CRESCENT CITY, Del Norte County (CBS / AP) ― Tsunami cleanup operations were winding down at Crescent City on Monday after crews raised the last sunken boat.

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The U.S. Coast Guard had been working with the state to clean up the Crescent City harbor since massive waves generated by the magnitude-9.0 earthquake in Japan caused nearly $20 million in damage there.

The March 11 tsunami sank more than a dozen vessels.

Crews pulled up the final boat, the fishing vessel Ge Ge, over the weekend — although the boat couldn’t be salvaged.

Coast Guard spokesman Erik Swanson said that divers would next be surveying the sea floor to determine if any debris or pollution is left.

Last week, California Gov. Jerry Brown asked the federal government to provide recovery relief to Del Norte County and five others: Santa Cruz, Humboldt, Mendocino, San Luis Obispo and San Mateo.

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