Dissolving of Twenty Day Metal at Hanford

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Om ton of ir radi ttc C uranium Kith fifteen days coolinr was dissolved from a two ton batch loaded intoa clean dissolver on December 2, 3.9L3. Cal cula hd. amounts of a c t i v i t y evolved here 4000 curie6 of I-Ul and 7400 curies of Xe-133; measured values were higher than this by.a factor of 2 t o 3. Preliminary caicilat ions of %he hazard were ude by the method of 6. G. Sut'ton and attempts made t o check these values reac'ings on fixed and mobile instruments, The meteorological corditions during the actual hours of dissolving aero unstable with tbe nine! veering from a 8outherlg direction a t the start toa northerly direction abollt t?eLC-mop through the run. Elaninsonde readings a t Richland during the run indicated a ahallon surface inversion with an unstable conditloo eloft, It is postulated that much of the dilution occurred above the inversion, Reedings a8 h i g h as 2 x 10.4 uc/l of I-131 and 2000 t o 3000 c/m on portable Geiger counters were obt2.inod nith in a radius of 4to5 miles from the stack, Significant read in p tppcarcd i n the Richland - Pasco - Benton City area about noo of Dec mber 3. ZctiEated maximum concentrations ncre on the d r d e r of 10-' t o 10% uc/l of 1-131, Questionable Doeitive road ii gs were obtalnisd on filters at Spokane on Docembc,- 3 and December 5 , 1919. Aircraft measuremnts mado In the direction of Spokane on December 3, 1949, It l a postulated that the peak closest tothe project mas due t? 1-131 indicated peak act lv it ios in the norning a tR lta vl lle and between Uchland and Considerable deposition occurred particularly Cl039to the stacks, vegetation readings, above the permanent tolerance value of 9 mc/lrs o c c m d over a region extending froffi Tho Dalles, Oregon, t o Spokane, and from Yakima t o the Blue Mountains. uc/meter3/b/uc/l; and on vegetation aa 4 x 1 6 uc/locte@/i~r/uc/l. vegetation docayed t o background wlth an eight Gay half-life. The rate of deposltlon in water was estimated at2x 104 thosc found in iof clean potted plants In the area gave results compsrable t o within the project boundary received th noid irradiation varying Aniuls collected from the region indicated that to 80 times tolerance daily. /

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DISSOLTINC CIF T\?ENTY DAY METAL AT HANFm The Health Instrument Divisions were intemsted pr’imarily In obtaining monitoring reaultr t o m e that no one was overexposed t o the active fumecr, and secondariry in the travel pi-the activity and depoeitlon-on_the_vo~tation, Since it I s almost impossible to write 8uch a report wlthout desigmtlng mad, buildings, tefiskr fsaturos, etc. by their local name, Pi- 1, included In the introduction to the report, I s a map ahorring the location of t h e mre prominent

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llpoa receiving this information, oach group participating etarted more dotafled work directed towards obtaining a8 mudl information a3 possible f r o m the operation and seehg that the hies wen liberated safely, An outline of this planning is blows hoo much of tbo work dono at this time aided considorably fa Inter11th appunt of activity b e h g raleased, good dilution of the fumes before they came to tho gmud in the areas wow required fa avoid gross contamination of fbe buildin- and possible exposure of porsonnel. Crlteria decided upon for mather (1). An h verte dvo rtica l temperature gradient extending from the pound to Be Vera1 bundrad feet above. This otipulation necassitated scbeduYng the FUI ~during nl@t-tLPrb, M it 5s only then that inversion conditions a t Hanford Rorks are fie- (2). b faia, tog, low cloudiness, or other factor which might prevent t h e ab tho upper limit of pormieaible wind w e d . (4). W i n d from a materly or eouthmstorly direction so that the plane would aof be forced to fly in t h e vicinity of such ruggod topogreplic featuros aa 3600

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feet hi& Rattlesnake Nountaia to the south of the area. ( 5 ) . Conditions whereby the bulk of the stack effluent would s t q aloft. A d i l W L h 3 factor of 1500:l was decidad upon as the lowest pennlaaible factor. P review of date from the past several years at t h e liW Neteorology Station showed that during n i @ t hours at this season of the year the "aloft" condition prevailed 76% of t h e time, and that t h e a ! ~coverage averaged 6.7 on a scale of 10. Hourly wind speeds betreen 0300 and 1200 averaged from 4-6 nrph at the 7 f e e t level t o 10-11 Ipph a t the W3G foot Ispel. moderate inversion usually overlies the area a t night, forming near sunset and terminatlng about one-half hour after sunrise, nnd t h e probability of its occurence during any particular 2.4 hour period I s alwwe The prevailing direction m8 northwest, Normally, precipitatiop is infrequent i c d conditions for the dissolution on any particular date dght bo god, the mmtb of November, 1949, was p l a p e d with inclement weather which included two periods of recurrent rtorms d t h attendant wlnd and rain, interspersed by a 1 O - d ~ atagmmt period during which celUnge w re continually low and fog wa8 present on an average of nearly 10 hours each day. 3mn8mSd of the run for o m week. This inclement weather necessitated poetDn the mornbg of December 1, the United S t a t e r Weather Burrrau in a specla1 forecast to thin plant, predicted that the end of the uurrent 8eries of frequent 8tom -8 in siet, and that conditione favorable for the operatior: could be ext3cms aould begin Friday d&t,December 2, If conditions were favorable, Saturdrry ai@%, December 3, The dls8olvor nas than loaded do tbat operaThe Us0 DlvisSon, in charge of the actual dirrsolving, elected t o uae the spare 1-m dissolver in t h e "Tw plant (200 West Area) 80 tbat the "heal" resultiag f r o m the #-.

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we- loaded Intoa clean dissolver on December 1, 19L?, and the jackets dissolved DC +he 12-8 shift on Deccmbcr 2, 1949. t m s uf met& per d g a on tap of ti one ton heel. An estimate of 12-16 hours f o r thc dissolution of one ton nas nude. Tho actual length of the dissolving time The amounts of 1-131 and Xc-133 in the metal after 16 days cooling mre os-dnated a t 6150 end 6370 curies per ton rospectively. loai ~ e ' ~ )r emab in the dissolver aid that there laa 30%increase ovcr the avengo in t h c amounts of fission products in tihe outer portion of the slug, the dissolution of one t o u would liborcto 4000 curies of 1-2.31 and 7900 curlee of Xo-133. chftrged from t h e steck. The rate of disc harp ma ostimctec":from throo evolution curves moarsurod in aol v bg period the Xc-133 reached a meLltimum in 14/2 houre and the 1.131 reachee a indicated a xenon poak at about throe hours end an iodin0 peek at about aewn hours uc/l of lte-u3 and IO uc/l of 1-131 in t h o a t a d on the besir of an a i r flow of These cumca Sndicated that r l t h an eight hour cU.8Extrapolatton of there curves to a 16 hour, diasolrhg (Fig.2) The maximum rate of omission waa estimated a t 0.41. cuTiea/sec These vdwa would mount to about 28 Tho 8tcrt planned for 2000 on Docember 2 a8 a cornpromi80 betwen the Dir *@t and the madnnmr 1-131 act lv iw would occur about 0300, withR total of 12 horn before surup to eliminate most of the activity.

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Extra neather forecasting and observation stations were set up by the Air Pr?.ther sonrice to augment existing stations in order t o obtain sufficient data fa:* !oreccstingthe mvament of the cloud and to correlate th6 ed sting conditions with the nc t iv it y pattern found. Reports of forecasting and obsorvation stations over the Northwest ncre utilized t o got a char picture of the weather for reeks bofore the test. mobile Rawinsonde atat€on and two pilal wiits were mw d into the vicinity & the bnford Project for a mre detailed analysis. The Rawinsonde unit was placed a t Force Base, Oklahoma. An additbnal forecaster vias added t o the staff of tho SpoFlights wore made at different altitudes over the area and the instrument values were plotted against altitude changes. mnts appears I n the soction on equipment and procedures. Aset of curves for the pr-lncipal i not ru - The 11. I. Site Survey Crew m sint crested ln checking upon the hazards encounterod in the nmplw any information that could be obtained upon the sproad o r doposition of activity.A series of calculations based on the work of 0. G. Sutbn arrd others on the dilution of gases in the Lomr a h s p h e r e wore performed (3/ 4, 5 , 6). Tbo basic equatina for them cd l cul ntl ma is: . 7

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%x, Yr E) .. concentration in p or curias/lPotel3 at a point dven ty the coordinates x, y, z on a system Yhcre the origin isat the source and the zdinc - tion is down rrind, n - a pure ndr lying 30tmen 0 and 1. The preciee value is mportod 8s a measura d tbo stability of the ntmoephore. b - t h e height of the stack Sn meters. Value8 of the coefficients Cy, C t and n -re abstracted from papre of Sutton’s aa be uaed than for t o s t a in Porton, England. This is one of the wonk p o M o in such a cdmilation since tho conditions a t Hanfozd are undoubtedly different rrith rowto guatirroee, etc. .Hmover, it me f olt that est bat ions bY this mothod ‘Iould be mluablo in foreseeing hazards and ha l nter pre th g results. Tho codf lcie nt ~w c d in the calculetions for a 2001 stack are given 3x1 Table 1.

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In Figure 3 appear the calculated concentrations from a continuous point source 200' above the p a d at distances up t o 200 miles. maxinun expected along the axis of the cloud if it I s assumed that uniform meteomlogical condition8 and flat terrain are encountered througbout the e n t l r e path of t b e cloud. Two values are given for each diatenct: (1) the coefficient of the the nind speed ia meters/sec, and )t: is concentration In uc/l; and (2) the actual concentration f o r an emiesion ratc of 0.05 curier/eec (close t o the average expected for 14.31) d a wind speed of 11 mph, Them coccentrations are the Figure 4 presonts an estimate of the r l d t h of the cloud a t varioua distances If it b assumed that the wind is ateady b o n e direction. fn t u 8 atbe the cbud w i d t h l a defined 88 tho distance betneun the two points on the extremities that The m x h m activity expected et the ground Is prerented in Figure 5 undor t h e same conditions a8 for the a b concentrations. nteady moderate Inversion canditioa w i t h 0 rind a p e d of 11 mph is given in Figure 6. Tho ground pattern expected for a Fhed instruments w e r e located a t strategic spots where power waa available on the reaervatlon, The location of monitorin& instruments during the run it, d w n In Figure 7. All of the counting rate met ~ r sand moat of the air scrubbers were put out specially for the operation and lrter removed. LTield crem to aarq out the folloring joba were planned: (1). Two men in four wheel d r i v ~equipment wore to attempt to locate tbs point of muimam air macentration ard make traverse8 across the cloud tak lng readings on portable GM counten and mall ecrubbcrr deerignd to pull one' cubic foot o f Jr thmugta ac aut io solution, (2). Three men were to operate a radio tr an rdt th g GM countor, built by the %alaInStrrrment DevozOpment Group, This d t m e intended fo be seat up in a

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alloon to several hundred feet 80 thct traverses of the cloud at the a d s could (3). One man vas to travel from the intersoction of routoa 4S and 2s t o everol miles above Hanford reading detachable chvnbors cverp mile and tdhg smll ( 4 ) . Two men were to travel fro= Pasco to Connell w i t h a recording GM counter nd o 1-u2 Cm a b ecrubbor operated from a mobile generator. Ih order t o keep current with act iv it ios in "tho field during the time of evoluAm, t b 3, I. Emerpncy Plotting Room a t Patrol Headquarters was used. rllomd tbe ue)e of three telephones and was conveniently located to WCIdB, the paid radio atauon, Thus it was poesiblo too btc lh reports from the fi old owe y radio, fn>pI various s m y group3 by telepbono, and ~t9oFOlO@Cddata from 4he apoda l Mitr aet up Iy the Air Forces tolephone. This nlso Umed the sa cit the plotting mom facilities in conditions approximating those of all 8ctUd mergerrcp and ma verg valuable in Oaining iaformetion on techniques. Tbs plotting roam was manned by Healtb fastrumant Personnel from 1900 on U/2

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III. Equipment and Procedures , In pn oral,a brief discussion of the oqulpmnt and proccdures used for a particular reading or aeries of read hgs io lncludud h the section pm sent hg the date. This section of the report is intended t o doscribe thoso I t e m s which w m used genetally throughout tho run and procedures nhich were usod it i the iinaly-h Tho o w change is in the mcdhod of eiso cas used on provlous tests. cation and recording, der roplace the vacuum-tuba G lect rom ter circuit and Brown recordor. capacitor by a collected chargo fro71 tho collcction tuba, into an A. C. voltage which is then amplified, rectif'iod, and measured in ci vacuum-tuba volt ne torc lr - of tho condanser lncludod tho addition of a material q f high insulating betnoon tha plates end electroplating the vibrating dinphram with %-karat mld. lat or for the vibrnting condonsor comprise the vacuum-tuba unit in Adit ion to tho conventional power supply, This monitron Is built nround a modifid vibrating …