They've been living on the edge all summer, and now it seems the Washington Capitals could stay there indefinitely.

National Hockey League rules have no established preseason deadline for a team to declare itself in trouble or inoperative. Although member clubs must pay league dues by Aug. 1, such payment does not guarantee that a team will play through the season.

"One thing really doesn't have anything to do with the other," said NHL legal counsel Gil Stein. "Teams pay dues in advance of the season, but that doesn't mean they will finish it. Cleveland (now merged with Minnesota) and Colorado (now the New Jersey Devils) both said they couldn't finish out their season midway through the year."

To date, team owner Abe Pollin has not advised the league that the Capitals will not operate in the 1982-83 season. Should the team's financial woes force it out of business, the new NHL schedule will need an extensive and speedy overhaul.

No contingency schedule has been drawn up in the event Washington does not participate next season. According to Brian O'Neill, NHL executive vice president, "We're right at the tail end of (preparing) our schedule, and if anything was to happen, we'd have to start all over again."

The schedule tentatively is due out Aug. 1. Originally it was set for release last spring, but when the Rockies moved to the Meadowlands, that schedule was scrapped.

O'Neill said no deadline has been set for resolving the Capitals' situation, but added, "We can't let it go too long. Sooner or later you have to let people know where they're going to play and when."

A first draft of the schedule has been issued to all clubs, who can suggest changes to the league office. The schedule is "based on Washington in Washington," according to one league spokesman.

O'Neill declined to speculate on how long the Capitals can remain an unsolved problem, saying, "I wouldn't like to name a date. If I start doing that, then it looks as if we're setting deadlines."

John Ziegler, league president, was not available for comment. At last month's board of governors meeting, discussion of the Capitals was recessed, and a meeting on the subject can be called with 48 hours notice.

At the time, Ziegler said as long as the league had not been told Washington would be inoperative next season, there was no "Washington situation."

He also confirmed that Pollin was seeking investors, and would consider operation of the club in another city, although no potential moving sites have been discussed officially.

Since that meeting more than three weeks ago, several would-be buyers have been reported interested in the club, although no formal offers have been made. Pollin is asking $7.5 million for the Capitals.

Art Kaminsky, the New York agent-attorney who represents one group interested in the Capitals, said yesterday, "Nothing has changed at this point. We're supposed to have a meeting today, and we may know something later in the week."

Pollin did not return phone calls yesterday.

Pollin did call a member of the Save the Caps Committee to express appreciation for the recent surge of fan support. That group is taking pledges for season tickets in hopes of selling out Capital Centre next season.

No ticket prices have been set for the coming season, but at least 40-50 new requests for season tickets have been received by the Capitals. Current season ticket holders have not yet been issued renewal forms.