The purpose of these one to two page summaries is to offer suggestions on how to perform these reviews or key points to remember when conducting these activities. They are also intended as a starting point or a template for ESC customers to develop their in-house and site specific procedures, check lists, or other helpful tools for people to use.

These summaries are not “all encompassing” and do not contain every relevant piece of information on these topics. Where possible, I have included any regulatory reference that might be available so that you can double check theses references. In addition, I am including suggestions and recommendations based upon lessons I have learned over the years I’ve been involved with CEM systems.
As always, operators of CEM systems should consult their air permits and any guidance that your state or local agencies might have available. Please check the appropriate websites for more information.

The key document you should understand more than any other is the plant’s Title V Operating permit. This should tell you:
• What fuels are acceptable to burn
• What operating conditions are acceptable and which are not
• What are your emission limits, and what is the compliance demonstration methods?
• What work practice standards you must follow
• What periodic performance testing is required?
• What, if any, CEMS systems are to be installed, certified and operated
• What records must be kept and for how long
• What reports and records must be submitted to the affected agencies (local, state and federal), what information they must contain and how often they are to be submitted
• And so much more…

Different types of facilities fall under different subparts of the Part 60 regulations. When your facility was built and which types of controls were considered to be BACT (Best Available Control Technology) at that time, determined which pollutants were regulated and what emission limits a facility had to show compliance with.

Methods of demonstrating compliance changed over the years as new technologies for monitoring were either developed or existing methods were improved. Three types of compliance demonstration methods which are still used today are:
1. Work practice standards
2. Periodic stack performance testing
3. Continuous emission monitoring systems (CEMS)


Captured in your permit are the specific regulations that your facility falls under. Some of those regulations are:
• Actual Part 60 regulations, that are relevant to your facility, such as (partial list):
o Subpart A, General Provisions, §§60.1 – 60.19
o Subpart D, §§60.40 – 60.49
o Subpart Da, §§60.40Da – 60.52Da
o Subpart GG, §§60.1 – 60.19
o Subpart KKKK, §§60.1 – 60.19

Be aware that many facilities operate CEM systems that record emission readings to show or demonstrate compliance for several different reporting programs simultaneously. The most common examples are SO2, NOx, CO2/O2 monitors for both Part 60 and 75. Frequently, Data Acquisition and Handling Systems (DAHS) have duplicate parameters within their CEM configuration. One set for P60 reporting (example NOx60) and the other for P75 reporting. Operators of diluent (CO2 or O2) monitors need to be aware that the data generated by these systems are frequently used in the derived calculations for NOx lb./mmBtu, SO2 lb./mmBtu, CO lb./MMBtu, NOx ppm@15%O2 or NOx ppm@7%O2.

Be aware that the P60 air monitoring regulations are generally considered to be the first set of air regulations to be published by USEPA. When compared against the newer P75 regulations, the P60 regulations are not as complete and are silent on many of the quality assurance and data validation issues. This silence can lead to inconsistency in the interpretation from agency to agency, so therefore, it is strongly recommended you review and understand the expectations of your local air control agency.

When the P75 regulations were being written in the 1990’s, the authors of the P75 regulations recognized the weaknesses and vague areas found in P60 and tried addressing these areas, thereby making P75 more complete, more definitive and a better all-around set of regulations. Despite all of these efforts, P75 regulations are still not perfect. 

In addition, each state administers the P60 regulations in their state, with oversight from the USEPA. This can lead to inconsistencies between state to state for how a regulation is interpreted or what the state’s expectations are. For this reason, it is very important that you work closely with your state compliance people so you understand what their expectations are.

Some states have announced that they will accept the more restrictive QA requirements of Part 75 to replace the looser Part 60 QA requirements. This might also impact how data is validated (forward or proactively like P75 instead of historically, as is the case for P60). Again, be sure your management understands what your local agency (state or county) is willing to accept.

Download the pdf document here.

Jon Konings, Senior Regulatory and Reporting Engineer, ESC    Published: 10/5/2016 5:10:39 PM

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