Airborne asbestos halted work for two days within a two-week period last month at a prominent southeast San Francisco construction project.
Asbestos, which can cause deadly lung diseases, occurs naturally in Bay Area serpentine soils, including those at the shuttered Hunters Point Naval Shipyard.
Construction on the infrastructure of a 63-acre site at the edge of the shipyard, where the building of 1,600 homes could begin in April, was halted after elevated levels of asbestos were detected.
Air monitoring stations detected asbestos at twice the allowable level Feb. 16 and Feb. 26, according to Bay Area Air Quality Management District spokesman Ralph Borrmann.
The allowable level is set at a low threshold to protect human health, according to Borrmann.
“While no project likes to be subject to delays, we think that the public health issues must take precedence,” said Michael Cohen, Mayor Gavin Newsom’s chief economic development adviser.
Elevated levels of asbestos were last detected by the air monitors in late October, city health data shows.
Such detections of elevated asbestos automatically trigger one-day work shutdowns at the high-profile site.
“The city of San Francisco made a policy decision that we would subject this project to delays in order to be hyperconservative in our protection of human health,” Cohen said.
The elevated asbestos levels were likely caused by roadwork and exacerbated by strong winds, according to Sam Singer, San Francisco spokesman for master developer Lennar Corp.
“The company works very hard to eliminate as much dust as humanly possible,” Singer said.
Source: Bay Area Air Quality Management District