Tracking Michigan Air Toxics Program Applicability Using MON Operating Scenarios MCC Annual Conference October 17, 2017 Steve Zervas, Managing Consultant David Dempsey, Managing Consultant
Meaningful Change Exemption for Air Toxics
Background ˃ MDEQ introduced the terms “ Meaningful Change ” and “ Meaningful Increase ” with its PTI exemption rules published in 1992. ˃ The concepts for determining whether a change or increase is meaningful was presented as guidance in 1993. ˃ The terms were defined in the regulations in December 2016. ˃ Written guidance on implementing the concepts was published in May 2017.
What does the Meaningful Change Exemption do? ˃ Allows process changes without permitting ˃ Based on evaluation of baseline Toxic Air Contaminant (TAC) emissions and post-change TAC emissions ˃ Relies on a concept called the Hazard Potential ˃ Baseline established using potential emissions included in an approved application dated after April 17, 1992
Hazard Potential Two Hazard Potentials are required to make a Meaningful Change determination – one for carcinogens and another for non-carcinogens. The Hazard Potential is Calculated as follows: Hazard Potential = PTE (lb/hr) / IRSL or Adjusted Annual ITSL The adjusted annual ITSL is the ITSL adjusted to an annual averaging time. To convert from: 1-Hr to Annual: multiply ITSL x 0.10 8-Hr to Annual: multiply ITSL x 0.11 24-Hr to Annual: multiply ITSL x 0.17
Meaningful Change ˃ A change that increases Hazard Potential more than 10% is a Meaningful Change. ˃ To determine the increase, compare the baseline carcinogenic Hazard Potential with the post- change carcinogenic Hazard Potential. Likewise for the non-carcinogenic Hazard Potentials. ˃ If there is no baseline Hazard Potential, the post- change Hazard Potential (of the same type) represents more than a 10 percent increase.
Seven Step Process Identify the TACs for both the existing permitted emission unit and 1. the emission unit after the proposed change. Determine the hourly potential to emit (PTE) in pounds per hour for 2. each TAC. PTE is defined in Rule 116(m). Identify all screening levels (SLs) for each TAC identified in Step 1. 3. Some TACs have both an ITSL and an IRSL – both must be used. Convert each non-annual ITSL to adjusted annual ITSL. 4. Calculate both a carcinogenic Hazard Potential (HP) and a non- 5. carcinogenic HP for each SL. HP = (hourly PTE) / (IRSL or adjusted annual ITSL) Find the highest HP for non-cancer (based on ITSLs) and the highest 6. HP for cancer (based on IRSLs) for both the existing operation and post-modification. Determine the percent change in each HP - an increase of more than 7. 10% in either HP is “meaningful”.
Other Considerations Changes cannot involve the installation or reconstruction of an ˃ Emission Unit Changes cannot result in emissions greater than an existing permit ˃ limit Some Meaningful Changes may be exempt – Rule 285(2)(c)(iii) ˃ Meaningful Increase: ˃ MDEQ Policy: Emissions increases of greater than 10% are not meaningful if they � don’t cause an increase in the Hazard Potential of more than 10% MDEQ Rule: Meaningful Increase means an increase of 10% or more of an � individual TAC (e.g., of the same TAC, or any new TAC not in the baseline) Installation of control equipment may utilize this approach ˃ If a proposed change involves a TAC without a SL, it must be included ˃ – use regulatory guidance to develop an appropriate SL. Maintain records for each Meaningful Change evaluation performed ˃
Example 1 A facility obtained a permit in 1999 that included a 10 lb/hr emission limit for Compound A. No changes have occurred at the facility since then. The proposed change will increase Compound A to 12 lb/hr. Since the original permit was obtained, the ITSL for Compound A has increased from 1,200 µg/m 3 (annual) to 5,000 µg/m 3 (annual). PTE IRSL ITSL Averaging Adjusted Hazard TAC (µg/m 3 ) (µg/m 3 ) (lb/hr) Period Annual ITSL Potential Baseline: 10 --- 1,200 Annual --- 0.083 Compound A Proposed: 12 --- 5,000 Annual --- 0.002 Compound A Evaluation: Even though the Hazard Potential decreases, this project cannot be exempt because the new emission rate will exceed an existing permit limit.
Example 2 A facility obtained a permit in 2010 that included a carcinogen and two non- carcinogens. The proposed change includes 3 carcinogens and 17 non- carcinogens. PTE IRSL ITSL Averaging Adjusted Hazard TAC (µg/m 3 ) (µg/m 3 ) (lb/hr) Period Annual ITSL Potential Baseline: 1.1 1.2 --- Annual --- 0.917 Carc A 0.55 --- 6,000 24-Hr 1,020 0.00054 Non-Carc A 16.2 --- 17 1-Hr 1.7 9.53 Non-Carc B Proposed (only the worst-case listed here): 0.6 0.8 --- Annual --- 0.75 Carc B 12 --- 10.5 8-Hr 1.16 10.34 Non-Carc G Evaluation: Carcinogenic HP decreases from 0.917 to 0.75 – not Meaningful Change. Non-Carcinogenic HP increases from 9.53 to 10.34 = 8.5% increase – not Meaningful Change.
Example 3 A facility obtained a permit in 2007 that included one carcinogen. The proposed change includes 2 non-carcinogens. PTE IRSL ITSL Averaging Adjusted Hazard TAC (µg/m 3 ) (µg/m 3 ) (lb/hr) Period Annual ITSL Potential Baseline: 65 1.2 --- Annual --- 54.17 Carc A Proposed: 15 --- 1,000 24-Hr 170 0.088 Non-Carc X 35 --- 5,000 8-Hr 550 0.064 Non-Carc Y Evaluation: There is no baseline non-carcinogenic Hazard Potential. Therefore, no Meaningful Change calculation can be made. This project cannot be exempt.
Operating Scenario Records – The MON and TAC Additions
MON Summary ˃ 40 CFR 63, Subpart FFFF - Miscellaneous Organic NESHAP ˃ EPA’s catch-all rule for chemical manufacturing sources not subject to another NESHAP ˃ Intended to be flexible – cover many different types of chemical processes � More site-specific applicability determinations than typical MACTs ˃ Contains detailed operating scenario and process change recordkeeping and reporting requirements
DD2 Operating Scenarios ˃ MON Final Rule Preamble …Our position is that submitting operating scenarios is critical to enforcement of the final rule, as they provide much of the information required to demonstrate compliance. Information in operating scenarios also is the cornerstone of the management of change strategy that was developed to address the constantly changing processing environment associated with batch processors. Although this management of change flexibility is optional at the discretion of the regulatory authority, 40 CFR part 63, subpart FFFF, provides the framework for implementing the strategy.
Slide 14 DD2 in other words, the MON provides an example of a well-described management of change procedure for evalating facility changes that could be applied for NSR. David Dempsey, 7/22/2015
MON Operating Scenario Records ˃ Process/equipment description ˃ Identify process vents and associated emission episodes ˃ Identify support operation � Wastewater, storage tanks, transfer racks ˃ Calculations and engineering analyses required to demonstrate compliance
MON Operating Scenario Records ˃ Applicable control requirements, including level of control ˃ Control device details � Description � Identify all equipment routed � Description of operating conditions � Description of testing conditions � Monitoring requirements � Monitoring levels that assure compliance
Your Operating Scenario? ˃ For each process line - � What products do you manufacture? � Are there multiple formulations for a product? Different solvents used? � Different TAC composition ˃ Documentation needed for each operating scenario will vary � Is one product clearly the worst case HP? � How many products do you need to have the HP (i.e., what is reasonable)
Operating Scenario Baseline Records for TAC ˃ Have records by process and product ˃ Identify each air toxic contaminant ˃ For each air toxic contaminant � IRSL or adjusted annual ITSL � baseline PTE established by either ♦ the permit limits after April 17, 1992 ♦ the permit application � Hazard Potential (HP) ♦ Carcinogens ♦ Non-Carcinogen � Assumptions that affect PTE and HP
Operating Scenario Project Records for TAC ˃ Have records by process and product ˃ Identify each TAC affected and each new TAC ˃ For each TAC � IRSL or adjusted annual ITSL � PTE � Hazard Potential (HP) for each TAC ˃ Compare max HP to baseline � Carcinogens � Non-Carcinogens
Watch Out!! ˃ Accurate calculation of lb/hr emissions � Not average annualized ˃ Have records by process and product � Products with TAC not worst-case for permitting purposes � Tracking multiple products with TAC ˃ TAC not previously used ˃ Changes in screening levels ˃ Do you have records of past applications?
Key Baseline Records ˃ Have records by process and product ˃ Identify each air toxic contaminant ˃ For each air toxic contaminant � IRSL or adjusted annual ITSL � baseline PTE established by either ♦ the permit limits established after April 17, 1992 ♦ the permit application or facility records � Hazard Potential (HP)
Questions/Follow-up Discussion Steve Zervas 734.474.7709 szervas@trinityconsultants.com David Dempsey Chemical Sector Services 630.495.1470 ddempsey@trinityconsultants.com
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