Olsen had long been haunted by the mining disaster, which is memorialized by a poignant sculpture near the mine along Interstate 90. When he began researching the story, he was surprised to find that no comprehensive account existed. He spent four years interviewing 200 survivors, family members, executives, government regulators and others, and his book weaves in the story of what was going on at home while the fire was burning in the mine.

Olsen writes about the macho world of the miners, where excessive attention to safety was considered unmanly. Many miners didn't bother learning how to use respirators or other safety gear, preferring to spend their time earning money. Mining safety laws at the time were lax and rarely enforced.

Bob Launhardt, in charge of safety at the mine, is a somewhat tragic figure, haunted by the fire.

The cause has never been established, but Launhardt is certain that insulating foam sprayed in the mine was flammable and created the extremely toxic smoke. He believes the federal government never really wanted to know the cause, to avoid lawsuits.

"Clearly, when so many die on your watch, it isn't easy to let go," Olsen wrote of Launhardt, who still lives in Pinehurst, Idaho. "Now in his 70s, he is an old man with perfect posture and piles of information to prove that what happened so long ago could have been averted."

The fire led to the abolition of the U.S. Bureau of Mines, which was considered too friendly with mining companies, and led to the creation of new agencies more concerned with worker safety. Reforms such as enclosing elevator operators in airtight compartments, so they would not be disabled by smoke, and requiring miners to carry personal respirators, were the result of the disaster.

The Sunshine Mine produced more than 350 million ounces of silver during a history that began in 1884 with the discovery of the Yankee Lode. The mine operated for decades after the fire, but low silver prices led to its closure in 2001.

Prices have rebounded and the mine is slated to reopen later this year.