Mendocino County

Air Quality Management District
Wildfire Smoke Protection  Air Advisory

Gasoline Dispensing Facility

GDF Information

A gasoline dispensing facility (GDF) is a private or public facility where gasoline is dispensed into vehicle fuel tanks. Gasoline vapors are released from a GDF when gasoline storage tanks are filled and when gasoline is dispensed into vehicle fuel tanks. Because gasoline vapors contribute to ozone pollution.

The District requires owners of GDFs to have equipment to capture these vapors to prevent them from being released to the atmosphere. State and Local air agencies inspect and test the vapor control equipment at GDFs to help keep the air clean.

The two main types of vapor control equipment at GDFs are known as Phase I and Phase II vapor controls.

Phase I emission controls

Phase I emission controls reduce the amount of gasoline vapors released when storage tanks are filled. This equipment uses a combination of pipes and hoses to collect displaced gasoline vapors from the tank and route them back into the delivery truck.

A submerged fill pipe, or "drop tube," consisting of a tube installed to within 6 inches of the bottom of the tank, significantly reduces splashing and vapor generation as the tank is filled.

Phase II emission controls

Phase II emission controls reduce gasoline vapors when gasoline is dispensed into vehicle fuel tanks. This equipment captures displaced vapors at the vehicle fill neck and routes them back to the underground storage tank.

What is an Aboveground Gasoline Storage Tank or AST?

Answer: An AST is a gasoline storage tank that is intended for fixed installations, without backfill, that is located above or below grade. ASTs are commonly classified as either "single-wall" or "protected". Single-wall ASTs are constructed with a primary (single) wall typically made of steel. Protected ASTs are constructed with a primary (inner) tank encased by a secondary (outer) tank, with a layer of insulating material (at least three inches thick) between the primary and secondary walls. The insulating material is usually lightweight concrete or a similar material.

Are gasoline dispensing facilities equipped with ASTs located in "attainment areas" for the Federal standard for ozone exempted from SLC requirements?

Answer: Yes, existing ASTs in Federal ozone attainment areas are not required to comply with SLC (Standing Loss Control), but these ASTs must keep their pre-EVR Phase I and Phase II equipment. Any new AST installed after April 1, 2009, regardless of whether it is in an attainment area or not, must comply with SLC requirements.

Who is subject to Phase II EVR?

Answer: No new or existing ASTs are subject to Phase II EVR as of April 1, 2014. Phase II EVR requirements will apply once a Phase II system is certified for ASTs. Existing ASTs subject to Phase II EVR will have four years from the effective date to comply. The effective date is the date when the first Phase II EVR system for ASTs is certified. A Phase II EVR system is expected to be certified sometime in 2014.

Executive Orders for GDF

Vapor recovery Executive Orders for Above and Underground Storage Tanks can be found Here..

Where can I get more help?

Contact MCAQMD for questions and notifications concerning the testing of vapor recovery equipment, permitting issues, CARB requirements, or other issues. Call our District phone line at 1-707-463-4354.

ARB has more information on GDF (Gas Dispensing Facilities)Here.

Please contact the District with any questions.

Burn Day Status

For todays burn day status please call 707-463-4391. .

Burn Permit Application> Click Here
SMP Online Burn Request> Click Here

Credit Card Payments

Service FEES are assessed to all Credit Card transactions by govPayNet:

Air Quality for Mendocino

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News / Advisories

Mendocino County: Fire Season - Burning is allowed only on permissive burn days with a valid burn permit.

Air Quality Advisory For Mendocino County covering smoke impacts from wildfires in Northern California (month of August 2020). Click Here for More Information

COVID-19 AIR DISTRICT OPERATIONS - The public counter will be closed to walk-in customers. Click Here for More Information

AB 617 Community Air Protection Incentive Projects - AB 617 Community Air Protection Incentives to Reduce Emissions. Click Here for More Information

Volkswagen Environmental Mitigation Trust - provides about $423 million for California to mitigate the excess nitrogen oxide emissions caused by VW's use of illegal emissions testing defeat devices in certain VW diesel vehicles.. Click Here for More Information

Air District Relaxes Portable Diesel Engine Enforcement - ARB has determined the standards for DPM may not be feasible. Click Here for More Information

The District Mission

  The mission of the Mendocino County Air Quality Management District is to protect and manage air quality, an essential public resource upon which the health of the community depends. 

  Mendocino County Air Quality Management District is one of 35 local Air Districts in California.

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