The search continues for missing Colorado mom Kelsey Berreth. The authorities are digging through a quarter-acre of the Midway Landfill in Fountain, Colorado, in hopes of finding the charred remains of Berreth’s body.

Investigators were led to the landfill by Idaho nurse, Krystal Lee Kenney, who is thought to be the alleged mistress of Berreth’s fiancé Patrick Frazee. Frazee was charged with first-degree murder, three counts of solicitation to commit first-degree murder, charges of tampering with a deceased body, and two charges of committing a crime of violence.

The search is expected to last for at least 35 days as searchers make their way through the 686,805 cubic yards of the landfill. However, Woodland Park detectives said in a statement that the primary search area is approximately 4,320 cubic yards and will be sifted through by a team of 10 searchers.

The search will utilize an excavator to move the nine feet deep trash to another location where searchers will sift through it, Chris Adams, Woodland Park Police Commander told CNN.

"It's a slow, methodical search. We don't want to miss anything. I think we owe it to Kelsey and her family to -- to be as thorough as we can," Adams told the news outlet.

The police have focused their attention on the landfill based on information that Kenney provided. Kenney told police that Frazee burned the body of Berreth in a water trough after beating her with a baseball bat. He then disposed of her body, according to Kenney.

Depending on how the body was burned, there could be bones and tissue left behind, CNN reported. A fire could leave bones and teeth behind, where DNA could be present for identification, Natalie R. Langley, an associate professor of anatomy in the Mayo Clinic College of Medicine and Science in Scottsdale, Arizona told the news outlet.

Decomposition of the body could also be affected by animals, insects, burial depth or the weather, which could speed up or slow it down, according to CNN.

Berreth was last seen on Thanksgiving Day at a Safeway grocery store in Woodland Park, Colorado. Frazee is suspected of being the last person to see her alive.