Document M4MOqGLnQGDjReG3Jjx0qKzZ9

REPORT on f ' Methods for the Purification of Water after Its Transportation and Storage inCans, Drums, and Tanks That have been Employed as Containers for Leaded Gasoline Prom The Kettering Laboratory of Applied Physiology, College of Medicine, University of .Cincinnati, Cincinnati, Ohio N5320 TABLE OP CONTENTS Page Number Abstract i I . Purpose ...... ......... ..................... 1 I I . Conclusions ................... ........ .. .. 1 III. Procedure ........... .......... ............ 1 A. Removal of Gasoline Odor and Lead from Drinking Water ..... ................... 1 . Tests with powdered carbon ....... I B. Cleaning and Field Studies ............ I 1 . Five-gallon tin cans' ........ ...... 2 . Fifty-gallon drums ................ 5 5 . Gasoline tank-trucks. .............. I).. Gasoline tank-cars ...... . 2 k 5 5 7 9 12 IV. Recommendations .......... .................. 12 A. Five-gallon tin cans ................... 12 B. Fifty-gallon gasoline drums ........... C. Gasoline tank-trucks ................... 13 14 D. Gasoline tank-cars .................... Tabulated Data 15 Table 1 - Relative Effectiveness of a Number . of Materials in Removing Inorganic Lead, Organic Lead, and Gasoline Odor from Drinking Water .......... 18 Table 2 - Removal of Inorganic Lead, Organic Lead, and Gasoline Odor from Water , by Granular Carbon Filter Bed 1|2 " D by 2 * Deep ....................... Table 3 " Removal of Lead and Gasoline Odor from Water by 15" x 6" Granular Hydrodarco Bed in Filter Case .... 19 20 Table lj. - Lead Content ana Gasoline Odor of Water Stored in 50-Gallon Drums, Following Treatment with 1 Pound of Powdered Activated Carbon ...... 21 Table of Contents continued Page I,umber Table 5 " Lead Content of YYater Following Prolonged Storage in 1 Gallon Tin Cans .................... Table 6 - Lead, Zinc, and Gasoline Odor in Water after Prolonged Storage in' 50-Gallon Gasoline Drums ....... 22 23 Table 7 " Lead Content and Odor of water Transported and Stored in Gasoline Tank Trucks ........................ Table 8 - Lead Content and Odor of water Transported and Stored in Gasoline Tank Trucks .................. 2lj. 25 Table 9 " Lead Content and Odor of Water Transported and Stored in Gasoline Tank Trucks ...................... Table 10- Lead Content and Odor of Water . Transported and Stored in Gasoline * Tank Trucks ......... . ............ Table 11- Lead Content and Odor of Water Transported and Stored in Gasoline Tank Trucks ....... Table 12- Performance of Wallace and Tiernan Portable WaterPurification Unit .. 26 27 * 28 29 Table 13- Lead and Gasoline Odor of Water Stored in Gasoline Tank Cars .......... JO Drawing ' Details of Steel Water Filter ............... 3^ i -i~ ABSTRACT Methods for the Purification of Water After Its Transportation and Storage in-Cans, Drums, and Tanks That have been Employed as Containers for Leaded Gasoline Satisfactory means were sought for freeing drinking water of lead, odors of gasoline, and objectionable color, that might be picked up from the use, in emergency, of various types of containers that had been employed previously for the trans portation and storage of leaded gasoline. Methods for cleaning such containers, prior to the introduction of water, were also studied, and the degree of contamination of water stored in the cleaned containers was determined. From the results of these observations, certain facts and principles can be stated as the bases of recommendations for cleaning gasoline containers and for treating water that has been stored therein, . ... 1 . Activated carbon is superior to other absorbents for the removal of color, odor, and inorganic lead, and is almost as effective as any other In removing organic lead. It can be used in the granular state in filter beds or added directly to the water in the powdered form and then filtered out by any available sand filter, or strained out of small quantities of water b y flannel cloth, 2 . 5-Gallori tin cans can be cleaned effectively by a thorough rinse with soap and water, followed by several rinses with clear water. Water stored in these cans does not pick up dangerous quantities,of lead, but should be used promptly to avoid the development of color and sediment In the form of rust. -ii 3. 50 -Gallon drums can be prepared for use most satisfactorily, by being steamed for JO minutes and then thor oughly rinsed with water to which a little powdered carbon has been added. Water stored in drums for o days shows but little progressive increase in lead content, but it soon develops a lead concentration that may be somewhat above 0. 10 p.p.m., when introduced into drums that are coated with scale on their interior surfaces. The lead concentration of such contaminated water may be reduced to safe levels by adding l/ 2 lb. to 1 lb, of powdered activated carbon to the contents of each drum, mixing the contents thoroughly by rolling or otherwise, and straining through a flannel cloth or sand filter. Zinc, present as a white sediment, can be removed in the same manner. -1. Ii, Gasoline tank-trucks should be steamed for at least 90 minutes and thoroughly flushed with water to remove loose scale. After I4.O hours* storage in tanks so treated, water rarely contains more than 0,15 lead, and this, together with the increased color and sediment caused by prolonged storage, can be removed by filtration through mobile or portable sand filters. Added assurance as to the potability of the water may be provided by adding 1/ 2 gram of powdered activated carbon for each gallon of water and filtering through sand* As mucli as 0 ,1|.0 p.p.m. of lead, together with well defined gasoline odors, can be removed in this manner. 5 . Gasoline tank-cars should be steamed for at least 6 hours. Loose scale and sludge should be removed by flushing with a pressure hose before the tank-car is filled with water. The possibilities for the contamination of water that is trans- -ill ported in this type of container do not differ materially from those arising from the use of tank-trucks, and therefore, the same procedures and precautions are required. 6. Water transported or stored in the above containers is not exempt from the usual requirements as to chlorination. -1- I. Purpose The purpose of this study was to determine what opera tions are necessary to ensure the potability of drinking water when emergencies require the use of containers previously used for leaded gasoline. The containers considered were: 5 gallon cans, 50 gallon drums, tank-trucks, ana tank-cars. II. Conclusions M '` With the use of proper cleaning methods (see recommen dations below) containers previously in leaded gasoline service may be used to store and transport drinking water, but such water may have to be chlorinated to ensure its potability. V/ater stored for any length of time in iron tanks acquires some color and sedi ment, but these along v/ith a slight odor and small quantities of lead may be removed by filtration through the mobile or portable Army purification units. Gasoline odors and l e a d appreciably above permissible limits in drinking water can be removed satis factorily, when necessary, by filtration through granular acti vated carbon beds or by treatment with powdered activated carbon. This treatment, however, will rarely be necessary if the contain ers have been properly cleaned ana if storage of water in the containers does not extend beyond lj.0 hours. i III. Procedure The study was divided into two parts: (A ) Laboratory studies to determine the best means of removing lead and gasoline odor when present in drinking water, and (B) methods for cleaning the containers and field studies with containers so cleaned. y -2- A. Removal of Gasoline Odor and Lead from Drinking Water A number of materials were Investigated to determine the most efficient means of removing gasoline odor and lead when !' present. Table 1 lists the results obtained with various absorb I. ' ent or ion-exchange materials. In these tests, onje gram of each material was shaken for 1 hour with a sample of each of the prepared solutions containing known quantities of inorganic lead (as lead nitrate), organic lead (as triethyl le;ad bromide), or gasoline of a known threshold odor value, all samples being of equal volume. After shaking for 1 hour, the absorbent was removed b y filtration and the filtrate was analyzed to determine how much of the impurity was still present. Analyses were made for total lead, any organic lead present being converted to the inorganic form by addition of bromine water. The standard dithizone method for lead determina tion developed in this laboritory was employed. (Bambach and Burkey, Ind, Eng. Chern., Anal. Ed. lL, 90l{. (191+2 )) In testing for threshold odor (T.O.) values the standard method of diluting the sample with odor-free water was employed. Thus the T.O. value, whenever recorded, gives the dilution with odor-free water required to reduce the odor cf the sample (in the cold) until it is barely perceptible. Changes of pH over the range Ip-8 had no appreciable effect on the ability of the various materials to remove the undesirable contaminants. Prora. Table 1 it may be seen that organic lead is the contaminant most difficult to remove. It may also be seen that the choice of absorbent is limited to three -- activated carbon, Amberlite lR-100, and Zeo Karb. The pro ~3 nounced superiority of activated carbon for the removal of odor and inorganic lead (as well as color) and the fact that it is practically on a par with the other absorbents in the removal of organic lead, indicate that this absorbent used alone would be ' satisfactory for the removal of all the harmful compounds involved in this study. ' The next step was to determine the efficiency of granu lar activated carbon beds in removing the contaminants when pres ent individually or in combination. For purposes of individual study, high concentrations were purposely chosen in order to cover the worst conditions that might occur. The activated carbon used was "granular Hydrodarco." A glass tube of 1" I.D. containing * 1- 2 inches of sand was covered with Hydrodarco to a depth of ' 20~2k inches. After flushing away loose particles of carbon, the test waters were passed through the columns at a rate of 50 ml. per minute, which corresponds to a rate of 2, 5 gallons per minute for a filter bed of 1 square foot area -- the rate recommended for the most efficient operation of carbon beds, Channeling was avoided by employing a feeding arrangement which kept the beds completely covered with water at a constant head. The standard I42" sand filter of the Army mobile purification unit, when replaced by granular activated carbon, v/ould give an effluent of 25 gallons per minute, at the same rate of filtration, but this rate could be increased considerably with clear waters only mildly contaminated by lead and gasoline. Table 2 gives the capacity of such carbon beds for various types and degrees of contamination, ; Again the limiting factor proved to be organic lead. However, when this was present,:: in moderate amounts, as in run f/ii -hr- (Table 2 ), the limiting factor was gasoline, odor. Although the runs were terminated as soon as the odor of gasoline became ' definitely perceptible, the Capacity to remove moderate amounts of lead had not been reached since the water at the end of the run had a total lead content of only 0. 01 p.p.m. Therefore, when water is only moderately contaminated by gasoline odor and lead, the life of the carbon filter bed may be expected to be several times 30,000 gallons of water. Preliminary work indicated that either powdered or activated carbon could be used. ,vVith granular carbon, a special filter case must be used for treating small quantities of water. Such a case was designed and used to study contaminated water stored in gasoline drums (Figure 1 ). Powdered charcoal could also be added directly to the water and the carbon"could be filtered off through a flannel cloth or permitted to settle out. The results of tests with the filter case and various ..types of lead and gasoline contaminations are given in Table 3 * 1 . Tests with Powdered Carbon In these tests, drums which had previously contained gasoline (Sohio X-J0 ) were allowed to drain and air spontaneously. They were then filled with water to which gasoline (to give water with T.0 . value of 10-20) and lead (0. 15 p.p.m. inorganic and 0,15 p.p.m. organic) had been added. One pound of powdered carbon was added to each drum and the drums were shaken for 30 minutes. The contents of one drum were tested by withdrawing samples every 30 minutes over a period of 2 hours, after which the drum was allowed to stand for 1 week, samples being withdrawn at various intervals. The water in the other drum was sampled -5- end of 2k hours. The results are given in Table k* In every sample taken during the 30-minute period, gasoline odor was absent from the filtered water, while the lead level was approx imately 0, 02 p.p.m, After standing 2k hours, there was a slight but insignificant pick-up in gasoline odor, but no increase in the lead content. These laboratory tests proved, therefore, that the con taminations resulting from the storage of gasoline in containers previously used for gasoline could be effectively removed either by using carbon filter beds or by adding powdered carbon directly to the Y/ater. *. B. Cleaning and Field Studies In order to make satisfactory reeommendationsTor clean ing procedures, it was necessary to establish the degree of con tamination of water which could occur In the field and to deter mine the precise steps which must bs taken to render it safe or to reduce the contamination to levels susceptible to effective handling by the methods described in the previous section. All the types of containers that might be used for the storage of water were studied, 1 . Five-Gallon Tin Cans Two cans were filled, one with aviation gasoline, the other with an ordinary grade of leaded fuel (Sohio X-70); they - were then emptied, drained, and allowed to air. After sufficient time had elapsed (30 minutes) they were half filled with water, 1 oz. of ordinary powdered soap was added and the can was shaken vigorously for 3 minutes. The soapy water was discarded and the can was rinsed with clear water, filled to overflowing, emptied, and filled again with tap water. The following results were obtained. Can #1 - Aviation fuel Can -jfU- - Sohio X-70 0, 003 p.pm. Pb after 2J4. hr, 0,065 p*Pm. Pb after 1 week No odor O.OO3 p.p.m. Pb after 2 hr. 0, 110 p.p.m. Pb after 1 week Very faint odor Other methods of cleaning, such as draining and spon taneous airing, followed by rinsing several times with water, or by simple filling with water to displace vapors and droplets of gasoline, gave waters which showed a lead content no higher than those given above, but the gasoline odors were decidedly heavier. An additional series of observations was carried out to determine the extent of lead contamination that occurs when water is stored in tin cans.for an extended period of time. Various types of water were examined In this respect. The re sults are listed In Table 5 * After 1 week there was a decided pick-up In rusty sediment and color, especially with the chlor inated samples, but the increase in the lead content was insig nificant and decidedly less than that observed in the case of the cans employed in the cleaning tests. This result was surprising since the cans used in this second experiment were said to have been soldered with a lead-containing solder, and one expected to find an increased lead content in water stored in them for a con siderable period.. The work was checked, therefore, with 5 fresh cans, with results that agreed substantially with the findings listed in Table 5 * As it is hardly likely that water will be kept in such small containers for more than a few days, these observations demonstrate that ^ ' ^ l l o n tin cans can safely be used to transport drinking water. 7- 2 . 5Q-'G'allon Drums Two additional problems presented themselves in respect to this type of container. Since these drums are usually made of galvanized material, there was the possibility of an additional hazard from zinc, and the zinc content of the stored water was determined. Some drums are also known to be coated on the inside with scale and it seemed possible that this scale might increase the lead content of the water if storage periods were prolonged, A number of methods for cleaning drums were investi gated. In the case of a first series of six drums, all of the gasoline was permitted to drain out and the drums were allowed to air spontaneously for some time. They were then half filled with water, 1 l b . of soap powder was added to each, and the drums were rolled back and forth over a distance of 20-J0 feet for about 15 minutes. The soapy water was discarded and each drum was rinsed with 20 gallons of clear tap water, the rolling treatment being repeated. The drums were then filled to overflowing to displace any remaining droplets of oil or gasoline, and. were again emptied. Only one of these drums had a definitely scaly interior. Two drums (Nos. 7 anci 8 ), containing no visible' scale, were cleaned by the procedure described above, with the' following modifications: After the gasoline had been drained out, the drums were aerated for 15 minutes with an air hose, and in the washing process l/ 2 lb. of powdered activated carbon was added to the rinse water. . One drum with interior scale (No. 9) was treated merely by steaming for one hour. : .. -8- After being cleaned by one of the foregoing methods, all drums were filled with fresh tap water and stored for 8 days. Samples were withdrawn for analysis at the end of 1, 2 , if., and 3 days. The results are given in Table 6. As may be seen, there was only slight evidence of lead contamination in the water stored in drums with clean bright inner surfaces, and no significant evidence of progressive increase in lead content during prolonged storage in such drums. Water in the drum with the scaly interior, while showing no progressive increase in lead content over the 3-day period, in one case was contaminated promptly with lead to a point slightly above the permissible limit of 0,10 p.p.m., in contrast to an average of about 0.03 p.p.m. for the drums with '. bright interiors. The gasoline odor in the first 6 drums was sufficiently noticeable to make the taste of the water objection able (average T.O. value, 25) On the other hand, the water in drums 7 and 8, while entirely free from gasoline odor, possessed a musty unidentified odor which was as objectionable as the gaso line odor. Water from drum 9 was the best since it was practi cally free from odor (gasoline or musty)> until it had been in storage for four days, after which a fleeting gasoline odor was detected. The zinc content of the water stored.in all the drums listed in Table 6 gradually rose as the length of the storage period increased. (The apparent decreases recorded undoubtedly arose from the fact that the sample drawn was not representative because of settling of the zinc deposits.) In no case, however, was the quantity above 10 p.p.m.' host of the zinc was present as a white sediment and tests showed that almost 95^ could be removed by filtration, particularly when the water was cloudy. Several -en folds of flannel cloth made a satisfactory filter. 3. Gasoline Tank-trucks The results of observations made on a number of gasoline tank-trucks are shown In Tables 7~ H The tables are self explanatory and definite conclusions can be drawn from the results. It can be seen that water stored in steamed compartments for IS hours is safe insofar as lead content is concerned. In the dirtier tanks there was a slight increase in lead content as storage was prolonged but water in well steamed compartments did not contain more than 0. 15 p.p.m. at the end of I4.O hours. Gaso line odors were faint and while distinct in waters stored in .' closed containers these odors could barely be noticed when the vessels were kept open to the air. Therefore -, if clear water collected In cleaned tank-trucks is used within the first !{. hours of storage, no treatment other than chlorination will be required. Following storage for l8 hours or longer, there was a distinct increase in sediment and color, but both were easily removed in a laboratory test simply by filtering through a sand filter. This operation reduced the odor as well, and, when moderate amounts of lead were present, it lowered the concentration to a safe level. Water that had been stored in an Army truck (#80l|.B2 - two 375-Sallon compartments) under various conditions, was filtered through sand by means of a Wallace and Tiernan portable purifica tion unit. The results are listed in Table 12. The unit effect ively clarified the water, without coagulation procedures, when the rate of filtration was approximately 5 gallons per minute. Moderate concentrations of lead were also removed. Tests carried M -10- out with water contaminated by lead and having a gasoline odor of the approximate strength observed after lj.0 hours' storage of water in steamed and cleaned compartments, proved that the lead content of the effluent could be reduced to a safe level even when ^000 gallons were passed through the unit without backwashing (Runs 1--Ip, Table 12), The lead concentration in the water did not vary from the beginning to the end of the run and averaged approxi mately O.O65 p.p.m., this fact suggesting that the organic lead may not have been removed (See Table 1 ), Some confirmation of this possibility is offered, perhaps, by the results in Run 6, in which inorganic lead was the only contaminant. In this instance the lead content of the effluent filtered water was only one-half that obtained in Runs 1--Ip and Run 8 . The results of Run 5 show that after the unit has been employed to filter water contaminated by lead and gasoline, and after backwashing has been done in the customary manner, it may be used to filter "lead-free" 'water without danger of imparting significant quantities of lead to the water. The data of Run 8 show that lead removal is not altered appreciably-by change in the pH value of the water and confirm the results obtained in Runs 1--Ip, Although it is not likely that water stored for ipO hours in properly cleaned tanks will contain lead in excess of 0.15 p.p.m., a test was made with a badly contaminated water (Run 7 )* In this test, 25O grams of powdered activated carbon were added to each 575 gallons of contaminated water and after thorough mixing (the truck was driven for about 10 miles) and a quiet settling period (2 hours), the water was passed through the unit. Lead and odors were absorbed by the carbon, and the effluent filtered water was odor-free (except for chlorine), and -11 safe insofar as its lead, content was concerned. It is apparent, in fact, that the addition of carbon offers an added assurance that the final water will be safe for use, since it not only removes all of the odor and inorganic lead but is also a more efficient agent than sand for the removal of small quantities of organic lead. The powdered carbon may be added to the water . immediately after the tanks have been filled and the only mixing required Is that which occurs automatically while the truck Is driven to its destination,, The effectiveness of the treatment with carbon is not impaired by moderate turbidity of the viater, kVith the amount of carbon employed in Run 7* it was found that there was no clogging of the sand filter during a run of 750 gallons, and it is likely that the number of backwashings of the filter required will not be appreciably greater with carbon than is usually necessary when coagulation is employed, ' In connection with the removal of gasoline odor, It was noticed that a very fleeting odor was obtained occasionally, par ticularly when the filtration rate was too rapid and when carbon had not been added to the water. In every case, however, the odor disappeared after only a few minutes* exposure of the water to the air, while in most Instances the only odor in the effluent water was due to the chlorine added by the chlorinator. Repeated use of the steamed compartments can be expected to improve the quality of the water, particularly insofar as odor is concerned. Tests on the tank-truck also revealed other things, as for example, the necessity of flushing away loose rust and scale before each filling with water, particularly if the water had remained in the tank for more than a day. They also showed that the water employed to displace gasoline droplets on the water surface need not be entirely discarded, if the tanks are filled to overflowing, and that the compartments may be filled immed iately after cleaning, . Lj_ Gasoline Tank-cars Two tank-cars which had been in continual leaded gasoline service were studied (Table 13). They contained only small amounts of scale. If a man (provided with a canister mask or an air-line hose mask), enters the steamed tank he can flush away most of the loose scale by means of a fire hose, bater stored in such tanks appears to be perfectly safe insofar as lead content, odor, or color are concerned if used v/ithin 2lu hours. Steaming beyond six houhs is not necessary. Waters having low pH values tend to pick up small quantities of lead and color, but not to a dangerous extent. ' IV. Recommendations The following'recommendations are made for cleaning containers previously employed in leaded gasoline service, and for handling the.water stored therein. , A. 5-Gallon Tin Cans 1 . Choose new cans with bright interiors. 2 . Allow the can to drain for 10- 15 minutes in order to remove as much gasoline as possible. 3. Pill the can with water until half full, add 1 ounce of any powdered soap (or 3 ounces of powdered acti vated carbon) and shake for 5 minutes. Ig. Discard water and again put in 2- 3 gallons of water and shake. **15 5 . Discard rinse water and fill to overflowing with water. Discard this water. 6. Pill with water to be used for drinking purposes. Water thus stored should be used within a few days. Cans placed in water service rust rapidly and should be cleaned to remove as much rust as possible before each filling. It would be preferable, if possible, to discard used -cans and to use only fresh cans for water service. B. 50"G-allon Gasoline Drums . 1 . Choose drums that show no interior scale. The in teriors should be bright and the galvanized coatings clearly discernible. 2 . If steam is available, steam for l/ 2 to 1 hour and proceed with step ov o below, depending on the quantity of water available. 5 . If no steam is available, aerate for 15 minutes with compressed air. 4 Add 10- 20 gallons of water, 1 lb. of powdered soap, and shake by rolling the drum back and forth for 15 minutes over a short distance. Discard contents. 5 Put in 10- 20 gallons of water, l/ 2 lb. of activated powdered carbon, and repeat rolling operation. I Discard contents. 6. Remove residual carbon by rinsing repeatedly with-, small portions of water. 7 . If time permits and a sufficient supply of water is available, fill drum to overflowing and discard its contents - l4- 8 . Pill drum with drinking water. Water may b'e stored in these drums for at least 8 days. White sediment (zinc compounds) m a y b e filtered off through sev eral folds of closely woven cloth or flannel. If there is a white scale on the interior of the drums, the lead content of the water may increase to above 0, 10 p.p.m. In this case, and also if neither steam nor compressed air is available and step 7 must be omitted, the water may have an appreciable gasoline odor. It may be made fit for use, however, by filtering it through the carbon filter case shown in Figure 1 . For most efficient operation, renew the carbon filler for each drum of water filtered. An al i> s. ternative procedure is to add 1 lb* of powdered activated carbon to the water in the drum, shaking it for 10- 15 minutes. The carbon may be filtered off through several folds of finely woven cloth or flannel. C. Gasoline Tank-trucks 1 . Drain gasoline as completely as possible from com partments, 2 . Steam each compartment for not less than 9O minutes, (A steam jenny such as Is used by building cleaners is satisfactory.) 3. Flush out loose scale with a pressure water hose. Ip. Fill to overflowing with water in order to displace all gasoline. 5 * Drain to the gage level. Water thus transported may be used without further treatment (other than possible chlorination) up to l8 hours after -15 filling, if it shows no color or sediment. If the water has be come strongly colored and has picked up sediment, its appearance may be considerably improved b y passing it through the standard army mobile or portable purification unit. This procedure not only removes color and sediment but also decreases the gasoline odor and lead content of the water. All water stored longer . than 18 hours in trucks with iron tanks should most certainly be filtered' through the sand filter to remove lead, for the lead o-ontent may have risen above the tolerance limit of 0.10 p.p.m. Increased assurance as to safety of the water may be provided by adding 0.5-1 gram of powdered activated carbon to each gallon of water*, after its collection. After thorough mixing, the carbon should be allowed to settle for several hours and the water should be completely clarified by filtration through the mobile or port able water purifier. Trucks once cleaned and placed in water service improve with use insofar as odor and lead content are concerned, but should be flushed with a hose before, each filling to remove scale and rust which will otherwise color the water after only a short period of storage. D. Gasoline Tank-cars . 1. Steam for not less than 6 hours. (Locomotive steam or powerhouse boiler steam must be available.) 2 . If possible (caution-?:-) have a man enter the tank car to flush away all loose scale on the surfaces of the tank, by means of a hose and a stream of water under pressure, 3. Pill to overflowing with water to displace any gaso line remaining in pockets, etc. -l- I[_. -Drain water to level of dome. -"-Caution: A gasoline tank-car should not be entered in the absence of facilities for testing its freedom from harmful or explosive gasoline vapors, except with the following precautions: 1. The man who enters shall be equipped with a full face-piece (covering the eyes, nose, and mouth) or with partial face piece (covering nose and mouth)' and goggles, to which is connected a canister with an adequate supply of fresh acti vated charcoal, or a hose line with a constantly supplied and adequate stream of fresh air. The Army service mask will be adequate, if the canister, is fresh, but after use in entering a tank-car the canister should be replaced by a new one. 2 . A safety line shall be firmly secured to the person entering the tank, by means of a suitable harness or belt, and led to the outside of the tank into the hands of observers who shall be constantly prepared to remove the individual from the tank at the first sign that he is being affected by gasoline vapors. At least two persons shall be present on the outside to rescue the entrant, and to resuscitate him if need be, by prompt application of artificial respiration. 3 . Care against fire or explosion must be taken by all persons in and on the tank-car by employing spark-proof tools and nozzle, and wearing shoes free of hobnails.. In using water transported in gasoline tank cars, the same precautions should be followed as in the case of tank-trucks. In the case of tanks (either trucks or cars) which show heavy rust and scale deposits, flushing away of the deposit may open up pockets containing droplets of gasoline or uncover fresh surfaces that may be high in their lead content. The result may be to increase the gasoline odor or the lead contamination of the water. Possibly such pockets open up after water has been stored in the tanks for extended periods and this may account for the gradual increase in the gasoline odor and lead content noticed especially in the rustier tanks. Many of these pockets can surely be eliminated in the case of tank-trucks, if the walls are hosed prior to the steaming operation, in addition to the final -17" hosing. In the case of tank-cars, it may be good practice to interrupt the steaming after 1|. hours in order to hose down the walls. The steaming should then be continued for 2 hours longer, followed by the final hosing procedure as outlined in the recom mendations. . Since this study was carried out principally during the summer months, it is probable that the results are representative of the worst conditions, because of the generally increased chemi cal activity attending high temperatures, ' Kettering Laboratory Of Applied Physiology Experimental work performed by: J. Cholak, Ch.E. R. R. McNary, Ch.E., A.M., Ph'.D Karl Bambach, A.B., Ph.D, R. K. Burkey, B.Ph. Approved Robert A. Kehoe, M.D., Director Date: December 15, 19^2 Report prepared by: J. Cholak, Ch.E, //T000029 Table 1 Relative Effectiveness of a Number of Materials In Removing Inorganic Le Organic Lead, and Gasoline Odor from Drinking Water Materlal Milliequivalents of Pb as PbNOa removed/g. material Powdered Activated Carbon 2.8 Amberlite 1R- 100 i*5k Zeo Karb . 1.60 Activated Alumina Amberlite lR-lf. o ,55 . 0.1*2 . Puller's Earth 0.1*2 Supercell 0.196 Sand 0.166 Milliequivalents of PbEtsBr rernoved/g. Materlal 0.81 O.98 1.07 0.01 Practically nil Practically nil Practically nil Practically nil T.O.-"* Val after Abso _N l 5 1 l^O ml. of water with a T.O. value of 300 used with l^g. of material in these test o O O O P; Ife'#-' * $&?. fei-. fl le Table 2 Removal of Inorganic Lead, Organic Lead, and Gasoline Odor from Water b^ Granular Carbon Filter Bed [+2 11 D by 22_ Deep - (Rate Filtrate 2. 5 gallons/sq. ft. area) (1 ) .10 mg. Pb (inorganic) per liter distilled water-::- (2 ) 7 ppm. lead triethyl' bromide in tap water-::- (3) Water saturated with;gasoline . (4 ) Tap water mildly contaminated with lead (0. 12 p.p.m. , each of organic and inorganic lead), plus gasoline to give a T.O. value of 100 .16,000 gal. 1,1+30 gal. . 10. 000 gal. (To T.O. 29. 000 gal. (To T.O. m:) --Tests were discontinued when Pb content of 0. 10 p.p.m,. was reached, mi ll: m, V A Table j5 Removal of Lead and Gasoline Odor from Water by x 6 11 Granular Hydrodarco Bed In Filter Case '(of Figure 1 ) Pb in wa Run Water artificially contaminated Pb content Amount filtered at end of by analysis (gallon) p.p.m 1 0.5 p.p.m. inorganic'lead + 2 p.p.m. organic lead + gaso line odor 5. 05 p.p.m. , 0.105 2 Same as above ' 2.56 p.p.m. 58 0.16 3 0.5 p.p.m, inorganic lead + 0,5 p.p.m. organic lead + moderate gasoline odor l.lo p p * l 1 9 J.o ' 0.11 k 0.1 p.p.m. each of organic and 0.29 p.p.m. inorganic lead and gasoline odor to T.O. value of JOO 122 O.OJO Table Ij. Lead Content and Gasoline Odor of a ter Stored In 50-Gallon Drums, Following Treatment with 1 Pound of Powdered Activated Carbon W:-' wHT------------ :----------m .4 . Drum 1 Drum iZ- Duration of storage w Pb in filtered water p.p.m. Gasoline odor in water Pb in filtered water p.p.m. G Control - 0.30 Very strong 0.20 10 min.-::- 0.025 20 min.-::- 0.017 30 min.-::- 0.005 Very faint 0.025 60 min. 0.000 Very faint . 90 min. 0.000 Very faint 120 min. 0.015 Very faint . 18 hr. 0.020 Very faint 0 ? 214. hr. 0.011 Ip2 hr. 0.016 Definite 3.5 days 0.018 Definite 5.5 days 0.009 Definite 6 .5 days 0.010 Definite -::-During these periods the drums were shaken. Table t5 Lead Content of Water Following Prolonged Storage In 1 Gallon Tin Cans Experiments with Various Types of Water . Type of Water Cincinnati City Water Cincinnati City Water + Cls (5 p.p.m.) Norwood City Water Norwood City Water + Cl2 (5 p.p.m.) Distilled Water pH Water before storage 7. 89 7.80 . 7* 57 7. 1 6.5 Pb (p.p.m.) Before . After After Storage 1 week 2 weeks 0.016 0.006 0.007 0.001 0.005 0.005 ' 0.002 0.007 o.ooi^ 0.005 0.005 0.0014. O.OOJi 0.006 0.007 Table 6 50Lead. Zinc, and Gasoline Odor In Water Aftefr Prolonged Storage In -Gallon Gasoline Dr Drum No. Cleaning method '. Control Water from city main Storage period 1 day 2 days Pb Zn Pb Zn p.p.m. ,P,p." p.p.m. p.p.m. 0.006 0.10 ij. days 8 days Pb Zn Pb Zn p.p.m. p.p.m p.p.m. p.p.m. 1.331 Washed with soapy water, 0.015 0.018 2.70 O.O36 4*6 0 O.O3O 6.1 Str cre rinsed, flushed and filled sed hou 2 The same 345 5.8O.O4.8 0.029 3.5O 0.031 4..00 0.030 The 3 The same 4-95 470.020 2 . 4 0.019 2.4.O 0.029 O.O55 The k The same 0.011 1.31 0.010 I.83 0.010 4.90 0.012 J..6 The 5 The same 0.034 11^70.021 1.I4-3 . 0.022 3.70 0.025 7.6 The 0.135 3.176 The same (white scale on 1.11 O.O9O 1.80 O.I3O 2.25 0.060 The interior of drum) 7 Aerated with pressure hose, washed with' soapy 0.011 2.2 0.012 3-9 0.010 45 O.OII4. 2.85 No g water, rinsed with water 0.17* as and powdered carbon 78 The same as ( ) 60Steamed for minutes 9 and rinsed (white scale on interior of drum) 0.010 5.8 0.020 0.55 0.015 60..8U5* 0.009 349 O.OI4.O 1.27 O.Olj.0 1.55 0.012 2.72 O.O5O 245 The Gas 3samp rd Represents soluble zinc content of water after removal of suspended material by filtration. Table % Lead Content and Odor of Water Transported and Stored In Gasoline Tank Truck Truck //I -- 805 Gallon Capacity -- Sohlo -//1|1{,10 (3. Years Old) Capacity of compartment gallons JOO Treatment 90 min. steaming, flushed to remove loose scale; filled to overflowing, emptied, filled to gage level Control, not steamed; other treatment same as above After 20 min. After ip hr. Pb Pb p.p.m. Odor p.p.m. Odor 0.032 + 0.020 + 0.066 ++++ 0.115 ++++ After l6 hr. Pb p.p.m. Odor 0.013 + O.OlpO ++++ 'j ! C\J 60 min. steaming; otherwise 150 same as J00 0.029 + 0.015 + 0.025 + 30 min. steaming; otherwise 105 same as JOO O.O39 + 0.016 + + 0.026 ++ k After steaming operation, compartments appeared slightly rusty, with little loose |y sediment, and very slight odor from steamed compartments. Average threshold odor value of water stored in steamed compartments - 5, unsteam Waters acquiree some color in ip hours with marked increase toward end of run. Sli X taste was observed after If. hours. In general, there was no objectionable taste. f ; Lead content of water from Cincinnati mains, used In this and all subsequent tests where noted), = 0.008 p.p.m. m Table 8 ii, m: Lead. Content and Odor of Water Transported and Stored In Gasoline Tank Truck fs`> Truck #2 - 823 Gallon Capacity - Sohio #i|,616 - 2-1/ 2 Years Old Capacity of compartment gallons 35 255 Treatment 90 min. steaming, flushed to remove loose scale; filled to overflowing, emptied, filled to gage level Control ~ not steamed; otherwise same as 305 After ]L hr. Pb ' p.p.m. Odor O.O3O + 0.029 ++++ After 1 hr. Pb p.p.m. Odor 0.031 + 0.029 ++Jr+ After IL8 hr. Pb p.p.m. Odor 0.019 + 0,016 ++++ 60 min. steaming - other 15 5 wise same as 305 0.029 + 0.013 + 0.010 + 30 min. steaming - other 110 wise same as 3^5 0.015 + 0.012 + 0.013 + Following steaming, compartments had faint but distinct gasoline odor, with somewha and sediment than in case of truck 1 . The water in all compartments (except contro from oily taste. There was somewhat greater pick-up in color and sediment after I4. ing than in case of truck 1 . There was slight odor in water; disappeared on heatin exposure to air. Color and sediment were completely removed by addition of 1 g. ca gallon and filtering. ' Table a Lead Content and Odor of Water Transported and Stored in Gasoline, Tank Truck Truck #3 " l600 Gallon - "Autocar" Trailer - Ethyl "Q" Service g?;_ Capacity of compartment gallons 300 575 550 s: 575 Treatment 30 min. steaming, flushed to remove loose scale; filled to overflowing, emptied, filled to gage level 60 min. steaming; flushed to remove scale; filled to gage . Control - not steamed; other treatment same as 300 above 90 min. steaming; other treatment same as ~$QQ above After 30.min. After ,4- hr. Pb p.p.m. Odor Pb p.p.m. Odor After 18 hr. Pb p.p.m. Odor 0 .0l|2 + 0.07^ + O.O53 + o.olj.1 + O.O39 + 0.088 4*4* 0.038 ++++ O.Ol+O ++++ 0.01+2 ++++ 0.017 + 0.020 + 0.027 + Steamed compartments had a very slight odor before filling. All compartments were fife- and had loose scale which was flushed a w a y . - Odor and taste of water in steamed com |L were about the same as in previous tests. Pick-up in color and sediment was the sa is other tests. .I I /Water from compartment 375* when filtered through sand bed, gave clear, colorless w ; lead content reduced to 0.01 p.p.iu. '. . .. . i' Table 10 'A Lead Content and Odor of Water Transported and Stored In Gasoline Tank Tru Truck #1). - 500 Gallon Capacity - In Use for at Least 15 Years Compartme ft Capacity of compartment gallons 280 lipO 75 Treatment 90 min. steaming, flushed to remove loose scale; filled to overflowing, emptied, filled to gage level 90 min. steaming; flushed to remove scale; filled to gage . ' Control - not steamed; other treatment same as 280 above After JO min. After Ij. hr. Pb Odor Pb Odor p.p.m. p.p.m. O.Oij.O * O.O65 ++ 0.090 + O.O85 ++ 0.275 ++++ O.37 ++++ After 18 hr. Pb Odor O.O85 ++ O.O75 ++ 0.5^0 ++++ Somewhat Increased odor in water stored in steamed compartments, but oily taste abs increase in color and sediment, particularly after Ip hours' storage. Water from c after 1|2 hours' storage was filtered through sand filter; it was then clear and col lead content reduced to 0. 006 p.p.m. Slight odor was present, but disappeared rapi to air. I I;'1'-' IE  $able 11 Lead Content and Odor of Water Transported and Stored In Gasoline Tank Trucks 80.82 750 575U.S. Army Truck # lj - Gallons - Two -Gallon Compartments Compartment 1 Treatment 90 min. steaming, flushed to remove loose scale; filled to gage After 1 hr. Pb p.p.m. Odor __________ t 0.006 None After ij hr. ---- p.p.m. Odor 0.008 None 21 5After hr. After Ip hr. Ph p.p.m. -- Odor ~~ Pb -- P*P.rc. Odor 0.009 None 0.008 None 2 180 min. steaming; same as above 0.005 None 0.007 None 0.010 None 0.010 None Following above test, both com1 partments were emptied and re- 0.011 None 0.009 None o.oolp None -- -- filled with water (second filling). 2 Same as above 0.007 None 0.006 None O.OOlj. None O.OOij. None Third filling - Following above ----- 1 test, both compartments were 0.002 None 0.002 None O.OOij. None 0.005 None flushed out with hose and immediately filled with tap water ' 2 Same as above 0.007 None 0.002 None 0.007 None 0.005 None 5Note: This truck evidently had not been In recent gasoline service. It was contaminated with gasoline gasoline In It for days. Before steaming and introducing the gasoline, accumulated rust and s away. 12.-1 T^ble Performance of Wallace and. Tiernan Portable Water Purification Unit Run Type of water 8 ;82 60City water stored in Army truck Control # ol for hours. (Rust and sediment) 11 Water contaminated by adding O.15 Runs - ; p.p.m. total lead (0.10 inorganic + 0.05 organic) + small amount of gasoline Run 5 Uncontaminated city water run following backwashing of Unit 11to remove sediment collected in Runs - ; Run 6 0.15Water contaminated with inor ganic Pb ( p.p.m.), passed 5through unit following back washing after Run Run 7 01;0Water contaminated with Pb ( . p.p.m. -- O.3O inorganic 1+ 0.10 organic) + gasoline. Water treated with lb. activated carbon before pass Run 8 ing through unit. 11City water contaminated as in Runs - ; but adjusted to pH i-? -- -_____________________ Pb before passing thru unit p.p.m. 0.16 0.007 0.15 0OX & }; 0.15- Water passed thru unit gallons 750 3000 750 750 750 750 Pb in effluent water (range) p.p.m. 0.01 O.O6-O.O75 0.007-0.010 0.030-0.0l;5 0.015-0.030 O.O65-O.O75 Pb in effluent (average) p.p.m. 0.01 O.065 0.008 O.O35 0.020 O.O69 Appea o wat Clear Color Clear Color Clear Color Clear Color Clear Color Clear Color Kota: pH of water in runs 1-7= 7*8 - 8.1; Analysis made at end of each 187.5 gallons of effluent. Reduced from O.58 p.p.m. after addition of carbon. Table 15 Lead and Gasoline Odor of Water Stored in Gasoline Tank Cars 4 Car No, Capacity gallons Treatment GRCX 2951 8117 Steamed 12 hours. Hosed to remove loose scale. Rilled to over flowing and drained. Pilled to gage mark. A After 1 hr. Pb p .p ,m. Odor After !(. hr. Pb p.p.m. Odor Aft Pb p.p.m. Very . Barely 0.01 faint 0.007 perceptible 0.006 Steamed 6 hours. GRCX 28J72 8096 Hosed to remove loose scale. -- O.OOlj. Very faint 0.011 Filled to over flowing, drained to gage mark. Above water emp GRCX 28i|2 8096 tied and tank re <-- -- 0.006 ? 0.009 filled to gage. GRCX 28i|2 8096 Above water ad justed to a pH of 5. 0 1 hr. after mixing 0. 055 (b) 0.031 ? (b) 0.029 Note: Water employed was well water at pH of 7 5 * Lead content 0, 007 p.p.m. No (a) Very slight yellow-red color, perhaps due to dye of gasoline, (b) Slight but significant increase in color. IO o co o co o o I VH I