SALINAS (CBS SF) — A current prison inmate has pleaded guilty to the 1982 murder of a Seaside woman, Monterey County District Attorney Dean Flippo announced Friday.

Alfred Powell, 62, currently an inmate at the California State Prison-Solano in Vacaville, pleaded guilty to second-degree murder for the Dec. 9, 1982 killing of Sandra Steppuhn.

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Prosecutors said Steppuhn was a 32-year-old mother of three daughters.

On Dec. 9, 1982, Steppuhn, who was also known be her maiden name of McGee, borrowed a car from a friend so she and her roommates could go out for the evening.

On her way home from picking up the car, she gave a male hitchhiker, identified in 2016 by her roommates as Powell, a ride.

Her roommates ended up canceling their plans, but Steppuhn decided she still wanted to go out for the evening and told her roommates she was going to drop the hitchhiker off and was then go to go to a bar, prosecutors said.

She left with the hitchhiker and never returned home.

Steppuhn was reportedly last seen that night between 9:30 p.m. and 10 p.m. at a Quik Stop on Fremont Street in Monterey.

A clerk at the store reported Steppuhn came into the store and bought gas while a man remained outside with the vehicle.

Steppuhn’s father reported her missing on Dec. 11, 1982.

Prosecutors said the vehicle she borrowed was discovered abandoned in February 1983 at the former Del Monte Hyatt House, which is now the Hyatt Regency Monterey Hotel.

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In September of 2015, landscapers digging in a yard on Third Street in Monterey located skeletal remains buried on the property.

The remains were identified as Steppuhn’s.

Prosecutors said Powell was living on the property at the time of Steppuhn’s disappearance and was working for the homeowner as a gardener.

On March 4, 1983, Powell was arrested for the murder of 30-year-old Suzanne Kay Nixon, a hairstylist from Pebble Beach.

Her body was found in the garage on the Third Street property.

In September of 1983, Powell started serving a sentence of 15 years to life in prison for Nixon’s murder and has remained in custody since, prosecutors said.

Powell was formally charged with Steppuhn’s murder in June of 2016, and had a jury trial scheduled to begin on Monday.

On January 26, Powell will be sentenced to a term of 15 years to life in prison for the second-degree murder of Steppuhn, prosecutors said.

He is currently serving a separate term of 15 years to life for the murder of Nixon.

Prosecutors said the two sentences will run consecutively, and Powell will remain in prison for the remainder of his life.

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