— — —--- — —-- - — APPROVED FOR PUBLIC RELEASE $8 XV-B File TO I % Fromi L FI Fempelmam Subjaot hsm%is of’ 100 Ten Shot at Trinity ‘ ‘ 4 The lmEardnrelntiveto the 100 ton shot containing fission Frodlacts 1945werealight However adv ntugo WL 6takenor t n -im l r t y of thietestto the finalshotto developa eyatomor rnon tor ng the nextteat Our problenm in thlef’lr t s oti werethree-fol l 1 Vedic l at Trinity on 7 hy ergenoiee cauaed by pre-detonation and rout in construction hazard 2 Men- ‘ the ohemical procedure of dissolving the %mford Slugn and pumping the solution Into tho explosive 3 monitori the area followinflthe explosion and 4 the oloud containing active material Ur Balnbrid-e and Lt Flushtook Itorlng the reaponeibility of alearing the area immediately before the shot 1 Concerning medioel emergencies there wes only OVQ - an accident in whioh Milton Kahn wan run over by a truck trailer Although the truck wheels ran over his entire body and head it WM fortunat that becflu o of the extremely eoft dir no bones were broken And only t%irly auperfioial lacerations of the ahin were euffered Lt J H Allen who had been at Trinity since 25 April 1%5 took aare of the patient end sent him up to this cite for recovery on May 1 i - $“ “1 i “ 2 The radiation hazards relative to the chemicnl procodvrea turned out to be extremely slieht even though the slug” contained LOO gamma ’ curies and ●bout 1000 beta curie The “slugw was transferred by Sugarman s group from a lead oontainev to Bn underground ahamber by meane of e remote S control operation behind a conorete wall The ‘slug” was then di8eolved iIIa nitrio sold solution end the nitric aoid fumes togetherwith the radioactive j xenon and iodine were dieoharged through a seren tube the outlet of which was ●bout 1000 feet from the ohambere The underground ohanlber waa eo well shielded that the radiation intensity in the working area was less thflnone-tenth r per “ i eight hour day Similarly the amount of radioactive eses issuing from the It was found by means Of e ir ohambers built by J@ Watte ohamber wae not hazardou8 ‘ that if no nitrio oxide could be #melt in the alr there WDS no detectable activity personnel were Considerably less thnn toler nce ‘ ‘“’ in the ●ir The expoaureeof all dono exoept for the final day on 6 MAY 1945 when s ples ount g X about ‘ l 2 ourie war taken from the buffered nitric aoid solution Only one person ‘ ’ Sugarman exoeeded the daily doee while taking these smnples and he only reaeived wae pumped up into the approximately 1 times tolerance After the material staok the radiation intensity around the towers was fairlyhigh W Fluchanan ’ who wae ihatalling the detonator probably receiv RbOUt three O four u lY doese due to diffioultloa encountered during the installation Which required him’ ‘ to stay in the vioinlty for ●bout four hours This dosage was not meaaured b was not oonaidored serious bewause he has had no other expomure to radiation 3 Radiation ha ard afier the a oto This too Proved negliglbl@ ’ ‘ $ were made so that no on eXoept the people in the tanka oould ‘“ but rrangeme ●nter the oontamlnated ●rea until lt ms 8urv@Yd by the medicalgroupe Both medioalpersonaoland Andoraon’@group in the tak -r olothedwith covoralla ● APPROVED FOR PUBLIC RELEASE % APPROVED FOR PUBLIC RELEASE booti7z @OTes PP Vmsks hdersonts nlfmu8ed gas masks whllo the medical group used ref3pira eore If t med out that there wms measurable nctivity only withj n a r dlus of about 30 feet around the center or the tower a en here t i5 activ tydid not exceed 1 10 r per 8 hour day In the center of the crater the activity WS about 0 7 r per hour8 Afeasurement o the fine powdery dust around the crat r showed extremely small nmounts of activity gstj n atedto be cinly@ f%w mieroaviaa per handfulof aar h Nevertheleae it was recommended by the medical group th t no one enter the powcl ry zone without booties and everyone was edvi8wl to wear respirators for tilldusty operations The system P ich was used roved quite succe aful and will urxloubtedly be used again for the final shot The only infraction of rules occurred when Mr Oppenheimer entered the potentially contaminated xone immediately after the medical offic rs he took full ras onsibility for his actions Fowever f The cloud arising from the explosion contained approxin ely 90 % of the active material It was obeurved to rise to a hejght of between 13 m d1 000 feet where there was n westerly wind which carried i nt a rate accordingto iubbardls observnt ior-i in the direction of 35 mile m hour carrlzo%o md Tlllnrosa It was still visible four hours lhter at which ‘o l ween time it wtis somewhat south of Roswell Although dilution had occurred the cloud still hung together kt this time It is thought by Hubbard that the at about 9 o cIock in the mor ing resulted in a thermal air currtints starting rn ld dispersion of’the oloud It ia felt that there was very lj tle likelihood of any confamin tion ev r rnaohillc the earth since there has beeq shown to be a diluticn of 10 000 times for every 2 000 feet vertical descent of such cloud9 - It was impossible c1oud wtm not - ‘ ’ “ ’ ‘ ’ ‘ ’ - ’ “ i - APPROVED FOR PUBLIC RELEASE