View PDF version

Informational Letter IL 86-2

5 March 1986

To: All Oil, Gas, and Pipeline Operators

CRITERIA FOR THE EXEMPTION OF SWEET GAS PROCESSING PLANTS FROM APPROVAL REQUIREMENTS UNDER THE CLEAN AIR ACT AND THE CLEAN WATER ACT

This Informational Letter is compatible with the requirements of Informational Letter IL 80-30.

Alberta Environment and the Energy Resources Conservation Board reviewed the application handling procedures for gas processing plants and determined that certain sweet gas processing plants should be exempted from the requirements to apply to Alberta Environment for permits and licences under the Clean Air Act and the Clean Water Act. The Clean Air (General) Amendment Regulation and the Clean Water (General) Amendment Regulation were recently issued formalizing this change.

Appendix I of this Informational Letter provides details of how to determine whether or not a sweet gas processing plant is exempt from sections 3, 4, and 5 of the Clean Air and Clean Water Acts.

All gas processing plants will continue to be subject to section 26 of the Oil and Gas Conservation Act. Section 15.050 of the Oil and Gas Conservation Regulations describes the information requirements for applications for gas processing plants. To facilitate handling of applications by the Board (and Alberta Environment for plants that are not exempt), the following additional information is required regardless of the plant's exemption status:

• maximum rated capacity of equipment which emits NO_x (kW),
• applicable NO_x emission factors (g/kW/hr),
• total NO_x emissions (kg/hr), and
• exhaust stack height(s) and corresponding building height(s).

ISSUED at Calgary, Alberta, on 6 March 1986.

[Original signed by]

W. Solodzuk
Deputy Minister
Alberta Environment

and

G.J. DeSorcy
Vice Chairman
Energy Resources Conservation Board

APPENDIX I

EXEMPTION CRITERIA

1. Clean Air Act

A sweet gas plant is exempt from sections 3, 4, and 5 of the Clean Air Act if its total oxides of nitrogen (NO_x) emissions are equal to or less than l6 kg/hr.

To determine if a sweet gas plant is exempt from licensing under the Clean Air Act, estimate the total NO_x emission (NO + NO₂) using one of the following:

(a) manufacturer's NO_x emission factors;

(b) United States Environmental Protection Agency (U.S. E.P.A.) NO_x emission factors ("Compilation of Air Pollutant Emission Factors, Publication AP-42 (1981)"); or

(c) the following factors:

• gas-fired internal combustion reciprocating engines - 1481 x 10^-9 g/J*
• gas-fired turbines - 126 x 10^-9 g/J
• gas-fired steam generating units, heaters, boilers - 99 x 10^-9 g/J

* where g/J means grams of NO_x per Joule of energy input to the unit.

Maximum rated horsepower for normal operation, corrected for site elevation, shall be used in the determination of total NO_x Such corrections must be documented.

NO_x emissions from flare stacks and pits may be excluded.

Intermittent NO_x emissions from standby equipment and those used for emergency purposes may be omitted from the total NO_x calculation. For the purpose of this exemption, standby equipment does not include equipment idle as a result of over-design or temporary reductions in throughput.

Any subsequent expansion or modification to a sweet gas plant that results in the total NO_x emissions exceeding l6 kg/hr will render the plant subject to the approval requirements of the Clean Air Act.

Note that regardless of exemption status, the requirement that exhaust stack heights be not less than 1.5 times the peak height of the associated building is still in effect.

2. Clean Water Act

A sweet gas plant is exempt from sections 3, 4, and 5 of the Clean Water Act if the following criteria are met:

• no industrial landfill on site,
• no sewage produced, or any sewage which is produced goes to a pit-type toilet, sewage field, leaching cesspool, or municipal plant,
• no discharge of process liquids, waste liquids, or produced water to the surrounding watershed, all above ground tanks for the containment or treatment of process water, wastewater, waste liquids, sewage, or produced water must be diked,
• no on-site pits, ponds, or lagoons for the containment or treatment of liquids, except flare pits or other small pits which comply with the Oil and Gas Conservation Regulations,
• no wastewater irrigation on site, and
• no significant probability of spills or leaks which would contaminate surface runoff water, groundwater, or soil.

These criteria supersede the requirements for licensing and operation of sweet Class A plants as outlined in the Gas Processing Waste Water Management Standards - September 1973 issued by Alberta Environment.