Asbestos Exposure at Mare Island Naval Shipyard

By David Meldofsky, California-licensed attorney · Founder, Lawsuit Informer

Last updated: September 7, 2026

Mare Island built submarines, and later it spent decades taking them apart and putting them back together. Both jobs meant working inside a steel tube with insulation on every pipe and no room to step away from it. The yard ran until 1996, which makes it different from most naval facilities: someone who worked there in the 1980s is only now reaching the years when asbestos disease appears. This page covers how the exposure happened, who it reached, and why the yard's late closing date matters.

About Mare Island Naval Shipyard

Mare Island sits in Vallejo, California, about 25 miles northeast of San Francisco. The Navy started building there in September 1854, making it the first naval shipyard on the West Coast, and it ran for 142 years until closing in 1996 under the federal base closure process. Part of it is now a National Historic Landmark district. Over that span the yard built more than 500 vessels and overhauled thousands more.

The yard peaked during World War II with a workforce of roughly 46,000, turning out submarines, destroyer escorts, and landing craft. In its last 25 years it was the leading submarine port on the West Coast. Through every one of those decades, asbestos was ordinary shipbuilding material, which is why so many people who worked there were exposed.

Why Asbestos Was Present

Submarines were the yard's defining work, and a submarine is the worst possible place to disturb asbestos. Insulated piping, machinery lagging, gaskets, and packing all had to fit inside a pressure hull with almost no spare volume. Dust raised in one compartment went everywhere and stayed. For the general background on why ships were built with these materials, see asbestos exposure in shipyards and naval service.

Where Exposure May Have Happened

The yard's exposure settings reflect its submarine specialty alongside its surface-ship work:

• Inside submarine pressure hulls during construction, where trades worked shoulder to shoulder in unventilated compartments
• Submarine overhauls, when original machinery insulation was stripped and replaced inside the same confined spaces
• Engine room and machinery compartment work on both submarines and surface vessels
• The building ways and dry docks during the WWII surge of submarines, destroyer escorts, and landing craft
• Yard shops where insulated components, valves, and pumps were rebuilt
• Berths where boats sat through long refit availabilities

In a compartment where two men could barely pass each other, nobody was far from the insulation work. There was no upwind.

Submarine Work and Enclosed Spaces

After World War II Mare Island became a submarine yard almost exclusively. Apart from a few submarine tenders, it stopped building surface ships. Of the more than 500 vessels built there across its history, 44 were submarines, and those boats are where most of the yard's asbestos exposure happened.

The nuclear era started in 1955, when Mare Island was awarded the contract for Sargo, the first nuclear submarine laid down at a Pacific base. Fifteen years later USS Drum went down the ways in 1970, the last nuclear submarine ever built in California. In 1972 the Navy stopped new nuclear construction at the yard altogether.

What happened next is the part that matters most for exposure. The yard did not wind down after 1972. It spent its final 24 years overhauling and refueling nuclear submarines that other yards had built, right up until it closed in 1996.

Overhaul is harder on a worker than construction. Building a boat means installing new insulation. Overhauling one means stripping out insulation that has been baking against hot machinery for fifteen or twenty years, scraping it off, and hauling it out through a hatch. The Navy's own environmental records for the site list asbestos among the wastes the yard generated and name nuclear submarine overhauling as one of the activities that produced them.

That combination is what sets Mare Island apart from the other yards on this site. The exposure was more concentrated, because a submarine has less air in it than any other vessel. And it ran later, because overhaul work continued for a quarter century after the last boat was built.

Who May Have Been Exposed

Around 46,000 people worked the yard at its wartime peak, and submarine work carried on for five more decades after that. Those most exposed included:

• Insulators working inside hulls where dust had nowhere to disperse
• Pipefitters and steamfitters and boilermakers fitting machinery in confined compartments
• Machinists, electricians, and welders sharing those same spaces
• Submarine crews aboard during construction, trials, and refits

Vallejo families exposed through dust carried home on work clothes are part of the yard's pattern as well.

Illnesses Linked to the Exposure

The confined-space character of submarine work is reflected in the diagnoses that have followed: mesothelioma (pleural and peritoneal), asbestos-related lung cancer, and asbestosis, appearing decades after the work itself.

Why This History Can Matter in a Claim

Two things work in a Mare Island claimant's favor. California has some of the most active asbestos litigation in the country, and the yard's materials, suppliers, and working conditions have been established across decades of those cases. A claim today builds on that record.

The second is the calendar. Most naval yards in these cases closed in the 1960s or 70s. Mare Island ran until 1996, so its exposure window reaches decades later than almost anywhere comparable, and the people who worked its final years are entering the latency period now rather than leaving it.

Filing deadlines run from the diagnosis rather than from the original exposure, and they differ by state. Whether any particular situation fits depends on the facts. If you are looking into this for yourself or a family member, our companion directory can connect you with California asbestos lawyers who handle these matters, and you can also see who may qualify for an asbestos claim.

Records That Can Help

Federal civilian personnel records cover the yard's workforce. Navy service records can tie a submariner to specific boats and refit periods. The hull numbers of submarines built or overhauled at Mare Island are well documented, which is unusually helpful here: naming a boat can anchor a work history to particular years without any employment paperwork at all. Vallejo-area union locals kept their own books. Job titles, dates, boats, and shops all help. See records that help support an asbestos claim.

Common Questions

Was submarine work really more dangerous than other shipyard work?

The exposure conditions were among the worst, because the spaces were the smallest. Insulation dust generated inside a pressure hull stayed there, and every trade aboard breathed it regardless of their own task.

I only worked overhauls, not new construction. Does that matter?

Overhaul work is generally the higher-exposure job. Building a submarine means installing insulation. Overhauling one means tearing out old insulation that has been in service for years, in the same confined spaces. Mare Island spent its last 24 years doing exactly that.

The base closed in 1996. Where do the records live now?

Federal civilian employment records moved to national records repositories rather than disappearing with the base, and Navy service records were never held at the yard at all. Closure complicates record-gathering less than people fear.

I worked there in the 1980s and 90s. Is that too recent for asbestos disease?

No. Disease appearing 30 to 50 years after exposure puts the yard's final-decade workforce inside the window right now and for years to come.

Sources

• Naval History and Heritage Command, "Mare Island Naval Shipyard, 1854–1996" — founding date, ship totals, and the yard's role as the West Coast's leading submarine port in its final 25 years.
• "A History of the Submarines Built at Mare Island Naval Shipyard" — the count of submarines built and the Sargo and Halibut nuclear programs.
• GlobalSecurity.org, Mare Island Naval Shipyard site record — the yard's overhaul and refueling mission and the environmental record listing asbestos among wastes generated.

Figures and dates above should be confirmed against the original sources.

Related Pages

About the Author

David Meldofsky is a California-licensed attorney and the founder of Lawsuit Informer, an educational platform focused on helping people understand lawsuits, consumer safety issues, and legal rights related to defective products and toxic exposures.

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Last Updated: September 7, 2026

Educational information only. Not legal advice. No attorney-client relationship is formed.