September 30, 2004

Mr. Thomas Driscoll, Senior Environmental Scientist

USEPA/OAQPS/EMAD/EFPAG

109 TW Alexander Drive (D243-02)

Research Triangle Park, NC 27709

Re: Texas Commission on Environmental Quality's (TCEQ) Comments Regarding the Stage II Vapor Recovery Systems Issues Paper dated August 12, 2004

Dear Mr. Driscoll:

The Texas Commission on Environmental Quality (TCEQ) applauds the Environmental Protection Agency's (EPA) efforts to identify gasoline vapor recovery issues faced by Texas and other states. Numerous issues are affecting vapor recovery programs at the state level, including the creation of the California Air Resources Board's (CARB) Enhanced Vapor Recovery (EVR) program, the increasing number of on-board refueling vapor recovery (ORVR) equipped vehicles, and the ongoing development of new control technologies. The TCEQ submits the following comments on Stage II vapor recovery systems (VRS) required at gasoline dispensing facilities (GDF) regarding potential definitions for "widespread use" and other associated issues.

In the past, Texas and other states have relied upon CARB to test and certify new Stage II systems and equipment. Since the implementation of their EVR program, CARB no longer certifies or provides support for the previous VRS efficiency standard of 95%. In November 2002, the TCEQ promulgated requirements for ORVR compatibility of Stage II systems and developed a third-party certification program to allow for the development of new equipment to be used with pre-EVR systems, and for new systems meeting pre-EVR standards. In essence, Texas has attempted to continue the pre-EVR standards while incorporating a requirement for ORVR compatibility.

A major issue affecting the Stage II program is the extremely high percentage of vacuum-assist vapor recovery systems present in Texas. For example, the Houston-Galveston nonattainment area has approximately 92% compared to a national average of 47%. As noted in the August 12, 2004 issues paper, most current vacuum-assist systems have varying degrees of incompatibility with ORVR systems, some of which result in excessive fugitive and vent emissions from GDFs. The TCEQ has promulgated requirements for ORVR compatibility, however, the method of determining widespread use of ORVR will have a significant impact on the Texas program. It is possible that widespread use, depending on the definition chosen by the EPA, could occur relatively soon after the TCEQ's ORVR compatibility deadline for existing Stage II systems which is April 1, 2007.

Mr. Thomas Driscoll, Senior Environmental Scientist

Page 2

September 30, 2004

The following is a summary of TCEQ's concerns:

•	Phase-out of Stage II systems once widespread use is determined. Because faulty vacuum-assist systems have the capacity to cause more fugitive and vent emissions than a GDF without Stage II, simply ceasing to investigate GDFs with Stage II would harm air quality as numerous vacuum-assist systems would remain in service without maintenance or oversight.

•	Actual in-use efficiency (IUE) for ORVR systems. The EPA issues paper notes that ORVR IUE is expected to be 95 to 98%. The issues paper does not analyze or cite any studies undertaken to determine the actual IUE for ORVR systems. The TCEQ has requested information from automobile manufacturers regarding ORVR IUE, but has not received any data. The TCEQ requests that EPA provide the states with technical documentation demonstrating the stated ORVR IUE of 98% as well as information detailing how EPA plans to ensure that automobiles continue to comply with this standard. Texas believes that EPA should analyze IUE and provide results of their analysis to the states.

•	EPA should consider mandating ORVR compatibility for states that choose to continue their Stage II programs in order to achieve more SIP credits.

•	The August 12, 2004 issues paper notes that the Houston-Galveston area of Texas has a vacuum-
assist system percentage of 64%. The actual percentage is approximately 92% (based on data obtained for 2,472 facilities).

•	If the widespread use definition (c) is adopted, the EPA should provide guidelines on how states can use readily available data to accurately determine in-use efficiency for existing Stage II systems.

•	EPA should provide timely guidance on exemptions for facilities dispensing 100% of fuel to ORVR-
equipped vehicles (rental car facilities and car dealerships).

•	From a modeling standpoint, definition (b) would be the easiest and most realistic way to determine widespread use.

•	Any widespread use definition requiring data on percentage of gasoline dispensed would require additional reporting, because Texas has no regulation requiring individual facilities to report gasoline throughput data.

•	The TCEQ agrees with the EPA regarding the need for new emission factors. Currently, only Stage I and Stage II factors allow for local input (others are generic). It may be more beneficial to also allow local inputs for such things as liquid temperature and Reid vapor pressure.

The TCEQ appreciates the opportunity to comment on the proposed definition of "widespread use" and other Stage II issues. If there are any questions or a need for clarification on any of the comments submitted, please contact me at 512/239-3900.

Sincerely,

David C. Schanbacher, P.E.

Chief Engineer

Texas Commission on Environmental Quality