53. 



DR. C. V. THEIS: Do you keep putting liquids in the pits? 



MR. MORTON: Yes. They were transferred formerly by tank 

 truck, but a pipeline has been built and about 7 5,000 gallons are 

 pumped to the pits every two weeks. The chemistry of the wastes is 

 different from those described by previous speakers. These wastes 

 contain 25 to 35 per cent of dissolved solids by weight. The principal 

 bulk constituents are sodium and ammonium nitrate. The principal 

 radioisotopes are ruthenium and cesium. There is only a small per- 

 centage of aluminum. 



DR. GILLULY: What happens to the stuff? Is it diffused? 



MR. MORTON: It appears to diffuse gradually through the soil, 

 the nitrates preceding everything else. The ruthenium diffuses, but 

 none of the other isotopes have been found in wells 50 to 75 feet from 

 the pit. We have not detected strontium as yet, although strontium 

 has been present in the waste going into Pit No. 3 since January 1955. 



DR. KOHMAN: What fraction of what you put in has seeped out? 



MR. MORTON: The total input to the pits has been over two and 

 a quarter million gallons, and there are about one and a half million 

 gallons in them now. There has been loss by seepage but the exact 

 amount is not known. In connection with these pits we have tried to 

 collect data which will be of value in studies on high level waste dis- 

 posal and on further use of pits for intermediate level wastes. One 

 subject for investigation is the amount of seepage in this particular 

 formation. Detailed explorations have been made by the Geological 

 Survey of the character of the formation, the structure, and the hy- 

 drology in this area to help determine the amount of seepage. A care- 

 fully planned series of observations will be made during the next year 

 to determine the evaporation from a pit of this configuration. If we 

 know the waste input and the rainfall contribution, and can estimate 

 the loss by evaporation, then we have a measure of the seepage. An 

 approximate estimate is that the evaporation loss is about 30 to 35 

 inches a year and that rainfall contributes about 50 to 55 inches a 

 year. The liquid wastes added are about 35,000 gallons per week into 

 the two pits . 



DR. KOHMAN: The original intention was to have no seepage? 



MR. MORTON: No. These pits were intended primarily to pro- 

 vide increased storage volume. It was assumed there would be some 



