Document MM22kwVo4O9pdXQgLwD575Dx

METHODS OF DISPOSING OF SI JXE TOM :HADFD jASOnl ,VE oTORAGc TANKfa The fi.-sr "ase of lead intoxication, as a result of work vithir. a leaded ; r.e atcr&ge tank, occurred in 191i<- At that time, the aource of lead va* thought r.e the sludge Ir. the bottom of the tank and this assumption proved to be correct, erefore, it became necessary that the sludge be disposed of by a metnod which would .:i harmful effect.-, both from axin confer, or inhalation of its vapors after removal os the tank. The immediate,, solution va* the burial method of disposal. This procedure required the necesaary space, tne digging of pita and verlng tne partially filled pita vith soil. The method was accepted without estion until relatively recently. Vitnin me past several years, inquiries nave on .aade by & number cf .;>i 1 companies as a in*. for an alternate method of sludge 3:-: sal. The requirement f-.-r an alternate method arose primarily in those refineries i. r. found that the space available for silage pits was being exhausted. The diffiewi ; ..-.creased because we naa no anew ..edge of vnen the sludge mignt become innocuous, so p * 'he area cdu.d v-e .tea once Haxiu. There have been many aaaumptlona made concern! . - rice factor, tut insufficient supporting data have been available. dome effort na& b-.et made to solve vne problem cf the time required for the ruction of organ^o lead in buried sludge but the effort* -have not been rewarding. principal aifitculty was that every time arrangement* were made for the sampling sludge for it* original lead content, the sample was so low in organic lead content t it v*s not g-.od experimental waterial. It was suggested that ve produce our r, e-: .tee strati on of TEL ir. sludge ir. order to have an adequate sample for study, waver,' there was evidence to show that ended TEL did not behave like "naturally" cur ring TEL Ir. te rae ;.f v. Iappearance of the compound. Added TEL was found to be re rea.il ly vapor-, vet than : hat vr.ic.-i wa* found as a reault of Its accumulation under .' red gasoline. :6.d guessed {.and. '/.ere vus seme evidence to support the conjectme ,0-0 ,'0 S 3ft : ...ft , r jpor* ` .? >.* a ;t r - : ?U> i ; '_? ' tt" . j. * rO-:om "'.t*' ; t i. \e-var. ;`i .h .ug: t and .ixverl.-ttfrtta; r rfc:*'. had ' eer. iwvotei : .vrp-w ratios believed *h*t i t wa ir. s ; i M on tc intola* tc '.3 on a trial experi.-aanoa tire*; -.'.r? ..ecame xneva as i he *atr.eri.r.g Method. It cofiS! sU of ' >.*. ai-dgs 1.: layers ..wt to .eed *nr-e Incites ir. ' rdiituei,*, off ori i sc ;*-Icr. ..! tor orea. co-r* r-rd u y sincLge a.;.5 posting or I 0 'il'Tii 1 t .. /' tt O rt . . ..O ? . . OgO' t . Vi.? . O t :t `.VC 1* .'V 0 . 0-P t i i tY'.-i,"' t y "Ui^s. ' . ; ' ~ , -> :: 1 tor.a c ;;.ro -asr ' >r vee t r,e red sludge has ' ' - it.t . >. . t . . ' . ' / tOy.S-, '.`.cr; - O.. _ t* t P. va V O.. t- P> < * f; . t.-dgi was : renfidnice in the w-nnud hai. - :wr. 0 6 .wan 'c.-i enx.cted wren :mnge cr a sew { , . .rents ),.*ai on u-.a 1 ?. Some Of vr tin ore t.ati .. n to' our vwr. fti-iude toward '0 O ! C?: a. 1 `tit. tO It. t/lti '.vntie f 6 -eg Or - -o Si...ilg '-.ncotlu ft rt-f n o .>aoi ft v?.:, .- , s Oiaco t . ay one tt.jraponent of :U0 -- .CruCiO .. . ra*i .i .eao oo3ipourt-is. Nro other (ta:*rJ ai# r.&ve (ver. t hough otner ccrip'.-n*nts o.ay be :.a ! T.h , .: ft.-reasarv 0, oi.lrix cf o.e danger.-, of 4 he v%p.o-r t. t.tAt arise ftnra .:.:cei" '.w.: oi: te r [ ffv . ar.t sets -t` -ondff io.n> j hAawly, in c 1 .:me v Ia j o SS. T-/i- '."iC r.iu'iU , *.' '.h .'-C>r'' -a'i-"if w* 1 k 00097S i ~r ' e safety _f the method depend on the original dispersion Of organic ~eed fo.rizes and the great dilution Which occur* vfcen it is not in * confined space. Three question* auet be considered in judging the saf*ty of this method of s . ..ige uisposal: - '1 Wr.at are the risk# which arise from the sludge Whan it is spread freehiy 'ith its maximum content of organic lead? ;2; Doe* weathering in reality reduce the organic legd content to a level that makes It completely non-haeardoue end suitable for handling as ordinary waste material? 3! What is the period of time required for reasonable complete vaporization' The risks Involved in handling sludge as it comes from the tank are the same aa the handling of sludge when put Into a pit for burial. There is no reason to be lie v* ''hat any significant absorption of lead has ever occurred as a result of the ordinary proper removal of sludge from tanks. The potential problems that exist are those . r absorption of organic lead through the akin from contact with the sludge and the "r.&iatior. of lead vapors arising from the sludge. Although there are no direct, experimental data to prove or disprove the prooabil:of absorption of organic lead through the skin from contact with sludge, experience maxes it possible to develop certain comparisons. Many observation* have oeen made of men who have work*4 90 tank entry and tank cleaning Jobs. In Bomp inftance 'lefinitely against regulations) men have worked wearing-clothing contaminated yitfo '| ! ' " -v s.odge. .xve worn leather shoes and have had their hands and other skin areas covered |~ th sludge. Although nc determinations were made to measure possible lead absorption, eee workers nave never shown symptoms from this type and degree of exposure. The occasional cases of lead intoxication that have occurred as a result of :r< ;n leaded gasoline storage tanks have always been demonstrated to be the result f absorption 'ey innaiation while within the tank. Therefore, in every case it has rc-r. demonstrated that absorption was a result of either a failure tc ;& proper K 0009762 N V : -'. tone o * ilure of that equipment, ` : `tor, fined skin application of gascli.v; - otretto..? .-.wide rable excess of those fo.u``j n: a?gordinarily in ga6. - ' s. -preoitbie absorption of Ie*4 ha* been found* -.r.g i. of : oc samples c f sludge taken frost leaded g*sc line * .'V* the wear. organic read content va* found 1 M O.Oiit and 'r*.:-...- f3 .'.Ml** to These samples were largely from unwashed lodge . "'re rr.* suits vnicn vere at a level of O.iOji or great*? and these v.rs;- >; .- no a. - -egarded * exceptional. The maximum allowable concentration i out C. JA 1/ 'weight- Although the care lea* handling of sludge w. - .........itait w.th i '*re definite^ r-.-nt condoned, it is highly unlikely that. <n .. . ;i a.- ' -igre<a f ca;e ar.d cieeulir-ass, significant absorption will occur f-'M s'.ucg* sbefore reduction of its organic 1**4 content. " c iegre* . * :atard M-u t *:ght rroa the inhalation of y*pdfs tricing tf sj-resd s. :dg has ^rcwabiy oeer. confused with the hiadrd pro4uc*.t oy :e r ..t of i is epc.rs in ...or.fi. aed spaces. It requires only * tonishlng.y :c:...e*.crati an* irgaaic Mid ,,,r sludge to produce distinctly dangerous ar - rati.-r.s organic >.sa tn the aiv above it when the sludge and air are eonf; t*4 r.c suflii.*zt tiaie : s *i*,,wd for v>*x>ori*ation to occur. However* an al*pit t0tal*y ifferem sex of r-.v oh# clous xist after sludge is spread in the open. sludge is spread its organic lead content is usually . h: a cooes si rut principally by a cons} i*r#.fcie degree of removal which OepUf|..#t,4^| cr.'x :: e vs *r.e i and tr.e * _udg* is flushed with water from pressure hoses. _ . edge spread there is oppcrtvui ty 'or the concentration of organic deed to .: the ,-v* dying r *x n .i even- os -`ispersion alone provides for sr. icsregf^*' sway Ige m. rf*ce, KJc 00057S3 Theoretically it has been shewn that the concentration of TEL in a volume s*.til air over a solution of TEL in gasoline (3 ml TEL/g*l gasoline) drops off ^pid-Ly. , a period cf i8.4 hours the concentrations of lead in a column of still a:r over this Interface would be i34,000 micrograms per cubic foot at a distance tf . 't. The concentration of lead drcp6 tc 33/300 micrograms per cubic foot at a * - re 1 cf b feet above the surface and to 8,3&Q raicrogr&ms/cu. ft. at a level cf 6 >*t tbove the surface. Application of formula# from which these figures have been ri-'-eti hanot "been applied to vaporization from sludge because of many unknown sc tors.* In practice, it is known that the concentration of TEL in the air i ;Oo- `.he interface of sludge and air is very low even initially. No concentration .. -t * : tog rams per cubic foot has ever been found in the air above freshly spread 1 . Ige. 'here does exist a report of a result of 20 microgriuse per cubic foot (that retained oy others , at a level :;f 1 foot above a spread of sludge reported to f. : - oncer.7 ration cf TEL of 0. ii. Ever, at the concentration of 20 microgram# per cot 1 frx.t above the slucge it can be assured that at normal breathing level f t.; t feet the concentration wouio not exceed s micrograma per cubic foot. There- . re. , x nas assurance that, with ordinary care, there is no hazard to be expected sludge spread for weathering even before any vaporization has taken place. In order to determine the question concerning.the vaporization that take# ;-..ace in practical applications, a field investigation va# conducted where samples of ^;..ige ware tanen from 36 test areas when sludge was first spread for weathering and again ~"t:r!5r figures are stationed not because there is any relationship between the magnitude the concentration# tut to illustrate tne reduction of concentration in relation to l: s -.ar.ee. He" 0009784 -5- -.t, the er.d of ft $C-&.y period. Those experimental spread* ye re made over a censiderari* geographic'distribution as far south as Louisiana and Texas and as far north as New Ycr.< State and New Hampehire. The teste were made during all calendar weather periods* At the end of a 36-day period all of the weathered sludge samples except fo^r wre reduced to s. concentration of organic lead of 0.602$ or lea*. Tyro of these four exception!* were found to contain 0.006$ organic lead and two were found to contain 0.00^$.- In one instance where 0,006$ was found in 30 days, an additional exposure of ll days reduced the organic lead concentration toH?.001. Temperature is the most influential factor in vaporisation but extremely high temperatures are not required. At. freezing temperatures little or no vaporizet{ or. occurs and it is advised that days of freezing temperature be excluded from the 30-dsy weathering requirement. Of the 36weathered samples 6 were reduced to zero $ organic I -? ad. If zero results should be required, additional time over trie 30-day period will rv-tai n this re cult. Tonelusions:- 1. Tne handling of sludge as it is taken from the tank and spread on the ground is no more hazardous than the handling of sludge when it is dumped into a pit. 2< Tne presence of sludge spread over the ground in thin layers creates no hazard if ordinary precautions are taken to avoid contact y^th the sludge and thf vapors arising from it. 3. A. 30-day period of weathering (exclusive of days of freezing temperatures/ . reduces the organic"lead content sufficiently toy all restrictions to be removed and to allow disposal or treatment as any ordinary waste. a . Tnere are advantages in the weathering method over the burial method insofar as finality of the problem is concerned and insofar as avails bid it,7 of more and more disposal sites are concerned. KE" 0009785 Medical .>part: flthvl :r o rs ' *:/:C/rO