This page provides step-by-step instructions on how to enter and edit Subpart Y Petroleum Refinery CO₂ emissions information for process units that are monitored by a Continuous Emissions Monitoring System (CEMS).

This page applies to the following types of process units that may be monitored by CEMS under Subpart Y:

• Coke calcining units
• Catalytic cracking units
• Traditional fluid coking units
• Fluid coking units with flexicoking design
• Catalytic reforming units
• Sulfur recovery plants

Step 1: Add a CEMS Monitoring Location (CML)

To add a CML, click the “Add a CEMS Monitoring Location” link below the CEMS MONITORING LOCATION (CML) SUMMARY table on the Subpart Overview page

Click this link to expand

Step 2: Define a CML and report emissions information

For each CEMS Monitoring Location, provide the following information:

• A unique unit name or identifier for the CML (see also About Unique Unit Names)
• An optional description or label for the CML
• The configuration of processes or process units that are monitored by the CML:
  • Single process or process unit that exhausts to a dedicated stack
  • Multiple processes or process units that share a common stack
  • Process or process unit that shares a common stack with one or more stationary fuel combustion units
• The types of fuel combusted in the unit(s) monitored by the CEMS
• The Tier 4/CEMS methodology start and end dates
• The total hourly CO₂ mass emissions for each quarter of the reporting year (metric tons) (Do not cumulate emissions data between quarters)
• The total annual CO₂ mass emissions measured by the CEMS (metric tons)(This is the sum of the four quarterly totals)
• An indication whether emissions reported for the CEMS include emissions calculated according to 98.33(a)(4)(viii) for a slipstream that bypassed the CEMS
• The total annual biogenic CO₂ emissions from the combustion of all biomass fuels combined (metric tons) (if not applicable, enter '0')
• The total annual non-biogenic CO₂ emissions which includes fossil fuel, sorbent, and process CO₂ emissions (metric tons)
• The total annual CH₄ and N₂O emissions associated with the combustion of all Table C-2 fuels combusted in all processes/process units monitored by the CEMS derived from application of Equation C-10 (metric tons) (if there are no combustion emissions in this CML, please enter '0')
• The total number of source operating hours in the reporting year
• The total operating hours in which a substitute data value was used in the emissions calculations for the CO₂ concentration parameter
• The total operating hours in which a substitute data value was used in the emissions calculations for the stack gas flow rate parameter
• If moisture correction is required and a continuous moisture monitor is used, the total operating hours in which a substitute data value was used in the emissions calculations for the stack gas moisture content parameter
• The total annual CO₂ emissions from the CEMS Monitoring Location (CML) Summary attributable to combustion (metric tons)

Do not leave any of these fields blank. If, for example, your facility has no biogenic CO₂ emissions, enter '0'.

For assistance in calculating annual CH₄ and N₂O emissions using Equation C-10, access the optional calculation spreadsheet by clicking one of the links titled “Use Equation C-10 spreadsheet to calculate” located below each of the red emissions information data entry boxes and follow the provided instructions

Step 3: Identify process units monitored at a CML

To identify the process units monitored at a CML, first click the link titled “ADD/REMOVE a process unit that exhausts to this CEMS Monitoring Location” at the bottom of the page

Click this link to expand

 

On the CML Process Units Selection page, use the check boxes to select the process unit(s) monitored at this CML. This will indicate that the unit(s) selected vent emission through the stack monitored by this CML.

Click this link to expand

 

When finished selecting process unit for the CML and entering additional required information (if applicable), click SAVE. You should then be directed back to the Add/Edit a CML Location form and see the units you selected listed in the CEMS MONITORING LOCATION (CML) PROCESS UNITS table.

Step 4: Save entered data for a CML

When you have finished entering data for a CML, click SAVE. You will then return to the Subpart Overview page. You will see the status of data entry for the CML updated to “Complete” in the Status column in the CEMS MONITORING LOCATION (CML) SUMMARY table.

If you don't have all the data, you can enter some now, save it, and finish later by clicking on the hyperlinked name of the CML in the CEMS MONITORING LOCATION (CML) SUMMARY table.

After you save the data on this page, the next time you open the page, the calculator on the top of the page will display the CO₂ process emissions for the CML, rounded to the nearest 0.1 of a metric ton. The value displayed is for informational purposes only.

Step 5: Repeat Steps 1-4

Repeat Steps 1-4 until emissions information has been entered for all CMLs. If you have missed something, the validation report messages will help you identify any incomplete entries.

Back to Top

See Also

Screen Code
Using e-GGRT to Prepare Your Subpart Y Report

• Subpart Y Summary Information for this Facility
• Subpart Y Asphalt Blowing Unit Information for RY2018 and Later Years
• Subpart Y Delayed Coking Unit Information
• Subpart Y Asphalt Blowing Unit Information
• Subpart Y Asphalt Blowing Unit Information for RY2014 - RY2017
• Subpart Y Coke Calcining Unit Information
• Subpart Y Catalytic Cracking, Fluid Coking, and Catalytic Reforming Unit Information
• Subpart Y Delayed Coking Unit Information for RY2018 and Later Years
• Subpart Y Delayed Coking Unit Information for RY2014 - RY2017
• Subpart Y Flares Unit Information
• Subpart Y On-Site Sulfur Recovery Plant Information
• Subpart Y Process Vents Unit Information
• Subpart Y Emissions Information for Process Units Monitored by CEMS
• Subpart Y Entering Equation Inputs Using IVT
• Subpart Y IVT Equation Inputs Summary
• Using Subpart Y Calculation Spreadsheets