San Diego

County officials Tuesday approved continued construction at the St. Vincent de Paul Emergency Center, but building will not resume for three days until further tests, ordered by the regional water quality board, on a petroleum-based liquid trapped at the site are completed.

Health Department officials had asked for a building halt Monday. But Gary Stephany, a County Environmental Health official, said his office is satisfied that St. Vincent de Paul officials are taking the proper safeguards to minimize the possibility of another underground explosion. Earlier this month, workers at the 15th Street and Imperial Avenue construction site ignited an underground explosion while boring a hole for a concrete piling.

A company hired by St. Vincent de Paul officials found traces of a petroleum-based liquid mixed with underground water. Officials believe the explosion was caused when a spark from the drill ignited the flammable liquid floating in the water.

Father Joe Carroll, director of St. Vincent de Paul Center, said the Regional Water Quality Control Board stopped construction for three days while it processes a permit for more tests of the water table.

Carroll said board members want an assurance that the oil compound will not be pumped into the city sewer lines along with the underground water at the site.

The $6.8-million emergency center is scheduled to be completed in early 1987. It will provide overnight shelter for 350 transients and will serve 1,300 meals daily. The center will also house a medical clinic.