NEW YORK (AP) - The bulldozer was clearing land outside a day care center in Hapeville, Ga., when it broke open a buried 1-inch pipeline. The escaping gas ignited into a fireball that killed nine people, including seven children settling down for their afternoon naps.
That was 1968. Since then, there have been at least 270 similar accidents across the country that could have been prevented or made less dangerous by a valve that cuts off leaking gas and costs as little as $10-$15 for homes and small businesses and $200-$300 for larger buildings, an Associated Press investigation found.
Yet nearly 90 percent of the nation's gas service lines aren't fitted with the valves. Despite persistent government recommendations, the gas industry has argued that they are unreliable and cost too much to install - $207 million over 50 years in one industry-commissioned study, more than $1 billion in another estimate.
In the meantime, the accidents continued: Since Hapeville, at least 67 people have been killed and more than 350 hurt in accidents where the valves could have helped but weren't installed. Six people were killed in a Minnesota store blast in 1972. A 25-story Manhattan building was destroyed in 1974, injuring 70 people. Four people died and six buildings were leveled in an explosion in 1998 in St. Cloud, Minn.
"There were lives lost that did not need to be lost," said Robert Hall, deputy director of the National Transportation Safety Board, which is responsible for investigating pipeline accidents.
The NTSB recommended the valves 16 times, but only in 2009, under pressure from Congress, was a rule approved - to make the devices mandatory only on lines leading to new, single-family homes. Now, regulators are considering expanding that to new or replaced pipelines serving millions of multifamily homes and commercial buildings. And the utilities are objecting.
"NTSB has made excess flow valves some kind of holy war where they think everything should have a valve on it," said Don Stursma, an official at the Iowa Utilities Board who sits on an advisory board to the Pipeline and Hazardous Materials Safety Administration.
Pipeline agency officials say they will decide whether to push ahead with the new rules sometime next year.
The valves are designed to trip automatically when there is a break in a service line, the narrow-diameter pipes that serve individual homes and businesses. A sudden rush of escaping gas pushes a small, spring-loaded stopper inside the valve, plugging the line.
Without them, gas can leak unchecked into a building or house, pooling until an ignition source - turning on the stove, a pilot light in the water heater, even an electrical spark from a cellphone - triggers an explosion or fire.
The most complete government records, covering 2004 to the present, showed 187 accidents that potentially could have been avoided or mitigated, according to the AP's review.
That includes 148 cases the U.S. Transportation Department said could have been averted or diminished if valves were in place. The department released details on those accidents in response to a public records request from the AP. Applying the agency's criteria, the AP found 39 more. Another 84 cases were identified by NTSB investigators or mentioned in Transportation Department studies.
There are more than 66 million natural gas service lines in the U.S., but only about one in 10 had excess flow valves, according to the government's most recent data. Almost 46 million new service lines have been installed since 1970 - about 39 million without excess flow valves. That's about 39 million "missed opportunities," as Hall put it.
The federal pipeline safety agency, which sets pipeline rules, announced last year that it was considering requiring the valves for multifamily dwellings and commercial buildings. The agency believes the 2009 mandate for safety valves on single-family homes "only partially addressed" the NTSB's recommendations, agency spokeswoman Jeannie Layson said in a written statement.
Before the agency decides whether to go ahead with new rules, officials want to survey companies about how much it might cost them to place excess flow valves on service lines for buildings along with new, single-family homes, Layson said.
Manufacturers and utilities say the cost per valve could be as low as $10-$15 for homes, retail businesses and restaurants.
For larger buildings, such as large commercial or small industrial businesses and institutional buildings such as libraries, the cost can climb to $200-$300, according to GasBreaker Inc., a Pennsylvania-based manufacturer.