The North Regional Major Crimes Tash Force (NORTAF) Forensic Team returned to the property in the 1400 block of Orchard Lane in Northbrook on Thursday morning, Northbrook police said in a statement.
Police said they have excavated the yard to a depth of about three feet, and work may continue into the weekend due to the detailed nature of the investigation as well as "soil condition challenges."
Police confirmed the missing woman linked to the cold case investigation was Linda H. Seymour. The 35-year-old woman was last seen on December 21, 1982 in Northbrook.
Police are acting on a tip that led them back to the home, which was Seymour’s last known address, but they have not given any further details. They have only said there is no threat to the public.
The current property owner is James Seymour, Jr. Neighbors say he is Linda's son.