Posted by Big Gav in oil
The bright yellow signs on U.S. 285 are the first indication that things aren't right in Carlsbad. "US 285 south subject to sinkhole 1,000 feet ahead," motorists are warned.
But there is little other evidence that in southeastern New Mexico's oil country, a giant cavern sits beneath the earth, ready to swallow part of the highway and possibly a church, several businesses and a trailer park.
The cavern was formed over three decades as oil field service companies pumped fresh water into a salt layer more than 400 feet below the surface and extracted several million barrels of brine to help with drilling. State regulators flagged it as a potential danger after concluding that it was similar to two wells northwest of Carlsbad that collapsed without warning last year.
Over the past few decades, communities in Texas, Kansas, Michigan, Canada and Europe learned of similar underground danger only after cracks appeared and the ground began to sink. Regulators are trying to determine how to prevent future collapses by better managing a practice that's used throughout the world.
Most brine wells operate far from homes and businesses, but Carlsbad's is unique because it is in a population center — and could prove potentially disastrous.