Larkspur Man Gets Short Jail Term for Hash Oil Explosion in San Anselmo

A 23-year-old Larkspur man was sentenced to 29 days in jail this week for a hash oil explosion and subsequent fire in February that burned him, his younger brother and the garage of his parents' Tunstead Ave. home.

Addison Zweig had already served 12 days in jail and received credit for those days, so he will only serve 17 days and will do so on parole as part of the Marin County Sheriff's work program, according to his attorney Douglas Horngrad.

Horngrad said Zweig felt that the settlement was fair. 

"He is looking forward to going to college in the fall," he said. "He and I both think that it was a positive resolution for him, and he is relieved that the process is over."

Zweig and his 20-year-old brother Elliot were arrested on the heels of a Feb. 28 explosion and fire at 196 Tunstead Ave. in San Anselmo in a garage at a home owned by their parents. The incident sent both men to Kaiser Permanente Medical Center with burn injuries. 

Based on interviews with the two men, the Marin County District Attorney's Office decided not to pursue charges against Elliot Zweig, according to Deputy District Attorney Sean Kensinger. But Addison Zweig was accused of using butane gas to withdraw concentrated THC out of cannibis to make hash oil, and he faced a maximum of 7 years in prison if convicted of felony manufacturing of illegal narcotics. 

Zweig also originally faced charges of maintaining a place where narcotics are manufactured, possession of concentrated cannibis, unlawfully causing a fire and possession of a controlled substance. Some of the charges resulted from a search of the brothers' apartment in the Larkspur Landing area.

Zweig struck a plea deal last month, admitting to two charges, drug possession and maintaining a site for drug manufacturing.

He was sentenced by Marin County Superior Court Judge James Ritchie. 

Ross Valley Fire Department personnel responded to the Feb. 28 incident to find the garage adjacent to the house was ablaze. Elliot and Addison Zweig sustained first-degree burns to the face and second-degree burns on his arms, respectively, according to fire officials.

An ensuing investigation by the Marin County Major Crimes Task Force established evidence that the men were allegedly engaged in making “honey oil,” an extract from marijuana, according to Sgt. Pierre Ahuncain.

Ahuncain explained that the process involves the use of butane gas and “there were dozens of cannisters” in the garage. He said a build-up of butane gas in the garage, which had poor ventilation, was probably triggered by an unknown source of ignition. 

Ahuncain said honey oil has grown in prevalence over the past year or two; it is similar to hashish oil but more potent.