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Tax revenue coming from shale, oil, and gas development has many states very happy, but the boom is also putting a strain on regulators. There are not enough of them to inspect all the drilling sites. Colorado, for example, has 17 inspectors for more the 47,000 active oil and gas wells. Kirk Siegler reports from member station KUNC.
KIRK SIEGLER, BYLINE: Each day, Jim Precobb(ph) of the Colorado Oil and Gas Conservation Commission logs about 400 miles in his state-owned truck.
JIM PRECOBB: It is absolutely staggering.
SIEGLER: Not just because of the mileage. See, Precobb has to supervise his agency's inspectors, but because of the workload, he's also in charge of inspecting 12,000 oil and gas wells himself.
PRECOBB: And we're going to go on up to Weld(ph) County Road 38. I have some new drilling. It's over in that area. And I have some...
SIEGLER: Drilling is everywhere in sprawling Weld County, north of Denver, which now has one of the highest concentrations of oil and gas wells in the country. Rigs are sandwiched between homes and schools and in farm fields.
PRECOBB: This has...
SIEGLER: Precobb hops out of his truck and opens a gate to inspect one of them.
PRECOBB: The inspectors will come out and they'll pop the hatch.
SIEGLER: He's looking for potentially harmful gases escaping from the well itself and for spills seeping into the ground.
PRECOBB: And all this stuff is looked at by an inspector at a glance. Just like that. In, like I said, five to seven minutes we'd assess this...
SIEGLER: Even so, all the inspectors combined can thoroughly check about 1,800 wells a year. And the newer ones that are being built and hydraulically fractured or fracked are the priority. But they also spend a lot of their time investigating complaints.
PRECOBB: Do we need to add people? Absolutely.
SIEGLER: It's a predicament not unique to booming northeast Colorado. Next door in Wyoming there are a dozen inspectors for about 60,000 wells. North Dakota has 19 field inspector looking after 6,600 wells.
JEN PALAZOLO: OK, yeah, you can go out that way and I'll go out the front door.
The lack of boots on the ground is a concern for suburban mom Jen Palazolo(ph). There's been a proliferation of new wells in and around her neighborhood east of Boulder.
PALAZOLO: And the thing is, fracking...
PALAZOLO: What Hudson?
HUDSON: Oil drill.
PALAZOLO: Oil drill.
SIEGLER: With her three-year-old son in tow, Palazolo has stopped her Kia minivan by one that according to state records hasn't been inspected for five years.
JEN PALAZOLO: Especially in areas so close to where you have a large number of children, could something major go wrong that could have been prevented if it was inspected, or is there something minor occurring that nobody is picking up on because nobody has been out here in five years to check it.
SIEGLER: The what-ifs are very much on the mind of Mike King. He's the director of Colorado's Department of Natural Resources, which oversees all oil and gas drilling. But the state budget is also a concern.
MIKE KING: It's been a constant question for us as regulators, is do we have the resources. And it's not just on oil and gas. It's mining, it's game wardens for enforcement of wildlife laws.
SIEGLER: The state is planning to hire two more oil and gas inspectors for now, and King is also asking cities and counties to hire their own inspectors, who would then report to state regulators. Now, all of this will certainly help Jim Precobb's workload.
PRECOBB: You probably have a minimum of 16, maybe 20 tanks that are right there.
SIEGLER: Back in Weld County, he says keeping pace with the boom is tough. The state moves a lot slower than industry, and hiring and training more people takes time.
PRECOBB: It's a challenge because most of the people, including myself, have not seen raises in five years.
SIEGLER: Precobb says a lot of his inspectors could be working jobs in the industry and getting paid double the wages.
For NPR News, I'm Kirk Siegler in Denver. Transcript provided by NPR, Copyright NPR.