If you live in an oil-and-gas state, you may well find databases at state agencies that will help you develop stories about the environmental impacts of drilling and spills in your area. The Denver Post searched an online database of Colorado oil and gas operations and found thousands of spills — ranging from minor to major — in that state.
"Oil and gas companies have reported almost 1,000 spills to Colorado regulators over the past 2 1/2 years, totaling 5.2 million gallons of drilling liquids and oil," wrote Post reporter Burt Hubbard.
Hubbard searched online records available to the public on the site of the Oil and Gas Conservation Commission. The database contained information about lots of other things besides spills — including inspections, financial responsibility, production, and the amounts owed and paid to the state (hint: some well owners are behind in payments).
It is worth noting that a big fraction of the leaks and spills involved not merely oil, but produced water containing hydraulic fracturing fluid.
The data situation will be different in different states. Check with the state agency that oversees drilling, but also with your state environmental, resources, and mining agencies. Look also for air and water discharge permits.
- "Millions of Gallons Spilled in Colo. Over 2½ Year Period,"  Denver Post, June 28, 2010, by Burt Hubbard.