Dozens of firefighters battled demanding conditions early Tuesday morning to douse a fire at a rural Petaluma-area home surrounded by tons of debris and junk.

Firefighters were summoned to the 1,400-square-foot stucco home, built around 1920, by neighbors' 911 calls.

Fire engines and water tenders had difficulty navigating the narrow street and were forced to park above the 4-acre property, running a 400-foot water line down a muddy unpaved drive to the home, Sonoma County Fire Capt. Bob Borges said.

Stadler Lane is a one-lane, pock-marked street off Eastman Lane about three miles west of Petaluma city limits.

The building was engulfed in flames when firefighters arrived and the structure was already damaged, he said, heightening concerns about firefighters' safety.

Compounding matters were about a dozen vehicles, a camper, a boat and junked appliances near the building, making a firefighting approach difficult.

"We were in a defensive position immediately, just spraying water on it," Borges said. "We weren't able to fight the fire aggressively. We didn't want to put firefighters in harm's way."

Pacific Gas & Electric crews responded to cut power lines to the building. It appeared other lines were connected to a second location, perhaps an outbuilding behind the home.

The owner, Lewis Honnen, 82, showed firefighters the location of the gas meter. Crews dug it out from under overgrown ivy to allow PG&E to shut it off as well, Borges said.

"There are a lot of buckets and containers with oil," he said after the flames were doused.

Inspectors found several cylinders in the remains. Hazard materials crews used absorbent pads to soak up runoff and other liquids so they didn't seep into the ground or a nearby creek.

Investigators examined the remains Tuesday trying to determine the fire's cause and origin. By late Tuesday, Borges said the cause likely will remain undetermined because the building is unsafe to investigate.

It was unclear what condition the home was in before the fire. Borges said to rebuild would likely cost $400,000 to $500,000.

Ten fire agencies and about three dozen firefighters responded to the fire.