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UST Program - Available Local Guidance (LG) Letters

UST Program - Local Guidance (LG) 127


July 16, 1993

To:  Local Agencies

Several inquiries have been made to our office questioning whether USTs containing oxygenated motor vehicle fuels and gasohols must comply with the requirements for tanks storing motor vehicle fuels or with requirements for tanks storing hazardous substances other than motor vehicle fuels.

Classification of these regulated substances is important when considering compliance with the December 22, 1998 UST upgrade requirements and eligibility for participation in the UST Cleanup Fund.  The need to classify these alternative motor vehicle fuels will become increasingly significant as their production and use increases.

This office requested the United States Environmental Protection Agency (U.S. EPA), Office of Underground Storage Tanks to provide guidance on 40 CFR 280.42 and other relevant portions of the federal regulations pertaining to the storage of oxygenated motor fuels and gasohols.

The U.S. EPA's February 5, 1993 response (see Enclosure 1) states that oxygenated motor vehicle fuels and gasohols containing more than a five percent concentration of Comprehensive Environmental Response Compensation and Liability Act (CERCLA)-listed substances are subject to requirements pertaining to hazardous substances.  Hazardous substances include solvents, waste oils, methanol, new motor oils, among others.  The enclosed table specifies which oxygenated blending agents are currently CERCLA-listed (Enclosure 2).

A motor vehicle fuel is classified as a petroleum product used primarily to fuel engines or self-propelled devices by which any person or property may be propelled, moved, or drawn, Section 2611 of the California UST regulations defines petroleum to include crude oil, or any fraction thereof, which is liquid at standard conditions of temperature and pressure, which means at 60 degrees Fahrenheit and 14.7 pounds per square inch absolute.

Enclosure 3 lists several motor vehicle fuels and several hazardous substances.  Any UST storing a product that meets the description of a CERCLA-listed hazardous substance, but also meets the description of a motor vehicle fuel hazardous substance, must comply with the more stringent UST requirements; that is, the UST may not be regulated under the requirements for motor vehicle fuel tanks.

Sites which are contaminated primarily with a CERCLA-listed hazardous substance or any substance that is not a complex blend of hydrocarbons derived from crude oil are not eligible for participation in the UST Cleanup Fund.

If you have questions regarding the information in this letter, please contact us. Inquiries regarding the UST Cleanup Fund should be directed to Jim Munch at (916) 227-4430.  Inquiries regarding petroleum fuels or other hazardous substances should be directed to Kim Ward at (916) 227-4319.  Questions regarding UST monitoring requirements should be directed to David Holtry at (916) 227-4332.


[Original signed by:]
Mike McDonald, Manager
Underground Storage Tank Program

Enclosure 1

75 Hawthorne Street
San Francisco, CA 94106-3901

Michael McDonald
State Water Resources Control Board
Division of Clean Water Programs
2014 T ST., Suite 130
P.O. Box 944212
Sacramento, CA 94244-2120

Dear Mr. McDonald:

This is in response to the request by your staff for regulatory interpretation of 40 CFR 280.42 and other relevant portions of the Federal Regulations pertaining to the storage of methanol and other alternative fuels.  We have consulted with Headquarters on this interpretation.

Currently, gasohols containing 5% or less methanol do not need to meet hazardous substance UST system regulations, and are treated as petroleum.  Methanol, M85, and other high-level methanol fuels (M90, M80, and M70) are considered hazardous substances.  Oxygenated motor fuels and gasahols (10% ethanol and 90% unleaded gasoline) are considered petroleum and can be stored as such.  Storage of ethanol alone is unregulated under Subtitle I. The attached table clarifies hazardous waste classification for other blended alcohols and ethers.

Existing single-walled methanol UST systems are in compliance if they meet the leak detection requirements of petroleum UST systems as outlined in 40 CFR 280.41, and the stored substance is compatible with the existing system, until Dec. 22, 1998, when they must be upgraded to secondary containment.  The following interpretation pertains to the storage of methanol for new and upgraded systems, and variances.

Owners and operators of new hazardous substance UST systems must currently provide release detection that meets all requirements listed in 40 CFR 280.42 (b). Existing hazardous substance systems must be upgraded to be in compliance with these provisions by Dec. 22, 1998. 40 CFR 280.42 establishes minimum requirements for secondary containment systems, double-walled tank systems, external liners, underground piping, and any other methods of release detection.

 Double-walled tank systems are exclusively those for which an interstitial space exists which would prevent a leak from an inner wall from exiting the outer wall, and where leak detection equipment could warn an operator of an inner wall breach (40 CFR 280.42(b)(2)). Secondary containment systems must be designed, constructed and installed to contain regulated substances released from the tank system until they are detected and removed; prevent the release of regulated substances to the environment at any time during the operational life of the UST system; and be checked for evidence of a release every 30 days (40 CFR 280.42(b)(l)).  Under these definitions, bonded liners and similar methods of treating the inside of a tank wall are not considered equivalent to doublewalled or secondarily contained, and would not meet the Federal requirements.

Variance Procedures

Section 280.42(b)(5) allows for other methods of release detection if owners or operators meet all the requirements of this paragraph.  The Preamble to the final rule (40 CFR 280 and 281, pp. 37156 - 37157) supports this position.  The State may develop a variance procedure for allowing leak detection systems other than those described in 280.43 (b) through (h).  In our view, this kind of variance would be very difficult to obtain. since it relies in part on site specific data, applications for such a variance would need to be site specific.

Please note that the Agency does not at this time intend to develop variance application options that can be used by implementing agencies, as indicated in several paragraphs of the preamble.  If you have any more questions on the storage of methanol, please don't hesitate to call me at (415) 744-2077.

[Original signed by:]
Patricia D. Eklund, Chief
Office of Underground Storage Tanks

Enclosure 2


CERCLA-Listed  Hazardous Substances Non-CERCLA-Listed Hazardous Substances
Common Name Scientific Name Common Name Scientific Name
Methyl alcohol, Wood alcohol methanol Ethyl alcohol, ethanol Wood alcohol  Alcohol, Anhydrous alcohol ethanol
Butyl alcohol, n-butyl alcohol 1-butanol Propyl alcohol 1-propanol
Isobutyl alcohol 2-methyl-1-propanol Isopropanol 2-propanol
    Butanols *
    sec-Butyl alcohol, TBA 2-butanol
    ter-Butyl alcohol 2-methyl-2-propanol
    MTBE methyl-tertiary-butyl ether
    ETBE ethyl-tertiary-butyl ether
    Pentanols *
    Heptanols *
    Octanols *
  * Mixtures of isomers

Enclosure 3
Revised July 28, 1993
Partial List of Regulated Substances
Stored in UST& in California*


unleaded gasoline
diesel to fuel vehicles
diesel for back-up generators
aviation fuel
jet fuel
ethanol products to fuel motor vehicles
any concentration of 2-butanol w/ gasoline (to fuel vehicles only)


Methanol 85 (MS5)
Methanol M70 (M70)
new motor oil
waste oil
diesel for boiler systems
ethanol products used other than to fuel motor vehicles
more than 5% concentration of 1-butanol with gasoline

* This is not a complete list of regulated substances.

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