Paul Ralph Kovacich Jr. — a former Tracy police officer — was arrested Tuesday for the killing of his wife nearly 24 years ago.

Using DNA analysis and ground-penetrating radar, investigators found at a home near Lake of the Pines — a community northeast of Sacramento near Auburn — what they think are the remains of Janet Kovacich, who vanished Sept. 9, 1982 from her Skyridge home near Auburn in Placer County.

Investigators reopened the case three years ago after urging the victim’s family and friends. With advances in forensic science and the testimony of witnesses interviewed again, investigators last week generated enough evidence for a grand jury indictment.

Kovacich, 57, was arrested without incident outside his home at 5:30 p.m. in Foresthill, located near Lake of the Pines, just as he was getting into a SUV that was being driven by his girlfriend.

He was booked into the Placer County Jail, where he is being kept without bail, and is scheduled for arraignment at 1 p.m. today.

Despite numerous interviews and searches, no trace could be found of the 27-year-old mother after she went missing. She left behind two children, who at the time were ages 5 and 7.

Kovacich told investigators that he and his wife had argued the morning of her disappearance. Investigators have long suspected Kovacich of his wife’s killing, but they could generate only sparse evidence. Kovacich has refused to talk with law enforcement about the case since he was questioned in 1982.

But Auburn police, along with county, state and federal law agencies, opened the cold case and, in March, began digging under the driveway and around the Lake of the Pines property of Kovacich’s father, Paul Kovacich Sr. Ground-penetrating radar identified three possible gravesites on the property where investigators found human remains and those of the family dog.

The human remains were sent to the Department of Justice’s Richmond lab and, on Tuesday, Kovacich was arrested after a grand jury handed down an indictment.

Kovacich served three years with the Tracy Police Department as an officer from 1971 and 1973, where he was regarded as a good officer. He served with the Placer County Sheriff’s office from 1974 through 1992, where he retired.

Kovacich is represented in the case by Auburn attorney Tom Leupp and Sacramento attorney Clyde Blackman.

n To contact reporter Phil Hayworth, call 830-4221 or e-mail phayworth@tracypress.com.