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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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GREENHOUSETESTS, UITH SPEEIALREFERENCETO CONDITIONSON IA Startitg 5 October,1943, a Prelq surveyof the ditionof the Shot Islandawas aonductedby Dr. Simon Divlskm, LASL. He found tkt the generalpatternof sitieson Engeblwas not much clifferent frm *at had durhg the weeks folhuing the shot on that Island. Within: of groundzen, the most radioactiveregim, there was no tn therewas l mpid decrease in Intensity. Beyond ’750yards t’ was less than 1 mr/hr. At groundsem the readingsrangedf 150 EUD/hr, dependingon the mount of steel left In the tom. By excavat@ successivelayersof soil in an exceptionally, locatiuiabout 1000 feet from groundzero, IYYfound that the of the sofl deoreasedrapidlywith depth. The activityfi t] Inch layerwas less than & of the actitityin the top Inoh.
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Thla survey wan ~elimlnary to a conferenceat Holmes In Las Angeleson waya and meansfor decentaminating the S’ Followlngthis conference,M was decidedthat decontaminai (1) First,remavingend dumping intothe sea all of 1 layer to bury the generally diopersedradioactive Note Since it might a~ear that lmryingthe contamination entirelyeolve the problemh an area whre subsequentexe{ would be necessary,a digressicn ls made tmre to #et forth upon which this mthod of disposalwas baaed. On account of the great penetratingpwer of gama rtq of the radtitionexposureof a mn etsndingin a contaminal due to dintantradioactiveraterial. For the kind of gamzn radiationcoczlngfran distsnces greater that all of the radioactivematerialis subsequentlyl 20 foot diameterhole Is of the exposure is d 10 dug in such a way as to exposethe previouslycoveredrad the man could at most reeetve10 to 2S of tbe radiatim expo he would trove received if the decontsminatlcmby burial had n t been done.
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This theoreticalcalculationit oonservatlve. Under pract expsrieme haa shown that this method of decentarni~tim i effeotivethan the calculatim indicat periodapproduately U Februa= to 15 MMYNI 1949 to supr removalof the radbactive ecrap fmm Engebl Island. He 1 was dedded that no furtherwork wol~d be done in contamh conducteda aoienttfic5nvestigation of the situationwith emphasison the radioaotlvecontentof dust m the Shot Is’ w ordinuy activities cm the islands. By 81 ring up duet by artificialmeans,b was able to obtainsome radioactfvit~. that there was not enough radioactivityin the st to be a healthproblem,and that the prqmsal to vet the eoil duri •~y, to be absolutaly info). In addition, Dr. RAy sups ad the ~~d #XW remrded lecturesfor the Inatmction of oontr tor p@reonnelb radiologicalsafetyprecautims. Dr. Rayts work lo oovered
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1950, with the decontaminationuoik m Engebioompleted, was mde by Dr. Simon Shlaem,starting25 February. The aensitlveonly to gamas. The pemiesible weeklydc presenttime in tlm laboratoryat Los Ahmos la 300 Id the work With the presentwork week t Eniwetok of 54 hours,the fimum &se mt e for centinuous e 10 lbout 5.5 M& per hour. sero was found 1within the 1,000 foot radiusf outerrnoetedges of this hour can be found. No Indicationof the podtiom of tb old tower detectedwith the instruments.Metal scrapwith aotlti m high &a 3.5 MR. per hour can be fovrxl@t outsidet gradedarea, both seawardand alongthe cero Me. Top soil semplesfran the viclnttyof the Iocation for new tower were colleotedand beta activityof this hae measuredto evaluatethe necessityof mistenlng the sc
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la placedabout l“ abovethe mii spread-toabout 1/4 astitity. Though this cannotbe evaluatedin l preci it would oeernthat mi.steningtk soil WUM be desir This excerptincludesall of the Informationrelativeb c on the islandof Engebithat is oontainedin Ma report.P 22 March 1950, cmtaim all Of the informationCOXlt&inedi relativeto wurking conditionson the island& Jhgebi. sensitiveonly to gaxnas. The permissiblewwkly dos presenttim in the laboratorylt Los Alamo ia 300 m roentgens (M2,) per week. exposure ia about The entire graded was fourd to have With the presentwork week rmcimm dose rate for mnti area within the l,CX)O foot rdius f en activitybelow 1 XR. per hour So No tidicattonof the positionof the old touer base e detested with the imtrumsnts. The %laer~s report of 1 March 19fl ka been rmmved to the lsg~ The grading operationson this islmd have been a-t * :
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As of this date, 3/22/50,all ielmis of Eniuetmkltol free of rmiiatlonhazard,with the lxceptim of the to Runit. T ~’area will be elimhated, as l radiationh gradingwhich ehould be ucmpletedwithin one mnth. At premmt, film badges are being mm by all Holmes& on Enlwetokatoll and sme Amy personnel on IMuetok m the Havy pereonnelon Parry Island. A total of bbo These film badges from the shove it are designedto detest ionizingradi Ie shown thct no radtitim hasard u Eberlru and Runit. At pesent, the film badge tiduetr at fill peak h omler to supplythe demand for essenti tests here. The productim of this mnber seriousprobl= of supply, It appearethat $** fi mm 00 Mny film badges tira radtit ion hazaxd exietso . The processing of thie large numberof film badgestie lntire film badge processing deprtment lt LOO Alamoe Furthermore,, the wear5ng of film badges presentsan psychologicalreactim in the mrkers, who ammo s exist in the ~esence of theao protectivemeaaureso :- discontinuedinmdlately by all personnelexce> tho mind, be well
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Runlt, and that these be disccmttinued l soon l gmdi on this ialendare completed. A few monthslater, after all decontaminationoperation } Since tbio was the final survey,the completereport (sW Officer was assigned to the to be entirely unnecessa~g