Whistle-blowers who allege a Utah radioactive-waste site did shoddy work for the federal government can proceed with their 2003 lawsuit after an appeals court reinstated the case Wednesday.

The Denver-based 10th U.S. Circuit Court of Appeals ruled three former workers at Envirocare of Utah had adequately documented dozens of alleged instances when the company, now EnergySolutions Inc., had improperly requested payment from the federal government for substandard work.

The court said U.S. District Judge Bruce Jenkins in Salt Lake City should not have dismissed the case last year in light of the detailed logs the workers kept of alleged safety, health and environmental lapses in violation of their contracts.

EnergySolutions has denied the whistle-blowers’ charges. Its attorney, Rod Snow, said he had not had an opportunity to read the ruling and was uncertain whether to challenge the decision. If not, he added, “we will defend it on the merits.”

Meanwhile, Jeb White, former president of the Washington, D.C.-based group, Taxpayers Against Fraud, called Wednesday’s ruling significant.

“Without whistle-blowers,” he said, “the government is not able to get the evidence it needs to prosecute these cases” under the False Claims Act.

Under the Civil War-era law, more than $7.8 billion has been returned to the government since 1986, according to White’s group, which tracks such cases and advocates whistle-blower protections.

Utah attorney Steve Russell said Wednesday’s ruling opens the door for his clients to go nose to nose in court with EnergySolutions over additional invoices, reports and other documents that they expect will bolster their case. Many of their allegations arise from notes kept over two years by one-time night foreman Roger Lemmon and colleagues Patrick Cole and Kyle Gunderson.

Lemmon’s widow now is the lead plaintiff. Her husband died after filing the lawsuit in 2003.

“I predict they [at EnergySolutions] are going to fight us on everything we ask for,” Russell said. “It’s going to be a long and bloody battle.”

In addition, the whistle-blowers’ attorney said, the three federal agencies that contracted with Envirocare — the Defense Department, the Energy Department and the Environmental Protection Agency — might reconsider joining the suit and, in effect, become a partner in it. Those agencies heard the allegations in secret in 2002 and opted against joining the lawsuit at that time.

The government long has been a big customer at the Tooele County site, the engineered burial ground for more than 96 percent of the low-level radioactive waste disposed of in the past 20 years. The lawsuit essentially alleges the company violated hundreds of millions of dollars in contracts by improperly certifying that it safely and properly disposed of waste.

In Wednesday’s ruling, the court noted “pertinent contracts explicitly state that if Envirocare fails to live up to all of its contractual obligations, the government might refuse payment.”

The appeals court said the allegations were made in a “clear, organized and relatively concise manner.”

“Plaintiffs also offered a detailed description of Envirocare’s alleged efforts to conceal the violations,” the court wrote, “including, for example, the names of the Envirocare supervisors who instructed one plaintiff to stop documenting the violations.”