Attachment 12

Memo on Plutonium Contamination at the Nevada Test Site

     Monthly Activities Report No. 22 (U), Col George Webster,
May 4, 1956.
FCDV/[illegible]

                                                  4 MAY 1956

SUBJECT:  Monthly Activities Report No. 22 (U)



TO:       Chief, Bureau of Yards and Docks
          Department of the Navy
          Washington 25, D.C.


1. Reference is made to letter, Bureau of Yards and Docks [illegible] 
of 23 January 1951, and in accordance therewith the following 
information is supplied for the Month of March 1956.

2. Field Work
	a. Since mid-January 1956, the major field effort of Division
[illegibile] Snadia Corporation has been concentrated on a program to
determine plutonium contamination hazards from accidental [illegible]
decontamination of the "sealed pit" type nuclear weapons. These weapons
are fabricated with the active material as an integral part of the 
device. Knowledge of plutonium contamination hazards is required by the 
AEC in order to establish safety procedures for manufacturing, 
assembling and handling facilities.

	b. Briefly, Department [illegible] has established a pattern 
of 100 situations at which "sticky plates" will be located to 
[illegible] fall-out  from surface bursts. Since plutonium itself is 
too hazardous and too [illegible], uranium has been substituted. It is 
[illegible] that plutonium contamination can be inferred from the 
measured uranium fall-out. Initially the [illegible] of requested
[illegible] weapons (includes detonators, [illegible], high explosives, 
[illegible] will be used to furnish uranium fall-out. It is planned that 
some weapons will be [illegible] on asphalt surfaces. Single [illegible] 
points will be located on the top, sides, and on the bottom after a 
sufficient quantity of samples have been recovered from [illegible] 
bursts of the [illegible], several "sealed pit" type  weapons may be 
destroyed.

3. Office Work
	The following reports which may be of interest to [illegible]
have been issued in Department [illegible] Sandia Corporations.

	a. [illegible] "Activation of stockpiled Metals and Ores,"
[illegible]. In this report an estimate is made of the hazard from 
weaponsburst near enought to stockpiled materials that the induced 
radiation willmake them difficult to approach or use. This hazard 
turns out to be small compared to that from normal radioactive fall-out 
from surface bursts. Probably any bomb [illegible] to activate a 
particular stockpile of material will also be [illegible] enough to 
[illegible] it about.

	b. [illegible] 

	c. [illegible] Plutonium contamination levels at the Nevada 
Test Site are believed to range as high as 100 times the maximum 
"safety level" for laboratories, while islands of Bikini Atoll may be 
contaminated to [illegible] times laboratory tolerance level. This 
tolerance level is normally taken as [illegible]microgram of plutonium 
per square meter of surface, [illegible] the practice of centralizing 
[illegible]. There is a need to evaluate better the field inhalation
hazard [illegible] with given levels of surface contamination.

	For the Commander:

	George B. Webster, Jr. 
	[illegible]
	Acting Deputy Chief of Staff
	Development

[illegible]
[illegible]