William Lynn Costello, a founding member of the Ashburn Volunteer Fire Department and its chief for nearly two decades, died last Thursdayof congestive heart failure. He was 94.

Costello was born on a farm near Dranesville in Fairfax County on March 27, 1910. He moved to Ashburn in 1937 when it was still a village of just a few hundred people, mostly farmers. After several children died in a house fire, community leaders organized a fire and rescue service in 1944. Costello was a charter member and served as chief of the squad, known as Company 6, for about 20 years, from the 1940s to the 1960s.

Costello was often known as "Billy," but some also called him "Chief," even when he was no longer serving in that capacity.

"You had a guy that everyone was happy with for 20 years, which is unheard of," said Daniel Corder, a captain in the Loudoun County Department of Fire and Rescue.

Corder met Costello in 1974 when he joined the Ashburn volunteer squad at age 15. He said the experience helped inspire him to pursue firefighting as a career.

"His gift was being able to teach you how to treat people," Corder said, recalling how Costello's calm demeanor helped defuse tense situations among people as well as put out fires. "You never heard him say a cuss word."

While Costello volunteered for the fire department, often spending most of the night fighting a blaze, he would rise early the next morning to make his living hauling milk from Loudoun to Washington almost every day. That was how he met Steuart Weller, an Ashburn farmer, in the late 1950s. Weller took down his fence after a blizzard so that Costello could drive across the snow-covered fields to pick up milk from a neighboring dairy farmer.

The harshest word Costello was likely to utter after such an ordeal would be "shucks," Weller said.

"Mr. Costello was one in a billion," said Weller, who fought fires alongside Costello when he joined the volunteer company in 1968. "He never ever had an angry word with anyone. He could work with anyone and share all his knowledge with you."

It was not uncommon for Ashburn residents to call the Costello home to report a fire. A siren at the grocery store across the street from the home would summon the firefighters. Costello's son Larry recalled that in the late 1950s, a button was installed in the house to activate the siren from there.

Costello received formal firefighter training in Williamsburg, after which he recognized the need for training programs in Loudoun. In 1953, he helped set up courses in Loudoun on such subjects as fire safety and how to use equipment.

Costello continued to respond to fires until 1981. He moved to Leesburg in 1986 and to Raleigh, N.C., where he died, two months ago.

Costello's wife of 62 years, Frances, died in 2001. He is survived by his sons, Larry Costello of Raleigh and Rod Costello of Marietta, Ga.; three grandchildren; and three great-grandchildren.

A viewing will be held from 7 to 9 p.m. tomorrow and a funeral at 10 a.m. Saturday, both at Colonial Funeral Home, 201 Edwards Ferry Rd NE, Leesburg. The funeral will feature full firefighter honors: Costello's casket will be hoisted onto a firetruck and be taken in procession with other emergency vehicles to Union Cemetery in Leesburg.