Three donated truckloads of concrete and three hours later, a 28-foot-deep mine shaft in a popular outdoor area near Gold Canyon became just a bad memory Monday morning.
Employees of concrete producer CalPortland, volunteering their time, also closed two smaller shafts and six shallow prospecting holes dug decades ago. The site is just a few hundred feet from a dirt road leading to the Peralta Trailhead into the Superstition Mountains.
Doug Anderson, CalPortland's vice president and general manager in the Phoenix region, said it was an easy call to lend a hand after his company received an e-mail in which State Mine Inspector Joe Hart asked for help.
"You can see someone with a four-wheeler, a horse or hiking around here, and you can tell how dangerous it is," Anderson said.
With Arizona's budget under strain, Hart is encouraging more companies to volunteer to fill in some of the thousands of abandoned mine shafts around the state that are considered dangerous.
"We're looking at a $1.8 billion shortfall, and the only way we can get the kind of funding to fill these kinds of holes is through the private sector," Hart said.
Officials have documented about 100,000 abandoned mine shafts around Arizona, Hart said. About 9,000 of those shafts are considered dangerous because of their depth and their proximity to communities and recreation areas.
Two people have been killed falling into open mine shafts in the past 13 months: a 13-year-old girl riding an all-terrain vehicle near Kingman and a 19-year-old man who had stepped away from a campfire near Cave Creek.
Hart and 13 CalPortland managers were out before sunrise pouring concrete into the abandoned mercury mine.
CalPortland donated more than $4,000 in materials, while the Department of Mines and Mineral Resources took care of permits required to fill the shaft.
After pouring concrete into the shafts, crews covered them with rocks and earth.
"When we leave, we don't want it to look like anything was ever here," Anderson said.
Steve Trussell, executive director for the Arizona Rock Products Association, said it's important for more companies to follow CalPortland's lead.
"This is a legacy that gives the industry a black eye," Trussell said.
Hart said he is talking to a couple of other companies about volunteering manpower and materials to close mine shafts.
"CalPortland really stepped up to the plate. ... We just can't do it without that help," he said.