All4 tcc acit pres ipt guidance 2017

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Inter-Precursor Trading (IPT) Guidance

ALL4 Houston|281.937.7553 |all4inc.com30th Annual Environmental, Health & Safety Seminar

Galveston, Texas | June 5, 2017

Texas Chemical Council (TCC), Association of Chemical Industry of Texas (ACIT), Louisiana Chemical Association (LCA), Louisiana Chemical Industry Alliance (LCIA)

2 Your environmental compliance is clearly our business.

Click to edit Master title style Background IPT Guidance Ozone Formation and Tier 1 Approach Approach for Area Specific IPT Ratio Approach for case-by-case IPT Ratio Comparison with TCEQ’s IP/IB Guidance Case Study


Click to edit Master title style“the offset requirement for emissions of ozone

precursors NOX and VOC to be satisfied by offsetting reduction in emissions of either of those precursors…”

Federal Regulatory Drivers• 40 CFR 51, Subpart I, Section 51.165 (a)(11)(i) Permit

Requirements &• 40 CFR 51, Appendix S, Emission Offset Interpretative Ruling

State Regulatory Drivers• Texas – Title 30 Texas Administrative Code (TAC) §101.302(a)

and §101.372(a)• Louisiana – Title 33 Louisiana Administrative Code (LAC), Part III

§504.F (AQ354)

Background – Why?


Click to edit Master title styleBackground – Ozone Formationsunlight

VOC + NOX O3 (and other products)

No sunlight no ozone productionNo NOx no ozone productionNo VOC no ozone production


Click to edit Master title style VOC Limited – When hydroxide (OH) radicals

production is less than the rate of production of NOX,Ozone production is VOC limited.

NOX Limited – When rate of OH production is greaterthan the rate of production of NOX, indicating NOX inshort supply, Ozone production is NOX limited.

NOX Disbenefits – NOX emissions can lead to not onlyformation but sometime destruction of ozone, slowsthe ozone formation rate. NOX disbenefits isphenomenon where NOX emissions reductions canlead to ozone increases instead of decreases.

Background – Ozone Formation


Click to edit Master title style On October 04, 2016, U.S. EPA published draft

guidance document - “Technical Guidance forDemonstration of Inter-precursor Trading (IPT) forOzone in the Nonattainment New Source ReviewProgram”

Technical guidance for both air agencies and permitapplicants

Approach to establish an area specific ozone IPT ratio• Screening Approach• Refined Approach

Approach to establish a case-specific ozone IPT ratio• Tier 2 Refined Photochemical Modeling Approach

IPT Guidance


Click to edit Master title style Screening Approach

• Analysis of existing technically credible data Emissions inventory data Ambient monitoring data Meteorological data for area

• Establish Ozone Formation NOX limited area or VOC limited area

• If NOX Limited Offset ratio of 1:1 for NOX credits No VOC credit allowed

IPT Guidance – Area Specific IPT Ratio

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Click to edit Master title style Refined Approach

• Use of new or existing NOX and VOC single-source impactson downwind ozone assessment to estimate IPT ratio Existing relevant technical information such as air quality

modeling data for hypothetical industrial source can be used Depending on the size of the original study, this can be only

developed for a sub-area The use of pre-existing credible information for this purpose will

be done by air agencies in consultation with EPA• Comparability analysis

Includes average and peak temperatures, humidity, terrain, ruralor urban nature, nearby regional sources, and ambientconcentration profiles

• EPA’s MERP Guidance can be used

IPT Guidance – Area Specific IPT Ratio


Click to edit Master title style Permit applicant may choose to NOT rely on the air

agency’s default ozone IPT ratio Case Specific IPT ratio allows permit applicant to

develop robust IPT ratio applicable to the projectspecific circumstances

Case Specific Approach• Consult with agencies and prepare protocol• Conduct photochemical gird modeling for post-project

emissions increases and credit sources and compareimpacts

• Submit modeling report and modeling files• Get approval from State air agency and EPA

IPT Guidance – Case Specific IPT Ratio


Click to edit Master title stylePhotochemical Models

Photochemical models are numerical models that simulate the emission, chemical transformation, transport, and deposition of gases and aerosols

Gases and Aerosols

Emissions

Chemical TransformationTransport

Deposition


Click to edit Master title stylePhotochemical Models


Click to edit Master title styleCAMx – Photochemical Grid Model

Figure from: CAMx User’s Guide Version 6.0, Environ, May 2013: Pg. 7.


Click to edit Master title style Identify the location of the project source (VOC

increases) and relevant credit source (NOX decreases) Model the project source and credit source(s) using

appropriate model (CAMx) to develop modeledOzone impacts from precursors

Compare the modeled results• All modeled impacts in grid cells within nonattainment

area with elevated ozone prediction• Use NAAQS relevant averaging period – daily maximum 8-

hr average• Discard the negative impacts (i.e. project impact > credit)• Hourly ozone impacts summed over all grid cells in the

area• Impacts from VOC and NOX compared to daily IPT ratios



Click to edit Master title style Calculate IPT Ratio are calculated as the product

of the “relative change in emissions” and the“relative change in the modeled ambient O3 levelsdue to precursors• NOX emissions increases offset by VOC credits

Ratio of 𝑁𝑁𝑁𝑁𝑁𝑁:𝑉𝑉𝑁𝑁𝑉𝑉 = 𝑁𝑁𝑁𝑁𝑁𝑁 𝑡𝑡𝑡𝑡𝑡𝑡𝑉𝑉𝑁𝑁𝑉𝑉 (𝑡𝑡𝑡𝑡𝑡𝑡)

∗ 𝑁𝑁𝑂 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑁𝑁𝑁𝑁𝑁𝑁 𝑡𝑡𝑡𝑡𝑝𝑝𝑁𝑁𝑂 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑉𝑉𝑁𝑁𝑉𝑉 𝑡𝑡𝑡𝑡𝑝𝑝

• VOC emission increases offset by NOX credits

Ratio of 𝑉𝑉𝑁𝑁𝑉𝑉:𝑁𝑁𝑁𝑁𝑁𝑁 = 𝑉𝑉𝑁𝑁𝑉𝑉 𝑡𝑡𝑡𝑡𝑡𝑡𝑁𝑁𝑁𝑁𝑁𝑁 (𝑡𝑡𝑡𝑡𝑡𝑡)

∗ 𝑁𝑁𝑂 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑉𝑉𝑁𝑁𝑉𝑉 𝑡𝑡𝑡𝑡𝑝𝑝𝑁𝑁𝑂 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑁𝑁𝑁𝑁𝑁𝑁 𝑡𝑡𝑡𝑡𝑝𝑝



Click to edit Master title styleEPA’s IPT Guidance

IPT guidance is optional andincludes Tier 1 & 2 approaches

IPT is guidance is case-by-caseand subject to agency approvals

IPT ratio calculation may requiremultiple modeling runs fordifferent scenarios

Credit source(s) modeled atcredit source location

Analysis of the entire basin andall grid cells in the domain isrequired

Maximum daily day-by-dayimpact evaluation is required

IPT vs Inter-pollutant (IP)TCEQ’s IP Guidance

IP guidance is mandatory forpermit applicants

IP guidance provides a detailedprocedure for modeling

IP ratio calculation is morestraightforward and depends onthe impact

Credit(s) modeled within 1 kmcircle from the project sourcelocation

Analysis of only grid cells withhigh ozone impact is required

Analysis of ozone monitorswithin the nonattainment area isrequired


Click to edit Master title style Hypothetical Industrial Facility located in the

Houston-Galveston-Brazoria (HGB) area Typical industrial facility with petrochemical/refinery

source profile• Industrial boilers• Engines• Catalytic cracking units• Tank farm• Polymerization and Alkylation Units etc.

Project – VOC emissions increase of ~ 145 tpy Credit – NOX emissions credits

• Option 1 – Control existing boilers• Option 2 – Utilize existing ERC

Case Study - Project


Click to edit Master title styleEPA’s IPT Guidance

Option 1• IPT Ratio

VOC:NOX = 1:1 Actual ratio 1:0.55

Option 2• IPT Ratio

VOC:NOX = 1:3.47

Case Study - ResultsTCEQ’s IP Guidance

Option 1• Overall Air Quality

VOC:NOX = 1:1 Actual ratio 1:0.28

• Design Value AnalysisVOC: NOX = 1:**

Option 2• Same as above


Click to edit Master title styleOption 2 – Credit source

at Project LocationOption 1 – Credit source

at Project Location

Case Study - Results

Monitor 3

Monitor 2

O3 Titration

Monitor 1

Project

O3 Formation

Credit

O3 Titration

Monitor 1

Source

O3 Formation

Monitor 2

Monitor 3

Credit


Click to edit Master title style IPT Guidance provides technical guidance to establish area

specific as well as case-by-case specific IPT ratio Depending on the project situation, the IPT ratio can vary

significantly – different atmospheric conditions can influenceprecursor potential of ozone formation

EPA’s IPT and TCEQ’s IP Guidance document difference inseveral aspects

Differences in the guidance can impact project timeline andoutcome

Be aware of unique situations like NOX Disbenefits If you have an upcoming project

• Plan ahead and understand your facility profile Understand the VOC speciation Understand the Credit sources

• Complete some fatal flaw analysis• Engage agency earlier in the process (if possible)

Conclusions

Q&A and Discussion

Thank You !!!