The Corps of Engineers and the Dredge Material Management Office conducted the tests, which have been ongoing since the Cosco Busan container ship leaked 58,000 gallons of fuel into the Bay after crashing into a San Francisco-Oakland Bay Bridge tower.
Friday’s testing was meant to give more extensive results of the amount of possible oil in the dredging area within the Oakland Outer Harbor Channel.
Dredging gathers sediments that collect at the bottom of the Bay to widen and deepen the Bay and make the waters navigable for large ships, spokeswoman Maria Lee said.
Materials collected during dredging are often reused in areas such as wetlands and other ecologically sensitive areas, Lee said.
Making sure the materials are not contaminated is key, as dredging in contaminated areas could have ecological impacts on areas using the materials and on the Bay itself, Lee added.
Dredged materials are always tested before reuse, according to Lee, but the testing done Friday was more extensive because of the recent oil spill.
Oil-absorbent pompoms were dragged along the bottom of the Oakland Outer Harbor Channel twice Friday, and both tests were clear and did not find any oil, spokesman Joe Barison said.
The area is now considered safe for dredging, he said.