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E-Enterprise for the Environment

Combined Air Emissions Reporting Minimum Viable Product FAQs

(As of March 2020)

  1. The Common Emissions Form (CEF)
  2. Working with the CEF
  3. Bulk uploads/downloads
  4. Quality Assurance and Control
  5. Integration with the Toxics Release Inventory via TRI-MEweb
  6. Georgia Pilot and MVP
  7. Information Technology
  8. Funding and Onboarding Support

The Common Emissions Form (CEF)

  1. Can I take advantage of the Common Emissions Form (CEF) and still keep my State, Local, Tribal Authority (SLT) reporting system?

    Yes.  For the minimum viable product (MVP) we are building one workflow for states that don’t have a system or that don’t wish to keep their current systems.  However, we have anticipated that there may be many workflows in the future.  Depending on the SLTs needs and preferences, we will build out more workflows with the CEF so that it can be used either to send or receive data from your custom system or SLEIS.

  2. Can a facility use this form for Toxics Release Inventory (TRI)/Greenhouse Gas reporting program (GHG RP) even if their state does not participate?

    Ideally, we’d like to work with the SLT.  While currently we only have built out the NEI and TRI part of the workflow, it would be possible for the facility to report to the federal programs, except for NEI, irrespective of the state once we have incorporated the other federal programs to the CEF.  However, doing so would decrease a significant benefit of the use of the CEF and we would encourage facilities to reach out to their state to express interest in using the CEF.

  3. What about Confidential Business Information (CBI)?

    One of our PDT R&D teams researched CBI, and found that SLTs determine what can be considered CBI, and also, how the CBI is sent to them outside of the reporting system.  For example, the SLT would accept a more generic submission but ask the facility to send details of the calculations outside the CEF.  We would work with the SLT to find the best way to handle CBI.

  4. Will states be obligated to use the CEF?

    A state may opt-in to the CEF if they would like to.  We hope to create a product that users will want to use, but it will not be mandatory.

  5. Are there any plans to let facilities opt out of TRI and GHG reporting if they report this data as part of the National Emissions Inventory (NEI)?

    There are no plans to change the Toxics Release Inventory (TRI) or Greenhouse Gas Reporting Rule (GHGRP) to allow for “opt out” of those rules.  The goal of the CEF is to enable the facility to enter their data a minimum number of times to report to all the programs.  For example, for TRI reporting, the CEF will allow for the automatic transfer of state/NEI reported emissions to pre-populate the air emissions portion of the TRI online form, so that very little additional effort for air reporting for TRI would be needed.

  6. What type of reporting are you looking at when mentioning GHG? Are you looking at utilizing this for Part 98 reporting instead of e-GGRT?

    We are referring to the Greenhouse Gas Reporting Program (GHG RP).  The CEF would not substitute its reporting system, the electronic greenhouse gas reporting tool (e-GGRT), but allow flow of data between itself and e-GGRT so that data that was input to one would prepopulate the other.  It is early in the development process and we are interested to hear feedback on what set up in the CEF would best allow facilities to report their NEI and GHG emissions in a more streamlined way.

  7. Can supplemental information be submitted with the CEF such as pdf files or excel spreadsheets?

    Yes, we are planning to allow the facility to attach supplemental information as needed and as the SLT and programs allow.  There will also be comment boxes in the user interface for simple text explanations.

  8. Will use of the CEF be mandatory?

    No, the adoption of working with the CEF is voluntary, but we hope you will consider it.  Your input will help us make it a better product for industry and SLTs.  Working with EPA, you’ll be able to customize the CEF to your needs.

  9. Will the use of the CEF replace the other systems like the Emissions Inventory System (EIS) and Toxics Release Inventory Made Easy Web (TRI-MEweb) and the SLT system?  How does the data entry trickle down to the program reports?

    At this time, it is not contemplated that these systems will be changed or replaced.  The CEF will serve as an entry point for all the data to be delivered or picked up by the other systems.  In the future, it is possible that data entered to another system will be used to prepopulate the CEF as well.  As we integrate with the other systems, we will assess options and request feedback from industry on how best to do the integration with the other system.  Your suggestions on how we can achieve this are very helpful.

  10. What if I am a facility not in GA but I want to participate in pilot testing?

    Please reach out to your state and ask them to join the CEF effort.

  11. What should I do if I have input for the development of the CEF?

    If you have more questions, or user stories, please send them to  Your user stories will help us understand what the CEF needs to do to be effective for your use as an SLT or industry reporter.  User stories are most helpful when they are in the following format:  I am a ___________ (role, e.g. reporter, certifier, SLT reviewer), and I need the CEF to ____________________ (what you need to see in the CEF or have it do, e.g. show a facility summary by total emissions, do a bulk upload), so that I can_________________ (e.g. see which facilities have the highest emissions that I need to review so that I can understand if there was an entry error, upload data for 5 facilities that have about 100 units each without having to enter each unit individually).

Working with the CEF

  1. Are control devices in a serial configuration accommodated? How will complex controls be handled?

    Controls in series and parallel will ultimately be accommodated by the CEF.  The new way of configuring controls is under development for the Emissions Inventory System for National Emissions Inventory reporting.  This configuration will be matched by the CEF.  Once the new set up is in place, trainings will be provided to give facilities and SLTs ample opportunity to learn and adjust to the new set up.  Many SLTs already handle complex controls in their systems and the transition should be easy for them.

  2. Production information is not required for several of these rules, just an emission rate.  Will this form add this requirement?  Can you enter emission rates, instead of factors times production?

    Eventually all types of "calculation methods" whether they require activity data or entry of an emission rate will be included in the CEF.  You would select “stack test” emissions calculation method to submit your rates, e.g.

  3. What if my SLT has different field names for reporting than some of the programs?

    The CEF will contain a glossary so that an explanation of field names will be available to the user.  Furthermore, as we work with the SLTs, we will be able to create crosswalks between SLT data fields and federal program data fields to ensure the correct data meaning is being conveyed and the right data fields are being captured.

  4. Will the form handle pollutant groups?  For instance, check that the sum of individual volatile organic compound (VOC) Hazardous Air Pollutants (HAPS) don't exceed the reported VOCs.

    There will be QA checks to help the user know if individual pollutant additions are exceeding a total.  For MVP we have some basic QA checks, such as all checks that EIS currently uses on SLT point source data submitted to EPA, and many QA checks that states on our Product Design Team asked for. Over time, we hope to have more sophisticated QA checks in place to help the user with pollutant groups, e.g. HAP/VOC HAP checks.

  5. What emission factors will be in the CEF for us to use?

    There will be emission factors by SCC from WebFIRE and there will be emission factors from your SLT.  In addition, some states have augmented their own list of emission factors and if the state your facility is in allows, you will be able to use those other state factors for your submissions.

  6. Can you have emission factors that use different units of measure (UOM)? For example, for a boiler: an emission factor for NOx on the basis of hours, and an emission factor for CO on the basis of gallons of Fuel Oil?  Would you have to have a separate process for "hours" UOM?  Could we have multiple throughputs for one process?  For example, when emission factors are from a performance test, the throughput could be operation hours.  This may be different from other throughput, such as coal.

    We are working to include this option in the CEF.  Because there are many SCCs and types of units of measures for emission factors, we are working to include the most common use cases (pairings of UOM such as hours and fuel used, e.g.) first, and then will continue to build out more options for reporters.

  7. Do you plan to add the ability to compare hours of operation for an emission unit for two or more years to the common form?  We have found it useful to see previous year's throughput to compare to current year's throughput.  Do you plan to add this capability for the SLT reviewer?

    We will be adding the ability for the SLT to generate reports in the CEF in multiple ways.  For the MVP the SLT will be able to compare the current inventory year submission with the previous submission the facility made.  Your input on how SLTs and users would find the set-up of such comparisons most useful would be very helpful at this time.

  8. Any consideration for a process emission summary that provides emission calculation method, emission factor, and control for each pollutant?

    This could be an additional type of screen or report that we could add the CEF.

  9. Will the emission factors selected/entered be saved year to year?

    Data from a previous year will be pre-populated in the user interface and the template.  However, to the degree that your state expects the emission factor you entered in a previous year to have changed, you would have to enter a new emission factor as appropriate.  Your state would be able to tell you which kinds of factors carry over year to year and which they expect would change.  In addition, you’d want to check for retired SCCs to make sure your emission factors are not for an SCC that was retired in a previous inventory year.

Bulk uploads/downloads

  1. I report many facilities and entering one at a time would still be time consuming. Will there be bulk upload or bulk entry?

    Bulk upload is a feature that is being built into the CEF MVP.  Bulk upload will be possible in two ways.  One, via an excel template whereby the facility will fill in the template and submit it to the CEF.  The second, a facility may choose to send the file in the correct format directly to the CEF from its own system.  Details on the template format will be released in Spring of 2020.  While GA facilities will be reporting in the CEF first, we hope that releasing the information about the template will help facilities from future onboarding states to prepare for future reporting via the CEF.

  2. Will there be an option to download the previous year's data into the current year as a starting point?  This saves a lot of time.  Emissions form a stack test or a rate, for example.

    Yes, previous year submissions will show up for the user in the user interface.  Also, we are working on having a “bulk download” of the template prepopulated with previous year data to make updates easier for the user.  Note that a previous year submission should not be resubmitted as a current year submission, though.  The SLT will expect the facility to have updated the relevant activity data, emission factors and rates, e.g.

  3. For initial setup, will there be a backend XML our spreadsheet upload option?  My facility has many release points and pollutant combinations.

    We won’t have an XML file but will be able to receive an Excel spreadsheet and/or a JSON file.  We will publish the templates ahead of time so facilities can familiarize themselves with the set up.

Quality Assurance and Control

  1. What Quality Assurance (QA) checks will the CEF perform?

    The CEF will perform checks both in the user interface as data is entered, and at the end before the data is submitted (this includes QA on bulk uploaded data).  The QA checks are checks that will allow for catching errors and inconsistencies in data entered (e.g. having an address with a viable zip code, making sure that throughput units of measure are compatible with emission factor units of measure).  These include QA checks the SLT may want in addition, such as making sure a previous year submission is not identical to a current year submission, that emissions are reasonable within a threshold or tolerance for a specific type of equipment.

  2. When does the information go to EPA?  Can EPA conduct QA at the same time as the SLT?

    In the case of NEI data, the SLT will review the data before submission to EPA.  This ensures that the facility and the SLT can work out any edits needed to the submission.  While data for TRI is independent from SLT review, to the degree that the facility can wait to submit its TRI data after the SLT review of its NEI data, this will ensure more consistency in the submission of its data for both programs.  The SLT will submit data to NEI as per the regular deadlines, so the facility will work with their state to meet the deadlines.  TRI-MEweb will pick up the hazardous air data with enough time to meet the TRI deadline.

  3. Will there be a QA check that checks that SCC is sensible for the throughput type?

    The CEF will have some basic QA checks.  It will alert the user if the emission factor selected for an SCC is in different units as the throughput so that the user can make an adjustment accordingly.

Integration with the Toxics Release Inventory via TRI-MEweb

  1. TRI has other information that isn't air emissions. How will other information be merged to this and properly integrated into each individual chemical reporting sheet and ensure it is applied properly?

    The reporter will report air emissions to the state for NEI via the CEF.  Any air toxics data that the reporter includes in the CEF will be rolled up to the facility level and prepared for TRI-MEweb to pick up.  The reporter will then open TRI-ME web and have the option to use the data reported in the CEF, to prepopulate air emissions reports in TRI-MEweb.  Then the reporter will continue to report its emissions for other media in TRI.

  2. Some of the emissions in TRI are not identical to those that can be reported to NEI, e.g. many are related, but not exactly the same.  How will this be handled?

    For MVP the facility will be able to select the relevant pollutants from a list of pollutants.  Post MVP the nuances in the programs where some toxics are handled differently in TRI than NEI will be incorporated to make reporting easier for the user.  One of our Product Design Research and Development Teams has created the relevant crosswalks that we will be incorporating into the CEF.  Refer to the CAER website and work by the product design teams for more information.

  3. Some states require reporting of pollutants in different ways than others.  E.g. some states require flat VOC versus sum of mass.  How will the CEF handle the need to report these differently?

    As different states onboard, the CEF will be customized to accommodate specific state needs.  If one state has specific requirements that are slightly different than another’s the CEF will allow the reporter to enter the “raw activity data” as needed, and then perform the relevant calculations using the method each state and program requires.

  4. NEI requires sub-facility level data reporting, but TRI is at a facility total.  How will the CEF handle this?

    The goal is for the facility to be able to enter all its “input” data, i.e. the data that is used for all calculations, and the CEF will aggregate the data going to TRI for the facility.  In this way, the facility can take advantage of the calculator in the CEF.  Any sub-facility data used for calculations that is not required by NEI or TRI will not be carried forward to the programs, only the data required will do so.

  5. How will you handle cases where TRI air emissions don't get reported to NEI?

    The facility has the option to use the CEF to calculate all air toxics emissions and the CEF will add them up for TRI pick up.  Doing the data entry this way will help ensure consistency in reported data between data reported to the state for NEI and TRI data, even if the programs require data at different levels of detail (i.e. overall activity data generating the reported pollutants would be consistent even for different pollutants).  If there are emissions that the facility doesn’t wish to enter in the CEF, it would then enter them directly into TRI-MEweb.

  6. How does the system find the correct TRI form and update data?  Is there a way to distinguish between TRI and NEI data?

    There is not currently a way to distinguish between TRI and NEI data within the Common Form except by looking at the individual pollutants.  For MVP, the facility will have to select and report the relevant pollutants for NEI and TRI.  The form calculates the TRI emissions from units and adds them up to the facility level.  TRI-MEweb picks up the totals.  In future, the CEF will have more sophistication so that some pollutants both for NEI and TRI can be derived from others being reported.  Your input on how the CEF could be set up to show the users what they will need to do to accomplish this are very welcome at this time.

Georgia Pilot and MVP

  1. How can I find out more information about the Georgia pilot facilities, or work as a pilot facility in Georgia (GA)?

    Please contact your SLT representative at GA DNR, Jing Wang ( for more details.

  2. If this expected to be rolled out in June 2020, and Georgia emissions statements and inventories are due in mid-late June, will we be expected to use GECO or CAER for Georgia emissions reporting for RY 2019?

    For specific questions about reporting to GA, please reach out to your point of contact in GA DNR, Jing Wang (

  3. How much will the software for the CEF cost?

    The use of the Common Form application will be free in that it will only require you to have a recent version of a web browser such as Chrome, Firefox, or Explorer.

Information Technology

  1. Will the application be open source (e.g. Github)?

    At this time the source code is not open source.

  2. What is the architecture in the background that supports the CEF.  Webservices?

    We are using REST Web Services for all new functionality.  We are using existing EPA services as well (e.g. SCC Registry, CDX authentication).

Funding and Onboarding Support

  1. How do I know if my SLT is interested in participating in the CEF?

    You should reach out to them to ask for their interest and express yours.

  2. As an SLT, what is my next step if I am interested in onboarding to the CEF?

    We have published a roadmap document that illustrates the steps we’d follow to have your state use the CEF.  You can also reach out to Julia Gamas ( with questions.  We can have some discussions where we can learn how your state reports now, what aspects of your current reporting you’d like to keep, and what aspects you’d want to improve.  We’d then look at next steps from there.

  3. As an SLT, where can I find information about financial help to onboard as a CAER CEF user?

    Look for the Exchange Network Grants published here:  You can also reach out to ECOS to find out what kind of assistance might be available (Kelly Poole,

  4. If my SLT onboards, what kind of support will my use of the CEF have moving forward? Will EPA continue funding CAER and/or supporting future CEF development?

    EPA is committed to making CAER and the CAER system work for everyone who onboards. Once a version of the CAER system is in operation, that version will continue to be funded under “operations and maintenance” (O&M). O&M activities for critical infrastructure like CAER have always been funded by EPA in the past, even in times of reduced budgets. This means that any state that has already been onboarded will be able to continue to use the CAER system. As funds are available for improvements and enhancements, then additional features can be added.

    The CAER system approach also offers a number of advantages over maintaining your own system. For example, because the CAER system built in flexibilities, features that already work for one SLT can be adopted by another SLT at any time as part of system configuration under O&M. In addition, EPA is committed to ensuring the CAER System meets EPA reporting requirements now and in the future, even if those change. The CAER System will always be integrated with the latest reporting codes (e.g., source classification codes), emissions factors, pollutant codes, and other data elements that may change over time. Furthermore, future expansion of E-Enterprise intends to connect emissions inventory to electronic permitting, provided that resources are available.