At Fairfax County's more than 3,000 vending machines, a thirsty person can buy all the iced tea or fruit punch he can drink from a pop-top can. What he can't do is buy a carbonated soft drink from a pop-top can.

To Jay Davis, a 7-Up Bottling Co., spokesman, that discrepancy "is just another example of how silly Fairfax County's ordinance dimitting the safe of throwaway carbonated drink containers; really is."

But some Fairfax supervisors complained yesterday that the continuued sale of pop-top cans, albeit filled with iced tea or fruit punch, shows how drink distributors have circumvented their three-month-old law.

"Allowing noncarbonated drinks so be sold in exactly the same kind of cans we had for 7-Up flies in the face of the intent of the county's legislation," Davis said.

While some supervisors said they agree with the sentiment expressed by DAvis and other bottling officials, they generally don't agree that the ordinance should be repealed, as bottlers would like,

Instead, the county attorney's office is now studying how to amend the law to ban the sale of all soft drinks in pop-top cans, including the ones now being sold in the county's administrative offices in Fairfax City.

The ordinance, which went into effect Sept. 1, prohibits sale of nonalcoholic carbonated beverages in nonreturnable containers unless shopkeepers agree to refund at least a nickel to each consumer who returns an empty container. It does not cover beer and liquor, or noncarbonated soft drinks like Tru Ade [WORD ILLEGIBLE] tea, fruit punch, chocolate drinks and spring water. The law is aimed at reducing roadside and park litter.

"This was an ordinance against throwaway containers. It wasn't intended to discriminate against carbonated beverages," said board member Martina V. Pennino D-Centreville who supported the ordinance. "But the fact that vending machines are continuing to dispense any other kind of drink in pop-top cans boggles one's mind."

Fairfax County Executive Leonard L Whorton said county police are investigating "whether the ordinance is achieving the results intended," or whether sales of canned beverages in vending machines are defeating the intent of the ordinance."

Assistant County Attorney W McCauley Arnold said the wording of the ordinance is intended to exempt products that usually are not a source of roadside litter, such as canned soups, baby food, pickles and fruit juices.

While Fairfax officials study the law, representatives from bottling companies are attending civic association meetings in the county to "discuss" the ordinance.

"We go to answer peoples' questions about this ordinance," said W Edward Gregory, public relations director of the Pepsi Cola Bottling CO, and spokesman for the area's soft drink industry.

Pennino said the industry's attendance at civic meetings is "an attempt to get civic pressure against us (the board) to change the ordinance."

Gregory and C M Byrd, manager of the Coca-Cola Bottling CO. plant in Alexandria, said their companies' grocery store sales of soft drinks in Fairfax are down 30 per cent from last year. They blamed the loss on the ordinance.

"Of course all our vending business is down about 90 per cent," said Gregory. All three bottlers said their companies' soft drink sales had gone up markedly in localities bordering Fairfax County.

When the Fairfax ordinance was being debated, opponents said it would lead to a higher cost for consumers.

A check yesterday at a Giant food store in Vienna showed that soft drinks in returnable bottles were still selling at the rate of 40 to 50 cents per quart cheaper than the 52-to-56-cent price per quart on the old throwaways. However, at a nearby 7-Eleven store, the price of a 16-ounce coke or Tab was 35 cents (after the five-cent fefund), the same as the price for the old throwaways.

"We're not getting returnable bottles back in Fairfax County, though," said Byrd. "I don't know what these people are doing with them but they're not turning them in.We're running a 60 to 80 per cent loss on the bottles."