CHARLESTON, W.Va. -- During the past six years, employees in the state Division of Homeland Security and Emergency Management have collected more than $900,000 in overtime pay, filling in at a emergency call center in the state Capitol's basement, according to an audit released Tuesday.

Homeland security workers received up to $18,000 a year in overtime, at $35 an hour, increasing their annual earnings by more than 50 percent in some cases.

A legislative audit blamed the excessive overtime on the agency's failure to hire part-time employees to work at the call center. The vacancies allowed homeland security employees -- including division managers -- to rack up overtime at high rates, the audit found.

"Over the years, most of the staff have worked and been paid at a significant costs to the state because the salaries of those working overtime are much higher than the salary of the vacant positions," said Jill Mooney, a research analyst with the Legislative Auditor's office.

About 20 homeland security employees have collected $900,478 in overtime pay since 2006, according to the audit.

The audit concluded that the Division of Homeland Security and Emergency Management spent about $580,000, or 64 percent, more to pay its employees overtime than what it would have cost to fill the call center vacancies.

Joe Thornton, state secretary of military affairs and public safety, told lawmakers Tuesday that Homeland Security has struggled to fill part-time positions at the emergency communications center, which operates 24 hours a day, seven days a week.

"When folks understand the salary, the hours they'll be working and the requirements, they have quickly, according to [Homeland Security] Director Jimmy Gianato, gotten up and walked out of the interviews," said Thornton, whose office oversees homeland security.

Gianato did not attend Tuesday's meeting to answer questions about the audit.

The emergency call center opened six years ago. The Legislature sets aside funds each year to staff the facility with six full-time workers and four part-time employees.

"The Legislature has provided the agency a line-item budget specifically and solely to fund the communications center," Mooney said.

Homeland security employees who don't normally work at the emergency call center have collected the bulk of overtime pay.

Overtime costs at the facility increased from $145,832 in 2006 to $167,802 last year, according to the audit.

Last year, 14 homeland security employees made $3,000 or more in overtime. One worker, whose salary was $34,000 a year, collected an additional $18,000 in overtime pay.

"Fully staffing the communications center would significantly reduce the cost of operating the center by reducing the need for overtime compensation," Mooney said.

Homeland security officials told auditors that the agency has tried on "numerous occasions" to fill the vacant jobs, Mooney said.

But Division of Personnel records show that Homeland Security advertised the vacancies only three times -- twice in 2008 and once in 2011.

"The legislative auditor requested the agency provide documentation of its attempts to fill the positions on [other] occasions," Mooney told state lawmakers during Tuesday's interim meeting. "The legislative auditor has not been provided with supporting evidence of other attempts."

Homeland security officials have said the agency might consider converting the four part-time positions to two full-time jobs.

"It's an ongoing process, and we're working diligently to try to address it," Thornton said.

The emergency communications center has a toll-free number that answers calls for mine disasters, environmental spills, suspected arsons, school safety concerns and whistleblower tips from mine and industrial workers.

"Not having coverage is just not acceptable," Thornton said. "It's just one of those balancing acts."

The audit also found:

Homeland security officials publicly reported that the gauges worked properly 93 percent of the time, but auditors determined that that was only a guess.

"The agency should develop a methodology to capture, measure and monitor the operational rate of its weather gauges," Mooney said. "An agency should not publicly display that it has achieved an important goal when it has no data to prove it."

Thornton said Homeland Security's flood warning system had "software issues," and the agency was working to fix the problem.

In the days after the June 29 derecho, "there was no mention of the event on the agency's Web page, and a website visitor would not have known the state was experiencing a widespread and serious event," Mooney said.

"The agency needs to view and use its website as a communication tool," she said. "The agency has not adequately used its website to communicate."

Reach Eric Eyre at erice...@wvgazette.com or 304-348-4869.