Mare Island Naval Shipyard, Welding School, South of Thirteenth Street East of Railroad Avenue, Vallejo, Solano County, CA

Significance: This building is a contributing element of the Mare Island Historic District, having good historical integrity with approximately 90% of the original building existing. It is a large rectangular shaped building of steel and concrete utilizing an internal framework of steel columns and steel beams to support the structure and curtain walls (windows). The primary historic significance of Building 686 is its function as not only the Shipyard's Electric Shop, but as a Steam Test Plant and a Subassembly Facilities extension to Building 382, during World War II. The repair of ships was a critical shipyard activity during this period. Building 686 would have been a key element in the repair of damaged ships during World War II.
Survey number: HABS CA-1543-R
Building/structure dates: 1941 Initial Construction
National Register of Historic Places NRIS Number: 75002103