(05-06) 16:40 PDT RICHMOND - -- Crews contained a toxic chemical leak on the shores of San Pablo Bay at the north end of Richmond today as officials launched an investigation into why it took so long for authorities to be notified about the spill.

Managers at Reaction Products at 840 Morton Ave. near Parchester Village in Richmond noticed a leak from a tank at about 8:15 a.m. Monday. Reaction Products called in Clean Harbors Environmental Services to clean it up. The spill had apparently occurred when thieves broke in to the facility and tampered with the tank.

However, the environmental cleanup firm determined that the spill was actually a toxic substance called toluene and notified the Contra Costa office of emergency services, which called the Coast Guard at 11:09 a.m., nearly three hours after the spill had been discovered.

The Coast Guard recommended that Contra Costa hazardous materials personnel issue a shelter-in-place order about 1 p.m. for residents of the neighborhood.

Now, said Coast Guard Lt. Lauren Kolumbic, authorities want to know why it took so long to put out the alarm about a toxic chemical spill. "We are not talking blame," she said, "but an investigation is under way."

Today, cleanup crews collected about 7,300 gallons of toluene mixed with salt water. Crews have put up booms to contain the leak, which is near an environmentally sensitive marsh, and expect the finish the cleanup in two or three days.

E-mail Carl Nolte at cnolte@sfchronicle.com.