It’s been a busy couple of weeks in the fracking and natural gas drilling debate, with the documentary film Gasland nominated for an Academy Award and a front-page story in Sunday’s New York Times on the dangers posed by the technology.

The Times story underscored the findings of dozens of reports that ProPublica has published over the past three years, adding new details from previously undisclosed government documents about the amount of radioactive water produced by drilling.

The increasing public interest in the possible dangers of gas drilling comes as the world’s energy companies are placing a multi-billion dollar bet on its potential. At the request of Vice President Dick Cheney, Congress exempted gas drilling from federal regulation in 2005. Since then, industry officials have successfully lobbied against calls in Washington to change the law, calls that have intensified in recent months with new attention on the issue.

For those who want to dive deeper into the complex science and regulatory issues of fracking, we offer a quick breakdown of the key issues.

It’s a subject reporter Abrahm Lustgarten has been covering for ProPublica since July of 2008. In the years since then, Lustgarten and his ProPublica colleagues have criss-crossed the country, interviewing drillers, industry officials and residents from Wyoming to Colorado to Pennsylvania. To listen to a podcast from Lustgarten, click here. To read a detailed account of one man’s fight against water contamination in Wyoming, click here. (Lustgarten received the 2009 George Polk Award for environmental reporting for his investigation of hydraulic fracturing as well as the 2009 Stokes Award for Best Energy Writing from the National Press Foundation.)

Below is a list of 15 of our most important stories, arranged by topic so you can quickly find the information you need. For a list of all the 100 or so stories we’ve written about gas drilling since 2008, you can also visit our gas drilling home page.

Radioactivity

• Is Marcellus Shale Too Hot to Handle? – A 2009 analysis of wastewater samples from wells in New York showed levels of radioactivity more than 250 times the federal drinking water standard.

Wastewater

• With Natural Gas Drilling Boom, Pennsylvania Faces an Onslaught of Wastewater – As gas drilling expanded in 2008 and 2009, Pennsylvania regulators were unprepared for a wave of contaminated wastewater.
• Drilling Wastewater Disposal Options in N.Y. Report Have Problems of Their Own – This December 2009 investigation showed that none of the disposal options laid out in a state report on gas drilling was realistic.

Methane Contamination

• Officials in Three States Pin Water Woes on Gas Drilling – As new drilling expanded across the country, cases proliferated of natural gas leaking into water wells.
• Water Problems From Drilling More Frequent Than Pa. Thought – Methane related to the natural gas industry has contaminated water wells in at least seven Pennsylvania counties since 2004.

Overview

• Buried Secrets: Is Natural Gas Drilling Endangering U.S. Water Supplies? – A 2008 investigation found more than 1,000 cases of water contamination in drilling areas around the country.
• New York’s Gas Rush Poses Environmental Threat – As state legislators looked to fast-track gas drilling permits in 2008, this investigation revealed environmental harm from drilling in other states and looked at how drilling might affect New York’s waters.
• What We Don’t Know – A look at the basics of hydraulic fracturing and gas drilling from December 2009.
• How the West’s Energy Boom Could Threaten Drinking Water for 1 in 12 Americans – An examination of the threats posed by oil and gas drilling in the Colorado River Basin.

Regulation

• State Oil and Gas Regulators Spread Too Thin – As gas drilling expanded across the country, state agencies failed to keep pace by hiring more inspectors, leaving some wells uninspected for years.
• Underused Drilling Practices Could Avoid Pollution – Innovative industry solutions that would use less water and reduce air pollution have not played a prominent role in the national debate over how to drill safely.
• In New Gas Wells More Chemicals Remain Underground – A December 2009 investigation showed that despite previous reports, as much as 80 percent of hydraulic fracturing fluids can remain underground.
• Energy Industry Sways Congress With Misleading Data – As the industry tried to pre-empt stronger federal regulation, it used arguments that were undercut by its own data and reports.

Air Pollution

• Climate Benefits of Natural Gas May Be Overstated – New emissions estimates by the Environmental Protection Agency cast doubt on the assumption that gas offers a quick and easy solution to climate change.