The utility company said Sunday it had drilled down about 3,800 feet when it found the breached well's 7-inch pipe with a magnetic ranging tool that allows workers on the surface to locate small underground targets. They are drilling a relief well nearby that they will eventually connect to the leaking well so they can plug it with cement.
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"One of the challenges in drilling this relief well is to find a 7-inch pipe from about 1,500 feet away, several thousands of feet below ground - while avoiding others nearby," Southern California Gas Co. said in a statement issued Monday. There are more than 100 such wells in the area.
Workers still aren't sure exactly where the 8,700-foot well was breached but suspect it was relatively close to the surface.
"We think it's probably leaking above the thousand-foot level," Gas Co. spokeswoman Melissa Bailey said Monday.
She added utility workers will continue to drill to the well's bottom, where they'll plug it. That work could take until March.
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Since the well began leaking Oct. 23, thousands of people in the Porter Ranch area say they have suffered headaches, nosebleeds, nausea and other symptoms from the escaping gas. The smell comes from an additive called mercaptan that is used to warn people of leaking natural gas, which is ordinarily odorless.
Southern California Gas Co. is paying to relocate those who say they are being sickened.
So far, company spokeswoman Anne Silva said, the utility has placed 2,258 families in temporary housing, while 111 others staying with family or friends are being compensated. More than 3,000 others are in the process of being relocated.
Porter Ranch is a bucolic community of large, stately homes in the foothills of the north San Fernando Valley. It is home to about 30,000 people and includes parks and hiking trails.
The gas is coming from an underground storage area more than 8,000 feet deep that can hold as much as 86 billion cubic feet.