A crude oil storage tank sits behind a fence at a petroleum extraction site, in Weld County, near Mead, Colo., Monday, Feb. 13, 2017.

Brennan Linsley/AP

Colorado slapped oil and gas drillers with nearly a half million dollars in penalties in the last three months.

In total, $459,353 was spread across just four companies in the third quarter of 2017, according to data from the Colorado Oil and Gas Conservation Commission.

Some of the state’s largest drillers were hit with fines. Hunter Ridge Energy Services, a subsidiary of Encana, received a $222,500 fine. That stems from a spill that contaminated water and soil near a ranch used for big game hunting.

Noble Energy, the number two oil driller in the state by volume, received a $40,096 fine when the company did not file paperwork verifying the integrity of an injection well in Weld County.

The Colorado Oil and Gas Conservation Commission has stepped up enforcement in recent years, issuing an average of $1 million in fines per quarter since 2015. Penalties were increased by state lawmakers in 2013, granting COGCC the power to issue bigger fines. Since then, they’ve handed out an unprecedented $12,693,534 in penalties.

Typically smaller operators are hit with the largest financial penalties, in part because they lack the resources to comply with Colorado’s strict regulations. But this quarter only two small drillers, Petroglyph Operating Co. and Geotech Production were issued fines, and most of the penalties were suspended. The state will usually give drillers a break if they come into compliance.

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