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 shipyards or laboratories on the west coat or in Hawaii where they worked on problems presented by the contaminated nontarget vessels. Because no safe and effective methods had yet been developed for removing the known or suspected contamination on the nontarget ships, only a list of precautionary measures could be given to ships' captains. These measures were principally as follows (Reference C.9.185, p. 24):


 * 1. Treat evaporators using starch and boiler compound, cold shocking, or, in the case of vapor compression stills, standard cleaning


 * 2. Sink at sea all radiologically hazardous equipment made from wood and plant fibers, such as lines, fenders, nets, camels, and swabs


 * 3. Prohibit burning, welding, chipping or wire-brushing of saltwater lines or exposed saltwater surfaces except under the supervision of a monitor. Scraping is permitted on surfaces provided they are kept wet at all times.


 * 4. When dropping anchor avoid the dust raised from the outgoing chain, keep the anchor wet, use gloves when handling the anchor and chain, and discard the gloves after use


 * 5. Sink small boats with readings greater than 0.1 R/24 hours


 * 6. Scrub urinals and head troughs with abrasive cleaner or acid solution.

In an effort to determine accurately the contamination level on nontarget ships exposed at Bikini. Commander Western Sea Frontier (ComWestSeaFron) on 30 August ordered Commander 12th Naval District to drydock one of the destroyers from the joint task force at the San Francisco Naval Shipyard. USS Laffey (DD-724) was drydocked and inspected on 5 September under supervision of the JTF 1 Chief Medical Officer. The underwater portion of the hull and portions of the saltwater plumbing were monitored. Shipyard workers in protective clothing and breathing apparatus chipped off samples of rust, paint, and scale. Radiation levels detectable with hand-held instruments were found to be below the accepted tolerance level. Samples were also taken from USS Whiting (AV-14), USS Henrico (APA-45), and USS Mount McKinley (AGC-7). The samples were sent to the University of California's Crocker Radiation Laboratory for further analysis, especially for the presence of alpha emitters. Encouraged by the low readings, the medical officer gave permission for overhaul work on USS Walke (DD-723), USS Batton (DD-722), USS Lowry (DD-770), and Laffey, except that work involving the exterior of the hull below the waterline or the saltwater plumbing had to await the arrival of sufficient monitors. A decontamination center was established for yard employees working on the ships (Reference C.9.185, pp. 28 and 32; Reference C.12.2, pp. 84 and 85).

In late August and early September, however, concern increased in command circles that unless a means could be found to service the underwater hulls and saltwater plumbing of the nontarget vessels, they would eventually be rendered useless.

On 9 September 1946, CJTF 1 sent a letter (Serial 079) to commanding officers of all nontarget ships suspected of being contaminated. His purpose was

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