Greeley surrounded by 20,000 oil and gas wells.

GREELEY Colo. — This is a town running on oil. From dawn till dusk, trucks carrying men and machinery rumble away for the oil and gas fields. About 425 wells are tucked within the city limits;..and that number is expected to grow to 1,600 in coming years. A vacant patch of grass near graduate student housing on the city's east side bears this sign: “Future Drilling Site.”

“These wells are going to be here for a long time,” said Wendy Highby, a librarian at the University of Northern Colorado who joined a group of residents to oppose the project . “They’re what we’re leaving to our children.”
 Read NY Times article: Supporting Oil and Gas, but Resisting Encroachment'

On May, 29, 2013, 100 barrels of brine water spilled to the ground, just 160 feet from the river. One barrel is 42 gallons. A valve on the tank had failed. 

See:  Colorado Oil and Gas Conservation Commission  database ( May, 29, 2013 ).

Diesel smoke is spewed in big puffs 120 times an hour;
2880 times in 24 hours, for 5 to 8 days per well.
22 wells are planned at Island Grove