Dave Parro will become the 56th goaltender to perform in the National Hockey League this season when he starts for the Washington Capitals Wednesday night against the Edmonton Oilers. If Parro falters, No. 57 will make an appearance, too.

Parro, called up from Hershey Monday, flew here today with the Captials. Rollie Boutin, Hershey's other goalie, is scheduled to fly in Wednesday, after being grounded today when snow closed the Harrisburg Airport. Although Boutin played in 18 games for Washington last season, he has not seen NHL action this year.

Just in case Boutin runs into more travel problems, the Captials also summoned Neal-Girard from the Regina Pats of the Western Hockey League for duty Wednesday. Giard, who was sharp in the Capital's training camp, was sent back for a final year of junior play because Washington had nowhere else to send him.

Gary Inness, the forgotten man of the Capitals, will report to Hershey Wednesday, along with Bart Hunter, who was called up from Port Huron of the International League.

The game of musical goalies was accelerated because Wayne Stephenson, the varsity's No. 2 man, was unable to practice today. He is still troubled by a bone bruise on the kneecap suffered in a pregame warmup Dec. 17. Stephenson was virtually helpless Sunday when he was forced to replace starter Mike Palmateer, victim of a hamstring pull. Palmateer started the Captial's last nine games, but he will be unavailable for at least a week and probably longer.

Wednesday's game offers an excellent opportunity for Parro, 23, a native of Saskatoon, Saskatchewan, to win an NHL job. A second-round 1977 draft choice of the Boston Bruins, Parro was lost to Quebec in the merger draft and then dealt to Washington for forward Nelson Burton. Although outstanding in a 1979 exhibition against the New York Rangers, Parro has been the victim of a numbers game while a Washington farmhand.

Barring a sensational performance by Parro, Boutin will probably be given the starting assignment Thursday in Calgary. Boutin, also 23, comes from nearby Westlock, Alberta. He posted a 3.50 goals-against mark a year ago, best ever by a Washington goalie, but was given no chance to beat out Palmateer and Stephenson this season.

Inness was brilliant two years ago, as he was picked up from the defunct Indianapolic club of the World Hockey Association and posted a 14-14-8 record for a Washington team that had been playing horribly before his appearance.

An attempted power play by Inness' agent, a demand for contract renegotiation that Inness claims he knew nothing about, put Inness in the Capitals' doghouse and, according to General Manager Max McNab, forced Washington to make the deal with Philadelphia for Stephenson.

Inness played sparingly with Washington last season, then he and Parro led Hershey to the Calder Cup, with Inness posting a remarkable 2.82 goals-against average in eight playoff games.

This season, Inness' option year, he was consigned to limbo, and a broken hand during training camp made his situation even worse. However, Inness convinced McNab he had nothing to do with the contract situation two years ago and for the last two months McNab had tried to place him with minor-league teams, failing in both Birmingham and Houston. Now the injury situation has given him one more chance.