OPINION – Almost two years to the month after House Speaker Nancy Pelosi famously championed natural gas as “a clean alternative to fossil fuels,” the highly flammable petroleum product caused a massive explosion in San Bruno, killing at least four, injuring dozens and leveling more than 50 homes.

Until recently natural gas was a clean energy source darling touted as a low-carbon bridge between fossil fuels and renewable energy, but it is increasingly under scrutiny for its public safety issues and negative environmental impacts.

Environmentalists are concerned about the potential water pollution and carbon emissions associated with hydraulic fracturing, also known as “fracking,” a technique for extracting shale gas (a type of natural gas) that has become a significant source of fuel in the U.S. and whose importance is expected to grow.

While the technique is being hotly debated in the northeast along the Appalachians where a massive deposit of the gas is located, Californians nonetheless have a stake in the the conversation. They rank second only to Texas as the biggest natural gas consumer in the country.

In 2008, the state derived 45.7 percent of its electricity from natural gas-fired power plants (both in state and out of state). Some 85 percent of CA’s natural gas, which is also used to heat homes, fuel stoves and water heaters, is imported from regions – the southwest, Rockies and Canada – that use fracking.

The California Energy Commission projects that natural gas use will continue to grow and is currently reviewing 18 proposed plants for licensing.

Fracking entails breaking up shale rock, which typically exists about a mile below the earth’s surface, through small explosions that free the natural gas trapped in the rock. Companies use a combination of pressurized fluids to break open the rock.

Mounting evidence that the process can contaminate water sources and the air with methane and fracking fluid is documented in numerous news stories investigating the problem, including pieces by ProPublica, Vanity Fair, and Scientific American.

The public uproar over fracking has prompted the U.S. Environmental Protection Agency this month to ask nine mining companies to disclose the ingredients in their fracking fluids in order to determine if they are a danger to human health and the environment.

While many of the environmental hazards associated with fracking do not take place in California, as a major buyer the state can throw its weight behind best practices. According to ProPublica, new disclosure rules in Wyoming are leading the way.

Disclosure is also a hot topic as the California Public Utilities Commission investigates Pacific Gas and Electric, the massive utility whose faulty equipment caused the San Bruno disaster. The CPUC has ordered PG&E to check all of its natural gas pipelines in the state for possible leaks and disclose how much it has spent on repairs and safety since 2005, according to The Chronicle.

Beyond immediate risks, there’s discussion of changing the location of potentially dangerous pipelines. The Wall Street Journal reported that “Brigham McCown, the former head of the federal Pipeline and Hazardous Materials Safety Administration, the federal pipeline regulator, in an interview called for creation of a national commission to examine the problem of high-pressure fuel pipelines that pass through residential areas, as well as near schools and other public facilities.” One possible solution would be to relocate particularly dangerous pipelines to unpopulated areas.

It has take a tragedy for Californians to consider possible new safety standards for the natural gas delivered to their homes, they should not wait for such terrible news before examining the sources of the natural gas they consume.

Tags: fracking, hydraulic fracturing, natural gas, san bruno