Ohio has few checks for natural-gas storage leaks


By Laura Arenschield
The Columbus Dispatch  •  Thursday January 14, 2016
A vast, underground natural-gas storage field in California has been leaking methane for 10 weeks, forcing thousands of people from their homes and raising concerns about its effect on climate change.

The leak has residents in other states worrying about storing natural gas underground until it can be shipped and used to heat homes and power gas stoves.

In fact, Ohio ranks eighth nationwide in the volume of natural gas stored below ground.

California officials issued emergency-oversight measures last week requiring daily inspections of storage fields using infrared technology to catch leaks.

In contrast, Ohio relies on annual visual inspections by state workers and asks the companies that operate the storage fields to catch any methane leaks.

Ohio has about 3,000 natural-gas wells that are connected to about two dozen storage fields, including one of the largest in the nation.

That field, operated by Dominion East Ohio in Stark County, can hold as much as 59.4 billion cubic feet of gas — enough to fill Hoover Reservoir nearly three times. In all, the underground natural-gas storage capacity in Ohio could fill Hoover Reservoir 210 times.

The Ohio Department of Natural Resources, which regulates the wells and storage fields, has no records of any leaks, said Eric Heis, a department spokesman.

The department has about 50 inspectors, who visually inspect wells once a year.

But methane is odorless and colorless and usually requires infrared technology to detect.

“That’s kind of the scary thing about it, and the thing that allows it to go under the radar, is that you can’t see this when it’s leaking,” said Melanie Houston, director of water policy and environmental health for the advocacy group Ohio Environmental Council.

“I think some people don’t even know if they live in proximity to a storage facility — it’s underground and it’s at a great depth, and so you very well may be at risk.”

People in California could smell the leak from the Aliso Canyon storage site because the gas had been treated with mercaptan, an additive companies add to natural gas that alerts people to problems. But not all storage fields contain gas treated with mercaptan.

Heis said companies in Ohio monitor pressure at natural-gas storage fields for any changes that would indicate a leak. But they are not required by the state to do so, nor are they required to report leaks. Natural Resources is working on rules that would require companies to report leaks, he said.

It’s in the companies’ best interest “not just to prevent leaks but to keep their gas in. It’s a very valuable resource,” Heis said.

“We believe we’re ahead of the curve on a lot of safety issues and safety concerns,” he said.

Methane leaks can create a fire hazard, and natural gas can contain benzene, a known carcinogen. The fumes are blamed for nausea and nosebleeds among those forced from their homes in California.

Amy Townsend-Small, an assistant professor at the University of Cincinnati who researches methane emissions in natural gas, said the Aliso Canyon leak is unusual.

She said the biggest threat from an underground natural-gas storage leak is its effect on climate change. Methane is a greenhouse gas.

The California well is pumping as much as 25 percent of the state’s daily methane emissions into the air, according to some estimates.

Townsend-Small also said the risk is a bit of an unknown.

“We don’t necessarily know how often this could be happening in a place where the gas isn’t odorized,” she said. “It’s so easy for them to go undetected.”