When Roy LaCross retired 17 years ago, he began his "stamp project" as a way of both keeping him in touch with people and raising some money for charity.

It's turned out to do that, and more.

LaCross, who is 79, collects used envelopes from businesses, institutions and individuals and recycles the canceled stamps to dealers who in turn sell them to collectors around the world. He uses the funds from the venture to send inner-city youth off on church-sponsored camping trips.

In the process, he has mobilized several residents of the Springvale Terrace retirement home in Silver Spring to help him soak off the stamps, dry them and sort them for packaging.

"It's therapy for them," said LaCross. "People like to be doing something for others."

LaCross observes that "it takes a great volume" of used envelopes to yield enough stamps to make the project worthwhile. But with "no cost for the material, no overhead and volunteer labor," the venture pays off.

He gives the proceeds to Teen Haven, a nondenominational organization that maintains a year-round camp in rural Pennsylvania, to give inner city young people a weekend or week-long fresh experience in wholesome surroundings.

The group began 17 years ago, "sending just a couple of kids a year," he said. "Now we're up to 50 or 60 a year."

What LaCross had not expected was the volume of unexpected treasure that has turned up in the trash he collects.

"I've turned back thousands of thousands of dollars worth of checks," he said -- checks that were missed by those who opened the mail.

"Never a week goes by that we don't find a check in somebody's mail," said LaCross, who for 30 years was a civilian personnel officer for the Army Medical Department.

He has found checks ranging from $6,500 to just a few dollars. Most are in the used envelopes he picks up from banks. "Everybody makes mistakes, even in banks," he said.

He recalled one bank where he'd picked up used envelopes for years, when management decided the envelopes should be cut in half before being tossed in the trash. "I tried to persuade them not to," he said, telling bank officials that if an enclosed check is missed he would retrieve it and "just you and I would know a mistake was made."

The assistant cashier assured him the bank never made mistakes, he said.

"The very first time they cut them," LaCross found the remains of "over $3,000 worth of various dividend checks that a lady was trying to deposit. Can you imagine the trouble it took to go back to those companies and get their computers programmed to reissue those checks!"

LaCross, an active lay member of Westmoreland Congregational Church who over the years has "been on all the boards," submits an annual report of his stamp project as part of the church's benevolences.

This year, he noted, the volume has been decreased somewhat because one of the businesses he used to pick up envelopes from decided to recycle its trash. "That particular outfit probably made more mistakes" by missing enclosures "than any other," he said.

Many of his contacts for acquiring the envelopes come through Westmoreland Church members and their business or social contacts, as well as other United Church of Christ congregations, he said.

The involvement of Springvale Terrace residents was a natural, because LaCross has been on the board of directors of the United Church of Christ-sponsored home and its predecessor institution since 1958.

LaCross cheerfully admits that his stamp project has evolved into a full-time job and that "I work longer now for nothing than I ever worked for pay . . . . "When I was in personnel work, I always told people to plan for their retirement. Somehow I overplanned mine!"