Gasoline is considered a necessity of life, but is one more gas station a necessity for the Vineyard? The Martha's Vineyard Commission was expected to take up the question again last night as a public hearing reopened on a proposal for a new gas station on State Road in Vineyard Haven.

Tisbury Fuel Services wants to build a two-pump filling station on High Point Lane, off State Road in Vineyard Haven behind the old Coca-Cola plant.

The project is under review by the commission as a development of regional impact (DRI). It is the second gas station project to be reviewed by the commission this year; in September the commission voted unanimously to reject a plan for a three-pump gas station, also at the site of the old Coke plant off State Road. At the time members of the commission questioned the need for another gas station on the Island, they also raised concerns about the impact of a State Road gas station on the smaller mom-and-pop stations up-Island.

The commission appeared to be poised to reject the Tisbury Fuel Services project for the same reasons, but project developer Sean Conley requested a delay while he prepared a report on the economic impacts of a new gas station on other Island stations.

Prepared by Mr. Conley and released this week, the report includes an extensive compilation of population statistics and data on the numbers of registered cars on the Vineyard. It also includes an analysis of the impact from a new gas station on other stations. But an independent consultant hired by the commission to review the report said Mr. Conley's numbers are only assumptions and impossible to verify.

"While I think the applicant was reasonable in the way they put the analysis and the presentation together, there is no way to fully verify their numbers," wrote Richard K. Gsottschneider, a partner at RKG Associates, a New Hampshire consulting firm. Mr. Gsottschneider was hired by the commission at the expense of the applicant to review the report.

Tisbury Fuel Services is promising a discount of 20 cents a gallon for year-round Island residents (the plan calls for using a special resident card based on the Steamship Authority Islander profile card), and the project developers are also promising to contribute a penny to the Dukes County Housing Authority from every gallon of gas sold. The developers say they expect to pump 1.4 million gallons of gas every year.

"If we save someone 20 cents gallon . . . you are probably saving a family in Vineyard Haven $300 to $500 a year," Mr. Conley said.

Mr. Gsottschneider conceded that the applicant's proposal to offer lower gas prices and create more competition in the local gas market is a sound concept, but he also concluded bluntly that a new gas station on State Road could put another gas station on the Vineyard out of business.

"If they do more volume than they projected, they could in fact put one of the existing gas stations out of business, thereby not really adding much to the competitive situation they argue is so important," the consultant wrote.

In the report Mr. Conley documents the lower number of stations on the Island today (nine) compared with 1970 (15), and uses growth rate projections to bolster his position that a new service station will be needed in the years ahead.

But Mr. Gsottschneider said the declining number of stations is actually a national trend against a backdrop of more fuel-efficient vehicles and fewer stations with higher sales volumes. He also said Mr. Conley's growth rate projections may be overly optimistic.

"There is of course no guarantee that future growth rates will match those of the past 10 years, which was a time of unprecedented prosperity. In fact I believe the growth rates they used for forecasting purposes are overly aggressive and it may well take more than five years before the market increases sufficiently to justify a new station," Mr. Gsottschneider wrote.

The Conley report estimates that about 11.5 millions of gasoline were sold on the Island last year, and it projects that by the year 2007 the demand will rise to 13.7 million gallons. The report also estimates that a new station at Tisbury Fuel Services will divert 3 to 35 per cent of the business from other gas stations, depending on their location. The report estimates that a new service station on State Road in Vineyard Haven will take away about 10 per cent of the business from Up-Island Texaco, but here again, Mr. Gsottschneider said because the numbers are all based on assumptions, there is no way to know if they are accurate.

Mr. Conley, in turn, took issue with Mr. Gsottschneider's critique.

"The basis of our report was that there were more stations 32 years ago than there are today and we've had tremendous growth - there are a lot more cars and a lot more people. And that's going to continue," said Mr. Conley, who is a real estate broker in West Tisbury.

"This has been a very frustrating process because no evidence was brought in from other gas stations - they didn't show any documents about profits or numbers of gallons pumped," he added.

Gas station owners did object to the Tisbury Fuel Services project - especially the owners of the smaller stations up-Island, who claimed a new cut-rate station on State Road could put them out of business.

The report is accompanied by a number of pages of background material about gas station business and competition, but much of the material is dated and anchored in a study done in Los Angeles in 1951.

Among other things, the study found that the factors influencing gasoline consumers include the personality of the attendant and the cleanliness of the restrooms. "Unlike some products (e.g. candy), gasoline as such is not a product for which the consumer has a desire. . . . Unlike the sale of certain types of products (e.g. automatic home laundries), the sale of gasoline does not have the effect of removing the buyer from the market. . . . Unlike certain products (e.g. women's stockings), gasoline is used up in initial consumption," the 1951 report concludes.

MVC executive director Mark London said this week that the central questions for the commission will center on traffic impacts and need. "The traffic impact does seem to be a negative, but the bigger question here is if the traffic is a negative, it begs the fundamental question: Do we really need this? These are the factors that the commission will consider as it weights the benefits and detriments," he said.