July 31, 2015

Amended August 5, 2015, August 6, 2015 and August 1 7, 2015

Memorandum to Docket ID # EPA-R08-OAR-2015-0493

Subject: Communication with State of Colorado regar ding discrepancies in SIP submittals

From: Jaslyn Dobrahner, Environmental Protection S pecialist Environmental Protection Agency, Region 8

On July 28, 2015, EPA and the State of Colorado dis cussed the following discrepancies with the state’s SIP submittal dated March 31, 2010 revising the Common Provisions Regulation:

• EPA noted that the last two sentences in the defini tion of “Incinerator” of the Common Provisions Regulation are not in the current SIP or marked as revisions in the March 31,

2010 submittal.

• Likewise, there are several compounds listed in the definition of “Negligibly Reactive Volatile Organic Compounds” (NRVOC) that are not in the current SIP or marked as revisions in March 31, 2010 submittal: (‘1, 1, 1, 2 , 2, 3, 3, -heptafluoro-3-methoxypropane’; ‘3-ethoxy-1, 1, 1, 2, 3, 4, 4, 5, 5, 6, 6 , 6-dodecafluoro2(trifluoromethyl)hexane’; ‘methyl formate’; and ‘1 , 1, 1, 2, 3, 3, 3-heptafluoropropane’)

• EPA also noted that there is a missing quotation ma rk in section I.B. and an incorrect abbreviation for microgram in section I.F. Both of these inconsistencies may alter the meaning of the regulatory language and cause confus ion.

In addition to the above discrepancies, EPA also re quested the state provide additional clarification on the following revisions from the M ay 16, 2012 and May 13, 2013 submittals revising Regulation Number 3, Part D:

• EPA asked why the state moved section II.A.26.d. to a new section at II.A.26.c.(iii)

• EPA also inquired as to why II.A.40.5. was deleted.

• In addition, EPA requested clarification on the int ent of the addition of text related to the

PM 2.5 surrogate policy found at VI.B.3.e.

On July 31, 2015, the state provided the following responses (via email):

• I.G. incinerator - Colorado adopted the two sentenc es at issue on 3/12/2004 as part of a Regulation 9 rulemaking. These revisions are included in Colorado's SIP submitted to EPA 7/21/2004, see attached.

• I.G. NRVOC - Colorado added these compounds on 12/1 7/2009 (SIP submittal to EPA dated 3/31/2010) to ensure consistency with the list contained in 40 CFR 51.100(s), which added the compounds on 11/29/2004.

• I.G. NRVOC (tertiary butyl acetate) - Colorado will consider making EPA's suggested revision in a future rulemaking.

• I.B. and I.F. - Colorado will consider making EPA's suggested revisions in a future rulemaking.Concerning your questions about Colorado's Regulati on 3 SIP:

• Part D, Section II.A.26.c.(iii) - this revision was a correction as, prior to the NSR Reform revisions and reorganization of Regulation 3 , this paragraph was under the "increase or decrease is credible" heading.

• Part D, Section II.A.40.5 - the definition of repre sentative actual annual emissions was deleted as part of Colorado's NSR Ref orm revisions. The entire definition was underlined in Regulation 3 for futur e deletion in 2004 but, due to a formatting issue, was only partially underlined b y the time Colorado was able to make those follow-up NSR revisions after EPA's a pproval of the NSR revisions in 2012. This definition also no longer e xists in 40 CFR Part 51.

• Part D, Section VI.B.3.e. - the January 13, 2011, l etter from the Division to EPA concerning the PM2.5 Surrogate Policy is attached.

Please let me know if you have additional questions about these submittals.

On August 5, 2015, Jaslyn Dobrahner, US EPA, called Leah Martland, Colorado Department of Public Health and Environment, to discuss Colorado’ s responses. From this call, the following

resolutions were made:

With respect to the state’s March 31, 2010 submitta l revising the Common Provisions Regulation, the state will provide to EPA:

• a request, with appropriate justification, to add t he last two sentences to the definition of “incinerator”;

• a request, with appropriate justification, to add s everal compounds to the definition of “NRVOC”; and

• a commitment to fix errors in I.B. and I.F.

With respect to the state’s May 16, 2012 and May 13 , 2013 submittals revising Regulation Number 3, Part D, EPA noted that the July 31, 2015 state response should be sufficient to proceed with acting on these submittals. No furthe r information is needed from the state at this

time.

On August 6, 2015, the state provided the following responses (via email):

As a follow up to our conversation concerning your review of Colorado's SIP Submittals #21, #126, and #182:

Colorado requests EPA approve the definition of NRV OC in Colorado's Common Provisions that includes "1,1,1,2,2,3,3,- heptaflur or-3-methoxy-propane; 3-ethoxy1,1,1,2,3,4,4,5,5,6,6,6-dodecafluror-2(trifluoromet hyl)hexane; methyl formate; and 1,1,1,2,3,3,3-heptafluroropropane." Colorado added these compounds to the definition of NRVOC on December 17, 2009, to ensure consistenc y with 40 CFR 51.100(s).

Colorado requests EPA approve the definition of Inc inerator in Colorado's Common Provisions that includes "Excludes devices commonly called Air Curtain Destructorsused exclusively to burn 100% wood waste, clean lum ber, or yard waste generated as a

result of projects to reduce the risk of wildfire a nd is not operated at a commercial or industrial facility. Any Air Curtain Destructor sub ject to 40 CFR Part 60 incinerator requirements is considered an incinerator." Colorad o added these two sentences to the definition of Incinerator on March 12, 2004, due to Colorado Regulation 9's use of the
definition and to address the use of air curtain de structors for burning materials generated as a result of projects conducted to redu ce the risk of wildfire.

Colorado will revise Colorado's Common Provisions S ection I.B. (add a missing quotation mark) and Section I.F. (correct the abbre viation for microgram) in a future rulemaking.

Please let me know if you have additional questions

.