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  • How do the different parts of particulate matter (PM) fit together?

    The various parts of PM in the NEI are related as follows. PM10-FIL > PM25-FIL because PM10-FIL includes PM25-FIL PM25-PRI = PM25-FIL + PM-CON This equation only applies at the process level. Because some sources only can report PM2.5 (due to test method differences), this equation does not apply to…

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  • How does PM2.5 relate to PM species such as EC, OC, SO4, NO3, PMFINE, and DIESEL-PM25?

    Primary PM2.5 estimates are speciated into the five PM species in the NEI: elemental (black) carbon (EC), organic carbon (OC), nitrate (NO3), sulfate (SO4), and the remainder of PM25-PRI (PMFINE). Diesel engine PM25-PRI and PM10 emissions are also labeled as DIESEL-PM25 and DIESEL-PM10 for mobile source diesel engines. For all…

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  • Visit and examination requirements for SPCC self-certification

    Pursuant to 40 CFR §112.6, the owner or operator of a facility that meets the criteria in §112.3(g) for either a Tier I or Tier II qualified facility may self-certify the facility's SPCC Plan. As part of the self-certification, the owner or operator must certify that he or she has…

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  • Availability of electronic SPCC Plan template

    Part 112, Appendix G to prepare an SPCC Plan. Is the Tier I qualified facility SPCC Plan template available in an electronic version? EPA has made available electronic versions of the Tier I qualified facility Plan template to help the owner or operator of a Tier I qualified facility develop…

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  • What is included in the emissions “Tiers”?

    The Tiers are assigned by a Source Classification Code (SCC), which has the most detail about the emissions processes that generate the emissions. The full list of SCCs, their associated Tiers, and the SCC descriptions is available online at https://ofmpub.epa.gov/sccwebservices/sccsearch/ .

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  • What does an annual emissions value in the NEI represent (one year or multiple years)?

    The NEI provides total annual emissions for a single year.

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  • Is formaldehyde a contaminant of concern from the derailment?

    Last week, an East Palestine resident reported to EPA that they had a skin reaction from handling soil in their backyard after digging a swimming pool. EPA tested the soil and did not detect high hazard chemicals. The device used for testing did indicate that low levels of formaldehyde might…

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  • What are the units of NEI emissions data?

    NEI emissions values represent total annual emissions for the inventory reporting year. Criteria air pollutants and precursors (CAPs) are reported in short tons per year , and hazardous air pollutants (HAPs) are reported in lbs per year .

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  • What is the definition of VOC?

    There is a regulatory definition of VOC. It is found in 40 CFR 51.100. CFR - code of federal regulations. The definition relates to the intent and requirements of the Clean Air Act. Excerpt from “Volatile Organic Compounds” Definition per 40 CFR Part 51.100(s): " Volatile organic compounds (VOC) means…

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  • What does "NEC" stand for in the emissions sectors?

    NEC means “not elsewhere classified” and includes SCCs that are not assigned to any of the other specific industrial process sectors. If you look at the SCC code table available at the SCC web site and filter on the Sector name that includes “NEC”, you can see the type of…

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  • Tier I qualified facility template use under Part 112

    In the 2008 Amendments to the SPCC Rule, EPA provided a template for the owner or operator of a Tier I qualified facility to create an SPCC Plan. Does EPA require a Tier I qualified facility to use the template in 40 CFR Part 112, Appendix G? Does EPA allow…

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  • Difference between an SPCC Tier I and Tier II qualified facility

    In the SPCC regulations in 40 CFR Part 112, what is the difference between a Tier I and Tier II qualified facility? How did EPA establish the multi-tiered approach for qualified facilities? A Tier II qualified facility is one that has an aggregate aboveground oil storage capacity of 10,000 U.S…

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