Smaller Sources and Potential to Emit

With major source limits in the Denver metro area non-attainment area lowering to 25 tons per year of NOx or VOC in early 2022, many sources that have previously considered themselves to be small may be bumping into major source limits and the permitting requirements applicable to major sources.  The 25 tons per year emission level is based on a facility’s Potential to Emit (PTE).  A PTE inventory shows the maximum amount of emissions that COULD come from your facility if it were running at maximum capacity all the time, even if your facility would never run consistently at that level.

Does your facility have a Potential to Emit (PTE) Inventory?  If you have some sources that are controlled, you may or may not be able to count that control in your PTE Inventory, depending on your permits.  Maybe your facility only has a few sources that require a permit and the emissions from those sources added together are less than 25 tpy of NOx or VOC, but did you include your insignificant sources, such as gas-fired heaters, fire pumps, emergency generators, and small fuel tanks, in your PTE?  If you would like to discuss your facility’s PTE inventory, Applewood can help!

Planning for Ozone Non-attainment Downgrade – Again

On December 15, 2020 Governor Polis released a statement about his intentions to push for a downgrade for the Denver Metropolitan/North Front Range Area from serious to severe non-attainment for the area’s ozone levels.  The area has been unable to achieve a ground-level ozone standard of 75 ppb.  The statement said that state agencies and stakeholders should plan for the downgrade in 2022.

Currently, sources that have a potential to emit (PTE) over 50 tons per year of VOC and NOx need to have Title V permits.  However, this will likely soon change again.  The major source level was only recently moved down from 100 tons per year in January of 2020.  Sources that have air permits with VOC or NOx emissions between 25 and 50 tons per year are going to have to either limit their emissions to less than 25 tons per year or apply for a Title V permit within 1 year of the severe designation.

If a source intends to submit a synthetic minor permit, which would limit their emissions to less than 25 tons per year, then the permit needs to be ISSUED by the Air Pollution Control Division within the 12-month period after the change to avoid Title V permit application requirements.  Often permits take several (4-18) months to be issued by the Air Pollution Control Division, so applications for synthetic minor permits need to be submitted in the upcoming months.

If a source intends to submit a Title V permit application, the application will need to be submitted within 12 months of the redesignation date, so likely in 2023.

Sources should now be looking at their PTE accounting and deciding what will work best for them.

To help sources decide which direction to go with their air permit, Applewood has assembled the following table that outlines the benefits and disadvantages of each type of air permit:  Benefits and Drawbacks of Major or Minor Source Permits

Project Emissions Accounting Update

On October 22, 2020 the EPA finalized the latest guidance on Project Emissions Accounting for Prevention of Significant Deterioration (PSD) and Nonattainment New Source Review (NNSR). In short, the new guidance says that sources can consider emissions reductions in the first step of emissions accounting, which allows them to couple emissions reductions with increases that may be necessary for their process. These reductions can help sources avoid a more complicated permitting process.

It is, however, up to some individual states to decide if they want to follow this guidance. States can decide to use the old guidelines which do not allow for subtraction of emissions reductions in the first step of the process.

For more details on this final action on Project Emissions Accounting, the EPA has a fact sheet and a link to the final rule posted here:


New Source Review Permitting “Adjacent” Guidance

Should two adjacent sources be combined for air permitting purposes? On the surface this may seem like a simple question. However, guidance from the EPA on this topic has switched over the years. Originally, in 1980, the EPA focused on combining sources that were adjacent in terms of physical proximity as well as industrial grouping and common control. Over the years the policy has been interpreted differently by using case-specific facts related to shared equipment, shared workforce, ownership and contracts.

On November 26, 2019 the EPA issued a new memorandum providing guidance on this issue. This memo focuses on using a common dictionary definition of contiguous which means that two pieces of land should be in physical contact with one another. The new memo can be found here:

It is important to note that each scenario is different and often an attorney should review the facts specific to each case. This most recent memo from the EPA provides guidance for permitting authorities. They are encouraged to, but do not have to follow this guidance.