Document 93mv5Qd2GazzMOX0L388r8qyR

Zti&d In scale frosi tank $01, Gulf Refining Company, Toledo, Ohio* This tank was recently cleaned and then was disreaantled for scrap* Side Scale (Area of 100 aq* ft* or 12 sheet) Analysis Husaber iiOA-59^9 Sample total 8l gm Sample analysed ** 10*0 gm Organic Fb * Q.QOQZg (0.2 mg/ 100 ga) ^ Inorganic Fb 0*38 (880 ta^/lOOgjaa) Bottom Seale (Area cf 10 sq* ft* or 6 sheets) Analysis Ihrasber =* Sample total Sample used Organic Fb Inorganic Pb 255 @KS 10 gss G.Q5 (0*5 rsg/l30 gasjv' 2*2^ (2200 mg/XGOvrasj Samples Heoeivcds 11-14-1*0 Samples Reported* 11-26-40 K H 0022388 cl LOV 9, 1940 Dr. Robert Xhoe. Dear Dr. Kehoe: I am submitting two samples of scale scraped from bottom and side sheets of leaded gasoline storage tank, recently cleaned and then dismantled for scrap by the Gulf Refining Co., Toledo, Ohio. The tank #501 of 55000 bbl .capacity had been used for the storage of leaded gasoline for the past six years ana had not been cleaned during that time. The method of cleaning was as follows. The tank was stripped of gasoline, then all of the remaining water was pumped off. high pressure steam was introduced through the bottom manhole for 84 hours, having the roof manhole open at all times. After the tank 2-a q . cooled, one large roof sheet and two lower side sheets on opposite sides of the tank were removed. Two large pics 5* x 15* x o' deep were dug on each side of the tank, the position being close to the tank where the side sheets had been removed so that the sludge and scale could be flushed directly into the pits. Tor two days, working about seven hours per day, the men standing on the outside flushed the tank with high pressure water, washing the sludge into the pits. The excess water was pumped from the pits through the refinery sewer to tne refinery separator. The third day, the men properly equipped entered the tank and washed down the scale from the roof, side sheets and superstructure and flushed this scale into the cits. The fourth day all remaining scale and sludge was swept from around the base of the steel supports and the angle at the edge of Lhe tank. This was flushed into the pits and again the entire tank was flushed with high pressure water for about an hour. I then made an inspection and found the sides, bottom and especially the seams of the side said bottom sheets free of sludge. The tank was cut down with a torch, first removing the roof sheets. :he sides were cut vertically, that is from top to bottom, through the angle iron continuing across the bottom sheets until uhe cuts met. This left the sides with part of the bottom in six sections and these were then pulled to the ground ^nd later cut into smaller sections six by fifteen feet and the inside surfaces then coated with oil. After these sections 'were on the ground I was able oo make a very close inspection and tnere appeared to be no more scale or sludge in the seams than on the sheets themselves. HE" 0022389 2- - I took a sample, #1 of scale scraped from 'bottom sheets. This was scraped from six different sheets in various locations in the tank and represents the amount of scale possible to secure from an area of approximately one hundred square feet. Sample $2 is from the side sheets. This was taken from twelve sheets, four each of first, second and third ring of the tank in various locations and also represents the amount of scale possible to secure from &n area of approximately one hundred square feet. ______ This tank, I believe was as thoroughly cleaned as is possible with only the use of high pressure water, in pulling the super structure, roof and side sheets down there was very little dust. I have tried to give all of the information that might be needed and anything in addition I will be glad to supply if possible Very truly yours, N. D. Siebenthaler HE 0022390