Medford police evacuated several homes on Glairgeau Circle Saturday while explosive experts removed 56 half-pound sticks of old dynamite a man discovered in the Anderson Butte area and brought back to the city to show his father.

Two houses on both sides of Steven Duffell's residence, along with the house across the street, were evacuated for about 40 minutes on Saturday afternoon as Oregon State Police troopers and Jackson County sheriff's deputies assigned to the Interagency Bomb Disposal Unit responded to the scene and removed the deteriorating dynamite from a garage freezer, said Medford Police Lt. Tim Doney.

The 55-year-old father told police his 26-year-old son, Michael Duffell, had been shooting in the rural area on Friday when he discovered a box of explosives. He brought them back to his father's residence in the 500 block of Glairgeau Circle, thinking his dad would know what to do with the items "since he had some experience with explosives through his employment," Doney said.

Steven Duffell declined to be interviewed when contacted by the Mail Tribune. Michael Duffell could not be reached for comment.

Jackson County sheriff's Detective Sgt. Colin Fagan said Steven Duffell took the cardboard box containing the old dynamite and placed it in an upright freezer in his garage before driving to the Medford police station at about noon on Saturday to contact an officer directly.

Doney and Fagan gave the elder Duffell credit for contacting the police. But Fagan said storing the dynamite in the freezer was dangerous. Dynamite degrades as it ages, which makes it increasingly unstable, he said.

"Decaying dynamite tends to crystallize," said Fagan. "And those crystals are what make it unstable."

Anything that jars, jolts or expands the semi-liquid gel encased in a cardboard tube can cause detonation, he said.

"The father was well-intended," said Fagan. "He believed he was putting the explosives in a cool, dry place. But a freezer is not a good place. Freezing causes expansion. And if that dynamite had detonated, it would have been a significant explosion."

Explosive technicians removed the dynamite with the aid of a robot. The explosives were placed in a safe vessel, transported to an undisclosed location and detonated under controlled circumstances, Fagan said.

Doney said it is not unusual to find dynamite that has been used in mining and other activities out in rural areas. There also have been several incidents where unexploded ordnance has been found in Sams Valley on land that was used for Camp White during World War II, he said.

"A lot of this stuff is very old and highly unstable," said Doney.

Fagan said anyone finding explosives of any sort should mark the location carefully, back away slowly and call the authorities as soon as possible.

"But don't use your cell phone in the vicinity. That could set it off," he said.

And do not, under any circumstances, attempt to relocate the explosives yourself, he added.

"(The Duffells) should go buy lottery tickets," Fagan said. "This was a lucky day for them."

The sheriff's department has taken over the investigation because of the location where Michael Duffell said he found the dynamite, Fagan said.

Reach reporter Sanne Specht at 776-4497 or e-mail sspecht@mailtribune.com.