o the
Assembled by
Edward F. Eldridge
Technical & Research Consultation Project
Public Health Service
Region IX
Portland, Oregon
November, 1960

In May 1957 the Public Health Service initiated the "Tech-
nical and Research Consultation Project" as a means of better
reaching and serving those engaged in water pollution research
in the Northwest. A series of symposiums have been held as one
of the activities of this Project. The purpose of these symposiums
is to provide an opportunity for a free and informal exchange of
knowledge on subjects related to water pollution. The following
is a list of the subjects covered by the seven symposiums held
to date:
1.	Research Relating to Problems of Water Pollution
in the Northwest
2.	Financing Water Pollution Research
3.	The Slime (Sphaerotilus) Problem
4.	Short-term Bio-Assay
5.	Siltation - Its Sources and Effects on the Aquatic
6.	Oceanography and Related Estuarial Water Problems
of the Northwest
7.	Status of Knowledge of Water Problems of the Northwest
8.	Radioactive Waste Problems in the Pacific Northwest
These proceedings are compiled from the prepared papers and
discussions of the Eighth Symposium held in Portland, Oregon on
November 15, 1960. The agenda has six major parts, each with
one or more persons with special knowledge and experience in the
specific subject discussed. Each of these persons presented pre-
pared statements which are included. The discussions were recorded
and are abstracted in these proceedings.

9:00 A.M.
9:05 - 10:00
10:00 - 10:45
10:45 - 12:00
1:00 - 2:00
2:00 - 2:45
2:45 - 4:30
Tuesday, November 15, 1960, Rm. 104, U.S. Court House
Building, Portland, Oregon
Introductory Remarks - E. F. Eldridge, Physical Sciences
General Fundamentals and Instrumentation. Prepared
remarks by Dr. Arthur Scott, Department of Chemistry,
Reed College and Dr. John Thorpe, Assoc. Pathologist
and Director of Isotopes Laboratory, Good Samaritan
Hospital, Portland, Oregon.
Prepared remarks by Dr. Ernest Tsivogolou Robert A.
Taft Sanitary Engineering Center, Cincinnati, Ohio.
Methods of Waste Disposal: Prepared remarks by R. L.
Junkins, General Electric Co., Hanford, Washington
Biological Considerations: Prepared remarks by Dr.
Richard Foster, General Electric Co., Hanford, Wash.
Prepared remarks by Robert Stockman, Washington Depart-
ment of Health, Seattle, Washington.
Prepared remarks by Curtiss Everts and Jack Weathersbee
Oregon Department of Health, Portland, Oregon.
Alaska. Prepared remarks by Dr. Allyn H. Seymour,
Deputy Director, Committee Environmental Program
Project CHARIOT, University of Washington, Seattle,
As Tracers: Prepared remarks by Dr. Warren Kaufman,
Engineering Department, University of California,
Berkeley, California.
For Flow Measurement: Prepared remarks by Dr. Bernard
A. Fries, California Research Corporation, Richmond,

November 15, 1960
Assembled by
E. F. Eldridge *
Introductory Remarks - E. F. Eldridge
This is the eighth of a series of symposiums which have been
held in this area on subjects related to water pollution. Today we
are discussing certain phases of the problem of radioactive wastes.
We hope through these discussions to delineate present-day
and anticipated future problems of radiation in waters of the
Northwest and to mark out areas of needed research to meet these
This is one of the most important and timely subjects we have
discussed. Progress in the use of atomic energy both for defense
and peace time purposes is so rapid that we have little time to
waste in our consideration of the problems of waste disposal. We
may not find any definite answers through our discussions today,
but I am sure we will all leave with new ideas and interests.
Because of the nature of this subject it seems desirable to
first discuss some of the general fundamentals of radioactivity and
the units and instruments used in its measurement. A glossary has
been prepared in order that we all will have the same understanding
of terms used.
* Physical Sciences Administrator, Department of Health,
Education and Welfare, Public Health Service, Water Supply and
Water Pollution Control Program, Pacific Northwest, Portland,

Arthur Scott*
According to accepted theory atoms consist of a nucleus
surrounded by a cloud of electrons. Our discussion today will
be concerned primarily with the nature and properties of the
nuclei of atoms; and, when we shall want to emphasize this, we
shall use the term "nuclide" rather than "atom."
Nuclei of atoms are composed of combinations of two
particles which are generally referred to as "nucleons": the
proton and the neutron. The proton is the nucleus of the hydro-
gen atom; it has a single (+) electrical charge and a weight of
approximately unity on the ordinary scale of atomic weights.
The neutron carries no electrical charge and, like the proton,
has a weight of approximately unity. The number of nucleons
making up the nucleus of an atom is called the "nucleon number"
or "mass number" of the atom and represents the approximate
weight of the atom on the atomic weight scale. The nucleon
number is usually used to identify different isotopes of the
same element: e.g., U-235 and U-238. In passing it may be
noted that the nucleus of an atom carries a positive charge
numerically equal to the number of protons present, which is
referred to as the atomic number of the atom. The atomic number
of an atom determines the chemical properties of that atom;
because it determines the number of (-) charged electrons in
the cloud surrounding the nucleus of the atom and these electrons,
in turn, establish the chemical behavior of an atom. For example,
to be precise in describing the two isotopes of uranium we could
write 92*^^ an(* 92^ where 92 is the atomic number of uranium.
For most purposes, however, the atomic number is superfluous
since the symbol of the element indicates clearly the chemical
properties of the atom.
Nuclides fall into two classes: stable and unstable.
In the case of an unstable or radioactive nuclide the nucleus
undergoes a spontaneous transformation to form a new and different
nucleus, which may or may not be stable. The transformation
*Dr. Arthur Scott, Professor of Chemistry, Reed College
Portland, Oregon.

process is generally described as the radioactive decay or dis-
integration of the nucleus. Some radioactive nuclides are found
in nature. Radioactive nuclides of most elements can be prepared
by nuclear reactions which will be mentioned later. The fission
of U-235 also results in the formation of radioactive nuclides as
will be described later.
The radioactivity of a given sample of a radionuclide is
specified in terms of the number of disintegrations taking place
per second of time. The unit of radioactivity (or activity) is
the "curie," (abbreviatedrc) defined as 3.7 x 10^ (37 billion)
disintegrations per second. Smaller units of activity which are
convenient for certain purposes are
millicurie (mc) = ^ curie
microcurie (>ic) = 	1	 curie
The activity of any radionuclide is proportional to the number
of unstable atoms present. For example, a 10 mc sample of 1-131
contains 10 times as many unstable 1-131 atoms as does a 1 mc sample.
Radioactive disintegration of an unstable nuclide is
characterized by two things: (1) the rate at which the decay
takes place; and (2) the nature of the radiations emitted by the
disintegrating nucleus. These features of the disintegration
process will be discussed briefly.
The rate of decay of a radionuclide is generally expressed
in terms of its half-life (T), i.e., the length of time required
for the disintegration of one-half of the radioactive atoms present
in a given sample of the radionuclide. For example, since the
half-life of 1-131 is 8 days, one half of the 1-131 atoms present
in any given sample of 1-131 will disintegrate and disappear in
8.0 days. Or to put it in a different way: if we start out with a
10 mc sample of 1-131 we shall have 5 mc after 8 days, 2.5 mc
after 16 days, 1.25 mc after 24 days, and so on. Half-lives of
radionuclides vary over a very wide range: some half-lives are
as short as microseconds and some are known to be of the order
of billions of years.
In the process of disintegration an unstable nucleus emits
or ejects a particle with considerable kinetic energy, which may
or may not be accompanied by radiation similar to hard (penetrating)
x-rays. The particles emitted are one of two kinds, alpha or beta

which will be identified more fully below - the x-ray like radiation
emitted by a disintegrating nucleus is called gairana radiation.
The alpha and beta types of radiation can be described
briefly in general terms.
Alpha. An alpha particle is the nucleus of a helium atom and
can be represented by 2He^. When it is ejected by an "alpha
emitter", the atomic number and nucleon number are less than
those characteristic numbers of the emitting nucleus by 2
and 4, respectively. For example:
226 *	222 .* *	218
Ra	Rn	Po	
T=1600 y	T-3.18 d
In this example the product or daughter nuclide is also
unstable and we have a radioactive chain. It should be
noted that alpha particles from a given radionuclide all
have the same energy.
Beta This term applies to two different kinds of high energy
elections: negations (B~) which are ordinary elections
with a (-^ charge; and positions which are elections with
a (+) charge. The emission of a beta particle by a nucleus
does not change the nucleon number of the nucleus; it
does, however, cause the atomic number of the nucleus
to change. When a B~ is emitted the atomic number is
increased by one and when a B+ is emitted the atomic
number is decreased by one. For example,
p32 yr	g32
T=14 d
It should be noted here that the beta particles from a
given radionuclide cover a range of energies. The maximum
energy, however, is characteristic of a radionuclide.
Since we are going to be concerned primarily with the effects
of the radiations from radioactive nuclides, we shall consider them

in more detail, touching on the following topics: their detection;
the energy of the radiations; their range or penetrating ability;
and the energy which the different radiations deposit in samples
of material which are exposed to them.
In discussions of nuclear phenomena it has become customary
to consider energy changes relating to a single, individual atom
or nucleus; and this has led to the use of a small unit of energy,
the electron volt (ev). It will suffice here to say that chemical
reactions when reduced to individual atoms or molecules involve energy
changes of less than 5 ev, whereas nuclear reactions on the same
basis involve millions of electron volts. For convenience, in
connection with nuclear reactions, one makes use of the energy
unit "mev" which is equal to 1,000,000 ev. Unless otherwise spec-
ified the mev unit is used in specifying the energy of radiations
from radionuclide. Illustrations of this usage will be cited below.
It should be noted that the energy of alpha and beta particles
refer to their kinetic energies. Gamma radiation, however, appears
to act like a bundle or atom of energy and this unit is termed a
photon; and the energy reported for gamma radiation refers to the
energy of its photon.
Alpha, beta, and gamma radiation in passing through matter
can ionize the atoms of which the matter is composed; that is to
say, an election outside the nucleaus is knocked out of the atom
leaving what chemists call an ion. The ion and electron produced
in this way are generally referred to as an "ion pair." In the
case of air molecules about 35 ev of energy are required to produce
an ion-pair. All the common means of detecting nuclear radiation
depend ultimately on the ionizing effect of this radiation.
The harmful consequences of nuclear radiations to living
organisms are generally supposed to result from chemical effects
caused by the ion-pairs produced by the radiation in question.
It is assumed therefore that in any given case the extent of bio-
logical damage resulting from exposure to radiation will be related
directly to the amount ionization caused by the radiation, that is,
to the amount of radiation energy deposited in the biological sample.
The most general unit of radiation absorption is the "rad" which
is defined as "the absorbed dose of any nuclear radiation which is
accompanied by the liberation of 100 ergs of energy per gram of ab-
sorbing material." For practical purposes in the case of soft
tissue, the rad is equivalent to the older units: roentgen and rep.
Although all radiation from radioactive decay is ionizing the
mechanism whereby the radiation produces ion-pairs is not the same
for gamma radiation and particulate radiation (alpha and beta) and

it will therefore be simplest to treat these two kinds of radi-
ation separately.
Gamma radiation. A beam of gamma radiation can be pictured
as a stream of high energy photons. In passing through, say, 1 cm
of material a certain small fraction of the photons will be absorbed
and converted into ion-pairs. This attenuation of the gamma beam
depends on the nature of the material. In the case of air the
attenuation is extremely small (about 0.0057.), an amount which
is negligible for many purposes. (See discussion of "inverse
square law" below). Nevertheless, the ion pairs produced even by
this small absorption provide a convenient means of measuring the
intensity of gamma radiation and we find therefore the unit of
ganma radiation defined in this way. The roentgen unit is defined
as that amount of x- or gamma radiation which will produce 2.1
billion ion pairs in 1 cc of dry air under standard conditions.
Instruments to measure the intensity of gamma radiation express
this intensity as roentgens/hour or mllliroentgens/hour. As
mentioned above the energy absorption in tissue for one roentgen of
of fairly high energy photons is essentially equivalent to one rad.
A convenient means of expressing the effectiveness of a
substance in attenuating a gamma beam, that is, in decreasing
its intensity, is to make use of a quantity known as the half-
value layer. This is the thickness of the material which absorbs
half of the gamma photons, fallong upon it and thus reduces the
intensity of the gamma beam by one-half. Values of the half-
value layer for a number of materials for gamma radiation from
Co-60 are as follows:
For example, if the intensity of a gamma beam is 100 mr/hr
it would be reduced to 50 mr/hr by 1.06 cm Ph; to 25 mr/hr by
2.12 cm Ph; to 12.5 mr/hr by 3.2 cm Ph; etc. The same effects
would be produced by using the same multiples of half-layer values
of any materials. It may be noted that it would take an infinite
thickness of material to absorb all gamma radiation from a source.
Finally a word, regarding the inverse square law which has
many practical applications in the laboratory. If a gamma source
can be regarded as a point source and if at a distance df it
140 m
11 cm
5.3 cm
1.65 cm

intensity is known to be 1^ then the intensity Ix at any distance
dx is given by the relationship
or IXI
Thus, if the intensity of a 10 mc 1-131 source at 10 cm is 231 mr/hr
it would be 2.31 mr/hr at 100 cm. This inverse square law assumes
a steady rate of emission of photons from the gamma source, with the
number falling on a fixed area (1 sq cm) varying inversely with the
square of the distance from the source. It is assumed also that
no air absorption of photons takes place.
Alpha and beta. In passing through material all the alphas
or all the betas from a given source give up their energy by degrees.
It can be imagined that each time an ion-pair is formed the kinetic
energy of the particle is decreased by 35 ev and this process is
continued until all the energy is dissipated. The alpha and beta
particles differ from one another in that the heavy alpha particle
is more effective than the beta particle in losing its energy.
This can be illustrated by comparing 2 mev alpha and beta particles
which presumably will produce 60,000 ion pairs before dissipating
the 2 mev of energy. The distances traversed by these particles in
air and in water before they have lost all their energy in formation
of ion-pairs are as follows:
The distances given in the tabulation above are referred to as
the ranges of the particles for the conditions specified. It will
be recalled that the alpha particles from a given alpha-emitter all
have essentially the same energies and therefore will have essentially
the same ranges. The beta particles, however, from a given beta-
emitter have a range of energies with the maximum energy being
characteristic of the emitter. Hence, if the maximum energy of a
beta-emitter is 2.0 mev, the range of the beta given in the tabulation
above is the range of the most energetic beta. The ranges of the
(2 mev)
(2 mev)
1.0 cm
.0013 cm
815 cm
0.9 cm

other betas will accordingly be less than the figures given. It
may be pointed out that since alpha particles dissipate their energies in
in such a short range their localized biological effect might be
considerably greater than the effect indicated by the energy deposited.
In fact their relative biological effect is generally taken as times
that produced by the same dose from gamma and beta radiation.
Activation Analysis
This is a method of analysis which involves (1) making the
atoms of a given sample radioactive, and (2) identifying the atoms
present by their radioactive properties. The method which is quite
powerful in certain cases will be sketched briefly.
The method is based on the reaction of a slow or thermal
neutron (n) with a target nucleus (T) to form a compound nucleus (C)
which is immediately transformed into the product nucleus (P) and
a gamma photon (Y).
T + n
When F is radioactive it can be identified by its radiations
and its half-life. The activity of the product Isotope P produced
depends on the number of T atoms present in the sample exposed to
neutrons, the intensity of the neutron beam (neutrons per sq cm per
second) and a probability factor for the reaction called the cross-
section of the target nucleus. The maximum yield of P, generally
called its saturation activity is obtained upon exposure of the sample
for 3-4 half-lives of P. The following tabulation gives the activities
produced by exposing one microgram of each of the target nuclides
shown, to a rather moderate neutron flux (10* n/cm -sec.), for a
period of 3 - 4 half-lives. The activities of the product nuclei
are given as disintegrations per minute.
Stable target
Activity of
product nucleus
2.6	h
12.8 hr
25.0 m
2.7	d
The activities shown are all readily measurable with the
usual Geiger counting equipment.available in radiochemical labor-
atories. It may be noted that many reactors now have neutron
fluxes 100 to 1000 times greater than the value assumed in the
calculations summarized in the tabulation. In other words with
the 1000 times greater flux the same activity would result with
a target sample of 0.001 microgram.

1.	Activity: Frequently used as a shortened form of "radio-
activity," it refers to the radiating power of a radio-
active substance. Activity may be given in terms of
atoms disintegrating per second. See "curie."
2.	Alpha emitter: A radioactive substance which gives off
alpha particles.
3.	Alpha particles: Often referred to as alpha rays, these are
positively charged nuclei of helium atoms. They are
emitted by radium and other heavy elements and are easily
absorbed in a few sheets of paper.
4.	Atomic waste: The radioactive ash produced by the splitting
of uranium (nuclear) fuel, as in a nuclear reactor. It
may Include products made radioactive in such a device.
5.	Beta emitter: An atom which is characterized by its beta
6.	Beta particle: The name given to the charged electron
emitted from certain radioactive nuclei. Also called
beta radiation or beta ray.
7.	Biologic half-life: The time required for a given species,
organ, or tissue to eliminate half of a substance which
it takes in.
8.	Body burden: The amount of radioactive material in the body
at a given time.
9.	Bone-seeker: Any element or radioactive species which pre-
dominantly lodges in the bone when Introduced into the
10.	Contamination: As applied to radioactive substance, it is
the result of mixing a radioactive material with part
of one's environment. For example, radioactive fall-out
produces contamination of the earth.
11.	Curie: A unit of radioactivity which is numerically equal
to 37 billion disintegrations per second. It is the
amount of radioactivity associated with 1 gram of radium.
One curie equals 1000 millicuries (mc) or 1,000,000 micro-
curies (uc).

12.	Decontamination: The process of removing radioactive con-
tamination from objects or areas.
13.	Dose: A term used interchangeably with "dosage" to 'express
the amount of energy absorbed in a unit volume or an
organ or individual. Dose rate is the dose delivered
per unit time. (See also roentgen, rad, rem, rep.)
14.	Electron volt (ev): A unit of energy which is gained by
a particle of unit electrical charge in being acceler-
ated through a potential difference of one volt. The
symbol Kv (short for kev) is used to describe the energy
of x-rays.
15.	Erg: A measure of energy equal to that required fro an
electron to ionize about 20 billion atoms of air.
16.	Fission products: Also called fission fragments, these are
the split halves of the uranium or other fissionable
atom. They include about thirty-six different elements
and almost two hundred different radioactivities.
17.	Gamma ray: A penetrating ray such as is emitted by radium.
In a medical context, gamma rays are more penetrating
than x-rays. A gamma ray and an x-ray of the same
energy are identical.
18.	Half-life: The length of time required for the decay of one-
half of the atoms in a given sample. For example, the
half-life of radium is 1600 years. If we start with 1
curie of radium (i.e., 1 gram), then in 1600 years we
shall have 1/2 curie. In another 1600 years, the amount
remaining will be 1/4 curie.
19.	Half-thickness: The thickness of a specified absorbing mat-
erial which reduces the dose rate to one-half of its orig-
inal value.
20.	Hot: A slang word which is widely used to descirbe sub-
stances that are unusually radioactive.
21.	Ionizing radiation: Electromagnetic radiation (x- or gamma
rays, or alpha or beta particles or neutrons) which
produces ions as it passes through tissue.
22.	Isotopes: Atoms of the same element which differ from each
other by having different weight. They belong to the

23.	LE),-q: The dose of radiation which is required to produce
death in 50 per cent of irradiated species. Death is
usually reckoned as occurring within the first 30 days.
24.	MPC: Abbreviation for "maximum permissible concentration."
It is that concentration of radioactive material in body
tissue which specialists feel will not produce significant
injury and may be established as a limit for safe oper-
ations in industry or laboratory.
25.	MPL: May be either Maximum Permissible Level or Limit.
It refers to the tolerable dose rate for humans exposed
to nuclear radiation. At present the internationally
agreed upon recommendations stipulate an MPL of 0.3 roentgen
per week.
26.	NCRP: National Committee on Radiation Protection, an advisory
group of scientists and professional people which makes
recommendations for radiation protection in the United
27.	NRCS: The name proposed by the authors for the National
Radiation Control Service, a federal regulatory agency
intended to place restrictions on the use of radiation.
28.	Neutron: A basic constituent of all atomic nuclei. Neutrons
released in the fission process act aa high-speed nuclear
bullets and may produce fission in other nuclei or induce
radioactivity in them.
29.	r unit (or r): The symbol for the roentgen, a measure of
radiation dosage. See roentgen.
30.	rad: A unit intended to extend the definition of the roentgen
to apply to all types of radiation. Technically, it is
the absorption of 100 ergs of energy per gram. It is a
measure of the energy imparted to matter by ionizing
particles per unit mass of irradiated material at the
place of interest.
31.	RBE: Relative biological effectiveness, the relative effective-
ness of the same absorbed dose of two ionizing radiations
in producing a measurable biological response.
32.	rem: Roentgen equivalent man, a dose unit which equals the
dose in rads multiplied by the appropriate value of RBE
for the particular radiation.

33: rep: Roentgen equivalent physical, a unit of tissue dosage
equal to energy absorption of 93 ergs per gram.
34.	roentgen: The standard unit used by radiologists and abbrevi
ated as r. It is a measure of the quantity of absorbed
radiation as defined by the amount of ionization produced
under specified conditions.
35.	Strontium unit (SU): One micromicrocurie of Sr7U per gram of
calcium, usually in bone but now extended to items of food
and milk.

John Thorpe*
The following is a list of the use and approximate
cost of the various instruments demonstrated by Dr. Thorpe:
1. Non-Amplification instruments
A.	Film badge
Personnel monitoring $5. ea, includ-
ing processing.
Lauritsen electroscope Standardization of
other instruments. $200.
Good sensitivity.
For practical pur-
poses, lab. use only.
Pocket dosimeter
Personnel monitoring Charger, $50.
Good sensitivity.
Ea. dosimeter,
2. Amplification instruments
A. Ionization chamber
B. Geiger-Muller
Scintillation counters
Field survey, for
alpha, beta, gamma
radiation. Good
sensitivity. Not
too rugged.
Field survey. Port-
able or fixed. Ex-
cellent sensitivity.
Rugged. Beta and
gamma only. Very
Usually fixed lab-
oratory analytical
instruments. Ex-
tremely high sensi-
tivity. Very ver-
Portable, $200.
Fixed, $700 -
$3000 - 20,000.

We are sorry that the excellent paper of Dr. Ernest Tsivoglou,
Robert A. Taft Sanitary Engineering Center was not cleared in
time to include in these Proceedings. It may be possible to
duplicate and transmit this paper at a later date.

R. L. Junkins**
The wide range of properties and amounts of wastes requires
diversified methods of treatment and disposal to meet all needs.
Each class of waste must be considered separately as well as in
Wastes from the atomic energy industry include high activity,
intermediate activity, low activity and so called non-active wastes.
The different categories are not sharply delineated. "High level
wastes" have been defined elsewhere** as those with "concentrations
of hundreds or thousands of curies per gallon", whereas "low level
wastes" have "concentrations in the range of one microcurie per
gallon". Non-active streams are those which normally contain no
artificial radionuclides. Accepting these broad categories, includ-
ing the intermediate level of wastes, for purposes of discussion,
the wastes can be further categorized as to physical state and other
Because of the wide range in properties of radioactive
wastes, alternative approaches to the disposal problem are necessary.
The high level wastes are concentrated and stored in such a manner
as to isolate the wastes for long periods of time. Low level
wastes are usually released to the environs with or without treat-
ment, depending upon the chemical and physical nature of the wastes,
the volume involved, the available dilution and other factors.
Most of the high level wastes are the liquid wastes which
result from processing irradiated fuel. These liquid wastes are
concentrated and stored in underground tanks. A typical storage
tank of the type in use at Hanford consists of a steel liner sur-
rounded by a concrete shell. Provisions for dissipating the heat
*Dr. R. L. Junkins, General Electric Co., Hanford, Washington.
~~Hearings before the Special Subcommittee on Radiation of the
Joint Committee on Atomic Energy Congress of the United States,
Eighty Sixth Congress First Session on Industrial Radioactive
Waste Disposal.
(This work performed under Contract No. AT(45-1)-1350 between
the General Electric Company and the U. S. Atomic Energy Commission.)

generated by the release of energy through radioactive decay
are also illustrated. The highly concentrated wastes boil in
the tanks, providing an opportunity for further concentration.
The condensed vapors can be disposed of by alternate means or
re-used in the chemical separations process as make-up water.
Through a system of several interconnected tanks, the wastes
can be removed to another tank in the event a leak develops.
Monitoring of the facility to assure integrity of the wastes
storage is required, usually in for the form of inventory of
contents and means of detecting leakage into the surrounding
Other forms of containment of wastes are the common
practices of burial of solid wastes, either directly in the
earth or in subterranean vaults. These wastes are generally
of lower-level than the previously mentioned liquid wastes.
Depending upon the site, leaching of the radionuclides into
fresh water supply may be an important consideration. In any
event, the use of this method of waste disposal usually entails
control of the real estate for many years.
One approach to the development of economical nuclear
power is the "throw-away" fuel concept, in which the fuel is
utilized to a high degree of "burn-up" such that recovery of
fissionable materials by reprocessing of fuel is not required.
Such irradiated fuel elements require storage providing con-
tainment and cooling. The cooling medium then becomes a radio-
active waste stream.
In general, satisfactory methods of waste containment
have been demonstrated during the short history of atomic
energy. Much of the current research and development effort is
aimed at achieving a satisfactory degree of containment at a
reduced cost. In this area some promising work is in progress
toward immobilization of wastes through various processes, some
involving the use of additives and taking advantage of the
heat of the radioactive decay for calcination and fixation. Con-
siderable research has been done toward the possible use of
salt mines as storage receptacles for high level wastes.
Release to the Environs
It is neither necessary nor practical to contain and store
all radioactive waste materials. Some of the waste radionuclides

are so short-lived that they decay to insignificant levels in
minutes. Release of these radionuclides constitutes little
problem if control of the immediate vicinity of the point of
release is maintained.
In cases where longer-lived, biologically important
radionuclides are released to the environs through "low level"
waste streams, prompt dilution is usually desirable. Release
of wastes to the atmosphere or directly to fresh water is usually
done in such a manner as to obtain prompt mixing to the extent
practicable. This minimizes the opportunity for reconcentratio"
by physical, chemical and biological mechanisms.*
"Low level" waste streams of small flow rate are fre-
quently released to artificial seepage ponds, where the water
evaporates and/or percolates through soil into the ground water.
This method of disposal is suited to streams where the content
of radionuclides is lov enough that surface contamination does
not present a problem. In other cases, where the level of
radioactive materials fluctuates or is consistently in the
"intermediate" range, the same type of disposal is used except
that protection from surface movement of the wastes is needed.
This is usually provided in the form of a subterranean void
space, commonly called a crib, covered sufficiently to avoid
wind erosion anH shield the radiation.
Ground disposal requires detailed knowledge of the
earth sciences of the region including the local geology and
hydrology. The capacity of the soil to remove radioactive
materials varies greatly with soil type, specific radionuclide,
etc. The main advantages of ground disposal are:
1.	decontamination of the waste stream by soil,
2.	decrease in radioactivity by radioactive decay during
the time required for the wastes to reach ground water and flow
to a point of potential exposure, and
3.	dilution before reaching a point of possible public
Monitoring of the movements of radioactive wastes through
the soil is a useful means of determining when the capacity of
*In some cases, sedimentation near the point of release
may be a desirable means of removing radionuclides from the waste.
For this and other reasons, prompt dilution is not always advisable.

the soil for decontaminating wastes has been fully utilized.
Based on monitoring results, the need for a new disposal site
can be determined. Movement of the wastes reaching ground
water can also be followed and the time when the wastes may
reach rivers or other points of usage can be predicted.
The adequacy of waste disposal methods is judged by
the resultant radiation exposure to man. Since the early
early days of the atomic energy industry, a conservative
position has been taken in waste disposal practices not only
to keep the exposure within appropriate permissible limits
but also to minimize radiation exposure.

'r5-ss^>Spifej 1



Q: What will be the ultimate fate of the disposal of krypton^
to the atmosphere as regards the operations of Hanford and
the other power reactors?
A: I was reading a report the other day by a group of con-
sulting engineers in which it was indicated that there are
other processes available to remove krypton and other noble
gases; however, they are expensive processes. These engineers
made some assumptions regarding the growth rate of the atomic
energy industry and also presented actual data on its present
status. From this they calculate the exposure that would result
several decades hence. I believe that they came out with some-
thing like 1% of the permissible dose as far as the general
population is concerned. I believe that there will be need in
some of the power reactors for the control of the release
under accident and emergency conditions. The krypton and other
noble gas released under accidental conditions could have some
very serious effects.
Some states have regulations in this regard. A reactor
in Pennsylvania is a case in point. The State of Pennsylvania
restricts the discharge to a magic number of 1590 microcuries
per day. Frankly, I feel that this regulation is too restrictive
and tends to fail to meet the goal of encouraging the development
of atomic energy. Atomic Energy Commission has established
requirements for General Electric as contractors. Other con-
tractors also have regulations which are somewhat different from
those for General Electric.
A: Before a research reactor or power reactor is developed
the applicant first must prepare a hazard report for Atomic
Energy Commission which takes all of the methods that they
will use to prevent the hazard. The report details all of
the methods of disposal of waste. These are, of course, thor-
oughly reviewed and not accepted until there is assurance that
the waste situation will be well handled.
A: This will be a problem differing considerably from that of
pollution control. In the ordinary pollution control program,
each state can operate under its own regulations. Fifty or
more types of regulations on atomic energy will not effectively
solve this problem. We are going to need a unified system of
regulations as the public takes on mor and more of the use of
atomic energy.

Q: The question regards the coolant water from the reactors
which in the case of Hanford is returned to the river.
Will we go to other types of coolant, such as organics,
to avoid the problem of releasing these radioactive
nuclides into the Columbia River7
A: My answer is no. I think it unlikely that we would go
to organic material. I think it more likely that we would
go to recirculation of water. As a matter of fact, one of
the reactors at Hanford is of the recirculation type. The
cooling water returned to the river has been described under
the category of non-active waste and will not contain radio-
active nuclides unless due to corrosion failure in the heat
exchanger. The organic coolants have some advantage in ad-
dition to cooling, since they perform as neutron moderators.
Q: Do you have anything to say about the life of storage
tanks and the degree of saturation of the soil in the
disposal areas?
A: Our experience with storage tanks covers 15 or 16 years
during which time two leaks developed. In both cases, we
removed the contents of the tank to another tank whose
integrity was unimpaired, and are in the process of exploring
the surrounding soil by drilling wells to learn exactly the
pattern of distribution of the radioactive waste. In these
particular tanks the waste had aged almost 15 years and ac-
cordingly all the short life materials had decayed to insig-
nificant levels. The only radioactive nuclides left in
important levels were radioactive strontium and cesium. Of
course, we have other thanks in the same location which have
never developed leaks. The corrosion experts indicate that
the main problem is near the interface, between the liquid
and the vapor as far as corrosion is concerned. If a leak
develops it is likely to be due to a fine line crack and will
be sealed off by the chemical salts. The tanks will probably
leak near the liquid linp first and we would not loose very
many gallons of waste. In answer to the second part of this
question, regarding the disposal of waste into the soil, we
are fortunate at Hanford in having about 560 square miles of
area. In the area where our separation plants are located,
the ground water level is at 300 feet. The program is run
in such a way that when radioisotopes are detected in the
ground water, we avail ourselves of another soil column in
the near vicinity and we cease pumping wastes into this partic-

ular column, since the ion exchange capacity has been used up.
Most of the short-life material, of course, is decayed before
reaching the ground water.
Q: Has any attempt been made to adjust the pH of the waste
in order to take advantage of the ion exchange capacity
of the soil?
A: The optimum pH has a considerable range and for the most
part is on the basic side. There has been little need at
Hanford for adjusting the pH.

R. F. Foster*
Although radioactive wastes are often viewed as a kind
of pollution with worrisbme implications, many of the basic
considerations associated with the presence of radionuclides
in surface waters are not different from those which apply to
non-radioactive materials originating in many phases of our
industrial and agricultural economy. For a great variety of
toxic materials which are present in effluents, or in the
drainage from agricultural areas, we must recognize that it
will rarely be economically feasible to remove completely
every trace of the substance from the water regardless of our
desires to do so. We are faced, then, with the problem of
defining the maximum concentrations of many different kinds of
toxic substances which, after rational consideration, are
generally acceptable. It should be emphasized that the posture
on radioactive wastes has been substantially more conservative
than for most non-radioactive wastes since the objective has
been to restrict the release to the lowest practical level
rather than to utilize the capacity of the environment to the
In a consideration of the biological aspects of a broad
variety of toxic materials which may be present in the water,
we usually evaluate the potential effects of various concentra-
tions of the substance on (1) man from drinking the water,
(2) man from eating foodstuffs which have become contaminated
from the water (this is true not only of radioactive materials
but of disease organisms, insecticides, herbicides, carcinogens,
and many other compounds as well), (3) man from the use of the
water for swimming or other recreational or occupational purposes,
(4) valuable aquatic life either directly or through effects on
its food supply or habitat, (5) domestic animals and wildlife
which obtain the toxicants from the water or from contaminated
food, and (6) irrigated crops. Obviously, all of these facets of
the problem will not be equally restrictive in establishing a
maximum permissible concentration.
For a number of substances it may be sufficient to identify
the limiting case and proceed with control to a maximum permissible
*R. F. Foster, Biology Laboratory, Hanford Laboratories
Operation, General Electric Company, Richland, Washington.

limit on that basis. For other cases, including radioactive
materials, it will be necessary not only to identify the bio-
logical component which is most vulnerable but also to evaluate
and combine the exposures received by that component from a
variety of soutces. Particularly in the case of ionizing
radiation, we recognize that a single source of the radiation
may be of less interest than the combined dose received from
all sources including cosmic and other "environmental" radia-
tion, medical uses, and internally deposited emitters derived
from drinking water, foods, and air.
Although the dominant mechanism which leads to biological
damage from radioactive materials appears to be the ionization
produced in the tissue, this by no means signifies that all
radionuclides are similar in biological hazard. Major dif-
ferences arise because of vastly different amounts and kinds
of energy released, rates of radioactive decay, degrees of
uptake by organisms, tissue of deposition, and degree of
retention. Uptake and deposition are, of course, dependent
not upon the radiological characteristics of the nuclide but
upon the particular chemical element involved and its chemical
and physical state. Of the 92 natural elements ranging from
hydrogen to uranium there are over 700 radioactive isotopes.
At the present time about 200 of these have sufficient exposure
potential to warrant their inclusion in the National Bureau of
Standards Handbook 69 - the recommendations of the NCRP on
"Maximum Permissible Body Burdens and Maximum Permissible
Concentrations of Radionuclides in Air and Water for Occupa-
tional Exposure." Thirty-nine of the 200 have half-lives of
less than one day and 29 occur in nature.
If we direct our attention to those radionuclides which
have drawn some attention as observed or potential contaminants
of marine or aquatic organisms, the list would be restricted
to about two dozen at this time. Those which result from the
fissioning of uranium or plutonium are: Sr89 Sr^O-Y^O,
Y9! Zr95-Nb95( ^106.^156, J131, Cs137, Bal37m> Bal.u140f
Cel^-Prl^, and Pml47. Those which result from neutron
activation of stable elements are: (Na^), p32> Cr^l, Mn^^,
Fe55} Fe59, Co^^ Co^O, (Cu^),	, and (As^). (The
bracketed isotopes have half-lives of only a few hours.) Some
additions to this list can be expected as reactor fuels, cooling
systems, and hardware are modified in the future.
Those radionuclides which are potentially of biological
importance in environmental systems have the following

1.	They are created in sufficient amounts so that
accumulation by organisms is possible.
2.	Their half-lives are sufficiently long so that
they survive to the point of exposure.
3.	The energy released by their decay is sufficiently
strong to contribute significantly to the total
exposure dose.
4.	They are accumulated from the water so that
the concentration in the organism appreciably
exceeds the concentration in the water.
Not all of the isotopes in the above list possess all of
these characteristics. Experience to date would suggest that
only about a dozen of them can be classed as significant contami-
nants of aquatic systems. While we should not underrate the
potential biological significance of these, neither should we
arbitrarily conclude that substantial amounts of any kind of
radioactive material will be taken up by aquatic organisms.
The processes by which aquatic forms take up radioisotopes
from their environment are identical and coincidental with those
by which the stable isotopes of the same elements are taken up
from the environment. For example, if the concentration of stable
zinc is 5,000 times greater in an organism than in the surrounding
water, then we may anticipate that radiozinc in the water will
be concentrated by the organism to the same extent. The mechanisms
of uptake are adsorption onto exposed surfaces, direct absorp-
tion into the organism from the water, and ingestion of the
radionuclide with food.
Adsorption is of greatest significance in planktonic
forms with large surface-to-volume ratios and also occurs on
inert materials which may be ingested by filter or bottom feeding
species. Since chemical and physical binding forces are of
greater importance than physiological demand in this case, a
wider variety of radioelements is "fixed" by adsorption than
by the more selective biological processes.
Absorption is of greatest significance in the plant forms
which obtain all of their nutrients by this mechanism. It also
occurs in the animals, however, and is important in the uptake
of calcium and other ions by the gills of fish. The process is
selective for elements which are needed by the organism and
effectively concentrates the biologically essential materials

in lower forms which are subsequently eaten by higher animals,
including man.
Ingestion is the dominant means by which fish and other
aquatic animals acquire the materials essential for their growth
and metabolism. Because of selective uptake by the gut and
elimination of unnecessary materials by the kidneys, gills, etc.,
the biologically essential elements, including their radioisotopes,
are concentrated in appropriate tissues.
Since the chemical composition of different organisms
and different tissues varies greatly, the kinds and amounts of
radionuclides which are found in them will also vary. Field
observations in zones where mixtures of radioisotopes are
present have shown that ruthenium will be especially concentrated
by certain seaweeds, strontium by lobsters, iron by reef fish,
zinc by shellfish and ocean fish, cobalt by shellfish, and
phosphorus by all organisms. Because of the broad spectrum of
radioactive contaminants concentrated by plankton, it is considered
as one of the best "indicators" of the presence of radionuclides.
Although we may sometimes think of the uptake of radio-
nuclides by aquatic organisms from the water or through food
chains as a "one-way street" this is certainly not an accurate
concept. The relationship between the nuclides in the water and
in the biological forms might better be thought of as a complex
chemical exchange system in which there is a kind of equilibrium
established between the concentration of the nuclide in the water
and in the various biological forms, silt, and other exposed
surfaces. The rate of exchange between the water and the photo-
synthetic plants will often be quite rapid. A slower exchange
will occur between the various compartments of the community and
the vertebrates, especially if the radioelement is firmly deposited
in bone or scales. The bottom sediments will often contain an
appreciable fraction of the total inventory of the radionuclide.
Thus, in considering the capacity of the environment to accommodate
radioactive materials, we should include not only the volume of
the water, but also the mass of the biota and the sediments.
The accumulation of radionuclides by aquatic organisms
can affect radiation exposure considerations in the following
1. A major part of the exposure dose received by
the organism is apt to originate from the deposited

2.	The edible organisms, such as fish and
shellfish, can serve as vectors to funnel the
radionuclides to man.
3.	Concentration by massed organisms, particu-
larly algae, can increase the exposure dose to
persons nearby, e.g., algae growth on boats.
4.	The removal of the nuclides from the water
by the biota can aid in decontamination.
The volume of information amassed thus far on the effects
of ionizing radiation on aquatic organisms is very meager when
compared with that available on the more common species used
for laboratory experimentation. Nevertheless, a sufficient
block of information has been accumulated to permit several
generalizations. The lower or more primitive phylogenetic
forms are typically more resistant to ionizing radiation
than the vertebrates. In broad terms, fish can tolerate on
the order of twice the amount of radiation as man, and algae
several hundred times this amount. It must be recognized,
however, that within this broad generality, there are particu-
lar species and particular stages of development which are
hypersensitive. An important question, which is as yet
unresolved, is whether a complex ecological system might be
affected by lower doses of radiation than required to affect
individuals within the system.
It seems reasonable to anticipate that in a vast majority
of situations where some concern is expressed for the welfare
of aquatic organisms exposed to radioactive materials, some of
these organisms will be used as food either for man or for
domestic animals. The kinds and amounts of radioactive materials
present in the organisms must then be evaluated both on the basis
of potential radiation effect to the organisms and on the ac-
ceptability of the edible forms as food. Available information
points to the use of the organisms for food as being sub-
stantially more restrictive on the maximum permissible concentra-
tion of radionuclides in the water than the potential radiation
damage to the biota. Here again our knowledge is limited, however.
Pacjfc Northwast Water Laboratory
200 South 35tn Strest



Q: Where do migratory waterfowl appear on the chart regarding
the tolerance to radioactivity?
A: Presumably, it will be between man and fish, and that is
near the bottom, or point of lowest tolerance. Actually, man
should not appear on this chart. We are not interested in
killing man, but in protecting him from genetic damage. This
is where the permissible dose levels fall down. Naturally,
there will be different criteria established for fish and
other organisms than for man.
Q: In what terms are these units on the chart?
A: These are in terras of the total radiation dose or roentgens
of radiation in which the organism is placed in a field of
gamma radiation for a specified length of time.
Q: How much of the total radiation in the Columbia River is
due to Zn^5?
*5 )
A: It is of an order of magnitude less than P .
Q: Does it have any significance on fish as food for man?
A: If we look at the comparative intake rates of the several
isotopes, p32 amounts to about 957. plus. Zn^ is the next
most abundant isotope in the order of about 2%. Because of
the abundance of the P^2 versus the zinc and also because of
the fact that the permissible intake rate of Zn^5 is greater
than p32, the contribution which Zn*>5 makes to the total expos-
ures of the individual who is eating the fish puts this down
probably in the order of 1%.

Ely J. Weathersbee*
Curtiss M. Everts**
We are pleased to have this opportunity to present some
of the problems we have encountered in developing the radiological
health program in Oregon, and we hope that in the open discussions
that follow this presentation, we can count on some helpful suggestions
from those present. In an effort to avoid repetition and because
of the similarity of problems in the two states, the material to
be presented has been divided into two general areas; one of which
we will present, the other to be presented by Mr. Stockman of
Ever since the detonation of the first nuclear device, pol-
lution control administrators have wondered what effect the future
developments in nuclear energy might have on the quality of water
for which they are responsible. This curosity continued subsequent
to 1946 when the Atomic Energy Commission was established to place
atomic weapons under civilian control. It became even more evident
in 1954 with the adoption of the Atomic Energy Act of that year,
that if the development and regulation of peaceful uses of atomic
energy were to be undertaken, that state and local governments
would have to gain additional intelligence on the subject and
develop programs for local control.
While some of the more populated states were able to under-
take the development of programs and the training of personnel,
the states with small populations found it difficult to obtain funds
to initiate programs, particularly since the responsibility for
regulation apparently still rested with the Federal Government.
Despite these handicaps, however, state health agencies and state
water pollution control groups, cognizant of the problems that they
were to face in the future, began in at least a modest way to train
personnel and to assemble laboratory equipment in an effort to
gain a better knowledge of the problem and to initiate limited
surveillance programs.
~District Sanitary Engineer, Oregon State Board of Health
**Director, Division of Sanitation and Engineering, Oregon
State Board of Health.

In 1959 Congress amended the "Atoms for Peace" Act to permit
states to share the regulatory responsibility with the Atomic Energy
Commission whenever a state could show that they were capable of
carrying on such work effectively. Essentially, the criteria
under which a state may assume some of the regulatory authority
formerly exercised by the Atomic Energy Commission are as follows:
1.	A state must demonstrate a program (including laws,
regulations, personnel and facilities) capable of
adequately protecting the health and safety of the
2.	The State's program must be compatible with and essen-
tially the same as that of the Atomic Energy Commission.
It is the responsibility of the water pollution control
administrators to effectively manage the quality of all surface
and underground waters to the end that they may be used for bene-
ficial purposes. Surface waters must be preserved as sources of
domestic, industrial and agricultural water supplies, for the prop-
agation of fish and aquatic life, and for the recreational enjoy-
ment of the people.
Ground waters must be preserved for domestic, industrial
and agricultural water supplies. It is obvious, therefore, that
the discharge of waste containing radioactive materials into
either surface or underground waters would promptly become a
matter of concern to the pollution control administrator. In
the course of these events, standards establishing the maximum
permissable concentration of radioactive isotopes were in the
process of development, and while they have achieved a high degree
of acceptance among some scientists in the field, there are others,
and particularly the public, who may not agree with them until
they have been completely satisfied that the levels suggested
are absolutely safe.
The states began to adopt their own enabling legislation
and regulations after 1954 when the peaceful uses of atomic energy
were under more extensive development. The law in Oregon was
adopted in 1957. It named the State Board of Health as a regulatory
agency, established a five man advisory committee for the Board,
and directed the State Board of Health to promulgate regulations
on the subject of radiation protection after first making a two
year study of the problem. The present status of the Oregon program
is as follows:

L. The program is being directed within the State Board
of Health by a six man intradepartmental committee --
advised by the five man Advisory Committee as provided
by the 1957 statute.
2.	Regulations have been prepared, approved by the
Advisory Consnittee, and will be presented to the State
Board of Health for consideration for adoption at
their December meeting.
3.	Budget requests have been made for four staff positions
and approximately $13,000 for equipment for the 1961-
1962 biennium.
4.	A staff training program is being conducted within the
department and advantage is being taken of available
short course training to the greatest extent possible
without neglecting other duties.
5.	A member of the staff routinely accompanies Atomic
Energy Commission inspectors on their visits to licensed
installations within the State.
6.	The City of Portland and the State Fire Marshall are
kept currently advised of locations of Atomic Energy
Commission licensed installations.
7.	Our Air Pollution Control Section has participated in
both of the National Air Surveillance Networks since
the inception of these programs, and our laboratory
personnel have participated in the analytical reference
service program at every opportunity.
8.	A tentative environmental surveillance program has been
formulated and will be implemented immediately if our
budget requests are at all favorably treated.
9.	A request for funds from the Public Health Service
for a study project on the Columbia River has been
submitted and is currently under consideration by them.
Fe still have a few things that must be done such as:
1. Obtain changes in our Radiation Protection Law to permit
assumption by the State of regulatory duties from the
Atomic Energy Commission.

2.	Revise or supplement our regulations to provide for
licensing of radioisotope users and otherwise satisfy
Atomic Energy Commission criteria.
3.	Establish laboratory facilities, develop staff competency,
and implement the surveillance and regulatory programs.
In the accomplishment of these objectives we would naturally
anticipate that a great deal of correlation of activities would
be necessary between the various federal and state agencies who
have an interest in this field. In addition, local agencies such
as health departments, fire departments and others, may be expected
to develop a much keener interest in the subject. Certainly one
of the prime responsibilities of the state agencies would be to
keep these groups informed of its actions and procedures.
We have quite a way to go before we have an adequate and
complete program in operation in Oregon. However, we feel that
the situation is not so critical that we cannot meet the need
provided that we do not drag our feet from now on.
In summary -
We are in the early stages of a move from strict federal
control of radioactive sources to joint Federal - State - Local
regulation more in line with the usual handling of the more common-
place pollutants.
Our state program should eventually involve licensing, in-
spection, and enforcement of regulations, monitoring of the environ-
ment, coordination with federal and local activities, including
making available to them the information necessary to satisfy
their needs.
We would look to the Federal Government to maintain control
over reactors and other activities which could result in widespread
contamination, regulate ocean disposal of wastes, coordinate waste
disposal practices among the states, regulate interstate transpor-
tation of materials, provide consulting services to the states,
develop standards, and promote research.
Radioactivity is relatively new as a pollution problem requir-
ing speciall trained staff, special equipment, and "education" of
the public so as to keep the problem in its proper perspective --
(these are the areas to be covered by Mr. Stockman).

Robert L. Stockman*
The remarks prepared by Mr. Curtiss Everts and Mr. Jack
Weathersbee of the Oregon State Board of Health have dealt with
the Areas of Interest and Legal Aspects as they relate to the
problems of the administrator dealing with radioactive wastes.
In order to avoid duplication, I will not discuss these
areas except for incidental reference. My remarks will relate
largely to Recruitment and Training of Personnel, Laboratory
Resources, and Public Information.
In considering the problems of the administrator, it is
not possible, nor even practical, to separate the waste disposal
problem from the total problem of population exposure to ionizing
radiation for at least two reasons.
1.	Human exposure to any source, natural, or man-made,
is of concern.
2.	In order to effect the necessary control, all sources
will ultimately come under surveillance or cognizance.
In developing physical and personnel resources, program
criteria, and controls, the administrator will take into account
all sources of ionizing radiation, the occurrence and movement
of radioactive material in the environment, and then determine
the attention needed in each area. Broadly state, the areas of
concern would include medical, industrial, waste disposal, disaster,
weapons testing, and miscellaneous.
The question of research presents at least two important
questions to the administrators, as follows:
1. What is to be done? There is no doubt need for further
research in the areas of biological effects, methods of environmental
surveillance and investigation, and data evaluation which can be of
extreme importance to the improvement of radiation control programs.
*Mr. Robert L. Stockman is Engineer in Charge, Air Sanitation
& Radiation Control Section, Washington State Department of Health.

2. Who is to do it? Research work at the Federal and
private enterprise level is relatively well on its way. The
administrator at the state and local level does well at the
present time to keep abreast of what is going on. But, in look-
ing to the future, he must make a choice of waiting for develop-
ments nationally, supporting or cooperating in nation-wide
research, and supplementing these with his own research arm,
at least for special problems. If he is to maintain a research
arm, it may put a very different fiscal and organization com-
plexion on his program and call for specific additional needs
in equipment and personnel resources. It is likely that his
own research activities will be somewhat limited, but there is
no doubt that he should cooperate in nation-wide research activ-
ities and, where justified, support research activities.
With this background, let us look at a few of the specific
Recruitment and Training of Personnel
This presents perhaps the most difficult problem. While
the pool of trained people is growing, it is still more than a
fiscal problem in view of the relatively limited supply of
people. This is particularly true in the case of a state agency
which is usually in not too good a position in the competitive
Under this circumstance, while a state agency may hope-
fully recruit for experienced personnel, they will largely depend
upon recruiting younger personnel with a good potential and capable
of utilizing the training opportunities that can be offered. This
approach is not necessarily undesirable, but it does retard the
early development of needed programs. One experienced man could
enhance the progress to a very great extent, provided he has men
of good potential assigned to him. The problem then begins to
resolve itself to:
1.	The recruitment of men with good potential and the pro-
vision of training opportunities for them and
2.	The recruitment where possible and paralleling number 1,
of at least one experienceddperson.
If the program is to have any research activity, different
personnel needs occur. A research activity does not seem an
appropriate part of a control program in its initial years. This

is not to say chat a control agency should not stimulate, support,
or cooperate in research nor that it should not develop a research
arm as a second important program phase.
In general, the state	can look with some confidence to the
training resources available	from the A. E. C., the Public Health
Service, and institutions of	higher learning, and, by utilizing
them to the maximum, will be	fostering the development of a pool
of experienced personnel.
Laboratory Resources
From the fiscal standpoint, we get about what we pay for
as far as physical facilities are concerned. The cost of a facility
for environmental surveillance of radioactivity may easily range
from $2000 to $100,000 depending upon the objectives and sophistication
of the program. The effectiveness of the laboratory, however, is
entirely dependent upon the quality of personnel assigned and the
two cannot be separated.
In planning for the future, the administrator must look
very closely at the needs, the objectives, and the physical prob-
lems. There seems little question as to need and objective in the
broad sense in that there will undoubtedly be more, rather than
less, environmental surveillance in connection with control pro-
grams and that the evaluation will require more refinement as to
types, transport, and concentration of radioactivity. This,
then, leads to projecting criteria for the physical laboratory
needs. First is the laboratory space as to size and location.
One would be most fortunate to be in the unlikely situation of
being able to place a facility of any permanency in existing lab-
oratory space or in remodeled office space. The requirements for
basic utilities (plumbing, wiring, ventilation, and air condition-
ing) shielding, sample preparation requirements, and room for
expansion are cause for very serious consideration in making an
early decision as to location. Second is the problem of program-
ming the purchase of specialized equipment. This should be done
with considerable caution considering the needs and capabilities
of the laboratory in any given time, the integration of component
items in a scheduled purchasing program, the capability of equipment
maintenance, and caution as to the problem of obsolescence that
may result from over-purchasing.
Some consideration should be given to space requirements
for potential research activities, but, again, this will not
usually be an early part of the program.

Considering the two problems of personnel and laboratory
resources together, we might look at an example. Appendix I
shows the approximate sampling schedule and reflects the capability
of the laboratory recently completed by the California State
Department of Public Health. This would not appear to be a large
scale program although, relatively speaking, it is larger than
most states have to date. Water and sewage represent less than
10% of the environmental sampling to be done. As we move from
the gross beta and alpha capability to the strontium-90 and gamma
scan capabilities, basic space and equipment requirements can easily
increase tenfold. To accomplish the schedule indicated in the
table, required expenditures for equipment of $63,000; for basic
laboratory space, including hoods, benches, and utilities, $42,000
and for personnel (1 year) $83,000, or a total of $188,000 for the
first year's operation. To most state agencies this would appear
to be a tremendous sum and yet it is fairly conservative after
careful examination. Basic equipment includes automatic low-
background G-M detector for strontium-90, window-less gas flow
proportional counting for gross alpha or beta, single channel
gamma analyzer and scintillation well crystal for single gamma
emitters, and a 256-channel analyzer with 6-ton steel shield and
4x4 scintillation crystal for unknown gamma mixtures. Personnel
include 8 chemists, one instrument technician, 3 laboratory assist-
ants, and two clerks.
Such a program may not be necessary in some locations but
may be more than justified in others. This is a decision which
the administrator will have a large part in making. Suffice it
to say, however, that short of a legislative windfall, careful
fiscal planning is required. The utilization of outside resources
may be particularly important, at least in the early stages.
These would include the laboratory resources and training oppor-
tunities potentially available from the A. E. C., from the Public
Health Service Taft Sanitary Engineering Center, and the Southwest
Radiological Health Facility, and institutions of higher learning.
In any event, the states will begin to move in the collection
of environmental surveillance information. The results of research
could be helpful here to provide improvements in surveillance, tech-
niques, and equipment and methods. Particularly important might be
the development of isotopic indicators for specific situations. For
example, in the case of Hanford discharges to the Columbia River,
it would be most helpful if analyses for a limited number of specific
isotopes might be found to provide sufficient information for routine
purposes as to the presence and concentration of other isotopes. The
evaluation of the collected data will be a logical objective and here
further research in the transport, uptake, and effect of radioactivity
would be most helpful.

Public Information
The problem of public information is not unique to the
radiation area but can have very dramatic repercussions. In
general, the administrator would like to be in a position to
reassure the public. Sometimes he can do this on the basis of
reasonable judgment factors in the absence of specific data,
but he would be much better off if properly equipped with in-
formation. There are several areas in the problem as follows:
1.	Public information related to a major Atomic Energy
installation, existing or planned. Here he must be equipped
with information as to the nature of the installation, the
beneficial use involved, and the degree of probable hazard.
He should be in a position to determine and state that the
probable hazard is minimal, or that it is sufficient to require
preventive or corrective action. He will be involved with an
interested public on the one hand or an aroused public on the
2.	Radiation incidents or disasters. We all know how
the public can react to any rumor relating to an incident. We
have had several episodes in Washington which involved rumor
of the presence of radioactive material, rumor of the spread
of radioactivity into public areas, and rumor of actual radiation
injury. Fortunately, the facts were not as rumored, but rumor
is much more difficult than fact in handling the public infor-
mation. Fortunately, with careful handling through the news
media, the situations were adequately handled, but had come
very close to serious public alarm. The administrator then
must be prepared not only for the rumor problem, but for proper
public information in the event of an actual incident.
3.	General information. As the uses of radiation increase
in number and variety, it is well to maintain a continuing program
of information to the public about these uses, the probability or
lack of probability of hazards, and the control to prevent hazards.
A proper conditioning of the public in this manner should do much
eventually to offset public information problems associated with
1 and 2.
Let's look at an example of a potential public information
problem in our area. The fact that radioactivity has been found
in shellfish would make an interesting news story. Should this
happen without adequate explanation by responsible authorities,
needless emotional outburst and probable economic injury due to
buyer resistance could result. I merely place the questions here,

"How well prepared are we to handle such a problem?"; "Do we have
sufficient factual information to make an authoritative statement,
or must we act on general assumptions which we hope are reasonable?"
The fact that there has been a minimum of concern among the local
population in the Hanford vicinity is in part a credit to public
information activities and in part, I am sure, due to the tact
that the population has grown up with the installation since its
early days. But, supposing we were to go in now to make a
rather thorough study of the occurrence of effects from radiation
in that local population. It appears to me that this is one of
the most likely places in the world to make such a study. Here
is a sizeable resident population exposed to radiation over a
long period at environmental levels which could be fairly well
estimated. I believe such a study should be made as one of
great national interest. The public information aspects of such
an effort would be one of its most important elements. Here we
have a population group long conditioned to the thought that
there is no hazard, suddenly being asked to serve as laboratory
objects. I am sure that it can be done, but it must be very
carefully handled.
In summary, the states have a continually increasing role
in the control of radiation as it affects the public health and
welfare. They will have increasing legal responsibilities in
addition to their existing moral responsibilities. They will
be interested in all sources of radiation exposure, one part of
which has to do with activity in our water courses as a segment
of the environment. The administrator faces problems which are
challenging but not insurmountable. Among these are the problems
of personnel recruitment and training, the development of laboratory
and other physical resources, and a very important one in public
'information. The results of past and continuing research will
have a bearing on the objectives and means of accomplishing his
program. In the early stages, a development of his own research
arm is not likely, but it is important that he follow research
efforts, suggest research needs and support or cooperate in
research. Ultimately, he may develop research activities to meet
the needs of certain of his program areas.

Q: How do you expect to train your staff in the radiation
field? Do you propose to send them to universities and
A: Yes, we have done this traditionally in other areas of
our operation. Training will be accomplished by means of a
combination of formal graduate training and short courses,
and by placing men in in-service training in such places as
Hanford, Las Vegas and the Center. At the University of
Washington the Department of Biology has a summer institute
for this type of training under a National Science Foundation
Q: Do you have any idea regarding the amount of trained
personnel in this field in Washington? How many trained
teachers are there7
A: Probably, outside of captivity, there aren't very many.
Because of the presence of Hanford, there are probably more
people of this type in Washington than in any other state in
the country. We have several people in the medical radiation
field. Practically none in private industry or public activity
outside of institutions of higher learning.
Q: Is it possible that the states may choose to have more
restrictive regulations than those set forth by the Atomic
Energy Commission or the Public Health Service? If so,
is there any conflict here'
A: There should be no conflict. However, it would be rather
inappropriate for a state to go into the waste phase without
going into the whole radiation field. The waste disposal
problem is a comparatively small part of the total program.
Q: In the State of California, the State thought that the
disposal of wastes at 1,000 fathoms (required by AEC) in
the ocean was not deep enough, and went to 2,000. What
would be your reaction to this7

A: We have not faced this problem in the State of Washington,
since we have no formal contractors for the disposal of radio-
active wastes into the sea. The selection of 1,000 fathoms
was arbitrary, and no doubt the deeper the better.

Allyn Seymour*
Ideas for the future use of nuclear detonations for
peaceful purposes are being studied by the U. S. Atomic Energy
Commission. The program is known as Plowshare, of which one
part is Project Chariot. The various projects in the Plowshare
program are typical of ways in which nuclear explosives may be
used in the future. At the present time a moratorium at the
request of our government prohibits the detonation of nuclear
devices for any purpose.
The Plowshare projects in general are underground ex-
plosions in which none or only part of the radioisotopes
that are produced escapes to the atmosphere. As a consequence
the question arises, "What will be the contribution to the
radioactivity in our environment by nuclear detonations for
peaceful purposes?" or as the biologist might ask, "What will
be the biological cost?". The following discussion will not
provide specific answers to these questions but will explain
the types of projects that are envisioned, especially Project
Chariot, and in this way partially answer these questions in
a general way.
The Lawrence Radiation Laboratory at Livermore,
California initiated the Plowshare Program and as early as
February 1957 a symposium was convened there to discuss ways
in which nuclear explosions could be used for other than
military purposes. The name, Plowshare, was suggested by
the passage in the Bible that reads, "	 and they shall
best their swords into plowshares, and their spears into
pruning hooks; 	" (Isaiah 2:4).
In considering projects that might be suitable for the
Plowshare program it was recognized that nuclear explosives
differ from chemical explosives in that they are big and that
they produce radioisotopes. The great size of the nuclear ex-
plosives meant that primary consideration was to be given to
projects that would be larger than the largest projects in the
past with chemical explosives, for example greater than the 1300
tons of TNT used to remove Ripple Rock in Seymour Narrows,
*Allyn H. Seymour, Associate Director, Laboratory of
Radiation Biology, University of Washington, Seattle, Washington.

British Columbia. The problems created by the production of
radioisotopes can not be eliminated but can be minimized by
the use of a "clean" device, that is, one in which the ratio
of fusion to fission is high, and by containing the radioiso-
topes underground. With these considerations in mind projects
in the following categories have been suggested:
1.	Civil engineering. Large volumes of earth and rock
can be moved with nuclear explosives at costs below those of
conventional methods. For detonations in which the yield is
about 2 kilotons or less the use of high explosives is cheaper,
but at 10 and 100 kiloton yields nuclear explosives are
cheaper by a factor of about 3 and 25 respectively (Griggs
and Press, 1960). Projects to be considered in this category
include the excavation for a harbor, the digging of a canal
or the removal of a navigational hazard.
2.	Oil recovery. Three methods have been suggested.
a.	Tar sands. The oil in tar sands, a mixture
of sand and crude oil, cannot be extracted by conventional
techniques. It is believed that the heat released by nuclear
explosives will lower the viscosity of the oil in the sands
sufficiently to permit recovery by conventional means.
b.	Oil shales. By fracturing oil-bearing
shales oil can be released or recovered by in-place heating
followed by pumping.
c.	Secondary recovery. Most oil fields, when
depleted by conventional recovery techniques, still contain
appreciable quantities of oil. Heat and blast effects from a
nuclear explosion could be utilized in secondary recovery of
this oil.
3.	Power and Isotope production. The energy released
and trapped by fully contained nuclear explosions offers a
possibility for use in both power and radioisotope production.
The heat produced by the explosion would be contained under-
ground and released in a controlled manner by use of a trans-
fer agent such as water, carbon dioxide or nitrogen, and used
either directly or in the production of electric power. At
the same time an appropriate substance placed near the deto-
nation would be bombarded by neutrons and in this way produce
4.	Mining. After the fracture of low-grade or inac-
cessible ore deposits, or deposits where the hardness of the

rock makes the use of high explosives uneconomical, minerals
would be recovered by leaching in place or other conventional
mining methods.
5.	Water resources. Possibilities in this category
include regulation of underground flow of water, water
storage and the production of fresh water from sea water by
utilizing the heat produced in an underground explosion.
6.	Scientific uses.
a.	Seismology. Controlled nuclear explosions
may improve one hundredfold the information that is needed
to determine the earth's structure.
b.	Physics. If neutron-rich isotopes of element
102 and heavier are to be made, the job probably will be
accomplished by using a thermonuclear explosion as the neutron
source (Cowan, 1959).
c.	Meteorology. Nuclear explosives are not
likely to be used to control weather but might have some
influence on a specific storm.
Of the projects listed above some are impractical at the
present time. However, for two, some studies are currently
under way. "They are: Project Gnome which is a proposed deto-
nation of a 10-kiloton device in the salt beds near Carlsbad,
New Mexico, for the purpose of investigating the feasibility
of recovering power and isotopes, and Project Chariot which is
a proposed experiment to use two 200-kiloton and three 20-
kiloton devices to demonstrate the feasibility of excavation
for such purposes as harbors and canals. In addition, there
have been discussions with the petroleum industry regarding its
interest in supporting an AEC-U.S. Bureau of Mines project to
investigate the practicability of using nuclear devices to
crush oil shales thereby permitting the recovery of oil by in
situ retorting	Thorough consideration is being given
to every phase of these projects and the Commission requires
that every precaution be taken to assure the public health and
safety." (Shute, 1959).
The Gnome detonation will be contained entirely under-
ground without release of energy or radioactivity to the
atmosphere, whereas the devices for the Chariot Project will be
so placed that the surface above the devices will be excavated.
The excavation will not extend to the depth at which the de-

vices are placed but will allow the escape of a small part
of the radioisotopes that are produced. Kinds and amounts
of radioisotopes to be expected from Chariot can be predicted
by extrapolation from data obtained from the detonation of
small underground devices In Nevada; however, one of the
objectives of the Project Is to obtain information from which
the accuracy of these predictions can be Improved.
The site of the proposed excavation Is on the northwest
coast of Alaska below Cape Thompson at the mouth of Ogotoruk
Creek. The simultaneous detonation of the five devices would
produce an excavation with a basin about 550 by 900 yards and
a channel about 250 by 600 yards that would be accessible to
the Arctic Ocean. Minimum depth would be about 30 feet.
(A recent change in the devices to be used from two 200-KT
and three 20-KT to one 200-KT and four 20-KT devices will
8lightly alter these dimensions). The smaller devices would
be burled at a depth of about 400 feet and the larger at 700
The phenomena that occur when the devices are detonated
(called the phenomenology of underground explosions) can be
explained by associating the occurrence of various phenomena
with time-periods. The Rainier event (a part of Operation
Plumbob in Nevada in 1957), in which 1.7 kilotons of energy
were released In a room 6 feet square, 7 feet high, and 800
feet below the surface of the earth will be used as an example.
There are four major time-periods:
"a. Nuclear Phase (Microseconds). The energy of the
nuclear explosive Is generated in a few tenths of a microsecond,
vaporizing the assembly materials and forming a rapidly growing
fireball. The material in the Rainier room reached a temperature
of ten million degrees Fahrenheit and a pressure of seven
million atmospheres.
b.	Hydrodynamic Phase (Milliseconds). A shock wave
proceeds outward vaporizing, melting, and crushing the sur-
rounding medium. A cavity is formed by the outward motion of
the rock near the center of the explosion. In Rainier, the
shock vaporized a 3-foot thickness of rock (about 100 tons),
melted 7 more feet (about 600 tons), and crushed rock out to
130 feet. The cavity in Rainier reached Its final radius of
55 feet in about a hundred milliseconds.
c.	Quasi-static Phase (Seconds to Minutes). The cavity
cools and collapses when the internal pressure can no longer
support it. In Rainier, the pressure dropped to forty at-

mospheres In about a minute. A fissure must then have opened,
allowing the gases to escape and releasing the internal pres-
sure; the roof caved in and a chimney of rubble was formed.
About two hundred thousand tons of broken rock were produced.
d. Long-term Phase (Days to Years). A slow transport
of heat through the rock takes place, and the radioactive
products decay. In Rainier, the water present in the rock (20%
by weight) vaporized and distributed the heat over a large
volume; the highest temperature now present is at the boiling
point of water." (Johnson, 1959).
During the nuclear phase radioisotopes are created by
fission of the fuel material and by the capture of neutrons by
stable isotopes in the assembly materials and in rocks within
a meter or so of the detonation point. Therefore, the kinds
and amounts of various nuclides produced by underground ex-
plosions are determined by the kind of explosive (i.e. all
fission, or part fission and part fusion), and by the compo-
sition of the rocks (and assembly materials) immediately
adjacent to the detonation point.
Most of the radioisotopes are trapped in the fused
material formed by melting rock during the period the cavity
is enlarging (hydrodynamic phase). This is explained by
Hlggins (1960) to happen In the following manner. "When
the temperature of the gas reaches the condensation point of
some rock constituent, say about 4000 K for a rock containing
CaO, that constituent begins to condense into a liquid and
scavenges the gas phase of all radioactive species which have
equal or higher condensation temperatures. This condensed
material forms into droplets and mixes with material melting
on the wall surfaces. As lower and lower temperatures are
attained, more and more radioactive species condense into the
liquid phase."
The radioactive species that do not condense at the
melting point of rock and remain in the gas state migrate
through fissures that form during the quasi-static phase and,
except for the noble gas fission products Kr and Xe and for
tritium (if present), condense on all of the available sur-
faces. Hence radioisotopes from underground detonations may
be found in the fused material, on the surface of fissures
and broken fragments or in the permanent gas phase.
90	117
The precursors of biologically important Sr and CsiJ
are 33-second Kr and 3.8-mlnute Xe"^, respectively. Because
the half lives of the precursors are short the amount of

Sr^O and Cs^37 that escapes, or, conversely, the amount that
is contained in the fused material depends upon the length of
time the cavity stands before collapse. If the cavity
collapses one second after the explosion, about 20 percent of
the total radioactivity is in fused material, 70 percent in
the broken rock and on fissure surfaces, and 10 percent in
the permanent gas phase. If the cavity collapses 30 days
following the explosion the values are 85 percent, 5 percent
and 10 percent respectively. In the first case, most of the
isotopes that have rare gas precursors, such as Sr and Cs*"^,
would escape or be on the broken rock surfaces; in the second
case, most of the Sr^ and C8^7 would be Incorporated in the
With all or most of the radioactivity remaining under-
ground the question arises, "Does the ground water become
contaminated?" The answer is that it does only slightly,
except for tritium. There are three reasons for this con-
dition. First, the bulk of the activity is bonded In an
insoluble, unleachable glass; second, the ion-exchange property
of the rock ultimately removes the radioisotopes from the
water. When water comes In contact with contaminated rocks,
small portions of each remaining radionuclide enter the water
solution. However, the radioactivity which enters the water
is transferred to other rocks as the water moves into an
uncontamlnated region. An exception is tritium (produced by
thermonuclear explosions), which will move more or less with
the percolating water. And third, the detonation produces
a zone of finely-divided, unclassified material which acts as
an impermeable barrier to water flow. Expressed In percentages,
the insolubility accounts for removing about 90 percent from
availability, ion exchange removes more than 99 percent of the
remaining 10 percent, and the water distribution probably
removes 60 percent of the remaining 0.1 percent for each zone
traversed. In short, within a few feet all of the radioactivity
is absorbed on the mineral. (Hlgglns, 1959).
Higgins (1960) also has summarized the effects of
radioactivity upon other Plowshare projects. "The amount of
radioactivity which would contaminate an ore zone if It were
in the collapse region can be estimated, and is found to be
very small. Human occupations in such an ore zone should not
be restricted after the explosion, and the only detriment to
product values might be their technical contamination. (Con-
tamination which would preclude using copper in camera parts
or silver in making photograph film emulsion). None of the
properties of either petroleum products or the explosives
produced radioactivities indicate that petroleum would be

contaminated if nuclear explosives were utilized at some
step in their recovery. Use of thermonuclear explosives in
the development of water resources should be approached with
great caution because of the possibility of tritium contami-
nation, however, the fission products and induced activities
will not lead to contamination problems in regions where the
earth minerals have normal adsorption properties and water
flow velocities are not abnormally large."
In conclusion, present predictions about the Chariot
Project are summarized. The simultaneous detonation of four
20-KT devices at a depth of 400 feet and one 200-KT device at
700 feet is expected to make an excavation about 3/4 of a
mile long, 1/7 to 1/3 of a mile wide and, a minimum of 30
feet deep. Five percent of the radioactivity produced is ex-
pected to escape. Isotopes with gaseous precursors such as
Sr^O and Csl37 will predominate. Upon reaching the surface
some radioactivity should adhere to large particles that have
been thrown into the air and fall out relatively close to the
site of detonation. There would be little or no contamination
of the ground water unless tritium were present. The radio-
isotopes present in the insoluble, fused material and on the
crushed rocks would be the usual fission products plus the
Induced radioisotopes produced from the materials and rocks
surrounding the device.
In order to determine the "biological cost" of the
Chariot Project a full-scale ecological program has been
initiated under the direction of Dr. J. N. Wolfe, Division
of Biology and Medicine, U. S. Atomic Energy Commission.
There are 23 parts to the program and it probably represents
the greatest concentration of effort at any place or any time
on an ecological problem. After two years of work on the
program it would now be possible to compare conditions "before"
the event with what they might be "after" the event, in case
approval is granted for completion of the Chariot Project.

Q: How long after the detonation will they be able to move In
with ships and use the harbor?
A: You can go in the first day, if you want to stay a short
period; the second day, a longer period. For commercial purposes
I believe a week or two weeks would be perfectly safe.
Q: Do you have any ideas regarding the effect of the tremendous
heat on the permafrost, especially as it may affect the
construction of docks and piers and other facilities?
A: We have soil people who are studying the various aspects of
the soil movement and the effect of heat. The people at Ohio
State Agriculture Station have the major responsibility in that
area. We do not expect any difficulties with foundations for

W. J. Kaufman*
Radioactive tracers afford the hydraulic and sanitary
engineer a potentially valuable tool for the investigation of
a wide variety of natural phenomena involving the movement of
water, the transport of sediment, and the dispersion of waste
materials in the hydrosphere. As is often the case with a
new tool, a period of trial is required to establish both the
areas where application may be advantageous and situations
where disadvantages preclude beneficial use. Prejudice has
worked both for and against the full development of radio-
active tracer methodologies. Early scientific experiences,
often overly publicized in the popular and scientific press,
led many to the impression that here was the panacea to all
problems. As a consequence, great expectations were held,
only to be shattered as the attempts to reach solutions with
tracers progressed to their partially successful conclusions.
Three of the greatest obstacles have been cost, technical
complexity, and apprehension regarding the health and safety
problem. As the regulatory aspects of radiation control
leave the Atomic Energy Commission's jurisdiction and become
shared and dispersed among a host of state and local agencies,
we may expect the additional obstacle of red-tape frustration
to enter the scene.
In what ways may tracer applications lead to a better
understanding of hydrologic phenomena? By labeling a mass of
water or silt, without modifying its physical or chemical
properties, it becomes possible to directly observe its move-
ment in both space and time and, in effect, to distinguish one
otherwise identical unit of the labeled material from all
other material. The mixing or dispersing reactions occurring
in natural surface or ground water bodies are often too complex
to be amenable to analytic formulation, and the construction
of physical or analog models may not be economically or tech-
nically feasible. However, by the application of tracers we
may directly observe the phenomenon of interest in the full
scale system. In conducting such studies it is often possible
to employ natural tracers, such as the differences in
*W. J. Kaufman, Associate Professor of Sanitary Engi-
neering, Division of Hydraulic and Sanitary Engineering,
University of California, Berkeley.

chlorinity or the presence of a particular chemical constit-
uent, or to use added chemicals or dyes, with little special
advantage accruing from the application of a radionuclide.
In such instances, only a full knowledge of the problem can
lead to the most suitable tracer selection. It should be
emphasized that the application of tracers, either radio-
active or stable, generally does not simplify the problem
analysis, but rather requires a far more sophisticated
appreciation of pertinent physical and chemical relation-
ships .
Criteria in Tracer Selection
The selection of the most suitable tracer for a particu-
lar investigation entails the consideration of a great many
factors. These factors have been listed in three categories:
1.	Physical and Chemical Integrity. The tracer
selected should faithfully follow the medium it has been
employed to trace, without influencing the movement in any
way. For example, the introduction of several hundred pounds
of sodium chloride into a well to follow underground water
movements may create density gradients completely distorting
the phenomenon under study. On the other hand, many of the
radionuclides, though of such negligible mass they will not
influence the passage of water through a porous stratum, may
undergo chromatographic separation on natural ion exchangers
and move at velocities far less than that of water. Certain
chemical tracers, nitrate for example, may undergo decomposi-
tion and pass undetected by the chemical test intended for
their measurement.
2.	Acceptable Hazard. It must be admitted that the
radioactive tracer will represent a greater risk to the
investigator and the public than will most chemical tracers.
It must also be accepted that current research strongly
supports the thesis that even very small radiation exposures
are not beneficial and very probably harmful, though to a
small and unmeasurable degree. Where the application could
conceivably incur some small exposure to the public at large,
the investigator may be required to justify this exposure
in terms of the benefits expected to accrue from his investi-
gation. Such a justification may find little concensus at a
public hearing and the pressure of adverse public relations
may often deter management from employing radioactive tracers
in offsite studies.

3. Cost of a Tracer and Its Measurement. The cost of
a tracer, be it radioactive or stable, cannot be separated
from the effort, both technical and monetary, to quantitatively
determine its presence. A costly tracer may be quite satis-
factory, providing it can be readily measured at extremely
low concentrations with relatively inexpensive instrumentation
and a low cost per analysis. Continuous measurements iji situ
are often desirable and less costly than sampling combined
with laboratory determinations. Such measurements are feasible
with gamma emitting radioisotopes and commercial equipment;
but not so with such sensitive chemical tracers as fluorescein
or spent sulfite liquor solids (Orzan). A comparison of two
of the more satisfactory chemical tracers and tritium was made
by Pearson (1) and is given in Table 1. It is interesting
to note that the cost of tritium expressed on a weight basis
is nearly 10 million dollars per pound, yet the cost of tritium
required to label a million cubic feet of water is only 10
cents, less than that for either of the chemical tracers.
Amount Reqd.
for Tagging
106 ft3
28 mc
Liquid Scintil-

lation Counter

0.1 ppm
6.24 lbs


0.04 ppm
2.50 lbs


*After Pearson (I)
A few examples of specific tracing situations will
serve to further our understanding of selection criteria.
The problem of tracing water through the earth, particularly
through strata containing clays or organic matter, places a
very severe restriction on the list of completely satisfactory
tracers. All of the cationic tracers, including the radio-
isotopes, would be unsatisfactory due to the high degree of
sorptive loss that must be expected. Furthermore, almost all

elements or compounds exhibiting any significant polarity,
either positive or negative, and introduced in small concen-
trations, are likely to experience some adsorption which may
delay and modify the tracer arrival pattern at a distant
observation point. For example, radioiodine introduced as
the iodide ion is readily adsorbed by natural soils and thus
will not correctly depict the passage of water. The addition
of carrier iodide, i.e., iodine in the form of the stable
salt, will reduce the degree of sorptive loss, but also
increase the investigation costs. Where waters naturally
containing iodine are employed, as might be the case in well-
field brines, the carrier addition may be unnecessary since
many brines contain appreciable concentrations of the iodide
ion. Of all the currently available radioisotopes, tritium
(hydrogen-3), in the form of tritiated water, appears to mo6t
closely meet all criteria as the ideal ground water tracer.
However, one can conceive of situations, flow through limestone
solution channels for example, where fluorescein or other dyes
may be quite satisfactory, since the adsorption limitation
would probably be absent.
If various potential tracers were being examined as
labels for clay sediments, the chemical criterium regarding
adsorption would, of course, be almost diametrically opposite
to that for water tracers. Krone (2) has shown gold-198 and
scandium-46 to be almost permanently fixed to the sediments
of San Francisco Bay, even after prolonged contact with sea
water. Ellis (3) has reported quite similar results in studies
in the Sidney Harbor, Australia. Paradoxically, Hull and
Macomber (4) have successfully employed radiogold as a water
tracer for stream gauging with relatively little sorption
loss. In the presence of suspended material in the course
of deposition by a change in stream regimen, gold would
probably prove unsatisfactory as a water tracer and perhaps
tritium would be the only entirely satisfactory isotope.
The Problem of Measurement
Probably all radioisotopes conceivably suitable for
hydrologic investigations will emit either beta radiation or
beta and gamma radiation simultaneously. Since beta radiation,
even the more energetic radiation from such radioisotopes as
yttrium-90, has a range in water of no more than one centimeter,
a beta detector placed in a water labeled with a beta emitter
will "see" only a very small volume. To some extent, this
disadvantage of the beta emitter may be overcome by evaporating
a large sample of water and analyzing the dried radioactive

residue in an internal proportional detector especially
designed for this purpose. This procedure has the disad-
vantage of requiring greater laboratory technician time.
On the other hand, the employment of a gamma emitting
radioisotope and a gamma sensitive detector permits the in
situ measurement of a relatively large sample, since the
tenth value thickness of water*, including build-up, for a
one Mev gamma source is in the order of 100 cm. These
various aspects of the sensitivity of a radiation measure-
ment system may be expressed in terms of a "Minimum
Detectable Activity Concentration" (5) as defined by
equation (1)
in which E is the detection efficiency as a per cent, v is the
volume of the observed sample in milliliter, n^ is the instru-
ment background in cpm, and t is the interval of measurement
in minutes. A concentration of radioactive material as
defined by equation (1) would equal that just detectable at
a 95 per cent confidence level.
Several tracers and their respective measurement systems
are compared in Table 2 in terms of M.D.A.C. and the counting
rate observed per unit of radioisotope concentration. The
data are not strictly comparable since the counting geometries
are not identical for all measurements. The tritium data are
based on a laboratory measurement of a 32 ml water sample.
The remaining values are based on measurements with sensitive
probes placed in various containers, including containers suf-
ficiently large to comprise an "infinite volume". By way of
comparison, if an internal proportional detector were used
to measure cesium-134, it would be necessary to evaporate
approximately 15,000 ml of water to achieve a 10 minute counting
sensitivity corresponding to an M.D.A.C. of 0.016 /ipc/ml. Such
an observation would depend on the measurement of the beta
radiation of the dried cesium-134 deposit. Thus, it is amply
evident that from a sensitivity of measurement standpoint,
tritium is the least satisfactory of the tracers listed and
that gamma emitting radioisotopes have a very appreciable ad-
*The thickness of water required to attenuate ganma
dose rate by 90 per cent.
M.D.A.C. (jic/ml) = 9.0 x 10"^ nh

vantage over beta emitters. Furthermore, the in situ measure-
ment of gamma radiation has a special advantage in studies of
dispersion in lake and estuarine waters where a moving probe
may feed into a ratemeter and strip-chart recorder for continuous
radioactivity measurements. However, under these circumstances,
the M.D.A.C. values in Table 2 are overly optimistic and
should probably be increased by a factor of 10. As noted
earlier, an overriding consideration must, of course, be the
physical and chemical integrity of the tracer, a criterion
that may lead to the selection of some "less detectable"
Health and Safety Considerations
The hazard to the public of a water tracer is most often
judged in terms of the Maximum Permissible Concentration in
drinking water, since the domestic water supply would represent
the most likely avenue of exposure associated with a tracer
study. It is conceivable that under some circumstance
absorption of the tracer by edible fish might lead to significant
human exposure; but the likelihood of this occurring appears
most remote. Similarly, the adsorption on mud on which humans
might subsequently walk appears equally improbable. The isotopes
listed in Table 2 are shown in Table 3, together with their
half-lives, characteristic radiations, current M.P.C. values,
the latter reported by the A.E.C. in January 1960(7). In the
last column of Table 3, the ratio of M.P.C. to minimum reported
M.D.A.C. has been tabulated to indicate a "relative factor of
safety" at comparable experimental accuracy. One of the ad-
vantages of tritium becomes apparent, i.e., its low hazard, and
tritium, gold, and bromine are seen to have nearly comparable
capabilities if compared on the basis of equivalent hazard and
detection sensitivity.
Table 2 -- see following page.

- ^

t = 0.5 min.
t - 10 min.
Liquid Scintillation
Spectrometer. 32 ml
HTO Sample
5 G.M. tubes in 12 in.
wide x 7 in. deep chan-
2 in. dia. Nal crystal
in 12 in. x 7 in. chan-
2 in. dia. Nal crystal
in. 3 ft. dia. x 2 ft.
deep container. Spec-
trometer used
(Hull, (4)
4 G.M. tubes in infinite
vol. water
(after Ljungg-
ren (6)
1.5 in. dia. Nal crys-
tal in infinite vol.
Cesium-134 (4)
4 G.M. tubes in infin-
ite vol. water

Radiation Energies, Mev

12.46 yr
8.14 d
0.608 (87.2%)
0.335 (9.3%)
0.250 (2.8%)
2.69 d
35.9 hr
0.547 to 1.312
2.3 yr
0.648 (75%)
0.561 to 0.794
*Ref (7), Appendix B, Table 2
The longer half-life of tritium can prove of both advantage and
disadvantage, depending on the circumstances of application.
An example may serve to illustrate an approach to estimating
the biological risk of conducting tracer studies. It has been
proposed that a tracer study be conducted of the ground water
artificially recharged into the San Gabriel Valley of southern
California. Various objectives of the study include that of
identifying the beneficiaries of the recharge program and deter-
mining the fraction of the water recovered. (8) Since the investi-
gation involved long-term underground tracing, tritium was
selected as the only suitable radioisotope. It was proposed that
500 curies of tritium be diluted in a flow of 40 cfs over a period
of 35 days, so as to uniformly label 825 million gallons of water
with a tritium concentration of 160 ppc/ml, about 5 per cent of
the lifetime M.P.C. (Table 3).
Accepting the value of 10 days of life-span shortening per
roentgen exposure, and making additional assumptions regarding
water use, one finds the total biological "risk" to the present
population is about 2,500 man days. In an affected population of
100,000 persons, the individual risk would be about 0.6 hours.

By similar, but more tenuous computation, the total genetic
risk may be estimated at 5,900 man-days for a total biological
"risk" of 8400 man-days. These are average values, but since
the maximum risk to any individual was estimated to be about
4 hours, the average values are a reasonable basis of analysis.
What normal activity of man incurs a risk comparable to 0.6
hours? Jones (9) has computed the life shortening effects
associated with the normal characteristics and habits of man.
As typical of these, city versus country dwelling results
in 5 years of life-span shortening, a package of cigarettes
per day exacts a cost of 9 years, and the motor vehicle costs
the average passenger 0.67 years. It appears that 0.6 hours
is an extremely modest risk.
In examining the risks of a venture, it is only fair
to consider and perhaps even equate the benefits. In the case
of the San Gabriel study, the benefits are difficult to quanti-
tate since the primary objective was improved water management.
However, since the value of water introduced into the earth by
the various recharge operations is expected to reach three
million dollars per year, the knowledge gained from the tracer
study could conceivably benefit the public to the extent of
several million dollars over a 20-year period.
Although the above computations are technically sound,
their acceptance by the man on the street and his political
representative will require a far more emotion-free under-
standing of radiation than now exists. In spite of the
"unpopularity" of the benefit-risk approach to appraising
biological damage from low-level radiation exposure, it is
considered to be the only adequate philosophy enabling us to
live with radiation and make it pay.
A Tracer Application in Waste Disposal Operations
A study has been underway at the Sanitary Engineering
Research Laboratory of the University of California with the
objective of developing design criteria for injection disposal
systems for low and intermediate level radioactive wastes.
The ultimate purpose of this investigation is to make possible
the permanent storage of such wastes in connate water bearing
formations, perhaps at depths of 6,000 to 10,000 feet. Pilot
scale studies have been completed on a shallow confined aquifer
and a simple two-well system, one well serving as the injection
well and the second as a relief well. A layout of the well
field system is shown in Figure 1.

The immediate concern of the study has been to estimate
the time of travel of the radiocontaminant strontium-90 from
the injection to the relief well and to compute the useful waste
storage capacity of the formation. The general approach has
been to employ tritium to trace the movement of water between
wells, and to ascertain the distribution of velocities of flow.
Core samples from the receiving formation have been studied in
the laboratory to determine the ion exchange properties and to
permit the computation of the relative velocities of water and
strontium-90. On the basis of the measured water velocity distri-
bution in the" formation and the relative velocity of tritium to
strontium, it becomes possible to predict, within acceptable
limits of error, the time of arrival of strontium-90 at the
relief well.
The partial results of one field investigation of the
two-well injection system are shown in Figure 2. Although it
appears that some small amounts of strontium-90 arrived at the
relief well (100S) in about 80 days, this is probably due only
to statistical variation in measurement. One hundred and
fifty days of operation were required for the first trace of
strontium to appear at the 100S well.
The use of water tracers appears to be the only satis-
factory means of ascertaining the flow and dispersion charac-
teristics of underground formations and such methods are finding
wide application in the petroleum production industry. Of the
isotopes listed in Table 2, only tritium is satisfactory for
such purposes.
Figures 1 and 2 appear on next page.

12 dto
injection well
188 S
6 dio
relief well
 63N53* W
 45N33 7W
I3S\. ON 2BNT 48N 63N 8BN
--O-*I- -	- -
08 N
63N 53E
 6" dio observation wells
wells designated by distance
and bearing from injection well
M06N69 5E
Flow rate - 17 gal per min
Tritium added - 1st lOdays
Sr^added -1st 24 days
0 7
Tritium Breakthrough C =16*10 >jc/ml
O 04
Sr Breakthrough C = 3 5 * 10 jic/ml

40	50

1.	Pearson, E. A., Tracer Methodology and Pollutional Analyses
of Estuaries. Paper presented at First International
Conference, Waste Disposal in the Marine Environment,
July 22-25, 1959, Univ. of Calif., Berkeley.
2.	Krone, R. B., Annual Report on Silt Transport Studies
Utilizing Radioisotopes, Sanitary Engineering Research
Laboratory, University of California, Berkeley, December
3.	Ellis, W. R., Australian Atomic Energy Commission, Personal
4.	Hull, D. E. and Macomber, M., Flow Measurement by the Total
Count Method. Second International Conference on Peace-
ful Uses of Atomic Energy, Geneva, September 4, 1958.
5.	Kaufman, W. J., Nir, A., Parks, G., and Hours, R. M. Studies
of Low-Level Liquid Scintillation Counting of Tritium.
Proceedings of Conference on Organic Scintillation
Detectors, Univ. of New Mexico, August 1960.
6.	Ljunggren, K., et al. Tracing of Water Flow by Means of
Radioactive Isotopes and Scintillation Counters. Inter.
Jour, of App. Rad. and Isotopes 5, pp 204-212, 1959.
7.	Radioisotopes in Science and Industry. A special report of
the United States Atomic Energy Commission. January, 1960.
8.	Kaufman, W. J., Tritium as a Ground Water Tracer, Paper pre-
sented at 8th annual meeting of California Association
of Sanitarians, Santa Monica, Calif., April 7, 1959.
9.	Jones, H. B., Estimation of Effect of Radiation Upon Human
Health and Life Span. Proceedings of the Health Physics
Society, pp. 114-126 (June 1956).

B. A. Fries*
This symposium up to the end has regarded radioactivity
as a pollutant, now Professor Kaufman and I are here to suggest
its deliberate addition to water streams for useful purposes.
Professor Kaufman has ably defended the thesis that the radio-
logical hazard is a slight one. Our own experience on the dis-
persion of large amounts of tracers, added to measure river
flow, completely supports this view.
Radiotracers are now widely used for water problems;
not only to measure flow rates, but to study flow character-
istics - flow patterns, dispersion, and retention times -
in large bodies of water, and to measure siltation by radio-
traced particles.
In the field of flow measurements, a radioactive method,
the total-count method, has been applied successfully to measure
flows in pipes and in open conduits, such as ditches and rivers.
The procedure and its application to river flows will be dis-
cussed here.
Approximate flow methods have been developed for open
conduits, but these require either obstructions to the flow,
as by weirs or flumes, or extensive velocity traverses of the
channel with a current meter. The dilution method, a well-known
alternate procedure using tracers, does not have the above limitations.
A solution of a chemical or radioactive tracer is added to the
stream at the constant rate, q and concentration, C^. By measuring
the concentration downstream Cq, the total flow Q can be computed.
Q ="C^~ * q, where q < < Q.
*Dr. B. A. Fries, California Research Corporation, Richmond,

This procedures has its own limitations, besides the
obvious mechanical ones. Thus, the samples must be taken,
usually for later laboratory analysis, often enough and long
enough to insure that the final steady state concentration has
been reached.
Total-Count Method
A new radioactive procedure, the total-count method,
transcends most of the difficulties of the older methods. It
shares with the dilution method the following features:
1.	It works in any size or shape of conduit.
2.	There is no pressure drop, loss of hydraulic
head, or obstruction of flow.
It differs in the following ways:
1.	The tracer is added all at once or irregularly,
if necessary, rather than uniformly over a long
period of time.
2.	Measurements are made in the stream as the
transient tracer wave goes by.
The principle is the following: A known quantity of
tracer A is added to the stream. A detector, for example, a
Geiger counter, is placed in the stream at some downstream
point. While the tracer passes, pulses from the counter are
accumulated on the counting scaler. After all the tracer has
passed, the total number of counts, N, corrected for background
is recorded.
The value of N is inversely proportional to the flow
rate since a slow-moving stream allows more time for counts
to accumulate. N is directly proportional to A; the more
tracer, the more counts. Therefore,
N = AQ/F or Q = AF/N.
The proportionality constant F is characteristic of the
isotope and of the counter and its geometrical relationship to
the stream. The dimensions of F are related to those of A and
Q. Thus,
Q gal/min = A microcuries (/y c) x F counts x gal
N counts	c	mn

The value of F can be determined in the laboratory
by a static measurement. A counter is exposed to a tracer
solution in the same geometrical fashion as in the field, and
the counting rate from a known concentration of tracer is
measured. Thus, by rearrangement,
p = counts / ^ c - counts ^ gal
min / gal I	c	min
The divided-stream principle makes the method applicable
to mreasurement of open streams. Supose the tracered stream is
split into two branches, say of equal size, but unequal flow.
The counter is placed downstream below the wye. Now, the
fraction of the flow measured is xQ; but because the tracer
was uniformly mixed above the wye, the fraction of the tracer
passing the counter is xA. Then the number of counts is
N = xA . p _ AF
xQ	Q
Hence, the same number of counts is obtained as on the
whole stream; and it is not necessary to know the value of x.
This makes it possible to gage a large stream by
measuring only a small part of it and, in particular, to measure
open streams. Consider the stream divided by imaginary par-
titions into a number of channels, the size of each channel
corresponding to the effective gamma-ray range of the tracer.
Tracer flowing in more distant channels does not affect the
counter because the exponential absorption of gamma rays in
water limits their penetration to a few feet, and the inverse
square law rapidly diminishes the effective geometry of the
The channel selected for counting may carry a current
faster or slower than the average of the stream, but the same
total count is obtained in this channel as in any other. In
fact, if the whole stream could be forced into this one channel,
the same N would be obtained.
The total-count method has been applied to the measure-
ment of open streams of waste water in petroleum refineries and

to the flow of several modest-size rivers, principally the
American River above Folsom Dam, California.
The counter consists of a bundle of four 1 x 12-inch
Geiger tubes in a waterproof container connected to a portable
battery-operated scaler. The tracers used have been 2.3-year
cesium-134 and 2.7-day gold-198. For flows as large as 1000 ft^/s
up to 1 curie of tracer is required; but this costs only $60 in
the case of gold-198.
The tracer supply is transported in a shielded contained
up the nearest point of approach to the river, then sampled
and measured at this point. It is then transported, unshielded,
on the end of a long carrying pole until it is dumped into the
The results of many tests showed excellent agreement
with a we 11-calibrated current meter. The convenience of the
measurement can be measured by the time required to complete a
test. The accuracy depends critically upon thorough mixing
of the tracer in the stream and upon its persistence in the
stream. Some results illustrating these criteria are given below.
Test Duration
In Table I the time required for the first appearance
of the tracer after its addition and the time required for the
tracer wave to pass are 9hown.
Table I
Time of Passage, Minutes
South Fork, American River, Flow 1000 ft^/sec
Gold-198 Tracer
Test No.	Distance,Ft. First Appearance Tracer Wave


In addition to these times, some time is also required
for a preliminary background count to complete a test. Actually,
the total time of passage does not vary much with the size of the
stream. A test on a natural stream 100 times smaller than the
above took about as long.
The extent of mixing was determined by comparing the total
count measured on opposite sides of the stream. The results of
several tests are shown in Table II.
Table II
Extent of Mixing
American River, Flow 1000 ft^/sec
Gold-198 Tracer
Test No.
Mixing ,7o
4 turns
Lower North
2 turns
Sou th
Theresults show that it is not difficult to attain complete
mixing in turbulent streams within relatively short distances.
Mixing was complete in 1/4 - 1/2 mile, depending upon the config-
uration of the river.
The loss of tracer through precipitation or adsorption
on the soil or on algae in the stream bed was measured by compar-
ing the total count recorded on several counters distributed
along the river. In 1958, Test 1 and 2 (Table I), 3 counters at
distances of 1/2, 1, and 2 miles showed the same total count
within "t 2%. The dropout was thus less than 37 in 2 miles. In

Test 3, the dropout was 8% at 4 miles, based on an upstream
reading. Part of this was caused by incremental flows from
tributary streams. Hence, a reasonable upper limit of the loss
is 2% per mile.
The range of distances over which satisfactory measurements
can be made are determined as follows:
1.	The lower limit is set by the requirement of
complete mixing.
2.	The upper limit is set by the loss of tracer.
3.	A practical upper limit, in the absence of any loss
of tracer, is set when the dispersion of tracer
along the stream becomes so great that the net count-
ing rate is small compared to background or when
too much time is required to observe the passage of
the tracer wave.
In tests described here, the practical upper limit was about
2 miles.
Radiological Safety
The rapid longitudinal dispersion in the stream quickly
reduces a concentrated solution of tracer to tolerance levels
for drinking water. From the practical view, there is a use-
ful upper limit to the tracer concentration set by counting
conditions. Geiger counters become inaccurate at rates above
100 counts/sec. With the bundle of 4 tubes we use, this rate
is attained at a concentration of 2 x 10"^ c/cc for gold-198;
the tolerance level for continuous use in drinking water is
currently 3 x 10"^ >cc/cc.* In the tests described, the peak
count rate was much less than 100 counts/sec. Dilution to
tolerance levels was achieved within several minutes after the
addition of tracer.
External gamma-ray exposure to a swimmer in the water
was negligibly low, about 0.0025 mr per test. The only pre-
caution taken was to exclude swimmers between the tracering
point and the counting station during the tests.

* Effective January 1, 1961, this concentration will be reduced
to 5 x 10-^ /C< c/cc (Title 10, Atomic Energy; Part 20, Standards
for Protection Against Radiation, Paragraph 20.106). However,
for the purposes of this regulation, concentrations may be
averaged over a period of one year. Hence, this change in no
way restricts the tracer application.
1.	D. E. Hull, J. Appl. Rad and Isotopes 4, 1 (1958).
2.	D. E. Hull and M. Macomber, 2nd International Conference,
United Nations, Geneva J^), 324 (1958).
3.	D. E. Hull, 3rd Industrial Nuclear Technology Conference,
September 22-24, 1959, Chicago.
4.	U. S. Patents, 2,826,699 and 2,826,700, D. E. Hull, assigned
to California Research Corporation.

Q: What is the method for computing the flow?
A: We are using the formula Q = ~jjf  A is the millicuries
added. N is the total number of counts. For instance, in
the American River we added 1,000 millicuries and had a count
of 10,000 (actually, the count may have been 11,000, but it
was necessary to subtract the background of 1,000). F is the
count of millicuries per gallon per minute. All you do is add
the isotopes and count the number of radiations. F is determined
in the laboratory.
Q: What brand of tube is used?
A: It doesn't make any difference.
Q: How about aging7
A: We have used our tubes a long time and they have presented
no problem. They cost about $15.00.
Q: Couldn't this be done by collecting samples from the stream,
compositing them and then running the analysis for radio-
activity in the laboratory?
A: Yes, but you wouldn't know when to start and when to stop
taking samples. This might entail the collection of a larger
number of samples than are necessary. By running the analysis
in the field, we know exactly when to start and when to stop
by the counts obtained.
Q: In certain situations where it would be undesirable to use
radioactive tracers, could you use nonradioactive tracers?
A: Yes, you could use some colored dyes for instance, and compare
the density of color. While this is possible and may avoid the
need for obtaining approval for their use, it isn't as convenient
as the isotope method. Actually, the scaler used with the isotope

Is a totalizer. It adds up and totalizes the flow. This
method was used very successfully in Seattle a few years ago
as a means of measuring flows in sewers. They set up depth-
recording instruments in a number of major trunk sewers, and
used this method for determining the rate of flow under various
depths of sewage in the trunks.
Wiers and such other types of measuring devices become
clogged and require constant cleaning. This is not a problem
with the Isotope method.
Q: How would you get the value of F for a 36" sewer flowing
partly full?
A: This cannot be done directly in the sewer. The sewage is
pumped into a standard counting bucket. This is our divided-
stream principal. F varies with the Geiger counter you use.
This is the principal that they used in Seattle.
Q: Can this same method be used with a large stream?
A: It could. We found it easier to put the tubes in the water.
Q: Isn't the value of F somewhat related to the size of the
A: No. Only to the counter and the tracer. It is important
to place the tubes in a position some distance from the shore
and submerged about a foot under the surface.

November 15, 1960
James L. Agee
E. Jerry Allen
H. R. Amberg
Joseph T. Barnaby
George D. Barr
A.	F. Bartsch
Fred J. Burgess
John V. Byrne
Richard J, Callaway
Glen D. Carter
George D. Chadwlck
D. Chakravarti
David B. Charlton
J. F. Cormack
John Courchene
Gilbert H. Dunstan
Leonard B. Dworsky
Edward F. Eldridge
Ken Englund
Richard F. Foster
B.	A. Fries
John Girard
Pete Hildebrandt
Allan Hirsch
G. LaMar Hubbs
Roger James
Clyde R. Johnson
R. L. Junkins
Earl N. Kari
Warren J. Kaufman
Arthur R. Keene
J. G. Knudsen
L. B. Laird
Milton W. Lammering
Robert E. Leaver
Byron E. Lippert
Alfred Livingston
Robert J. Madison
Bruce McAlister
Alfred T. Neale
R. H. Nussbaum
Charles Osterberg
U. S. Public Health Service	Portland
Seattle Water Department	Seattle
Crown Zellerbach Corp.	Camas
U. S. Fish & Wildlife	Portland
Oregon State Board of Health	Portland
U. S. Public Health Service	Cincinnati
Oregon State College	Corvallis
Oregon State College	Corvallis
U. S. Public Health Service	Portland
Oregon State Sanitary Authority	Portland
U. S. Public Health Service	Corvallis
University of Washington	Seattle
Charlton Laboratories	Portland
Crown Zellerbach Corp.	Camas
Seattle Water Department	Seattle
Washington State University	Pullman
U. S. Public Health Service	Portland
U. S. Public Health Service	Portland
Atomic Energy Commission	Richland
General Electric Co.	Richland
California Research Corp.	Richmond
Washington State Dept. of Health	Seattle
Washington State Dept. of Health	Seattle
U. S. Public Health Service	Portland
U. S. Public Health Service	Anchorage
Washington State Dept. of Health	Spokane
Portland State College	Portland
General Electric Co.	Richland
U. S. Public Health Service	Portland
University of California	Berkeley
General Electric Company	Richland
Oregon State College	Corvallis
U. S. Geological Survey	Portland
U. S. Public Health Service	Cincinnati
Washington State Dept. of Health	Seattle
Portland State College	Portland
Washington Pollution Control Comm. Olympia
U. S. Geological Survey	Portland
Oregon State College	Corvallis
Washington Pollution Control Comm. Olympia
Portland State College	Portland
Oregon State College	Corvallis

Ralph F. Palumbo
University of Washington
Wta. G. Pearcy
Oregon State College
John R. Prince
Oregon State College
Robert L. Rulifson
Oregon Fish Commission
V. F. Santos
U. S. Geological Survey
Clyde S. Sayce
Washington Dept. of Fisheries
Arthur F. Scott
Reed College
Allyn Seymour
University of Washington
Robert L. Stockman
Washington State Dept. of Health
J. D. Stoner
U. S. Geological Survey
Robert N. Thompson
Oregon Fish Commission
John D. Thorpe
Good Samaritan Hospital
Ernest C. Tsivoglou
U. S. Public Health Service
R. A. Wagner
Washington Pollution Control Comm.
Michael Waldichuk
Fisheries Research Board of Canada
Nanaimo, B.C.
R. B. Walton
Portland State College
Jack Weathersbee
Oregon State Board of Health
R. E. Westley
Washington Dept. of Fisheries
C. F. Whetsler
City Water Department
Pasco, Wn.
John N. Wilson
U. S. Public Health Service
Paul Zimmer
Bureau of Commercial Fisheries