Citation: OPERATION CROSSROADS, RADIOLOGICAL DECONTAMINATION OF TARGET AND NON- TARGET VESSELS Part 2 pp. 20-21
4th Report
18 September 1946
INVESTIGATION OF RADIOACTIVITY Of Vessels from Bikini At the San Francisco Naval Shipyard
Begun on 5 September 1946
Yesterday morning aboard the LAFFEY one experiment in decontaminating salt water piping was concluded and another begun. The experiment just concluded awaits laboratory testing before any results are known.
The section of Firemain which had been pumped full of pH 6.0 solution (Acetic Acid and Ammonium Hydroxide) on Saturday, 14 September at 1100, was blown out at 1100 yesterday. An air hose was attached to one end of the Firemain and a hose led from the other end to a steel barrel up on the main deck, and the Firemain was blown clear. The contents of the barrel were monitored and showed radioactive emission as heavy as had previously been found in the Firemain on Saturday (.010) which would appear to indicate that the decontaminating solution had brought a considerable portion of the radioactive particles out with it. The barrel of radioactive solution was hoisted overboard, using a quaywall crane, onto a truck and when taken to the Industrial laboratory to be held there until arrangements are made for disposal. One quart of the solution was taken by Dr. Scott for a laboratory assay. After the Firemain had been blown clear of the solution, the air service was disconnected and a fresh water hose connected to the Firemain. The hose at the outlet end was led to a second barrel for examination of the first amount of flushing water. This water was found to be practically free of emission, so on the advice of Dr. Scott the discharge hose was led into the bay and flushing operations were scheduled to continue overnight. The flushing operation was begun at 1330. The leading man of X-56 who was holding the hose in the barrel when the radioactive solution was being blown from the firemain received spray and some of the liquid on his bare hands. He was advised to wash it off immediately.
The second shipboard experiment in decontamination of copper nickel salt water piping was begun yesterday after the necessary preparations by shop 56 had been completed. A section of approximately 50 feet had been blanked off and furnished with hose connections on each end. A reservoir in the form of a 50 gallon drum (steel barrel) was set up and filled with a 1.08% normal solution of Hydrochloric Acid. The acid was pulled from the reservoir thru a reciprocating air pump
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to the blanked off section of Firemain (which had been flushed with fresh water for 30 minutes previously). The acid circulating operation was started at 1030. The outlet from the lower end of the Firemain was led into the reservoir drum. About 35 gallons was required to fill the main. Within a matter of minutes the drum solution began to show radioactive emission. At the end of the first hour a sample from the barrel was taken by Mr. Gordon, the yard chemist, and checked for acid content. Every two hours thereafter the solution was so checked. At 1830 the acid content had levelled off to about .46% normal and it was decided to stop this stage. At 1915 the acid circulation was stopped. Air was used to clear the Firemain of acid, all acid being led into the acid barrel. This showed considerable radioactivity. At 2050 flushing operations with fresh water were started. The first barrel of water received in flushing was too active and had to be saved for disposal at sea. The second barrel of flushing water was declared by the monitor, Dr. Chadbourn, to be safe for dumping into the bay. The discharge hose was then led overboard to the Bay. The flushing was begun at 2050, and completed at H200, at which time air was blown thru the main. At 2210, the second acid circulating phase began. The acid was of a 0.88 concentration.
The day aboard the HENRICO was spent in blanking off the flushing system piping {galvanized steel), setting up pumps, mixing tank etc., for the third and fourth piping experiments (using pH 6.0 solution and Hydrochloric Acid solution in sections of steel piping).
In the afternoon an inspection party including Admiral Solberg, Captain Maxwell and Captain Lemler boarded the LAFFEY and was shown the work in progress. Information was given and received, and will be the subject of a separate report.
EGS
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Source: OPERATION CROSSROADS. RADIOLOGICAL DECONTAMINATION OF TARGET AND NON-TARGET VESSELS. VOLUME 2 , DNA ltr, 21 Apr 1982, THIS PAGE IS UNCLASSIFIED, DIRECTOR OF SHIPTECHNICAL INSPECTION REPORT. Radiological Decontamination of Target and Non-Target Vessels, VOLUME 2 OF 3.