PG&E Stumped on Source of Underground Fire

 Pacific Gas and Electric Co. crews have been working around the clock for a full week to repair underground equipment that was damaged during an  electrical fire in San Francisco's Tenderloin neighborhood last Friday.

Since the fireball erupted from a manhole at O'Farrell and Polk streets crews have cleaned and replaced a large amount of equipment.
     
"We've made significant progress," company spokeswoman Katie Romans said.

First, they blasted water underground and vacuumed it back up to clean the soot. Then they started work to replace a considerable  amount of cable, three switches and three transformers.

The transformers were originally about 25 feet away from the manhole that was spewing black smoke for hours.

However, Romans said she could not estimate how far the fire stretched underground, or if the transformers are what caused the black smoke.

Four blocks were closed for the repairs for days after the fire, but today two blocks continue to remain shut.

Romans said crews will most likely be working all weekend.

On the day of the fire, crews rescued people from elevators that lost power and initiated a shelter-in-place for hours because the billowing smoke was toxic.  Nearly 4,000 customers lost power.  Some people didn't get it back for 30 hours.

Romans said investigators still don't know what sparked the fire.