Tracing Tracy Territory: Still secrets at Camp Tracy
by Sam Matthews/ TP publisher emeritus
Jan 29, 2010 | 12655 views | 5 5 comments | 25 25 recommendations | email to a friend | print
Despite graffiti and its general dilapidated state, the three-story-building that once served as a prisoner of war interrogation camp outside Byron still offered a tour of 300 onlookers plenty of history a weekend ago.  Sam Matthews/Tracy Press
Despite graffiti and its general dilapidated state, the three-story-building that once served as a prisoner of war interrogation camp outside Byron still offered a tour of 300 onlookers plenty of history a weekend ago. Sam Matthews/Tracy Press
Did interrogators at Byron Hot Springs sometimes use gas masks smeared inside with rancid onions to loosen the tongues of World War II prisoners of war?

That question remains unresolved, but still worth asking, after my visit to Byron Hot Springs on Sunday afternoon.

I was among the more than 300 people who walked through what is left of the venerable spa hotel in a tour and talk that gave people a glimpse of what remains of the ultra-secret prisoner-of-war interrogation center.

The three-story building with full basement, constructed in 1914, has never looked worse in its 96-year history. Although the exterior red brick walls are intact, the interior elements are crumbling, and everything — inside and out — is covered with graffiti.

But regardless of the building’s sad condition, it was still a fascinating place for the visitors to see where Japanese and German prisoners of war were questioned from 1942 to 1945 in an effort to gain valuable wartime intelligence. And valuable information was indeed secured.

As the visitors gathered Sunday in the ground-floor reception area and above around a second-story railing, U.S. Army Maj. Alexander Corbin, author of the recently published book, “The History of Camp Tracy,” spoke.

Corbin stressed that the interrogation techniques used at the base, known as “P.O. Box 651, Tracy, Cal.” or “Camp Tracy,” worked amazingly well to glean valuable information from Japanese POWs. Those techniques included treating the prisoners with respect, putting them at ease, befriending them, feeding them Japanese food prepared by special chefs and using second-generation Nisei interrogators who were fluent in the Japanese language and familiar with cultural issues.

According to Corbin’s book, those techniques contrasted with at least some of the aggressive interrogation techniques, including water-boarding, reportedly used early in the Iraq war at Abu Ghraib in Iraq and Guantanamo Bay, Cuba. That contrast, underscoring the success of Byron Hot Springs methods, is a central theme of Corbin’s book.

After his talk, I asked Corbin about the onion masks, of which I first caught wind in 2001 from an e-mail sent by Willaim Piavis, son of a dentist who was stationed at Byron Hot Springs during the war. Piavis wrote: “I do remember my father telling me one time that they used ‘onion masks’ to gain information from the PWs.”

A year later, when I interviewed Bill Burdette, first sergeant of the Army guard, Bill didn’t bring up the topic — but when I asked about it (to his surprise), he confirmed that onion masks had been used on some POWs while medical personnel stood by, monitoring the pulse and blood pressure of those wearing the masks and laboring to breathe.

Corbin said he had heard the term “onion masks” used vaguely, but he didn’t find any details about their use or confirmation in written interrogation reports. He said his focus in the book was on the interrogation of the Japanese POWs, who comprised the largest number of prisoners at Byron, and not the smaller number of Germans.

If used at all, the onion masks could possibly have been put on the faces of Germans and not Japanese prisoners, he said. And that possibly could be true, although neither the dentist’s son nor Burdette restricted their use to German POWs.

Japanese veterans who had been interrogated at Byron Hot Springs never mentioned onion masks in extensive interviews with Japanese filmmakers who produced an in-depth documentary on the secret base and the valuable information about ships, planes and Japanese homeland targets given up by Japanese POWs.

If Germans were the only targets, then some of the most likely candidates for onion-masks were members of a U-boat crew who were grilled at Camp Tracy about the killing of one crew member they suspected of giving up information to U.S. interrogators at an East Coast base. The U-boat crew was taken to Byron Hot Springs for further, intensive interrogation, which a book about the episode indicated was very aggressive. The U-boat sailors refused to give up any information about the killing, however, and were later executed at Fort Leavenworth, Kan.

The bottom line, for me at least, is that the use of onion masks remains a part of “Camp Tracy” history, whether Corbin included it in his book or not. Perhaps the Army major can learn more about their use, if he pursues the issue in further research. From our brief conversation Sunday, he didn’t seem very anxious to do so. Stay tuned.

• Sam Matthews, Tracy Press publisher emeritus, can be reached at 830-4234 or by e-mail at
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January 31, 2010
I thought Camp Tracy was the state penn east of Tracy! o_o
January 31, 2010
This is about ten to twenty miles north of Tracy, CA. It is closer to Discovery Bay or Brentwood, CA. Leave Tracy, CA in San Joaquin County going north on Byron Road and enter Contra Costa County - Byron, CA.

Here is what I found on,_California#Byron_Hot_Springs

Byron is a census-designated place (CDP) in Contra Costa County, California, United States. The population was 916 at the 2000 census.

Byron, California is also home to the somewhat well-known and historical Byron Hot Springs, a now-abandoned resort which was a retreat that attracted many movie stars and famous athletes in the early 1900s. The first hotel was built in 1889 and was a three-story wood building, with a few cottages scattered nearby, as well as a laundry, gas plant and ice plant, all of which were destroyed by fire on July 25, 1901. A second hotel, also three stories, but made of stucco was constructed 1901-1902, but it burned on July 18, 1912. The third and final hotel, a four-story brick structure was built in 1913 and still stands.

January 31, 2010
governmentbuzzword, you can google map or mapquest byron hot springs road and then click on the satellite view. If you look at the map look where Byron Hot Springs Road comes off of Byron Highway look down where a road goes off to the left and circles around the brick building and that is it.

So basically you can take Byron Highway and take a left on Byron Hot Springs Road (near the Byron Inn Restaraunt). Then take your second right. I donot know the street name. Follow down to the site.
January 30, 2010
Sam, I was waiting for you to comment about this. I wish I would have gone on the tour. I am a huge fan of BHS. I have been there many times without a guide and lucky enough to see the victorian house before it burned down. Seems like most of the taging is recent, with in the last year or so. also, If I am remembering right, I think u-boat people who were executed were actually executed after the war was over, which is interesting and kind of wrong. I am really upset to miss this.
January 30, 2010

Isn't Byron in a different county than Tracy, CA? Where is this place located in Byron, CA? I never heard of Byron Hot Springs before.

Thanks for letting us know the history, but please let us know where it is in relation to Tracy, CA.

If they cleaned it up it might have been nice tour for one of my thesis papers in college. Is this out past Mountain House, CA where they have San Joaquin Delta College?

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