympia, WA 98504-7600 Re: Review of Draft Chapter 173-476 Washington Administrative Code (WAC) Ambient Air Quality Standards Dear Mr. Clark: We have reviewed the draft version of "Chapter 173-476 WAC Ambient Air Quality Standards" to identify potential deficiencies prior to final submission of the regulation for EPA approval. When compared to the current Environmental Protection Agency (EPA) National Ambient Air Quality Standards, we have concluded that the draft version sent to the EPA on July 3, 2013, would likely be approvable into the Washington State Implementation Plan pending one minor change discussed on page 10 of the attached supporting memorandum. As discussed with your staff, the EPA intends to formally comment on this issue during the state public comment period. The EPA will make a final decision based on our review of the complete State Implementation Plan revision submitted following your public process and after consideration of any comments received by you. If you have any questions please feel free to contact me at 206-553-1271 or have your staff contact either Debra Suzuki, Air Programs Unit Manager, at 206-553-0985 or Jeff Hunt, staff lead, at 206-553-0256.

Ka e I lly, ► tor Office of aste, and ToxicsJ^^^asrgr UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Fs-r REGION 10 1200 Sixth Avenue, Suite 900 .D3 

## tt o Seattle, WA 98101-3140 PRo 

### - O 

### August 16, 2013 MEMORANDUM SUBJECT: Review of Draft Chapter 173-476 WAC Ambient Air Quality Standards FROM: Jeff Hunt, Air Quality Planner
TO: Debra Suzuki, Air Programs Unit Manager The Washington Department of Ecology (Ecology) asked the EPA to review a draft version of Chapter 173-476 Washington Administrative Code (WAC) Ambient Air Quality Standards, so that any errors or EPA concerns can be addressed prior to final submission for approval into the State Implementation Plan (SIP). Attachment A is a copy of the draft rule language annotated with my analysis of the provisions. Attachment B is my analysis of the supporting SIP revision documentation. Once Ecology makes the minor correction identified on page 10 of Attachment A, I believe this draft version of Chapter 173-476 WAC meets the Clean Air Act requirements for incorporation into the SIP barring any significant public comments or changes in EPA policy. Creation of a sample proposed Federal Register notice In order to identify all relevant issues to the best of my ability, I drafted a sample Federal Register notice based on the Approval and Promulgation of Implementation Plans; Georgia; State Implementation Plan Miscellaneous Revisions recently published by the EPA on May 16, 2013. This Federal Register updates the Georgia SIP to reflect the EPA's current National Ambient Air Quality Standards (NAAQS) for sulfur dioxide, nitrogen dioxide, ozone, lead, and particulate matter similar to Ecology's draft rule language. This sample Federal Register notice is included as Attachment C. Upon submission of a final SIP revision, I will review any changes to Ecology's final rule language along with any comments received during the state public comment period and revise this draft as appropriate. OFFICE Or AIR, WASTE AND'1 

### ° OXIC:S

### Attachment A - the EPA's Analysis of Draft Chapter 173-476 Washington Administrative Code (WAC) Ambient Air Quality Standards 

### Chapter . 173-476 WAC AMBIENT AIR QUALITY STANDARDS NEW SECTION WAC 173-476-010 Purpose. This chapter establishes maximum acceptable levels in the ambient air for particulate matter, lead, sulfur dioxide, nitrogen oxides, ozone, 

## and carbon monoxide.. EPA analysis - this introductory text is worded differently than 40 CFR 50.2, but the general framework is consistent with the EPA text.

NEW SECTION

WAC 

### 173-476-020 Applicability. (1) The provisions of this chapter apply to all areas of the state of Washington. (2) All federal,regulations referenced in this regulation are adopted as they exist on August 3, 2013. EPA analysis - the EPA supports statewide applicability of the NAAQS. This should lessen the burden on local agencies when future EPA NAAQS are updated. 2

### NEW SECTION

WAC 173-476-030 Definitions. (1) Unless a different meaning is clearly required by context, words and phrases in this chapter have meanings consistent with general terms defined in chapter 173-400 WAC. (2) Definitions specific to this chapter: (a) "Period" means any interval of the specified time. (b) "ppmv" means parts per million by volume. EPA analysis - EPA typically uses the term "ppm" in our NAAQS, however Ecology's additional clarification of "ppmv" is consistent with our methodology. (c) "ppb" means parts per billion by volume, which is 1 part in 1,000,000,000 parts by volume. (d) "Federal Reference Method" or "FRM" means an EPA designated ambient air quality sampling and analysis method specified in an appendix to 40 C.F.R. Part 50, or a method that has been designated as a reference method according to 40 G.F.R. Part 53. It does not include a method for which a reference

3method designation has been canceled according to 40 C.F.R.

53.11 or 53.16. (e) "Federal Equivalent Method" or "FEN" means an EPA designated ambient air quality sampling and analysis method that has been designated as an equivalent method according 

### to 40 C.F.R. Part 53. It does not include a method for which an equivalent method designation has been canceled according to 40 C.F.R. 53.11 or 53.16. 

### EPA analysis - These definitions are consistent with the EPA definitions located iii 40 CFR 50.1

NEW SECTION WAC 173-476-100 Ambient air quality standard for particulate matter, PM-10. (1) Standard for PM-10. The twentyfour-hour average concentration of PM-.10 in the ambient air must not exceed 150 micrograms per cubic meter (pg/m 3 ) more than one time per year, on a three-year average. (2) Measurement method. The levels of PM-10 in the ambient air must be measured by:(a) A FRM based on 40 C.F.R. Part 50, Appendix J and

designated according to 40 C.F.R. Part 53; or (b) A FEM designated according to 40 C.F.R. Part 53. (3) Interpretation method. The interpretation method found in 40 C.F.R. Part 50, Appendix K must be used. 

### EPA analysis - this section is consistent with the EPA PM 10 NAAQS provisions 

### contained in 40 CPR 50.6 and Appendix K. Note that the EPA primary standard and the secondary standard for PM 1D are both 150 μg/m 3 

### . Throughout this draft rulemaking Ecology does not differentiate between primary and secondary standards, but instead incorporates all of them. This Ecology approach seems to be more straightforward and understandable compared to the EPA regulations,

NEW SECTION WAC 173-476-110 Ambient air quality standards for particulate matter, PM-2.5. (1) Standards for PM-2.5. (a) The three-year average of the annual arithmetic mean concentration of PM-2.5 must not exceed 12.0 micrograms per cubic meter (pg/m 3 ). (b) The three-year average of the ninety-eighth percentile twenty-four-hour average concentration of PM-2.5 must not exceed 35 pg/m 3 .

### (2) Measurement method. The levels of PM-2.5 in the ambient

air must be measured by: (a) A FRM based on 40 C.F.R. Part 50, Appendix L and designated according to 40 C.F.R.. Part 53; or (b) A FEM designated according to 40. C.F.R. Part 53. (3) Interpretation method. The interpretation method found in 40 C.F.R. Part 50, Appendix N must be used. EPA analysis - this section is consistent with the EPA PM2 . 5 

### NAAQS provisions contained in 40 CFR 50.18 and Appendix N.

NEW SECTION 

### WAC 173-476-120 Ambient. air quality standard for lead (Pb). (1) Standard for lead. The three-month rolling average concentration of lead (Pb) and its compounds in the ambient air must not exceed 0.15 micrograms per cubic meter (pg/m 3 ). (2) Measurement method. The levels of Pb in the ambient air must be measured by: (a) A FRM based on 40 C.F.R. Part 50, Appendix G and designated according to 40 C.F.R. Part 53; or
6(b) A FEM designated according to 40 C.F.R. Part 53. (3) Interpretation method. The interpretation method found in 40 C.F.R. Part 50, Appendix R must be used. 

### EPA analysis - this section is consistent with the EPA lead (Pb) NAAQS provisions contained in 40 CFR 50.16 and Appendix R.

NEW SECTION WAC 173-476-130 Ambient air quality standards for sulfur oxides (sulfur dioxide). (1) Standard for sulfur oxides (measured as sulfur dioxide). (a) Annual. The annual average concentration for sulfur oxides in the ambient air must not exceed 0.02 ppmv in a calendar year. 

### EPA analysis - this state standard of 0.02 ppm is more stringent than the federal annual standard of 0.030 ppm contained in 40 CFR 50.4. Under the provisions of 40 CFR 50.2(d) states may establish more stringent NAAQS.
(b) Twenty-four-hour. The twenty-four-hour average concentration for sulfur oxides in the ambient air must notexceed 0.1 ppmv more than once per calendar year. The twentyfour-hour averages must be determined from successive
7

### nonoverlapping twenty-four-hour blocks starting at midnight each

calendar day. EPA analysis - this state standard of 0.1 ppm is lower than the federal 24-hour standard of 0,14 ppm contained in 40 CFR 50.4. However, under certain rounding situations, discussed below, the state standard can be less stringent than the federal standard. Ecology has agreed to revise their rounding convention for the 24-hour standard, so this standard will likely be changed to 0.10 ppm. Alternatively, the state could adopt the federal standard of 0.14 ppm if desired. (c) Three-hour. The three-hour average concentration for sulfur oxides in the ambient air must not exceed 0.5 ppmv more than once per calendar year. The three-hour averages must be determined from successive nonoverlapping three-hour blocks starting at midnight each calendar day. EPA analysis - this section is consistent with the EPA's 3-hour sulfur oxides NAAQS provisions contained in 40 CFR 50.5.
(d) One-hour. The three-year average of the annual ninetyninth percentile of the daily maximum one-hour average concentrations for sulfur oxides in the ambient air must not exceed 75 ppb. EPA analysis - this section is consistent with the EPA's 1-hour sulfur oxides NAAQS provisions contained in 40 CFR 50.17 and Appendix T,

8(2) Measurement method. The levels of sulfur oxides must be

measured as sulfur dioxide by: (a) A FRM based on 40 C.F.R. Part 50, Appendix A or A-I; or (b) A FEM designated according to 40 C.F.R. Part 53. (3) Interpretation methods. (a) The annual arithmetic mean is based on the average of hourly data. To be used in calculating the annual average, the hourly data must be at least seventy-five percent complete in each calendar quarter of the year. (b) The interpretation method for the twenty-four-hour average found in 40 C.F.R. Part 50.4(d) must be followed. (c) The interpretation method for the three-hour average found in 40 C.F.R. Part 50.5(c) must be followed. (d) The interpretation method for the one-hour average found in 40 C.F.R. Part 50, Appendix T must be followed. (4) Rounding of values.

9

### (a) The annual arithmetic mean must be rounded to three

decimal places (fractional parts equal to or greater than 0.005 ppmv must be rounded up). EPA analysis - this state draft rule language uses one less significant digit in their rounding convention for the annual standard.than the EPA rounding convention found in 40 CFR 50.4(a). However, the state standard of 0.02 ppm is more stringent than the federal standard of 0.030 in all situations, so the difference in rounding conventions is fine from an EPA SIP approval standpoint. (b) The twenty-four-hour averages must be rounded to two decimal places (fractional parts equal to or greater than 0.05 ppmv must be rounded up). EPA analysis - with respect to the 24-hour standard, the difference in state and EPA rounding conventions would cause a problem from an EPA SIP approval standpoint. Because the state standard has one less significant digit, measured values in the 0.145 to 0.149 ppm range would be considered a violation of the federal standard but not the state standard; making the state standard less stringent in some situations. [See 40 CFR 50.2(d) for the EPA rounding convention]. As discussed with Ecology staff, the EPA intends to make this comment during the state public comment period. (c) The three-hour standard averages must be rounded to one decimal place (fractional parts equal to or greater than 0.05 ppmv must be rounded up).

EPA analysis -- this text matches the text of of 40 CFR 50,5(a) which states, "[the level of the 3-hour standard] shall be rounded to 1 decimal place (fractional parts equal to or greater than 0.05 ppm shall be rounded up)." 10(5) Sunset provision. The ambient standards in WAC 173-476-

130 (1) (a) and (b) are no longer applicable in a specific area one year after the effective date of the EPA's designation of. attainment status of that area for the standard in WAC 173-476- 130 (1)(d) and 40 C.F.R. 50.17. 

### EPA analysis - these sunset provisions are consistent with the sunset provisions contained 40 CFR 50.4(e).

NEW SECTION WAC 173-476-140 Ambient air quality standards for nitrogen oxides (nitrogen dioxide). (1) Standards for nitrogen oxides (measured as nitrogen dioxide). (a) The annual average concentration for nitrogen oxides in ambient air must not exceed 53 ppb (100 pg/m3) measured in the ambient air as nitrogen dioxide. (b) The three-year average of the ninety-eighth percentile of the daily maximum one-hour average concentration of nitrogen oxides must not exceed 100 ppb, as measured in the ambient air as nitrogen dioxide.

11(2) Measurement method. The levels of nitrogen oxides must

be measured as nitrogen dioxide by: (a) A FRM based on 40 C.F.R. Part 50, Appendix F; or (b) A FEM designated according to 40 C.F.R. Part 53. (3) Interpretation method. The interpretation method found in 40 C.F.R. Part 50, Appendix S must be followed. 

### EPA analysis - these provisions are consistent with the EPA's nitrogen oxides standard contained in 40 CFR 50.11
NEW SECTION WAC 173-476-150 Ambient air quality standard for ozone. (1) Standard for ozone. The three-year average o-f the annual fourth highest daily maximum eight-hour average concentration of ozone in the ambient air must not exceed 0.075 ppmv. (2) Measurement method. The levels of ozone in the ambient air must be measured by: (a) A FRM based on 40 C.F.R. Part 50, Appendix D and designated according to 40 C.F.R. Part 53; or (b) A FEM designated according to 40 C.F.R. Part 53.
123) Interpretation method. The interpretation method found

in 40 C.F.R. Part 50, Appendix P must be followed. 

### EPA analysis -- these provisions are consistent with the EPA's ozone standard contained in 40 CFR 50.15
NEW SECTION WAC 173-476-160 Ambient air quality standards for carbon monoxide. (1) Standards for carbon monoxide. (a) The eight-hour average concentration of carbon monoxide in the ambient air must not exceed 9 ppmv (10 milligrams per cubic meter) more than once per year. (b) The one-hour average concentration of carbon monoxide in the ambient air must
- not exceed 35 ppmv (40 milligrams per cubic meter) more than once per year. (2) Measurement method. The levels of carbon monoxide in the ambient air must be measured by: (a) A FRM based on 40 C.F.R. Part 50, Appendix C and designated according to 40 C.F.R. Part 53; or (b) A FEM designated according to 40 C.F.R. Part 53.
13(3) Interpretation method. An eight-hour average must be

considered valid if at least seventy-five percent of the hourly averages for the eight-hour period are available. In the event that only six (or seven) hourly averages are available, the eight-hour average must be computed on the basis of the hours available using six (or seven) as the divisor. (4) Rounding of values. When summarizing data for comparison with the standards, averages must be stated to one decimal place. Comparison of the data with the levels of the standards in ppmv must be made in terms of integers with fractional parts of 0.5 or greater rounding up. 

### EPA analysis - these provisions are consistent with the EPA's carbon monoxide standard contained in 40 CFR 50.8
NEW SECTION WAC 173-476-170 Monitor siting criteria. Ambient monitors must be sited as required in 40 C.F.R. Part 58. 

### EPA analysis -- the EPA encourages direct incorporation by reference of the monitor siting criteria, as Ecology did above.

14

### NEW SECTION

WAC 173-476-180 Reference conditions. (1) All measurements of air quality that are expressed as mass per unit volume (e. micrograms per cubic meter) must be corrected to: (a) A reference temperature of 25°C; and (b) A reference pressure of 760 millimeters of mercury (1,013.2 millibars (hectopascals)). (2) Exception for measurements of particulate matter (PM2.5) and Pb. Measurements of PM-2.5 and Pb must be reported based on the actual ambient air volume measured at the actual ambient temperature and pressure at the monitoring site during the measurement period. EPA analysis --- this provision is consistent with the EPA's reference conditions contained in 40 CFR 50.3

NEW SECTION WAC 173-476-900 Appendix A-Table of standards. 

## Disclaimer: This table is provided as an overview. See complete rule for more detail. 15Pollutant Averaging Time Level Remarks Measurement Method' Interpretation

Method Particle Pollution PM-10 24-hour 150 mg/m' Not to be exceeded more than once per year averaged over 3 years 40 C.F.R. Part 50,

Appendix J 40 C.F.R. Part 50,

Appendix K

_ PM-2.5 Annual 12.0 kglm' Annual mean, averaged over 3 years 40 C.F.R. Part 50;

Appendix L 40 C.F.R. Part 50,

Appendix N 24-hour 35 ,rglm' 98th percentile, averaged over 3 years Lead Rolling 3-month average 0,15 lrg/m' Not to be exceeded 40 C.F.R. Part 50, Appendix G 40 C.F.R. Part 50,

Appendix R Sulfur Dioxide Annual 0.02 ppmv Not to be exceeded in a calendar year 40 C.F,R, Part 50,

Appendix A or A-1 WAC 173-476-

130(3) 24-hour 0.1 ppm Not to be exceeded more than once per year 3-hour 0.5 ppm Not to be exceeded more than once per year 1-hour 75 ppb 99th percentile of 1-hour daily maximum concentrations, averaged over 3 years Nitrogen Dioxide Annual 53 ppb

_ Annual Mean 40 C,F,R. Part 50, Appendix F 40 C,F.R. Part 50,

Appendix S 1-how' 100 ppb 98th percentile of 1-hour daily maximum concentrations, averaged over 3 years Ozone 8-hour 0.075 ppm Annual fourthhighest daily maximum 8-hr concentration, averaged over 3 years 40 C.F,R, Part 50,

Appendix D 40 C.F.R. Part 50,

Appendix P
Carbon Monoxide 8-how' 9 ppm Not to be exceeded more than once per year 40 C.F,R, Part 50,

Appendix C WAC 173-476-

160(3) 1-hour 35 ppm 

### EPA analysis -- the summary information contained in this chart is consistent with the Ecology rule language for each of the NAAQS.

16

### Attachment B - the EPA's Review of Ecology's Draft SIP Revision

WASHINGTON STATE DEPARTMENT OF ECOLOGY 

# Including New 

# Chapter 173-476 WAC into the Washington State Implementation Plan

Rule SIP Revision

Air Quality Program 8/9/2013

17

## What is submitted?

Ecology submits to the Environmental Protection Agency (EPA) a new rule, Ambient Air Quality Standards, Chapter 173-476 WAC for inclusion into the Washington State Implementation Plan (SIP). The new rule incorporates the current National Ambient Air Quality Standards (NAAQS) for criteria pollutants. These standards are federally required and applicable statewide. The new chapter replaces the following chapters of the Washington Administrative Code: • Ch. 173-470 WAC Ambient Air Quality Standards for Particulate Matter (formerly Ch. 18-40 WAC) • Ch. 173-474 WAC Ambient Air Quality Standards for Sulfur Oxides (formerly Ch. 18-56 WAC) • Ch. 173-475 WAC Ambient Air Quality Standards for Carbon Monoxide, Ozone, and Nitrogen Dioxide These chapters are repealed. Of those chapters, WAC 173-470 1 was approved into the SIP on January 15, 1993 2 . - 

## What Ecology would like EPA to do with the submittal? Ecology proposes for EPA to take two actions: Approve the new rule, Ambient Air Quality Standards, Ch. 173-476 WAC, into the SIP. • Remove the repealed rule, National Ambient Air Quality Standards for Particulate Matter, Ch. 173-470 WAC, from the SIP. 

## Analysis of Submittal The new rule incorporates the NAAQS, current as of August 2013, for the following air pollutants: • Particulate matter (PM 10 ) • . Particulate matter (PM2.5) • Lead (Ph) • Sulfur oxides (SOx) (except for the annual and 24 hour standards) • Nitrogen oxides (NOx) • Ozone (0 3 ) • Carbon monoxide (CO) The rule retains Washington's current annual and 24-hour state standards for sulfur oxides. They are more stringent than the respective NAAQS.

1 Sections WAC 173-470-010, 020, and 160 were state adopted in 1987 and sections WAC 173-470-030 and 100 were state adopted in 1989. 2 58 FR 4578 

## 18The new rule does not include references to Total Suspended Particulate (TSP) found in SIP-approved

WAC 173-470(100)(1) and (2), EPA promulgated NAAQS for TSP in 1971. In 1987, EPA revised its particulate matter standards changing the indicator from TSP to PM-10 to focus on "inhalable" particles (<10 p.m), subsequently separating NAAQS for the "fine", PM 25i and "coarse", PM 10 , fractions of PM 10 in 1997. Ecology adopted these newer, and more protective, NAAQS and repealed the outdated standards for TSP. 

### EPA analysis -- the EPA agrees that it is appropriate for Ecology to remove the revoked 1971 TSP standard.The new rule also does not contain obsolete reporting requirement for local agencies found in SIPapproved WAC 173-470-160. Ecology and local clean air agencies have an elaborate monitoring network in place that collects monitoring data. Ecology's staff has access to the data collected. The data are also reported in real time on the agency's web site 3 . These data are being submitted regularly to EPA. 

### EPA analysis - the EPA agrees that the 1987 particulate matter reporting requirements found in the SIP-approved version of Chapter WAC 173-470-160 are obsolete and it is appropriate for Ecology to rely on the current monitoring network requirements contained in 40 CFR 58. In a letter dated October 25, 2012, the EPA approved the Washington Ambient Air Monitoring Network Plan which describes the Washington monitoring network for 2012-2013.. This annual review satisfies the state obligations under 40 CFR 58. By consolidating existing criteria pollutant rules into one rule, adding a Lead (Pb) standard, incorporating current federal NAAQS, and retaining existing, more stringent state SO2 standards, Ecology ensures it can implement and maintain the NAAQS as required by the federal Clean Air Act. Appendices below include: • Appendix A: New Chapter 173-476 WAC, adopted on [insert adoption date], proposed to be included into the SIP. • Appendix B: Current SIP-approved Chapter 173-470 WAC in red strike out indicating proposed removal from the SIP.

3 htt , : . j^www,ec^,l+va g^v(1rcJrarr s/^irf^%r monitori , ng^da , ta , ^ WAOA Intro Page ht3 i 19

## Appendix A

insert new rule language 

## Appendix , B

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473-4-7-Q-430 DEFINITIONS,
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### EPA analysis - removal of the 1993 SIP-approved version of Chapter WAC 173-470 Ambient Air Quality Standards for Particulate Matter is appropriate since all relevant provisions are contained in the new rule, Chapter 173-476 WAC Ambient Air Quality Standards.

21A