Volatile Organic Compounds (VOCs)

Memo to: Air Quality Staff and Interested Parties

From: Terry L. O'Clair, P.E.—Director, Division of Air Quality

Re: Permitting of Electric-driven Compressor Stations

Date: November 21, 2012

The Department has traditionally issued air quality permits to all natural gas compressor stations operating in the state. These facilities included compressors driven by natural gas-fired engines, which are the primary source of emissions at the site. Based on annual emissions, these sources were usually permitted as minor sources of air emissions.

Over the past several years, the Department has seen an increase in the number of new compressor stations consisting of electric-driven compressors (with other associated equipment including storage tanks, emergency flares, etc.). Facilities with electric-driven compressors tend to have significantly lower emissions compared to stations with engine-driven compressors. Also, there are generally little or no emissions testing requirements at facilities with electric-driven compressors.

Subdivision 33-15-14-02.13.n of the North Dakota Air Pollution Control Rules states that the Department may exempt “Sources or alterations to a source which are of minor significance as determined by the department” from the requirement to obtain an air quality permit for the source. The purpose of this memorandum is to establish guidance to be used to determine when an electric-driven compressor station is considered to be a “source of minor significance” which is not required to obtain an air quality permit.

In general, if the compressors at a compressor station are all electric-driven compressors, an air quality permit (Permit to Construct or Permit to Operate) will not be required for the facility if all of the following conditions are met:

1. A complete application for an air quality permit (with the appropriate filing fee) is submitted to the Department. The application should include a discussion of the applicability of federal regulations as discussed below.


2. Maximum expected VOC emissions from the facility are less than 40 tons/year and maximum expected emissions of any other criteria pollutant are less than 25 tons/year.


3. Maximum expected emissions from the facility of combined hazardous air pollutants are less than 5 tons/year.


4. A glycol dehydration unit will not be operated at the facility.


5. The tanks located at the facility are not subject to 40 CFR 60, Subparts K, Ka or Kb.

Even if an air quality permit is not required, the owner/operator of the facility must still comply with the applicable state and federal air pollution rules and regulations. Federal air pollution regulations that may apply to a facility include, but are not limited to, the following:

1. 40 CFR 60, Subpart OOOO – Standards of Performance for Crude Oil and Natural Gas Production, Transmission and Distribution (NSPS Subpart OOOO).


2. 40 CFR 63, Subpart HH – National Emission Standards for Hazardous Air Pollutants from Oil and Natural Gas Production Facilities. Since a facility which is exempt from the permitting requirement will not be a major source of hazardous air pollutants (HAPs) and will not operate a triethylene glycol dehydrator, this subpart is not expected to apply.


3. 40 CFR 63, Subpart HHH – National Emission Standards for Hazardous Air Pollutants from Oil and Natural Gas Production Facilities. Since a facility which is exempt from the permitting requirement will not be a major source of HAPs, this subpart is not expected to apply.


4. Engines at the facility may be subject to the following:
1. 40 CFR 60, Subpart IIII – Standards of Performance for Stationary Compression Ignition Internal Combustion Engines
2. 40 CFR 60, Subpart JJJJ – Standards of Performance for Stationary Spark Ignition Internal Combustion Engines
3. 40 CFR 63, Subpart ZZZZ – National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines

An air quality permit will not be required based solely on the applicability of federal New Source Performance Standards (from 40 CFR 60) or Maximum Achievable Control Technology standards (from 40 CFR 63).

This memorandum is meant to provide general guidance when determining if an air quality permit is required for electric-driven compressor stations and may not be appropriate where special environmental issues exist. Questions regarding this memorandum may be addressed to Craig Thorstenson at 701-328-5188 or cthorstenson@nd.gov.

Memo to: Storage Vessel Owner/Operators and Interested Parties

From: Terry L. O'Clair, P.E.—Director, Division of Air Quality

Re: Storage Vessels at Oil and Gas Non-Production Facilities

Date: 27 May 2015

Storage vessels located at oil and gas production facilities are currently subject to requirements established by the Department’s Bakken Pool Oil and Gas Production Facilities Air Pollution Control Permitting & Compliance Guidance (Bakken Guidance). Storage vessels located at non-production facilities are not subject to the Bakken Guidance; however, emissions from the storage vessels remain subject to Chapter 33-15-07 of the North Dakota Air Pollution Control Rules. Subsection 33-15-07-02.1 of the rules states as follows:

No person may cause or permit the emission of organic compounds gases and vapors, except from an emergency vapor blowdown system or emergency relief system, unless these gases and vapors are burned by flares, or an equally effective control device as approved by the department. Minor sources, as determined by the department and not subject to New Source Performance Standards (NSPS), may be granted exemptions to this subsection.

Emissions from a storage vessel at a non-production facility are considered to be adequately controlled for purposes of compliance with the above-referenced subsection if emissions are controlled by a flare, floating roof, vapor recovery unit or equally effective control device.

A storage vessel is considered to be uncontrolled if emissions are not controlled by a flare, floating roof, vapor recovery unit or equally effective control device. Uncontrolled storage vessels at a non-production facility are considered to be minor sources which are not subject to the control requirements of the above subsection if both of the following conditions are met:

1. Maximum expected annual emissions from each uncontrolled storage vessel are less than 6 tons/year of volatile organic compounds (VOCs); and


2. Combined maximum expected annual emissions from all uncontrolled storage vessels at the facility are less than 20 tons/year of VOCs.

Storage vessels with maximum expected annual VOC emissions of less than 2 tons/year are not required to control emissions under this policy and are not to be included when calculating emissions from uncontrolled storage vessels at the facility for purposes of this policy.

To be considered adequately controlled for purposes of demonstrating compliance with the requirements of Subsection 33-15-07-02.1 of the rules, storage vessels at a facility must either be controlled in accordance with the requirements of this policy or a site-specific written determination must be obtained from the Department indicating that emissions from each storage vessel are adequately controlled.

All owner/operators required to install control equipment to comply with the requirements of Subsection 33-15-07-02.1 of the North Dakota Air Pollution Control Rules must have the required control equipment installed and operated by January 1, 2016. Failure to install required control equipment will subject the owner/operator of the facility to enforcement action.

Memo to: Storage Vessel Owner/Operators

From: Terry L. O'Clair, P.E.—Director, Division of Air Quality

Re: Current VOC Emissions

Date: October 9, 2017

The North Dakota Department of Environmental Quality (Department) is working to quantify current VOC emissions from condensate tanks and condensate truck load-outs.

Your Company operates several affected sources in North Dakota. Control requirements for volatile organic compound (VOC) emissions are outlined in Chapter 33-15-07 of the North Dakota Air Pollution Control Rules (NDAPCR). More specifically, subsection 33-15-07-02.1 of the NDAPCR requires that organic compound gases and vapors be controlled by a flare or an equally effective control device as approved by the Department. The provisions of this chapter apply to all facilities that emit VOCs.

To assess the current states of these facilities, the Department requires you to take the following actions regarding the level of VOC emissions at each of the facilities that you operate:

1. Calculate the maximum expected VOC emission rate in tons/year from all condensate tanks and truck load-outs. For purposes of these calculations, the maximum expected VOC emission rate is the annual emission rate from the condensate tanks and truck load-outs calculated based on the maximum expected annual throughput for each. The calculations should include VOC emissions from each condensate tank and truck load-out considering the VOC control equipment utilized. The type of VOC control equipment utilized should be indicated on the calculations.


2. Submit the calculations for all facilities to the Department by December 1, 2017. Even if you do not have any condensate tank or truck load-out emissions, please let us know that you do not have any associated emissions. The Department prefers that the updated emissions be submitted electronically to aseligman@nd.gov.

If you have any questions concerning the above, you may contact Angela Seligman of my staff at 701-328-5188 or via email at aseligman@nd.gov for further assistance.

Memo to: Midstream Facilities

From: James L. Semerad.—Director, Division of Air Quality

Re: Compliance Requirements for Condensate Truck Loadout Emissions

Date: February 3, 2020

Volatile organic compounds (VOC) emissions from condensate truck loadouts at midstream facilities are subject to Chapter 33.1-15-07 of the North Dakota Air Pollution Control Rules (Rules). Subsection 33.1-15-07-02.1 of the rules states:

No person may cause or permit the emission of organic compounds gases and vapors, except from an emergency vapor blowdown system or emergency relief system, unless these gases and vapors are burned by flares, or an equally effective control device as approved by the department. Minor sources, as determined by the department and not subject to New Source Performance Standards (NSPS), may be granted exemptions to this subsection.

VOC emissions from condensate truck loadouts are considered adequately controlled for purposes of compliance with the above-referenced Subsection if emissions are controlled by a flare, vapor recovery unit, or equally effective control device approved by the Department. Uncontrolled condensate truck loadouts are considered by the Department to be sources of minor significance and not subject to the control requirements of Subsection 33.1-15-07-02.1 if maximum expected VOC emissions are ≤20 tons per year (tpy).

To be considered adequately controlled for the purposes of demonstrating compliance with the requirements of Subsection 33.1-15-07-02.1 of the rules, condensate truck loadouts at a facility must either be controlled in accordance with the requirements of this policy or a site-specific written determination must be obtained from the Department indicating that emissions from each condensate truck loadout are adequately controlled.

All owners/operators required to install control equipment to comply with the requirements of Subsection 33.1-15-07-02.1 of the Rules must have the required control equipment installed and operating on or before July 31, 2020. Failure to install required control equipment will subject the owner/operator of the facility to enforcement action.

If you have any questions concerning the above, you may contact Angela Seligman of my staff at 701-328-5291 or via email at aseligman@nd.gov for further assistance.

Memo to: Crude Oil Storage and Loadout Facilities

From: James L. Semerad —Director, Division of Air Quality

Re: Crude Oil Truck Loadout VOC Emissions Compliance Requirements

Date: July 13, 2020

Volatile organic compounds (VOC) emissions from all crude oil storage and truck loadout facilities are subiect to Chapter 33.1-15-07 of the North Dakota Air Pollution Control Rules (Rules). Subsection 33.1-l 5-07 -02.1 states:

No person may cause or permit the emission of organic compounds gases and vapors, except from an emergency vapor blowdown system or emergency relief system, unless these gases and vapors are burned by flares, or an equally effective control device as approved by the department. Minor sources, as determined by the department and not subject to New Source Performance Standards (NSPS), may be granted exemptions to this subsection.

The Department considers the operation of crude oil storage and truck loadouts across North Dakota to be normal operations. A temporary or long-term lack of crude oil pipeline transport access is not considered by the Department to be an emergency; therefore, VOC emissions from truck loadout operations must be adequately controlled.

VOC emissions from crude oil truck loadouts are considered adequately controlled for purposes of compliance with the above-referenced Subsection if emissions are controlled by a flare, vapor recovery unit, or equally effective control device approved by the Department. Uncontrolled crude oil truck loadout operations are considered by the Department to be sources of minor significance and not subject to the control requirements of Subsection 33.1-15-07-02.1 if maximum expected VOC emissions are < 20 tons per year (tpy).

To be considered adequately controlled for the pu{poses of demonstrating compliance with the requirements of Subsection 33.1-15-01-02.1 of the Rules, crude oil truck loadout operations at a facility must either be controlled in accordance with the requirements of this policy memorandum or a site-specific written determination must be obtained from the Department indicating that emissions from each crude oil truck loadout are adequately controlled.

Owners/operators of upstream facilities that commence crude oil truck loading, which results in a subsequent increase in VOC emissions due to changes in crude oil pipeline transport access, or for any other reason, must submit an amended facility registration to the Department within 30 days of the change of operations. The amended facility registration must include updated emissions calculations.

In the event that a facility exceeds 100 tpy of a criteria pollutant (VOC, CO, NO*, pM or SOz), 10 tpy of a single hazardous air pollutant (HAP), or 25 tpy of combined total HAps, the owner/operator is required to submit a Title V Permit to Operate application. The Title V permit to Operate application must be submitted within 12 months of exceeding the Title V threshold. It is incumbent on all owners/operators to track facility-wide actual 12-month rolling total emissions and ensure their availability upon Department request.

All owners/operators required to install control equipment to comply with the requirements of Subsection 33.1-15-07-02.1 of the Rules must have the required control equipment installed and operating on or before November 3,2020. Failure to install required control equipment will subject the owner/operator of the facility to enforcement action.

If you have any questions concerning the above, you may contact Craig Thorstenson of my staff at 701-328-5198 or cthorstenson@nd.gov for further assistance.