State regulators in California declared Thursday that the natural gas pipeline rupture in Porter Ranch is now permanently sealed, about four months after a massive methane gas leak affected the area.
Thousands of Los Angeles citizens were displaced due to the methane leak, which accounted for a quarter of total daily methane emissions in the state. A series of laboratory tests on Wednesday confirmed that the leak has been successfully sealed.
"Gas emissions are controlled and air quality has returned to normal levels," said Chief Deputy Director Jason Marshall of the state's Department of Conservation.
The leak had originated from a broken injection-well pipe located deep beneath the surface of the Aliso Canyon natural gas storage field. The Southern California Gas Co.-owned storage field is about 3,600 acres (1,457 hectares) in size.
Since Oct. 23, the leak has spewed about 96,000 metric tons of methane, a more powerful greenhouse gas than carbon dioxide. The event was ranked as the largest discharge on record in California as it poured out 125,000 pounds of methane an hour, equivalent to the impact of 8 million tons of carbon dioxide.
Thousands of homeowners were forced to evacuate and leave their homes as the stench of fumes sickened people for weeks. Residents complained of nausea, headaches, nosebleeds and dizziness.
The leak also potentially caused the SoCal Gas billions in claims, media reports said.
Sempra Energy, the parent company of SoCal Gas, expects the bill to fix the leak, relocate 6,400 residents and account for all the gas lost will be worth $300 million. This doesn't cover potential lawsuits.
Some residents expressed concern about a potential repeat blowout or the long-lasting leak's effects on the air.
Uriel Rosoff, a resident of neighboring Chatsworth, said his adult daughter had to evacuate his house because of respiratory problems, migraine headaches and nosebleeds.
He said he wanted to be assured that safety valves were indeed placed on wells in the Aliso Canyon facility, especially because the leaking well once had a safety valve removed in 1979 but was not replaced.
"I don't know what to believe," said Rosoff. "I'm skeptical of the other 114 wells up there that have been there anywhere from 30 to 70 years."
Officials, however, reassured that it is now safe for Los Angeles residents to return to their homes.
Those temporarily staying in short-term housing have eight days to return home before SoCal Gas stops reimbursing them for their emergency sublets. Those who rented a house or an apartment will have their leasing costs covered until the end of April.
Photo : Earthworks | Flickr
