CARLSBAD, N.M. (AP) Construction work on a 600-ft.-deep (183 m) cavity in Carlsbad began in December as crews re-positioned access routes and brought materials to the site ahead of February's predicted remediation start date.

The Carlsbad Current-Argus reports the Carlsbad Brine Well, located directly underneath the South Y junction of U.S. Highway 285 and U.S. Highway 62/180, was deemed unstable in 2008, and its collapse was estimated to cause potentially $1 billion in damages and litigation.

The Wood Group was contracted earlier this year to design and implement a project to fill the cavity with grout, while pulling out the remaining brine water.

Records show the cavity is 720 ft. (219.5 m) long, 450 ft. (137.2 m) wide, 200 ft. (61 m) deep and lies about 425 ft. (129.5 m) beneath the surface.

Officials expect the entire process to take two years.

For more information, visit currentargus.com.