-------
     b.    Pollutant concentration can be increased by highly
          contaminated runoff.

     For the long-duration pollutants shown in Figure A-7
     (heavy metals, nutrients, etc.) either condition may
     produce problems.  The concern should not be so much
     with the peak loadings which occur with heavy runoff,
     but rather with the long-term, average loads.  For
     these types of pollutants, steady-state water quality
     criteria may be appropriate (when applied to average
     conditions rather than peak storm conditions).

     If the first condition is applied to the short-term
     pollutants listed in Figure A-7 (BOD and bacteria) then
     runoff is unlikely to cause a problem because these
     pollutants will decay and be assimilated in the stream.
     If the short-term pollutant concentration increases
     (Condition 2) a transient problem may occur.*

     If, for example, a dissolved oxygen sag occurs due to
     BOD decomposition, a decision must be made on whether
     this sag is harmful and nonpoint controls are neces-
     sary.  Comparison of the low DO with steady-state DO
     criteria is not appropriate because the criteria  (say
     4.0 mg/1)  is generally based upon aquatic life reaction
     to several consecutive days of low DO levels.  Post-
     storm DO levels may drop below 4.0 mg/1 for several
     hours and then recover to 5-6 mg/1.  The decision on
     whether a problem exists should be based on the impact
     of the short-term sag on aquatic life.  Biological
     assessment can aid in this determination.  Also, re-
     search, as depicted in Figure A-9, may lend itself to
     assisting in establishing water quality criteria appli-
     cable to short-term storms.  The figure shows the mor-
     tality of trout as a function of short-duration DO
     levels.  The figure is an example of how bioassay data
     based on laboratory tests may be presented; it does not
* See following section for detailed discussion of BOD/DO
  relationship.
                         A-45

-------
  show antagonistic effects of other pollutants.  Never-
  theless,  information similar to that  shown in the figure
  could be  applied to establish short-term DO conditions as
  follows:*
  a.
Establish percent mortality acceptable;  this would
have to be  linked to storm frequencies.

Determine DO/time relationship of worst  storm
(i.e., runoff)  condition occurring once  a year.
This can be  approximated by examining  existing data
or receiving water modeling.  For example,  assume
that this worst case condition results in a minimum
DO of 1.0 mg/1  for 50 minutes.

Referral to  Figure A-9 indicates that  a  value of
1.0 mg/1 for only 30 minutes causes  80%  mortality.
         <
         H
         
-------
     Decomposition and Reaeration at High Flow:  Depending
on the physical characteristics of the receiving stream,
climatic conditions, and the storm-related BOD load, the
stream's dissolved oxygen levels may increase or decrease.
The following paragraphs indicate that in relatively small,
fast moving streams, BOD from storm runoff probably is not a
problem.  If the BOD is not decomposed by the time it
reaches slower moving downstream water bodies  (e.g., estu-
aries, impoundments), DO depletion problems may occur, de-
pending on the assimilative capacity of the downstream body.

Both decomposition and reaeration rates are affected by a
number of variables.  The following paragraphs list a number
of these factors and briefly describe the general impact of
each factor on decomposition and reaeration rates.  Special
emphasis will be placed on those factors directly related to
storm events.

The biological decomposition of organic matter is commonly
conceptualized by the following equation:
where:
     Lt = BOD at time t

     L0 = initial (ultimate) BOD

     Ki = overall deoxygenation rate (day  )

     t  = time since discharge (days)
The amount of decomposable matter in the stream is usually
measured in terms of biochemical oxygen demand (BOD)  which
is defined as the amount of dissolved oxygen consumed in the
bacterial oxidation of decomposable matter.

Reaeration can be defined as the replenishment of dissolved
oxygen.  This is basically a chemical and physical process,
although some biological processes may come into play.  Re-
aeration can be considered as a function of molecular diffu-
sion and the following stream characteristics:  depth, velo-
city, slope and channel irregularity.  The reaeration rate
is used to calculate the stream DO deficit which is commonly
conceptualized by the following equation:
                         A-47
-------
            -K2t
     D  = D e
      t    o
where:

     Dt = DO deficit at time t

     D0 = initial DO deficit

     K2 = reaeration rate  (day"1)

     t  = time  (days)
The reaeration rate  (K2) is considered a function of stream
geometry.


          (C,) (u) 2
      2    (H)C3


where:

     K«       = reaeration rate

     u        = stream velocity

     H        = stream depth  (ft)

     C-i,Co/Co = empirical constraints
While the decomposition is basically the biological process,
reaeration can be termed a physical and chemical process.

Table A-11 lists general factors which affect the decomposi-
tion (K^) and reaeration (K2) rates and indicates the gen-
eral impact of each parameter on these rates.  Both temper-
ature and turbulence effect decomposition and reaeration.
Flow has a negative impact on reaeration and can increase or
decrease the decomposition rate depending on whether the
runoff concentration is higher or lower than the in-stream
concentration.  The table also indicates that the in-stream
BOD concentration directly affects the decomposition rate.
                            A-48
-------
The ultimate allowable BOD loading generally increases as
flow increases or as temperature decreases.  This is under-
standable since an increase in flow will generally improve a
stream's assimilative capacity due to increased dilution
while a decrease in temperature will lower the decomposition
rate, and therefore, allow larger BOD loads without deplet-
ing additional DO.  Figure A-10 graphically presents the
relationship between the reaeration rate (1^) and flow.  A
number of researchers have developed specific reaeration
equations based on observations in various types of streams.
These various equations have been plotted against flow to
reflect the wide range of reaeration rates that have been
observed in different types of streams for different flow
periods.  It should be noted that most of the reaeration
rates are observed to decrease as flow increases.
                         TABLE A-11

             EFFECT ON STREAM DECOMPOSITION AND
       REAERATION RATES OF INCREASING VARIOUS FACTORS
                          Effect on           Effect on
                        Decomposition        Reaeration
Factor Increased            Rate	           Rate

Temperature              Increase            Decrease

Turbulence               Increase            Increase

Flow                     Decrease*           Decrease

BOD Concentration        Increase            No direct effect

Dissolved Oxygen         Increase            Decrease
Concentration


* Assuming dilution of in-stream BOD concentration

Source:  Betz Environmental Engineers,  Inc.
                            A-49
-------
    1.00

   0.90

   0.80

   0.70

_  0.60
'>»
2  0.50
 o
it:
   0.40

   0.30

   0.20

   0.10
T      I      I      I      I      I      I      I
                  -6AMESON
                       ''CONNOR 8 DOBBINS
                        OWENS, EDWARDS  a GIBBS
                     -LANGBEIN &  DURHAM
  -CHURCHILL, ELMORE a  BUCKINGHAM
              I
       I
I
I
I
I
I
      0      100   200   300   400   500   600   700   800   900  1000

                                  FLOW (cfs)


     Figure A-10 KA vs. FLOW AS CALCULATED BY  VARIOUS PREDICTION EQUATIONS
      Source:   Whipple,  et al,  1974
                              A-50
-------
Table A-12 presents various factors directly attributable to
storms and their impact on decomposition rate, reaeration
rate, and the likely overall impact on the DO concentration
in slow and fast moving streams.  The overall impact of a
storm on the dissolved oxygen concentration will vary de-
pending on the physical characteristics of the stream.

For streams exhibiting moderate to fast velocities, the DO
profile during a storm would reflect an initial upward surge
in the dissolved oxygen profile due to the highly oxygenated
runoff entering the system.  This initial pulse is generally
followed by a gradual return to the pre-storm DO level.  In
moderate to fast moving streams, most of the additional BOD
entering the stream is flushed from the system before it has
a chance to exert an oxygen demand on the stream.  In slower
moving streams, the DO profile would be similar, except that
the return-to-normal stage would also include a possible
dissolved oxygen sag below the pre-storm level due to the
exertion of material that had not been flushed from the
system.

An illustration of this dissolved oxygen sag is provided in
Figure A-ll which plots the dissolved oxygen concentration
and the corresponding stream flow observed during three
typical storms on the Passaic River at Little Falls, New
Jersey.  All three storms indicate an initial surge of dis-
solved oxygen followed by a gradual sag.  The dissolved
oxygen usually continues to decline below the level which
prevailed at the beginning of the storm, reaching a minimum
value 4-9 days after the hydrograph peak.  The DO concentra-
tion then recovers while the hydrograph is still falling.
This general path was observed for 80% of the recorded
storms at Little Falls occurring between May and October
1971 to 1973.  The Passaic River is a lethargic stream
containing numerous benthic deposits.  One explanation of
the dissolved oxygen sag is that oxygen demanding material
is scoured from these benthic deposits and resuspended
during the course of the storm, and exerts a DO demand
during the post-storm period as stream velocities return to
normal.

     Influence of Benthic Deposits on Water Quality;  The
above example indicates that benthic deposits can have sig-
nificant impacts on a stream's dissolved oxygen levels.
Benthic deposits can also be sources of nutrients, heavy
metals and other deleterious parameters.  In the above case,
it was indicated that the DO depletion was from the resus-
pension of deposits by high flows following a storm.  Ben-
thic deposits may also cause oxygen depletion during low
                           A-51
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                                            A-52
-------
     6O-
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 woo-

                               PASSAIC RIVER AT  LITTLE FALLS
                               STORM OF:  8/1/73  -f 8/14/73
     ,  OItJ45S7«»«flWT»14
                                PASSAIC  RIVER AT LITTLE  FALLS
                                STORM OF:   7/29/71 - 8/12/71
                               "V
      *
-------
flow, steady-state conditions by releasing organic nitrogen
and ammonia from the benthic layer, which then undergoes
decomposition in the stream.  Table A-13 presents typical
oxygen uptake rates of sediment deposits.

Ogumrombi and Dobbins  (1970), showed that two major proces-
ses exert oxygen demand on the water:

     1.   Addition of BOD from benthic deposits.  The rate
          of this addition is designated as La  (mg/l/day).

     2.   The removal of DO to satisfy the BOD of organic
          material within the top aerobic layer.  The net
          rate of removal is designated as DJ-,  (mg/l/day) .

The authors presented data which indicated that both La and
DJ.J decrease with time.  This is depicted in Figure A-12,
which shows BOD and the oxygenation rate of the supernatent
effluent stream.
                         TABLE A-13

      AVERAGE VALUES OF OXYGEN UPTAKE OF RIVER BOTTOMS
Bottom Type and Location

Sphaerotilus -  (10 gm dry wt/m^)
Municipal sewage sludge-outfall
  vicinity
Municipal sewage sludge - "Aged"
  downstream of outfall
Cellulosic fiber sludge*
Estuarine mud
Sandy bottom
Mineral soils
Uptake (gms 02/m  - day)
	@ 20°C	
                 Approx.
  Range          Average
   2-10.0

   1-2
   4-10
   1-2
 0.2-1.0
0.05-0.1
1.5
7
1.5
0.5
0.7
* Calculated from reported uptake values of 2-5 and 3.5
  gms/m2/day at
Source:  Thomann, R. J., "Systems Analysis and Water Quality
         Management," McGraw-Hill, 1972.
                         A-54
-------
Review of Ogumrombi and Dobbins data demonstrates that
sludge depth has a significant impact on both parameters,
whereas retention time does not.  The effect of depth can be
seen from Figure A-13, which shows a mass curve of total
oxygen consumed.  The total oxygen is the sum of the oxygen
demand by the benthic deposits plus the oxygen consumed
through decomposition of the BOD added to the supernatent
water.

Let us use Figure A-13 in a hypothetical example to demon-
strate the significant impacts of controlling the oxygen
demand of benthic sources.  Suppose that we have a stream in
which benthic demand is a significant component of the total
oxygen demand and control of benthic sources is being in-
vestigated.  Let us further assume that the benthic problem
is a long-term one and that the 36-day values presented in
the figure are the parameters of interest.  Our existing
sludge depth is 7.62 centimeters and exerts the total oxygen
demand of 27 milligrams per square centimeter.  Computations
indicate that we must reduce the oxygen demand of the ben-
thic layer to 16 milligrams per square centimeter.  The
figure shows that in order to cut the oxygen demand by a
factor of less than half, the sludge depth must be cut by a
factor of 3 (down to 2.54 centimeters).

Other conclusions pertinent to the study of benthic demands
are:

     1.   On the average, La appears to be about 28% of D^
          in terms of mg/l/day.

     2.   The value of La and DJ-J for a fresh sludge deposit
          which is not continuously being replenished are
          gradually reduced with time.

     3.   Both La and DJ-, increase with increase in depth of
          sludge deposits; however, they do not vary in
          direct proportion to the depth of the deposit.
          The values of these parameters per unit depth de-
          crease as the depth of the deposit increases.

     4.   When the environment in the supernatent water is
          aerobic, La and D]-> are independent of the concen-
          tration of DO in the supernatent water;  however,
          in an anaerobic environment, the value of DJ-, is
                          A-55
-------
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        I   I   I   I   I   I   I   1   1    I   I   I
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                   b CAICUIATCD  FROM SMOOTH CUFVf OF f-DAV BOO
                   O MtAWIICD J-DAY BOO
                                   10  II  12  13  U
                         DAYS
 Figure A-12    BOD AND DEOXYGENATIONJATE CONSTAJH
            OF EFFLUENT STREAM FLOWING OVER  SLUDGE
            AND  BED (7.62  CM SLUDGE DEPTH )
Source:   Ogurombi and Dobbins, 1970
   31.0
   36.0
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               *  10  I?  I* 16  It  20  22  24 26  2t  30  32  M 3ft
 Figure A- 13  MASS CURVES OF TOTAL OXYGEN CONSUMED,
            Oc,  BY BFN1HAL DEPOSITS
   o REACTOR J    A REACTOR II SLUDGE DEPTH  7.62  CM
   •REACTOR III  v REACTOR IV, SLUDGE DEPTH 2.54 CM
Source:   Ogurombi and Dobbins, 1970
                       A-56
-------
          limited by the rate at which the DO is applied to
          the supernatent water, while the values of La are
          relatively unaffected.

A later article  (Fillos and Molof, 1972) supported most of
the findings of Ogumrombi and Dobbins.  Some of their con-
clusions were:

     1.   A critical sludge depth of 3-4 inches exists; at
          depths greater than this, oxygen uptake rate is
          independent of depth.

     2.   BOD, PO^ and NH3 are released more rapidly as
          supernatent DO drops below 2-1.5 mg/1.*

     3.   The conclusion on BOD differs from the earlier
          study.  The more recent study concluded that al-
          though D]-, was generally dominant, La became a
          major factor affecting the oxygen economy of the
          stream when DO was greater than 1.5 mg/1.

Fillos and Swanson (1975) studied the release rate of nu-
trients from river and lake sediments.  The authors indicate
that release of nutrients, such as ammonia and phosphorus,
may be sufficient to maintain the eutrophic state of waters
long after external sources have been eliminated.

Benthal deposits were collected and analyzed from Muddy
River and Lake Warner, both in Massachussetts.  Phosphate
and iron releases were found to be heavily dependent on the
presence of a thin aerobic layer on the benthic blanket.
Anaerobic conditions resulted in a sudden increase in phos-
phorus and iron releases.  The orthophosphate release rate
from Muddy River sediments averaged 9.6 mg/day/sq meter (_as
P)  under aerobic conditions.  Lake Warner demonstrated the
following orthophosphate release rates:

     Aerobic (avg) 1/2 mg/day/sq meter

     Anaerobic (max)  26 mg/day/sq meter
* This may be very important in nutrient analysis of im-
  poundments where DO at bottom may be close to zero.
  Another ramification is that lower DO (below 2 mg/1)
  results in more release of BOD and NH^,  which further
  exacerbates the DO situation.


                            A-57
-------
Ammonia levels were not found to vary with aerobic/anaerobic
conditions.

The following release rates were reported for ammonia nitro-
gen (as N):

     Muddy River    15 mg/hr/sq meter

     Lake Warner     5 mg/hr/sq meter

It is clear from this study that short-duration intermittent
anaerobic conditions in the immediate overlying water are
capable of causing dramatic increases in the release rates
of nutrients from sediments.  Such anaerobic conditions may
be localized and may result from the oxygen demand of the
sediments themselves.  Therefore, in any lake management
procedure, the sediments must be treated as intermittent
sources of nutrients and as a continuous sink for oxygen.

     Types of Water Bodies and their Significance;  Pollu-
tant effects on water chemistry and aquatic ecology will
vary significantly, depending on the type of water body the
pollutant is discharged into.  The three water bodies dis-
cussed below--streams, lakes, impoundments--each have hy-
draulic, ecological and physical differences which affect
the fate of pollutants.  The stream discussion which follows
focuses on free-flowing streams rather than estuaries.
Estuaries, being influenced by tidal action, may have pol-
lutant transformation taking place which have characteris-
tics similar to streams and impoundments and unique to estu-
aries.

This discussion will deal primarily with the mechanisms of
pollutant transport and transformation of sediment and
nutrients.  Discussion of these pollutants will indicate the
kinds of phenomena that occur when other types of pollutants
are discharged to these waters.

1.   Streams

     The fate of the sediments entering cannot be determined
     a priori without knowing the characteristics of the
     basin.  Slope, water velocity, particle type and size
     all play an important role in sediment transport.  At
     best, a few generalities can be made.
                          A-58
-------
     a.    As velocity increases,  the distance of transport
          increases

     b.    Larger and more dense particles settle out fdrst

     c.    Sedimentation occurs in pool areas

     d.    Turbulence will act to  maintain particles in sus-
          pension*

     The interaction between water velocity and sediment
     transport is a complex relationship.  In general, as
     the velocity increases the rate of settling decreases;
     simultaneously, bank scour may also increase,  causing
     an increase in the total solids being transported in
     the stream.  According to Leopold (1968) a stream 2 ft.
     deep and 11 ft. wide carrying 55 cfs at bankfull stage
     would have to increase to 3  ft. by 20 ft. to accommo-
     date a 2.7 times increase in maximum flow.  An increase
     of this magnitude could occur as a result of develop-
     ment.  These figures indicate that even if erosion were
     controlled during development, impervious surfaces
     could cause increases in flow that would result in
     higher sediment loadings, at least temporarily.
     Sedimentation problems could also occur as a result of
     shifting substrates and thereby cause a loss of certain
     aquatic species.

     An example of the difficulty of relating suspended
     solids data to sedimentation is provided by Hoak
     (1959).   At Braddock, PA. the mean suspended solids
     load in the Monongahela River is 1,924 tons/day; the
     volume about 345 acre-ft/mile.  If the sediment load
     settled and stayed at this point the channel would be
     filled in in a little less than one year (Hoak, 1959).
     This example indicates that  sedimentation occurs, but
     constant shifting of this material also occurs.
* There is some evidence to suggest turbulence may in some
  cases increase agglutination of particules,  increasing
  settling capacity.   Turbulence can also result in sus-
  pended matter becoming dissolved.  See Hoak, 1959.
                          A-59
-------
     A more general idea of where sedimentation problems
     will occur in a stream can probably be determined from
     information on soil types and by locating pool areas
     where water velocities decrease (the latter from on-
     site observation and topography maps).

     Much of the transport of nutrients in streams is close-
     ly associated sediment transport.   Phosphorus in par-
     ticular is readily adsorbed onto soil particles.
     Nitrogen is also transported on soil particles but
     tends to be more soluble.  The fate of these nutrients
     in the stream beds is dependent on several factors.
     Phosphorus and nitrogen in forms associated with par-
     ticulate matter will disperse according to the mechan-
     isms of particle dispersion.  The dissolved fractions
     will either be immediately absorbed by aquatic vegeta-
     tion or carried downstream.  Factors affecting this
     process are:

          water velocity and turbulence
          microorganisms and vegetation
          turbidity
          temperature
          particle size and type
          channel characteristics
          temperature

     The dynamics of phosphorus in streams is discussed in
     greater detail by Ryden et al (1972).

     Assuming no additional inputs of nutrients, concentra-
     tions decrease as materials proceed downstream.  This
     is due to uptake by organisms and dilution by the en-
     trance of cleaner water—assuming the other inputs are
     in fact cleaner.

     The extent to which nutrients settling out affect the
     stream depends on the particular situation.  During
     storm conditions with accompanying high flows, sediment
     material often becomes resuspended, which essentially
     acts as a new input into the stream.
2.    Lakes
     Determining the amount of sedimentation occurring in
     lakes is even more difficult than in stream systems.
     Although it may be assumed that lakes act as a settling
     basin for incoming streams, and therefore, essentially
                            A-60
-------
all entering suspended matter eventually settles on the
bottom, this information does not solve the problem.
Nonpoint sources are generally from diffuse sources of
runoff that are difficult to measure.  Even where in-
puts can be measured, current patterns and eddies which
may not be constant make it difficult to determine
where sedimentation will occur.  Lake turnover may
resuspend solids, creating further impacts.  The ini-
tial point of entry is usually a major sedimentation
point due to the abrupt decrease in velocity at this
point.  However, it may not be the only area affected.

The dynamics of nutrients in lakes and reservoirs is
incompletely understood.  In an essentially closed lake
system, the nutrients entering remain in the system;
they are either utilized by the vegetation, settle out,
or remain in solution.  Which path is taken depends on
the water body characteristics and the nutrient form.
Nitrates and phosphates in solution are readily avail-
able for plant growth.  This is also true of ammonia
which can be utilized as a nitrogen source by many
types of aquatic vegetation.  Ammonia may also be
oxidized to nitrate before being incorporated into
plant biomass.

Nutrients associated with particulate matter tend to
settle out and become part of the sediments, but a num-
ber of factors may affect this process.  Turbulence
will tend to keep particles suspended and may also re-
sult in nutrients going into solution.  Current pat-
terns and eddies may cause suspended matter to settle
out far from the point of input, making impacts dif-
ficult to determine.

To what extent nutrients tied up in the sediments are
available to aquatic life is not definitely known.
Phosphates in particular tend to form very stable com-
plexes with elements such as iron and aluminum.  Some
evidence suggests that sediment runoff into reservoirs
and lakes may actually reduce dissolved ortho-phosphate
levels by forming complexes that precipitate due to the
rapid equilibrium between water and sediments  (Heine-
mann, in Ackermann et al, 1973).  However, these sedi-
ments could later supply phosphorus to aquatic organ-
isms when the sediments are stirred up during turnover,
turbulence, or even by bottom feeding fish such as carp
and catfish.
                       A-61
-------
3.   Impoundments

     In impoundments, calculations of sedimentation can be
     as difficult to obtain as sedimentation estimates for
     lakes.  Although the amount of sediment existing through
     the discharge stream may be measurable, problems simi-
     lar to those found in lakes remain.  Assuming that the
     entrance and exit of suspended solids can be determined,
     it is then necessary to consider retention time in the
     impoundment and whether the impoundment stratifies and
     undergoes turn-over, resuspending solids.

     In spite of the complexities involved, a number of
     studies have been done on sedimentation in reservoirs.
     From these studies a few general trends have been ob-
     served:

     a.   There is an inverse relationship between size of
          reservoir and rate of filling in.

     b.   Particules tend to be deposited in a gradation of
          particle sizes along the longitudinal axis of the
          reservoir.  Coarser and heavier particles are
          dropped in the headwater and finer sediments are
          deposited toward the dam.   (Note:  This is af-
          fected by:  water level, temperature and dissolved
          minerals, mineral composition of the sediments,
          especially clay-sized fraction; volume relation-
          ship of reservoir storage capacity and influent
          water; configuration of basin; and amount of
          sediment previously deposited.)

     The factors affecting sedimentation in reservoirs are
     discussed in greater detail by Glymph  (in Ackerman et
     al, 1973).  Data on reservoir sedimentation in the
     United States are provided by Bendy et al (in Ackermann
     et al, 1973).  These data support the generally held
     hypothesis that, as drainage area increases, sediment
     yields decrease.  Therefore, the greatest sedimentation
     problems tend to occur in small upland reservoirs.  A
     summary of sediment accumulation data for the reser-
     voirs surveyed is presented in Table A-14.

     There are some differences in nutrients between natural
     lakes and impoundments, although the basic principles
     apply.  Impoundments are not a closed system and many
     nutrients may be removed due to greater concentrations
     near the bottom.  There may also be a greater input of
                          A-62
-------








































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A-63
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     nutrients into a reservoir system because of the drain-
     age pattern.  Rivers characteristically carry higher
     concentrations of nutrients than lakes.  By damming a
     river, these higher concentrations are retained in the
     system.  The addition of nonpoint sources of nutrients
     to such a system could accentuate the buildup if flows
     are never high enough to flush the system.

     Some Comments on Probable Controls:  A recent paper by
Barker (1974)  offers several ideas on implementation con-
straints of nonpoint controls and how they might affect the
study of nonpoint problems.  They are presented here to give
a perspective; adoption of Barker's convictions may have
significant ramifications on the type of nonpoint analysis
pursued.

Barker turns his focus beyond the investigation of nonpoint
pollution sources to the implementation and enforcement of
justifiable controls.  In doing so, he argues that, because
of implementation constraints, we can usually determine the
control recommendations which will be coming from 208 pro-
grams after all the nonpoint study, assessment and analysis
is completed.   Barker's conclusions are indeed controversial
and, by his own admission, "perhaps in excess."  However,
they are valuable in that they run counter to the conven-
tional wisdom and may force rethinking of some preconceived
notions.

The following points summarize some of Barker's conclusions:

     1.   Nonpoint controls for agriculture will consist of
          the same principles the Soil Conservation Service
          has espoused since the 1930s unless the economic
          structure of farming is drastically redefined.

     2.   The only practical controls for most urban runoff
          problems are related to sediment and erosion.

     3.   Mathematical modeling of nonpoint wastes is a very
          inexact science and may not be a cost-effective
          approach.

     4.   Legal defense of recommended control measures is
          extremely important because it is likely that
          controls will be challenged by an uncooperative
          developer or land owner.  Thus, it is imperative
          that nonpoint recommendations be based upon accur-
          ate supportive data and an acceptable methodology.
                           A-64
-------
Biological Effects of Nonpoint Source Pollutants

A clear understanding of the biological impacts of nonpoint
source pollutants is necessary to adequately assess the
severity of the nonpoint problem.  Determining water quality
criteria applicable to nonpoint phenomena and the nonpoint
pollutant reduction goal also require a thorough knowledge
of pollutant impact on water ecology.

Unfortunately, little information is available on the speci-
fic effects of nonpoint source pollution on the biological
systems of water bodies.  Although there are special circum-
stances associated with nonpoint source pollution, the
source of an adverse input has no effect on the response of
the organisms involved.  Therefore, general responses of
organisms to various pollution substances associated with
nonpoint source will be discussed.  In addition, the special
aspects associated with nonpoint pollution will be con-
sidered in these discussions.

The following discussion will focus on the biological impact
of six conditions/pollutants which are associated with non-
point sources:

     Low Oxygen Conditions

     Flow Effects

     Suspended Solids

     Nutrients

     Toxic Substances

     Road Salts

     Responses to Low Oxygen Conditions:  A decrease in dis-
solved oxygen is one of the problems that frequently accom-
panies nonpoint source pollution.  The effect of this de-
crease on aquatic biota depends on the amount of the de-
crease, the type of organism, the duration of the oxygen
depression, and whether other adverse conditions accompany
the oxygen drop.

The responses of fish to short term low oxygen conditions
are not well defined.  Doudoroff and Warren (1962) sum-
marized previous studies and concluded that little mortality
                          A-65
-------
would be expected at concentrations near and above 3.0 mg/1,
even for prolonged periods, provided other harmful agents
were-not present.  A concentration of 2.0 mg/1 may be cri-
tical for sensitive forms, but at low temperature, concen-
trations as low as 1.0 mg/1 may be tolerated by acclimatized
fish.   The key factors affecting tolerances appear to be
conditioning of the organism, temperature, and the presence
or absence of other adverse factors.  Fish have been found
to grow little, or not at all, in the presence of abundant
food at reduced oxygen concentration even though these
levels could be tolerated for long periods of time (Doudo-
roff and Warren/ 1962).   Specific species were not named in
the above summary.

In another study, carp and buffalo were reported in water
carrying as little as 2.2 mg/1 dissolved oxygen; however, a
variety of fish species were found only where a minimum of
4.0 mg/1 was present.  The greatest variety of fish were
present in waters carrying 9.0 mg/1 dissolved oxygen (Ellis,
1957) .

It is apparent from the available information that many fac-
tors affect the response of fish to a decrease in dissolved
oxygen.  Acclimatization was a factor in Doudoroff's find-
ings (1962).  This means fish gradually exposed to a gradi-
ent of low dissolved oxygen concentration will have a better
chance of surviving than fish in an environment where the
dissolved oxygen undergoes a sudden drop, which is fre-
quently the case in nonpoint source pollution.  Temperature
is also a critical factor, with high temperatures accentu-
ating the effects of oxygen stress.  The presence of other
factors, such as suspended matter and toxic substances, that
frequently accompany low dissolved oxygen conditions, also
reduce tolerances to oxygen stress.

Seasonal factors must also be considered.  High temperature,
low flow periods would be more critical than low tempera-
ture,  high flow periods.  Oxygen-demanding substances would
also be more critical during spawning seasons because of the
greater susceptibility of hatchlings and fry to oxygen
stress.

The response of invertebrates to low oxygen conditions is
affected by the same factors as those affecting fish re-
sponse.  Table A-15 lists the results of laboratory studies
conducted in Montana and Utah.  It is apparent that re-
sponses of different species, or even the same species from
                          A-66
-------




























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different localities, exposed to different laboratory con-
ditions are highly variable.

Temperature can be extremely critical in determining toler-
ance.  It has been estimated that aquatic organisms at an
environmental temperature of 10°C can withstand a reduced
oxygen concentration about 2.4 times as low as at a temper-
ature of 15.6°C.  Changes in flow are believed to have
similar effects on survival at different oxygen concentra-
tions.  One study demonstrated that a gradual reduction in
oxygen with a water flow of 0.06 ft/sec produced a 50 per-
cent stonefly mortality, while similar conditions with a
water flow of 0.25 ft/sec produced no mortality (Gaufin,
1973).

     Flow Effects:  The physical aspects of the increase in
water volume and velocity are important considerations; how-
ever, these aspects are difficult to separate from the chem-
ical considerations.  Flow and suspended solids are particu-
larly interrelated.  An increase in flow can cause stream
bank scouring that results in an increase in suspended
solids concentrations without an external source of solids.
The effects of bank scour on the biota of a stream is essen-
tially the same as suspended solids entering from surface
runoff.

The increase in velocity alone also affects the biota.
Aquatic plants and animals are pulled off the substrate and
washed downstream.  The type of substrate also affects the
degree of scouring.  Small stones, gravel, or sand sub-
strates are easily disrupted, while large rocks are less apt
to be moved and may provide refuge for mobile aquatic organ-
isms.  The time for recovery or recolonization following a
storm depends on the degree of scouring, the time of year
and type of organisms.  During the active growing season—
spring—more rapid recovery would occur than in the fall.
Although it is impossible to precisely predict how long it
will take a stream to recover, an approximate recovery time
may be from 2 to 4 weeks under normal circumstances.

     Suspended Solids;  Suspended solids  (SS) can have a
detrimental effect on aquatic communities.  The turbidity
caused by SS can inhibit light penetration that is necessary
for photosynthesis, causing a decline in vegetation.  The
abrasiveness of the particles can damage plant bodies, and
as the particles settle, attached vegetation is smothered.
                           A-68
-------
Settleable solids blanket animals, plants and their habi-
tats, either killing the organism or rendering the habitats
unsuitable for occupation.  Suspended solids also serve as a
transport mechanism for pesticides, heavy metals, and other
toxic substances which are readily sorbed onto soil par-
ticles.

Macroinvertebrate and fish species can be directly and indi-
rectly affected by SS.  Changes in habitat may occur because
of destruction of vegetation that eliminate species, or food
sources may be eliminated (Hynes, 1974).  Suspended solids
may directly affect species due to abrasion on delicate mem-
branes and gill structures.

The specific biological effects depend on the nature of the
suspended solids.  If the solids have a high organic con-
tent, a high BOD may be associated with the SS.  In addi-
tion, different particle types have different settling
characteristics and these properties along with the flow
will determine the zone of influence of the entering solids.

It has also been demonstrated that subtle changes in sub-
strate type can affect aquatic organisms.  Rocky substrates
characteristically support the most diverse communities.
One of the main reasons is apparently the availability of
interstitial habitats that are utilized by many species
(Brussen and Prather, 1974) .   Even a small degree of sedi-
mentation can fill these spaces and eliminate or reduce
species populations.  The extent of the change is dependent
primarily on the degree of sedimentation.

EPA has proposed a maximum limit of 80 mg/1 SS in fresh
water (EPA, 1973) .  There is no evidence that concentrations
of suspended solids less than 25 mg/1 have any harmful ef-
fects on fisheries  (EPA, 1973).  Waters containing 25 to 80
mg/1 should be capable of supporting good to moderate fish-
eries, whereas concentrations greater than 80 mg/1 are
unlikely to do so.

     Nutrient Enrichment:  The main effect of nutrient en-
richment is to increase aquatic vegetation.  To what extent
plant biomass will increase is difficult to determine be-
cause the question of what constitutes a limiting concentra-
tion of nitrogen, or phosphorus has never been adequately
answered.  Sawyer (in Harms and Southerland, 1975)  reported
that concentrations of 0.01 mg/1 of soluble phosphorus and
0.30 mg/1 of inorganic nitrogen were sufficent to support
                           A-69
-------
algal blooms in Wisconsin lakes when other environmental
factors were optimum.  Sylvester (in Harms and Southerland,
1975) reported limiting concentrations of 0.01 mg/1 phos-
phorus and 0.2 mg/1 nitrogen for Green Lake in Seattle,
Washington.

For streams, Mackenthus (in Harms and Southerland, 1975)
recommended that total phosphorus concentrations not exceed
0.1 mg/1 (as P) in streams and should not exceed 0.05 mg/1 P
in streams entering a lake or reservoir.  However, a study
by the Federal Water Pollution Control Administration re-
ported that total phosphorus concentrations exceeded 0.05
mg/1 P in 48 percent of the U.S. rivers sampled.  A Public
Health Service study reported that an average of 77 percent
of the stations sampled on U.S. rivers contained at least
0.1 mg/1 P04 (0.03 mg/1 as P) and 60 percent contained ni-
trate concentrations greater than 1.4 mg/1 NO^  (Harms and
Southerland, 1975).

It should also be pointed out that the 0.01 mg/1 of soluble
phosphorus limiting concentration reported by Sawyer (in
Harms and Southerland, 1975) and Sylvester is the detection
limit for the Standard Methods colorimetric analysis custom-
arily employed.  There is little information on the effects
of concentrations below this limit in water quality analy-
ses.  Perhaps the real answer lies in the following state-
ment:  "At this time, no procedure for evaluating nutrient
supplies and detecting growth-limiting factors in lakes and
streams seems to have been developed to the point of general
reliability and usefulness"  (Gerloff, 1969).

Established "threshold" concentrations are best used as a
point of reference to indicate whether a given nutrient con-
centration may present potential or existing problems.  A
single parameter value is not sufficient to determine whether
excessive aquatic growth will occur.

The form the nutrients take is important in determining ef-
fects on water quality.  Ryden et al  (.1972) discussed the
effects of different forms of phosphorus.  It was pointed
out that much of the phosphorus that is exported from water-
sheds may be in biologically unavailable forms, such as
apatite.  The percentage of biologically unavailable forms
is often related to soil type or the soil horizon exposed to
erosion.  Phosphorus in erosion from the lower soil horizon
is to a great extent apatite.  The difference between dis-
solved and particulate forms of phosphorus is also impor-
tant.  Measurements of total phosphorus concentration do not
                            A-70
-------
indicate how much phosphorus is readily available to aquatic
vegetation.  For this reason, dissolved phosphorus measure-
ments are better indicators of immediately available phos-
phorus.

A large percentage of the nutrients associated with nonpoint
source are associated with soil particles.  An immediate al-
gal response following runoff of this type would probably
not occur.  Whether these nutrients would become available
at a later time depends on the chemical and biological
characteristics of the water (see discussion of suspended
solids).   Nutrients entering in a dissolved state may be
more immediately available, although a lag phase of two
weeks was reported between the discharge of storm water into
a lake and a large increase in phytoplankton biomass.  How-
ever, an almost immediate increase in metabolic activity was
noted  (Knauer, 1975).  This delay in biomass increase may be
due to two factors:  (1) the growth rate of the organisms,
and  (2) the time required for biotic recovery following high
flow or storm conditions.

     Toxic Substances:   The toxicity of any substance is de-
pendent on several factors:

     Concentration of the metal

     Type of organism

     Type of metal compound

     Synergistic and antagonistic effects

     Physical and chemical characteristics of the water body

Because of the complexities involved, no single value can be
used as an absolute to predict the effects of a toxic sub-
stance in a water system.  The concentrations and quantities
entering the system are frequently difficult to quantify,
particularly where nonpoint sources are concerned.  It is
also difficult to determine the mixing characteristics and
transport mechanics in the water body.  Assuming these as-
pects can be dealt with, the toxicity of most substances to
aquatic life is not clearly defined.

The majority of the information available on the effects of
toxicity on aquatic organisms is based on bioassay tests
which are carried out under controlled conditions that sel-
dom occur in nature.  This type of information is useful
                           A-71
-------
only as long as the limitations are considered.  To use the
results of bioassay tests as absolutes in determining
whether a given concentration will be harmful in a natural
environment is inappropriate.  Typical bioassay tests do not
measure behavioral modifications that may affect productivi-
ty or the possibility of lowering an organism's resistance
to other adverse impacts, such as disease and/or parasites.
Bioassay information is, however, useful for indicating po-
tential problem areas.

Table A-ll gives an indication of the range of concentra-
tions that have been reported as harmful or non-harmful to
specific aquatic organisms.  The problems involved in mea-
suring toxicity are illustrated by the conflicting results
that have been reported  (Table A-16).  The discrepancies do
not necessarily reflect "right" or "wrong" answers, or even
good or bad testing techniques, but rather the existence of
unmeasured variables in testing procedures.  In addition,
threshold values recommended by EPA are given in the text.
In most cases, these values are well below recorded acute
lethal concentrations and are designed to prevent possible
chronic effects and behavioral modifications.

Although most of the available toxicity information is for
individual rather than combinations of substances, pre-
liminary studies indicate acute toxicities for mixed solu-
tions may be predictable if the TL5Q (50% toxicity level) is
known for the individual substances.  In order to obtain a
predictive three-day Tl^g for mixed effluents the concentra-
tion of each toxic substance found in the effluent was ex-
pressed as the proportion of the expected three-day TL5Q and
these values were then summed to give a predicted Toxicity
Index.  Agreement was found to be good between predicted and
measured results (Lloyd in Biological Problems in Water
Pollution, 1962) .  However, synergistic or antagonistic
effects could greatly affect the accuracy of this procedure.
Table A-17 summarizes synergistic and antagonistic effects
of selected toxicants.

1.   Aluminum

     There is little information on the abundance or toxici-
     ty of aluminum.  Aluminum may have greater toxicity
     than has been assumed  (EPA Water Quality Criteria,
     1972, March 1973).  Its presence in streams may be a
     result of industrial wastes, but a more likely source
                          A-72
-------
                              TABLE  A-16

             REPORTED TOXIC AND NON-TOXIC CONCENTRATIONS

                        OF SELECTED SUBSTANCES
Substance
Concentrations
   (mg/1)	  Exposure
             Organism
                                                          Water Type
Ammonia
      oxic
     Non-toxic
                 0.3-0.4
                 0.3-1.0
                 2.0-2.5
                 3.4
                 1.5

                 4.3
                           trout fry
                           fish
                1-4 days   goldfish
                96 hr TL   bluegill sunfish soft water
                        m" rainbow trout    20 C.
                1 hr
                           roost varieties
                            of fish
                           minnows
Aluminum
     Toxic
     Non-toxic

CadmiTjm
     Toxic
   •0.10         1 week     stickleback
   5.0          5 min.     trout
   5.0          48 hrs     fingerling rain- pH9
                            bow trout
   0.05            -       fish             pH7

   1.0          5 min.     trout
     Chronically
      safe       0.03-0.06
     Reduced re-
      production 0.0005
Chromium
     Toxic
     Non-toxic
   0.01-10      7 days     rainbow trout
   0.01-10      2-6 days   fathead minnows
   0.01-10      96 hrs     bluegill sunfish

                           fathead minnows  hard water
                            bluegill sun-   (.200 mg/1 as
                            fish             Ca COj)

                3 weeks    crustaceans
                            (daphnia)
   17 to 118    96 hrs     fish
   0.05            -       invertebrates
   0.032-6.4       -       algae

   7.1             -       carp
  35.3             -       goldfish
Copper
     Tox
     Non-toxic
                 0.015.3.0
                 0.1-1.0
                 O.OQ6
                                         fish, crusta-    soft
                                          ceans, mollusks,
                                          insects, phyto-
                                          plankton, and
                                          zooplankton
                           most fish
                           fish, crusta-
                            ceans  (Daphnia)
                            hardness  (45
                             mg/1  as
                             Ca Co3)
      Dxic
                 2.5
                 0.05-1.0
                120-136 hr brook trout
                           fish
     Non-toxic
   0.02
   0.25
   0.40
27 days

96 hr
                                         trout
                                         bluegi.lls
                                         bluegills
                           A-73
-------
TABLE A-16
(continued)
REPORTED TOXIC AND NON-TOXIC CONCENTRATIONS
OF SELECTED SUBSTANCES
Concentrations
Substance
Lead
Toxic








Non- toxic


Mercury
Toxic




Non- toxic

(mg/1)

0.2
0.34


0.5-7.0 and
0.4-0.5

482 and 442

0.62
0.7


0.004-0.02
0.01
0.05-0.1
1.0
10-20
0.2

Exposure

-
48 hr TL
in

96 hrs
LC50

96 hrs
LC50
48 hr
3 weeks


-
80-92 days
6-12 days
96 hrs
>10 days
_

Organism

fish
stickleback,
Coho salmon

fathead minnow,
and brook trout

fathead minnow.
and brook trout
trout
minnows ,
sticklebacks

freshwater fish
minnows
fish
fish
fish
tench, carp.
rainbow trout,
Water Type

soft
1000-3000 mg/1
dissolved
solids

soft (20-45
mg/1 CaCo3-

hard
_
soft


-
-
-


_

char, fish, food

Nickel
Toxic


Non-toxic

Reduced re-
production
Zinc
Toxic











Non- toxic



reduced re-
production


5
26-43

0.030

0.095


0.01-0.4

0.5

1.0
3.0

4.0
0.87

33.0

0.13

3.0

0.10



96 hr
LC50
96 hr
LC50
3 weeks

3 weeks


-

3 days

24 hr
8 hr

3 days
96 hr
LC50
96 hr
LC50
20 days

10 days



organisms

fathead minnows
fathead minnows

crustaceans,
(daphnia)
crustaceans,
(daphnia)

young rainbow
trout
fingerling rain-
bow trout
sticklebacks
fingerling rain-
bow trout
rainbow trout
fathead minnows

fathead minnows

brown trout
fingerlings
fingerling rain-
bow, trout
crustaceans
(daphnia)


soft (20 mg/1
as CaCo,)
hard (200-360
as CaCo,)
soft (45Jtng/l
as CaCo )
soft (45Jmg/l
as CaCo,)

-

soft

soft
soft

hard
soft (20 mg/1
as CaCo,)
hard (360 mg/1
as CaCOj)
hard

hard

soft (45 mg/1
as CaCo3)
Source:   McKee  and Wolfe, 1963; EPA, Water Quality  Criteria,
         1972,  March 1973
                           A-74
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                        TABLE A-17

      DETERMINED SYNERGISTIC AND ANTAGONISTIC EFFECTS
                    OF TOXIC SUBSTANCES
Constituent


Ammonia


Cadmium

Chromium

Copper
Cyanide




Lead

Mercury

Nickel

Zinc
   Synergistic
     Effects


High pH, low DO,
cyanide

Zinc, cyanide

Low DO

Chromium, mercury,
zinc, cadmium,
low DO
Low pH, high tem-
perature, low DO,
ammonia, zinc,
cadmium

Low DO

Copper
Copper, low DO,
cyanide
Antagonistic Effects
CO,
Hardness
Hardness (alkalinity),
temperature, dissolved
oxygen, turbidity,
carbon dioxide,  magne-
sium salts, phosphates,
sodium

Copper, nickel,  hard-
ness
Hardness



Hardness

Calcium
Source:  McKee and Wolf, 1963; EPA Water Quality Criteria,
         1972, March 1973
                           A-75
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     is wash water from water treatment plants.  Many of the
     aluminum salts are insoluble and therefore likely to
     settle out rapidly (McKee & Wolf, 1963).  The suspended
     precipitate of ionized aluminum is toxic and concen-
     trations in this form greater than 0.1 mg/1 would be
     deleterious to growth and survival of fish (EPA Water
     Quality Criteria, 1972, March 1973).
2.    Cadmium
     Although many forms of cadmium are highly soluble, the
     carbonate and hydroxide forms are insoluble.  There-
     fore, at high pH, cadmium will tend to precipitate.
     High concentrations of cadmium has been found to occur
     in areas of high population density (Andelman, 1974 -
     in Singis, 1974).  Available data indicate the lethal
     concentration varies from about 0.01 to 10 mg/1, de-
     pending on the test animal, type of water, temperature
     and time of exposure.  Indications are that cadmium
     reacts synergistically with other substances, such as
     cyanide  (McKee & Wolf, 1963).  This metal is considered
     an extremely dangerous cumulative poison.  EPA  (Water
     Quality Criteria, 1972, March, 1973) recommends that
     aquatic life be protected where cadmium concentrations
     exceed 0.03 mg/1 in water with a total hardness above
     100 mg/1 as CaCo3 or 0.0004 mg/1 in waters with a
     hardness of 100 mg/1 or less.
3.    Chromium
     The toxicity of chromium is highly dependent on the or-
     ganism, temperature, pH and synergistic or antagonistic
     effects.  Although fish are relatively tolerant of
     chromium salt, many invertebrates are extremely sensi-
     tive.  There is no conclusive evidence that the hexa-
     valent form is more toxic to fish than the trivalent
     form (McKee & Wolf, 1963).  However, the evidence tends
     to be conflicting and it may depend to a great extent
     on the organism and the compound.  The apparent "safe"
     level for fish  (less than 17 mg/1) is moderately high,
     and the recommended EPA  (Water Quality Criteria, 1972,
     March,  1973) upper limit of 0.05 mg/1 was selected in
     order to protect mixed aquatic populations.
                          A-76
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4.    Copper
     Copper salts occur in surface water only in trace
     amounts and their presence in concentration above 0.05
     mg/1 is generally considered a result of pollution
     (McKee & Wolf, 1963).  Although the chloride, nitrate
     and sulfate of the cuprous ion are soluble in water,
     the carbonate, hydroxide, oxide and sulfide are not.
     Therefore,  at a pH of 7 or above, the cupric ions will
     rapidly precipitate  (McKee & Wolf, 1963).

     In hard water, copper toxicity is reduced by the pre-
     cipitation of copper carbonate or other insoluble com-
     pounds.  Synergistic reactions are believed to occur
     between copper and chlorine, zinc, cadmium and mercury.
     In contrast, evidence suggests copper decreases the
     toxicity of cyanide  (McKee & Wolf, 1963).

     The factors influencing the lethal toxicity of copper
     to  fish include hardness, dissolved oxygen, tempera-
     ture,  turbidity, carbon dioxide,  magnesium salts and
     phosphates  (EPA Water Quality Criteria, 1972, March
     1973).   The implications that copper is particularly
     toxic  to algae and mollusks should be considered for
     any given body of water; however, the criteria (safe-
     to-lethal ratios 0.1 to 0.2) that apply to fish will
     protect these organisms as well.   The safe-to-lethal
     ratio  of 0.1 should be multiplied by the 96-hour LC5Q

     of the most sensitive important species in the locality
     to determine a recommended safe concentration of cop-
     per to protect aquatic life (EPA Water Quality Cri-
     teria,  1972, March 1973).

     Cyanide

     The toxicity of cyanide is highly dependent on pH.  As
     the pH decreases, toxicity increases; however, it has
     been reported that in the pH range of 6.0  to 8.5, there
     is little effect on toxicity.   In natural  water,  cyan-
     ides deteriorate or are decomposed by bacterial action.
     Degradation is unaffected by temperatures  in the range
     from 10° to 35°C but is greatly reduced at lower or
     higher temperatures  (McKee & Wolf, 1963).

     The toxicity of cyanide is increased by elevated tem-
     peratures (a 10°C increase produces two- to three-fold
                         A-77
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     increases in toxicity),  low dissolved oxygen, zinc and
     cadmium.   The toxicity of cyanide is lower for in-
     vertebrates than for fish (McKee & Wolf, 1963).
6.    Iron
     Iron is less toxic than most other heavy metals.  Ex-
     tremely high concentrations in unbuffered water can
     lower the pH to toxic levels, but the deposition of
     iron hydroxide precipitate is more likely to harm fish
     by coating gills or smothering fish eggs.  Ninety-five
     percent of U.S. water supporting good fish life have
     iron concentrations of 0.7 mg/1 or less  (McKee & Wolf,
     1963).
7.    Lead
     The carbonate, hydroxide and sulfate salts are rela-
     tively insoluble; therefore, lead generally settles out
     fairly rapidly except in soft waters.  Lead toxicity
     increases with a reduction in dissolved oxygen.  EPA
     (Water Quality Criteria, 1972, March, 1973) recommends
     that the concentration of lead should not exceed 0.03
     mg/1 at any time or place in order to protect aquatic
     life.
8.    Mercury
     Although elemental mercury is insoluble in water, many
     of the salts are quite soluble.  Mercuric ions are con-
     sidered highly toxic to aquatic life  (Table A-16).  The
     toxicity of mercuric salts is increased by the presence
     of trace amounts of copper (McKee & Wolf, 1963).

     There is not sufficient data available to determine the
     levels of mercury that are safe for aquatic organisms
     under chronic exposure.  Since experiments on sublethal
     effects are lacking, the next most useful information
     available is on the lethal effects following moderately
     long exposures of weeks or months.  As exposure  time
     increases, lower concentrations of mercury become
     lethal.  Data are not available on the residue levels
     that are safe for aquatic organisms  (EPA Water Quality
     Criteria, 1972, March 1973).  According to the Food and
     Drug Administration, mercury residues should not exceed
     0.5 micrograms per gram of total mercury in edible
                          A-78
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     portions of fresh water fish.  EPA (Water Quality Cri-
     teria, 1972, March, 1973)  suggests that this level be
     the guideline to protect predators in aquatic food
     chains.
9.    Nickel
     Although nickel as a pure metal is insoluble in water,
     many nickel salts are highly soluble.  Nickel is one of
     the least toxic metals.  Although 0.8 mg/1 has been
     reported as lethal to sticklebacks, fish have been
     found living in water with concentrations of 13-18 mg/1
     of nickel (McKee & Wolf, 1963).  The safe-to-lethal
     ratio for nickel is 0.01 for the protection of fish.
     This application factor should be applied to the 96-
     hour LC5Q °f *-he most sensitive important species in
     the locality to determine the recommended concentration
     of nickel safe to aquatic life (EPA Water Quality Cri-
     teria, 1972, March 1973).
10.   Zinc
     Zinc salts such as zinc chloride and zinc sulfate are
     highly soluble in water; however, salts such as zinc
     carbonate, zinc oxide and zinc sulfide are insoluble in
     water.  Therefore, the compound present is important in
     determining whether zinc will settle out or remain in
     solution.

     Zinc is toxic to aquatic organisms.   The acute lethal
     toxicity of zinc is greatly affected by water hardness.
     The sensitivity of fish to zinc varies with species,
     age and condition of the fish, as well as with the
     physical and chemical characteristics of the water.
     Acclimatization to zinc has been reported for some
     fish.   Calcium is especially antagonistic to zinc
     toxicity.   In soft water, zinc and copper react syner-
     gistically, but this does not hold in hard water.
     Toxicity is also thought to increase in the presence of
     cyanide and as dissolved oxygen concentrations de-
     crease.  The safe-to-lethal ratio for zinc (0.005), if
     multipled by the 96-hour LC,-Q of the most sensitive
     important species in the locality, will determine the
     recommended concentration of zinc safe to aquatic life
     (EPA Water Quality Criteria, 1972, March 1973).
                          A-79
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     Sublethal Effects;  In addition to direct toxicity,
sublethal effects must also be considered.  If a substance
causes avoidance, interference with sensory mechanisms, or
prohibits reproduction, aquatic organisms gradually will be
eliminated, even though dramatic die-offs do not occur.

Young Atlantic salmon are reported to avoid copper and zinc
at concentrations one-fiftieth the incipient lethal level.
Low levels of copper have also been reported to interfere
with odor cues necessary for salmon to return to home
streams for spawning (Sutterlin, 1974).

Avoidance behavior may be beneficial if a substance is tem-
porary and localized and can prevent sudden die-offs of
mobile organisms.  However, where chemical senses are inter-
fered with, organisms may be restricted in feeding and re-
productive processes which may cause gradual reduction or
total elimination of species.

     Road Salts:  The biological effects of road salts on
aquatic organisms have received little attention.  One study
reported direct and indirect effects on lake benthic or-
ganisms.  The increase in salinity directly eliminated
dipteran larvae, and the decrease in oxygen concentration
that occurred because of the density changes eliminated
several oligochaete species  (Judd, n.d.).

The effects of adding salts to freshwater can be predicted
to a great extent on the basis of reactions of freshwater
organisms to marine and estuarine environments.  Freshwater
organisms cannot survive in salt water environments because
of the change in osmotic pressure that affects fluid bal-
ance.  Although specialized species that can tolerate wide
ranges of salinity exist, adaptation to the intermittent
input of salt associated with nonpoint source runoff would
be unlikely.  Chloride concentrations in freshwater support-
ing good fish life are below 9 mg/1 in 50 percent, and below
170 mg/1 in 95 percent, of the waters  (McKee & Wolf, 1963).
Concentrations reported as harmful to fish are presented in
Table A-18.
                          A-80
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                         TABLE A-18

         CONCENTRATIONS OF CHLORIDE HARMFUL TO FISH


     Cl Concentrations  (mg/1)            Type of Fish

             400                         Trout

            2000                         Some fish

            4000                         Bass, Pike, Perch

          4500-6000                      Carp eggs

          8100-10,500                    Small Bluegills


     Source:  McKee & Wolf, 1963


Analysis of Water Quality Data to Determine Nonpoint Problems

In many areas, the extent and severity of nonpoint problems
is often unknown.  This is usually due to past concentration
on point sources and inadequate water quality data.  This
obviously makes it extremely difficult to set priorities and
develop a coherent strategy for analyzing nonpoint problems
and establishing controls.

It is often possible to use existing water quality data to
help focus on specific pollutants and certain watersheds and
stream segments where nonpoint problems appear most severe.
The remainder of the 208 nonpoint program can then concen-
trate on the major problems that have been identified.  Un-
doubtedly, additional data collection will also be required
to better define existing nonpoint problems.  This section
covers these two crucial areas of nonpoint analysis; analy-
sis of existing data and collection of additional data.  The
presentation is organized by the following topics:

     Analysis of Existing Data:  An Example

     Use of Steady-State Models in Nonpoint Source Analysis

     Analysis of Biological Data for Nonpoint Analysis

     Development of a Nonpoint Source Sampling Program
                          A-81
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     Analysis of Existing Data:  An Example;  In areas where
a good water quality network has been in existence for
several years, a surprisingly large amount of information on
the location and severity of nonpoint problems can be ob-
tained by proper analysis of the data.  The objective of
this subsection is not to detail the techniques for nonpoint
analysis but merely to indicate the types of analyses which
may be used to shed light on major nonpoint problems.  A
recent study on the Passaic River in New Jersey (Berger/Betz,
1975) is used as an example of what innovative evaluation of
existing data might yield.

1.   The Setting

     The example used was taken from a recent water quality
     management study of the Northeast New Jersey metropoli-
     tan area (Berger/Betz, 1975).  The major stream in the
     study area is the Passaic River, a slow moving stream
     which is heavily used for water supply and waste as-
     similation throughout its length.  The analysis which
     follows was for the free flowing portion of the stream;
     the estuary portion was not included in the analysis
     because of the magnitude of combined sewer overflows
     into the estuary, insufficient data, and the complica-
     tions of data interpretation caused by tidal fluctua-
     tions.

     The Freshwater Passaic covers a drainage area of 806
     square miles and is the third largest drainage area in
     the State of New Jersey.  Average annual rainfall over
     the area is about 47 inches.  The majority of the
     Freshwater Passaic is geographically located in the New
     England Upland Province.  Topography is generally flat.
     Population in the basin is over 600,000  (population
     density over 700 people per sq mi).  Land uses in the
     basin are:
               1970 Land Use            % of Total Area

          Single Family Residential          23.5
          Multi Family Residential            1
          Industrial                          3.5
          Commercial                          1.5
          Public and Quasi Public             5
          Conservation, Recreation
          and Vacant                         65.5
                          A-82
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     The analysis was structured to gain information on
     three broad types of nonpoint sources.  The following
     quotation (Berger/Betz, 1975) defines the three cate-
     gories :

          "An important distinction of nonpoint sources
          exists among storm-activated sources, continuous
          sources and erratic sources.  Storm-activated
          sources involve contaminant loads derived from the
          land surface and delivered to the stream system by
          surface runoff.  These pollutant loadings can
          result in transient water quality problems during
          storm periods, and also can contribute to long-
          term problems due to the settling out of material
          in benthic deposits.  Annual nonpoint source pol-
          lutant yields tend to be dominated by loadings
          derived during storm periods—although these
          loadings are not necessarily most important in
          terms of problems created.

          "Continuous nonpoint sources generally involve
          contamination of the groundwater reservoir which
          feeds the stream system more or less continuously
          over time and space.  Continuous sources tend to
          have relatively less impact on water quality dur-
          ing storms than during nonstorm periods, due to
          the much greater dilution of effluents during
          storms; thus, continuous nonpoint sources are
          analyzed primarily as a low-flow problem.

          "Erratic sources, such as unauthorized dumping and
          accidental spills, are difficult to evaluate
          without direct monitoring of individual source
          area.  Their impact is usually established only on
          an average long-term basis, usually in combination
          with other types of sources."

2.    The Analysis

     BOD, dissolved oxygen and sediment data were deemed
     adequate for analysis; heavy metal and nutrient data
     were extremely sparse and not appropriate for rigorous
     analysis.  Monthly parameter values were available on
     several stations located along the freshwater Passaic
     and its  tributaries.  A continuous recording station
                          A-83
-------
     existed at the most downstream station,  yielding daily
     data on DO,  temperature,  pH and conductivity.*  Data
     from a summer survey conducted to calibrate a low flow
     model were also available.

     The analysis consisted of mass balance techniques,
     annual load computations  and plotting of data.  The
     analysis was divided into four separate techniques,
     each used for defining different portions of the non-
     point source problem:

          Low Flow Mass Balance

          Annual BOD Loads

          DO Response to Storm Loadings

          Annual Sediment Loads

     The purpose of each technique, parameters analyzed,
     etc., are summarized in Table A-19.

3.    The Results

     Details of the analysis techniques can be found in the
     original report (Berger/Betz, 1975).   The results of
     the analysis yielded the  following conclusions:

     a.   Based on the low flow mass balance, nonpoint
          problems occurring during low flow conditions
          (benthic deposits, polluted groundwater inflow,
          unreported point sources) were prioritized.
          Various sections of  the river and its tributaries
          were identified as having especially severe prob-
          lems.  The results were used to better define a
          nonpoint source sampling program.

     b.   The annual BOD load calculations, which tend to be
          dominated by storm period loads, were used to
          locate areas having significant storm-activated
* Hourly data was not utilized in the analysis, but it was
  available through USGS.
                          A-84
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                         TABLE A-19

       EXAMPLE TECHNIQUES FOR ANALYZING EXISTING DATA
                FOR NONPOINT SOURCE PROBLEMS
Technique

Low Flow Mass
Balance
Condition

Low Flow
Data Analyzed   Purpose
Annual BOD
Loadte
Dissolved
Oxygen
Response
to Storm
Loadings
Annual
Sediment
Loads
All flow con-
ditions used
to calculate
annual load
Storm Condi-
tions
All flow con-
ditions used
to calculate
annual loads
CBOD & NBOD*
values from
summer survey
data collected
for low flow
model calibra-
tion

CBOD values
published for
several sta-
tions in USGS1
annual "Water
Quality Re-
cords"
To identify areas
with significant
steady-state or
continuous non-
point source
problems.
To identify areas
with abnormally
high nonpoint BOP
loads.  This is
strongly related
to storm runoff
loads as opposed
to steady-state
nonpoint sources.
Daily DO values To determine tran-
published for
the most down-
stream station
in the network
sient impact of non-
point sources on DO
and make preliminary
determination of
what causes DO depres-
sion after storm.
Sediment values To test hypothesis
for several     of significant
stations in     benthic deposition.
USGS'  annual
"Water Quality
Records"
* CBOD B carbonaceous BOD; NBOD B nitrogeneous BOD

Source:  Berger/Betz, 1975
                    A-85
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     sources.   Two stream segments were identified with
     extremely high nonpoint loads, it was suspected that
     discrete  sources,  such as spills, material storage
     yards,  bypasses from sanitary sewers, pump stations and
     treatment plants,  may be the cause of some of the high
     readings.  A sampling program was designed to collect
     additional data on the significant problem segments.
     It is hoped that future sampling will identify discrete
     sources,  which are usually easier to control than
     distributed runoff sources.

     c.   Analysis of daily dissolved oxygen values at the
          last downstream station revealed that DO levels
          increased shortly after the start of a storm but
          declined over a period of several days to below
          the  level which prevailed at the beginning of the
          storm (plots of this phenomena have already been
          presented in Figure A-10).   The DO response
          appeared to be explained by assuming that the DO
          was  depressed by organic material which was washed
          into the stream by runoff and by the scouring of
          benthic deposits.  Because of the characteristics
          of the Passaic (extremely slow velocities) it is
          unlikely that benthic deposits can be sufficiently
          controlled by runoff control measures to signifi-
          cantly alleviate the post-storm DO depression.

     d.   The  sediment mass balances were computed to gain
          perspective on the benthic deposit accumulations.
          Analysis indicated that nearly half of the annual
          sediment input to the main river segment settles
          out  rather than leaves the basin.

     Use of Steady-State Models in Nonpoint Source Analysis:
Steady-state water quality models cannot adequately handle
transient events associated with some nonpoint sources.
However, use of steady-state models can aid in the assess-
ment of several nonpoint sources.  As indicated in the
previous section, the actual data collected for model cali-
bration can be used for mass balances  (in the example given
in the previous section, this technique located areas of
significant steady-state loads).

Nonpoint sources which may be handled by steady-state model-
ing include:
                          A-86
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            Source

     Landfill leachate

     Marshes
     Pervious lagoons
     Salt water intrusion
     Areas of septic tank
     malfunctioning
     Acid mine drainage
   Typical Parameters

BOD/DO, nutrients, heavy
metals
BOD/DO, nutrients
BOD/DO, nutrients
Chlorides

BOD/CO, nutrients
Heavy metals
These pollutant sources can be handled in steady-state
modeling by adjusting certain modeling parameters to reflect
loads from nonpoint sources.  Benthic loads are generally
handled specifically in the benthic demand components of the
model.  Distributed sources, such as septic tank areas,
marshes, etc., can be handled by adjusting the incremental
runoff loads in the model.  Sources such as lagoons and
landfills may be addressed either as a point source or a
distributed source, depending on the characteristics of the
groundwater flow system and the length of the model reaches.

Considerable skill and experience is needed in adapting and
calibrating steady-state models to accurately reflect actual
conditions.  It is possible to miscalibrate a model and
develop water quality predictions which are grossly in
error.  The only safeguard to prevent this from happening is
to collect adequate calibration data and perform model
calibration with experienced modelers.

     Analysis of Biological Data:  The assessment of bio-
logical data offers a tool for the investigation of nonpoint
sources which is often neglected or under-utilized.  Reli-
ance on only chemical and physical data does not yield a
complete picture of water quality.  Because of the general
lack of sufficient chemical data and the complexity of
interpreting physical and chemical data as they relate to
the health or quality of a stream, it may be cost effective
to place greater emphasis on biological parameters.

Aquatic organisms and communities can be used as natural
pollution monitors.  When an aquatic community undergoes a
stress, such as pollution, the community structure can be
affected.  This change can be monitored and the long-term
effects can be measured and analyzed.  Because aquatic or-
ganisms respond to their total environment and reflect long-
term conditions, they can often provide a better assessment
                          A-87
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of stream quality and environmental damage than can other
monitoring methods.  Some organisms tend to accumulate or
magnify toxic substances, pesticides, radionuclides and a
variety of other pollutants.  Organisms also can reflect the
synergistic and antagonistic interactions of point and
nonpoint source pollutants occurring within a specific re-
ceiving water system.

Chemical analyses can only indicate the water quality at the
time the sample is collected, and unless extensive sampling
is done, variation in different areas of the water will not
be determined.  Even if adequate chemical data were avail-
able, the problem would still remain:  interpret its signi-
ficance to aquatic ecology.  For example, suppose a stream
which demonstrates a sharp DO decline to 3 mg/1 after storm
periods (rainfall greater than 0.5 inches).  This level is
generally maintained for 6 hours; DO then recovers to 5.5
mg/1.  Apparently, storm runoff is causing the DO drop, but
is this drop causing a problem?  If a biological survey
indicates that the fish and other aquatic species desired
for the stream are relatively unaffected then the answer may
be negative.*  At least the problem could not be termed
critical and the remaining nonpoint program could be modi-
fied accordingly.

In evaluating the condition of an aquatic system, many
factors must be considered.  The available information must
be evaluated on the basis of habitats surveyed, season, and
flow regime.  The guidelines discussed in the following
paragraphs must be used with the above point in mind.

Biological sampling programs for the detection of nonpoint
problems are presented in a later section of this appendix.
The following discussion assumes that the data has already
been collected and must be evaluated.

The concept of indicator, or sensitive organisms is fre-
quently employed in evaluating water quality.  While this
concept, in conjunction with community structure, is the
* The storm runoff could be causing deleterious loads of
  nutrients or heavy metals which cause problems down-
  stream.  This is neglected in the above example.
                          A-88
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basis for biological surveys, a number of limitations must
be acknowledged when evaluating water quality on the basis
of the presence or absence of certain organisms.

First, many factors besides water quality affect the distri-
bution of organisms.  In streams, velocity and substrate are
two important factors.  Although the presence of certain
organisms usually indicates good water quality, their ab-
sence may be due to factors other than poor water quality
(Hawkes, 1974).  An English study, Report of the River Pol-
lution Survey, found that 98% of the length of a fast-moving
stream was classified as first class quality, biologically
and chemically.  Only 6% of the length of a slow-moving
stream was first class biologically and chemically, while
65% was ranked as third class biologically but first class
chemically (Hawkes, 1974).  The difference in biological
condition was due to unsuitable habitats, not chemical or
physical water quality.

A second limitation of indicator systems is that they have
been developed on the basis of organic pollution, which may
not always be the main consideration for nonpoint source
analysis.  Organisms differ in their respective tolerances
to different forms of pollution.  For example, stoneflies
which are considered the most intolerant of organic pollu-
tion were found to be among the most tolerant organisms in
heavy metal-polluted Welsh rivers (Hawkes, 1974).  However,
suspended solids and BOD, two parameters associated with
organic pollution, are also concerns in nonpoint source
pollution.  Therefore, existing information on organisms
tolerant of organic pollution can be applicable to nonpoint
source pollution.

As long as the limitations of the information are realized,
the concept of indicator organisms can be very useful in
assessing the effects of nonpoint source pollution.  Al-
though the presence or absence of a single species does not
define water quality, the presence of large numbers of cer-
tain species, or absence of whole groups of organisms, can
be indicative of water quality conditions.

Palmer  (1969) lists 80 algae species tolerant of organic
pollution.  The list was part of a compilation based on 269
reports from 165 authors.  Rankings were determined by
assigning a score of 1 or 2 for each species reported as
tolerant to organic pollution.  A 2 was assigned if the
species was reported to tolerate large amounts of organic
                          A-89
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pollution.  Hart and Fuller (1974) listed invertebrate
species found at pH values less than 4.5 and greater than
8.5 and adverse oxygen and BOD conditions (DO less than 4
mg/1 and BOD greater than 5.9 mg/1).  Use of the species
lists contained in the cited publications can aid in assess-
ing water quality conditions.

In addition to the concept of indicator organisms, community
structure is also considered in evaluating aquatic systems.
Characteristically, aquatic systems with good water quality
have a greater number of species than systems with poorer
quality water.  There are some exceptions to this pattern,
but it generally holds true.  Species distribution is also
important.  Polluted waters are usually dominated by a few
species with numerous individuals while other species present
have very few individuals.  Good quality waters usually have
a more equal distribution of individuals per species.

Numerous methods have been devised for analyzing biological
data.  The following is a classification for streams that
provides a means for general and specific evaluation.  The
classification is based upon combining aspects of community
structure with the indicator organism concept.  Although
there are exceptions to this pattern, it provides a general
overview of expected conditions.

The biological organisms are divided into the following
seven categories:
     Category

        1
        2

        3

        4
               Description

Blue-green algae and the green algae
genera Stigeoclonium, and Tribonema; the
bdelloid rotifers plus Cephalodella
megalocephala and Proales decipiens

Oligochaetes, leeches and pulmonate snails

Protozoa

Diatoms, red algae, and most of the
green algae

All rotifers not included in column one,
plus clams, prosobranch snails, and tri-
cladid worms
                          A-90
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        6           All insects and Crustacea

        7           All fish
After the data have been categorized, the sampling stations
thought to be affected by nonpoint source pollution are com-
pared to an unaffected station or the control; or compared
to a standard that has been set up for a geographical region.

The number of species in each category for the control sta-
tion or standard is set as equal to 100%.  The percentage of
species for each of the categories is then computed for the
affected stations.  For example, if the control station had
10 species in Category 1 and the impact station had 5 spe-
cies in Category 1, the value for the impact station would
be 50%.  The resulting patterns are defined as follows:

     Healthy:  The algae are mostly diatoms and green algae,
     such as Cladophora crespata and glomerata, and the
     insects and fish are represented by a great variety of
     species.  There are numerous protozoa, but they do not
     fall into a set pattern.

     Categories 1 and 2 tend to vary greatly, depending on
     ecological conditions in the area.  Categories 4, 6 and
     7 are all above the 50% level.

     Semi-healthy:  The pattern is irregular, indicating the
     balance found in a healthy station has been disrupted
     but not destroyed.  Often a single species will be
     represented by a disproportionately large number of
     individuals.  This condition may be defined as follows:

     1.   Either or both categories 6 or 7 below 50%, and
          categories 1 or 2 under 100%.

     2.   Either category 6 or 7 below 50%, and categories
          1, 2 and 4 100% or over:  or categories 1 and 2
          100% or over and category 4 having large numbers
          of some species.

     Polluted:  The overall balance of the community is up-
     set.  However, conditions are favorable for some spe-
     cies in categories 1 and 2.  This conditions is defined
     as follows:
                          A-91
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     1.   Either or both of categories 6 and 7 are absent,
          and categories 1 and 2 are 50% or better.. .

     2.   Categories 6 and 7 are both present, but below
          50%; then categories 1 and 2 must be 100% or more.

     Very Polluted:  Conditions are definitely toxic to
     plant and animal life, with many groups absent.  This
     condition is defined as follows:

     1.   Categories 6 and 7 are absent, and category 4 is
          below 50%.

     2.   Category 6 or 7 is present, then 1 or 2 is less
          than 50%.

Although this level of information is not available in many
cases, this classification provides an overall picture of
the types of organisms and general community structure
characteristic of different ecological conditions (Patrick
1949).

     Development of a Nonpoint Source Sampling Program;
Additional data will be required in almost all 208 areas to
further define nonpoint source problems.  The data may be
used for problem assessment, model calibration, etc., and
thus is critical to adequate nonpoint source evaluation.
Since the time span of initial 208 work is relatively short,
it is unlikely that all, or even most, of the questions con-
cerning nonpoint pollution can be answered by additional
data; a long-term sampling program based upon "best guess"
priorities is probably the best strategy for sampling.

The following paragraphs do not present the methodology for
developing a nonpoint sampling program.  Rather, important
considerations are reviewed and an overview is presented
which may help in establishing study area specific programs.

1.   The Nonpoint Source Sampling Framework

     A partial listing of major nonpoint sources is pre-
     sented in Table A-20.  This list includes storm-acti-
     vated sources and sources which operate more or less
     independently of hydrologic conditions.  The analysis
     of these sources involved two elements:
                          A-92
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                         TABLE A-20

              MAJOR NONPOINT POLLUTANT SOURCES


Surface Runoff  (including intermittent point sources)

     Combined sewer overflows
     Other urban runoff  (including storm sewers and sanitary
          sewer bypasses)
     Suburban runoff  (including storm sewers and sanitary
          sewer bypasses)
     Runoff from other developed land—e.g., highways
     Agricultural runoff:  cropland
     Pastureland, feedlots, other ag. land
     Runoff from construction sites
     Silviculture and surface mining operations

Sources Involving Groundwater Contamination

     On-site waste disposal systems
     Leachate from landfills and other residual waste
          disposal activities
     Agriculture, including agricultural specialities
     Acid mine drainage
     Lagoons (municipal and industrial)
     Spray irrigation

Factors Affecting Water Quantity

     Salt water intrusion
     Hydrographic modifications:
          Impoundment s
          Channelization
          Impervious surface

Miscellaneous Sources

     Unauthorized discharges, dumping
     Accidental spills, overflows,  leakages (e.g., lagoons,
          pipelines)
     Port operations
     Recreational water use
                             -93
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     a.    Pollutant  generation

     b.    Receiving  water  response

     Generally,  neither  the  nature  nor  extent  of  water
     quality  problems  resulting  from  storm-period pollutant
     loadings is well  defined.   The sampling program must
     therefore carefully balance the  needs  of  pollutant
     generation and  receiving water response.

     Pollutant generation  refers to the quantity  of  pollu-
     tants yielded to  the  surface water system, including
     the  timing of pollutant loads  and  their relationship to
     hydrologic conditions.  Receiving  water response refers
     to the actual problems  created by  nonpoint source
     loadings in surface waters. Analysis  of  receiving
     water response  must consider:

     a.    Pollutant  routing  under various  flow conditions

     b.    In-stream  processes  such  as:

          decomposition
          photosynthetic activity
          reaeration
          precipitation  of materials  into  the  benthos

     c.    Characteristics  of all water  bodies  being  affected
          by  a given nonpoint  source.

     It appears that a cost-effective approach to nonpoint
     source impacts  focus  upon the  limiting conditions  for
     design of control measures.  That  is,  although  a given
     pollutant source in a given basin  may contribute to
     several  different types of  problems,  detailed quanti-
     tative analysis need  be provided only for those sources
     causing  the problems.  These sources  will require  the
     most stringent  control  measures.  An  extremely  impor-
     tant goal of the sampling program and initial analysis
     will be  to identify these conditions,  and thus  to  nar-
     row  the focus of subsequent activities.

2.    The  Type Problem Approach to Nonpoint Source Questions

     The  "Type Problem Approach" is suggested  as  an  orderly
     and  logical method  of investigating nonpoint source
                          A-94
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effects.  The major nonpoint pollutant sources in Table
A-20 can be conveniently organized into four major
classes of problems:

a.   General non-storm quality factors

b.   Site-specific nonpoint sources

c.   Transient storm problems

d.   Long-term storm effects

The four separate types of problems can be attached by
four supplementary measurement programs which, taken
together, provide a unified overview of the major pos-
sible categories of problems.

a.   General Non-storm Quality;  General non-storm
     quality factors include geochemically-related
     natural background changes and changes attribut-
     able to man's activities.  Quality problems may be
     related to dissolved oxygen, nutrients or toxic
     materials.  A low flow sampling program for
     steady-state model calibration (a usual component
     in many 208 studies) will provide the basic input
     to the definition of regionalized incremental
     runoff quality factors.  Major deviations in
     quality not attributable to point sources will
     serve to flag that area as a nonpoint source
     special interest area.

     The role of benthic demands on water quality is
     generally not well established.  The low flow
     sampling should include a general characterization
     of the nature and depth of sediments at each loca-
     tion.  The objective is to produce a benthic map.
     Benthic demands appearing in the modeling analysis
     will be of special concern.  Such areas should be
     subsequently investigated in detail through field
     surveys to verify their existence, extent, depth,
     uptake rate and other characteristics.

b.   Site-Specific Sources:  Site specific nonpoint
     sources are those which have clearly defined
     source areas such as:
                     A-95
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Landfills
Spray irrigation fields
Lagoons of various types
On-site disposal areas, i.e., septic tank con-
centrations

To a significant degree such locations are amen-
able to a regulatory action.  Their actual impact
on the receiving water quality is often not well
known, especially for sites installed before the
current complex environmental monitoring require-
ments were adopted.  A major requirement of the
nonpoint work element is the establishment of
nonpoint source priority lists.  The case of land-
fills is illustrative of the priority dilemma.

Landfills are generally too numerous in the study
area to be considered individually in any data
effort.  There is usually little information as to
whether specific landfills have a significant
impact on surface water quality.  The magnitude of
the problem should be determined, as suggested
below, along with its hydrogeologic and seasonal
variations.  The same types of questions apply to
other site-specific sources.

Assuming that monitoring all site-specific sources
is not possible, it is proposed that a sampling
approach involving the monitoring of the seasonal
performance of a number of representative and
critical site-specific sources be adopted.  Ques-
tions concerning the seasonal variation of loads
as they directly affect surface water quality can
be answered by sampling from high water spring
conditions through dry summer conditions.

This approach would provide assistance in develop-
ing pollutant generation relationships and in
identifying current and potential surface and
groundwater quality problem areas.  It would also
be an important aid in establishing priorities for
the extent of the particular problem and the
allocation of the 208 project resources to be
devoted to their solution.
                A-96
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c.   Transient Storm Problems:  Transient storm prob-
     lems may be investigated in terms of three broad
     effects:

     dissolved oxygen variations
     nutrient, toxics and heavy metals washoff
     the integrated effects on the major downstream
          water bodies (e.g., estuaries)

     Dissolved oxygen levels are of concern because
     they exert an intermediate effect on a stream's
     fishery resources.  During a storm, two oxygen
     forces are activated.  The first is the effect of
     cloud cover in reducing photosynthesis.  This may
     be especially important when clouds persist for
     several days with slow moving storm systems.  A
     high initial biomass to flow ratio would aid in
     the oxygen depression.  The second effect is the
     elevation of dissolved oxygen levels due to in-
     creased reaeration from raindrop impact and in-
     creased turbulence due to higher flows.

     The relative magnitude of these two forces deter-
     mines whether the net effect is an elevation or
     depression of dissolved oxygen levels.  The rela-
     tionship of these effects to critical levels is
     not well documented for most streams.  It is pro-
     posed that a sampling program involving a recon-
     naissance level study of dissolved oxygen levels
     during storm events on area tributaries be adop-
     ted.  This is an important part of problem assess-
     ment because, generally, it is not even known
     whether there is indeed a problem that must be
     addressed by 208 planning.

     The establishment of pollutant-generation rela-
     tionships is generally a central aspect of the 208
     approach.  Washoff rates for nutrients, toxics and
     heavy metals must generally be established for
     various land uses.  The storm sampling should in-
     clude sampling for important parameters; this will
     permit a limited verification of the SWMM/STORM
     pollutant-generation methodology.

     The assessment of tributary storm effects on estu-
     aries or other major downstream water bodies is an
     extremely complicated task because it must bridge
                     A-97
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the gap between the process of pollutant genera-
tion and the actual amount of pollutants being
delivered by the tributaries into their receiving
waters.

Two approaches to this problem may be appropriate.
Within the framework of the reconnaissance samp-
ling network, stations should be chosen to repre-
sent segments upstream and downstream from rela-
tively flat uniform reaches having no tributary
inputs.  The net difference in the stream load
across the reach would represent the effect of
possible sediment resuspension, sediment depo-
sition, or bank and channel scouring.  The second
approach would involve an analysis of the dif-
ferences between the SWMM/STORM-generated pollu-
tant loads and those that were actually measured
in the course of the sampling program.

A major potential problem in the verification of
the modeling results is that the inherent errors
in the pollutant generation algorithms have the
potential of being of the same or greater magni-
tude than the effect that the modeling process is
trying to detect.  This means that interpretation
of the modeling results will have to be made
judiciously.  A major accomplishment would be the
development of reliable relationships between pol-
lutant generation and pollutant delivery.  This
would permit modifications of SWMM/STORM outputs
to reflect more accurate water impacts.

Long-Term Storm Effects - Dissolved Oxygen:  Long-
term residual effects of storms may have a signi-
ficant effect on steady-state water quality con-
ditions through the mechanism of benthic demand.
The exact role of benthic demand in controlling
water quality is not well defined on most of the
study area streams.

Benthic deposits may be particularly troublesome
behind river impoundments or slow, flat portions
of the river.  If benthic problems are suspected,
the sampling program should investigate in detail
the oxygen relationships in impoundments.  This
involves systematic measurement of dissolved
                A-98
-------
          oxygen and the use of light and dark respirometers
          to measure the benthic oxygen uptake rate.   Mea-
          surements should be made before and after storms.
          This will help determine long-term stream re-
          sponses to nonpoint pollutants washed in from
          tributary streams.  Data should also be collected
          during relatively stable streamflow sequences to
          determine possible changes in benthic demand due
          to steady-state accumulations.  This program
          should help resolve questions concerning the
          relative effects of storm washoff, bottom resus-
          pension and steady-state accumulation.

          Another sampling program may be necessary to de-
          termine the relative importance of diurnal  dis-
          solved oxygen variations.  Many times,  steady-
          state modeling without accounting for diurnal
          effects may be a gross misstatement of  the  on-
          going stream processes.  If diurnal problems are
          suspected, there is a need to establish the rela-
          tive importance of the periphyta, rooted aquatics,
          in controlling the phyotosynthesis/respiration
          balance in local streams.

3.    Biological Monitoring

     Biological monitoring provides an effective  means by
     which to evaluate water quality because biological data
     are generally the best indicators of the overall con-
     ditions of a water body.  This type of monitoring seems
     especially appropriate when one considers that water
     quality standards are partially designed to  protect
     biological organisms.

     For purposes of biological monitoring, a station will
     normally encompass areas, rather than points, within a
     reach of river or area of lake, reservoir or estuary
     that adequately represent a variety of habitats  typ-
     ically present in the body of water being monitored.
     Unless there is a specific need to evaluate  the  effects
     of a physical structure, it will normally be advisable
     to avoid areas which have been altered by a  bridge or
     weir, are located within a discharge plume,  etc.  Thus,
     biological sampling stations may not always  coincide
     with chemical or sediment stations.
                          A-99
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Several types of biological monitoring programs can be
used, depending on the suspected problem and the needed
information.  Three examples that might be used are
listed below.

a.   Short-term Survey:  Site examinations made once or
     only a few times to determine quickly the bio-
     logical quality of the area and the possible
     causes for the condition.

b.   Long-term monitoring:  Sampling is conducted at
     regular intervals over a period of time.  This
     method offers the opportunity to measure seasonal
     variations and fluctuations caused by random
     events.

c.   Specific Parameter Monitoring:  Selected organisms
     or groups (such as plankton, fish or inverte-
     brates) are monitored for changes in numbers,
     size, condition, etc., and extrapolations are made
     about water quality.

If transient pollution problems following a storm are
suspected, the following biological sampling may yield
valuable information on the extent and severity of the
problem:

     Conduct three surveys, one during a dry period, a
     second directly after a period of heavy rainfall,
     and the third approximately a month after a heavy
     rainfall.  The first set of samples provide base-
     line information on the quality of the stream or
     lake.  The second set will indicate the immediate
     effects of scouring and runoff materials.  The
     third set will provide information on the extent
     of recovery following storm conditions and whether
     the effects are long-term.  For each survey, a
     comparable area relatively unaffected by runoff
     would also have to be sampled to provide a control,

Ideally, permanent biological collections are made and
identification to species level are established where
possible.  Constraints of time and money often make
this level of study impossible.  Although modifications
of this program are possible, it must be emphasized
that the information obtained will also be reduced
accordingly.
                     A-100
-------
More superficial surveys can be conducted that provide
an overview of the condition of the system.  A general
idea of biological quality can be gained by an experi-
enced biologist making on-site field observations.  The
latter, in spite of limitations, would probably provide
sufficient information for determining whether there
was an existing nonpoint source pollution problem.  A
major disadvantage of a superficial survey is the lack
of a permanent or quantitative record for future com-
parison.

Comparable lakes or streams unaffected by point or non-
point sources should be studied for purposes of com-
parison.  In actuality, these conditions are difficult
to find.  Frequently, reaches of the stream or parts of
the lake under study can be found which are not in-
fluenced by pollution; they can be used as comparative
controls.  It must be emphasized that similarity be-
tween habitats is essential in making any comparisons
between different areas.
                     A-101
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                      ADDENDUM 1
The regression analyses relating chemical concentrations to
precipitation variables utilized the following functional
form:
                  b-L  b~       b
          Y = bX   X   -  •  -X  n
     or, ln(Y +1) = In bo + b^lnX.^ + .  . .  + b  (In XR)


     where:    Y is a chemical concentration;

               X-,,. .  . ,Xn are precipitation variables; and

               bo, bj,. .  ., bn are coefficients to be

               estimated.


The objective was to control for effects of basin charac-
teristics on Y by allowing the "constant term"  (In b )
to assume different values for different basins.  This was
done by inserting dummy variables into the logarithmic form
of the regression.  Each was simply a variable with a value
of unity for all observations pertaining to a given basin,
and zero for all other observations.  There was thus one
dummy variable corresponding to each basin.  These could be
entered into the regression as ordinary independent vari-
ables; the regression coefficient obtained for each would
be, in effect, an estimate of  (In bQ) for the given basin.

A minor complication was that the full set of dummy vari-
ables could not be entered along with a conventional con-
stant term since these would be redundant  (resulting in
singularity of the covariance matrix).  For convenience, the
ordinary constant term was retained, and the first dummy
variable was deleted.  The regression equation was therefore
the following:
                        A-1Q2
-------
     In(Y + 1) = Inb0 + a2D2 + '  '  'amDm


                 + b^lnX-^ + . .  . + bn(lnXn)


          where:  D_ , .  .   . , Dm are dummy variables; and

                  a~ / .  .   ./ am are additional parameters

                  to be estimated.


The appropriate constant term for a given basin could then
be obtained as the sum of  In b ,  as estimated in the regres-
sion, and the regression coefficient for the dummy variable
pertaining to that basin.   The predictive equation for
basin "i" was thus the following:
Y = -
              (b0 exp(ai))
                                     bn
In all regressions cited here, the set of dummy variables
as a whole made a statistically significant contribution
(at the 1% level) to the explanation of the dependent
variable.  The regression coefficients and significance
tests for individual dummy variables are not of major in-
terest and therefore are not reproduced here.
                         A-103
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                     BIBLIOGRAPHY
Abt Associates, Inc.  "Preventive Approaches to Urban Storm-
     water Management" (Report forthcoming).  Prepared for
     U.S. Environmental Protection Agency by Abt Associates,
     Cambridge, Massachusetts, 1976.

Ahl, T.  "Effects of Man-induced and Natural Loading of
     Phosphorus and Nitrogen on the Large Swedish Lakes."
     Verhandlungen Internationale Vereinigung fuer Theo-
     retische und Angewandte Limnologie, 19:1125-1132, 1975.

American Public Works Association.  "National Characteriza-
     tion, Impacts and Critical Evaluation of Stormwater
     Discharges, Nonsewered Urban Runoff and Combined Sewer
     Outflows,  (Final Report Draft)."  Prepared for the U.S.
     EPA, Washington, D.C., August 1975.

American Public Works Association.  "Water Pollution Aspects
     of Urban Runoff."  Prepared for Federal Water Quality
     Control Administration, 1969.

Amy, G., et al.  "Water Quality Management Planning for
     Urban Runoff."  Prepared for U.S. Environmental Pro-
     tection Agency by URS Research Company, EPA 440/9-75-
     004, NTIS PB 241 689, 1974.

Anderson, D. G.  "Effects of Urban Development on Floods in
     Northern Virginia."  U.S. Geological Survey Open File
     Report, 1968.

Andersen, D. R.  "Water Quality Models for Urban and
     Suburban Areas."  Nebraska Water Resources Research
     Institute, University of Nebraska, Lincoln, Nebraska,
     1974.

"Applications of Stormwater Management Models."  Handout
     at EPA seminar at University of Massachusetts, Amherst,
     July 28-August 1, 1975.

Aron, G., et al.  "A Method for Integrating Surface and
     Ground Water Use in Humid Regions."  Pennsylvania State
     University, Institute for Research on Land and Water
     Resources, Research Publication No. 76, University
     Park, Pennsylvania, 1975.
                          A-104
-------
AVCO Economic Systems, Inc.  "Storm Water Pollution from
     Urban Land Activity."  Prepared for U.S. Department of
     the Interior by AVCO Economic Systems, Inc., Washing-
     ton, D.C., 1970.

Bansal, M. K.  "Deoxygenation in Natural Streams."  Water
     Resource Bulletin, Vol. 11, No. 3, pp. 491-501, 1975.

Battelle Columbus Labs.  "Development of the Arizona
     Environmental and Economic Trade-off Model."  Prepared
     for the state of Arizona Department of Economic Plan-
     ning and Development, Columbus, Ohio, March 31, 1973.

Beck, Alan M.  "The Ecology of Stray Dogs, a Study of Free
     Ranging Urban Animals."  York Press, Baltimore, Mary-
     land, 1973.

Benjes, H. H., et al.  "Storm-Water Overflows from Combined
     Sewers."  Journal of the Water Pollution Control
     Federation, Vol. 33, No. 12, pp. 1251-1259, 1961.

Benzie, W. J., and Courphaine, R. J.  "Discharges from
     Separate Storm Sewers and Combined Sewers."  Journal of
     the Water Pollution Control Federation, Vol. 38, No. 3,
     pp. 410-421, 1966.

Berger, Lewis and Associates.  "Section 303(e)  Water Quality
     Management Basin Plan, Northeast New Jersey Urban
     Area." Prepared for New Jersey Department of Environ-
     mental Protection, 1975.

Betson, R. P., and McMaster, W.  M.  "Non-point Source
     Mineral Water Quality Model."  Journal of the Water
     Pollution Control Federation, Vol. 47, No.  10, pp.
     2461-2473, 1975.

Biesecker, James E., and Liefeste, D. K.  "Water Quality of
     Hydrologic Benchmarks:  An Indicator of Water Quality
     in the Natural Environment."  USGS Circular 460-E,
     1975.

Biggar, J. W., and Corey, R. B.   "Agricultural Drainage
     of Eutrophication."  Eutrophication; Causes, Conse-
     quences, Correctives.   National Academy of  Sciences,
     Washington,  D.C., 1969.
                         A-105
-------
Black, Crow and Eidsness, Inc.  "Storm and Combined Sewer
     Pollution Sources and Abatement."  U. S. Environmental
     Protection Agency, NTIS PB 201 725, 1971.

Blackman, W. C. , Jr., et al.  "Mineral Pollution in the
     Colorado River Basin."  Journal of the Water Pollution
     Control Federation, Vol. 45, No. 7, pp. 1517-1557,
     1973.

Blackwood, K. R.  "Runoff Water Quality of Three Tucson
     Watersheds."  U.S. Environmental Protection Agency,
     NTIS PB 240 287, 1974.

Bowman, H. R., Conway, J. G. and Asaro, F.  "Atmospheric
     Lead and Bromine Concentrations in Berkeley, Cali-
     fornia, 1963-1970."  Environmental Science and Tech-
     nology, Vol. 6, No. 6, pp. 556-560, 1972.

Branch, Melville C., City Planning and Aerial Information.
     Harvard University Press, Cambridge, Massachusetts,
     1971.

Brandes, Charles E.  "Methods of Synthesis for Ecological
     Planning."  Master's Thesis, University of Pennsyl-
     vania, Philadelphia, 1973.

Brandstetter, A.  "Comparative Analysis of Urban Stormwater
     Models."  Pacific Northwest Laboratories, Battelle
     Memorial Institute, Richland, Washington, 1974.

Brown, H. E.  "A System for Measuring Total Sediment Yield
     from Small Watersheds."  Water Resources Research, Vol
     6, pp. 818-826, 1970.

Brown, H. J., et al.  "Empirical Models of Urban Land Uses:
     Suggestions on Research Objectives and Organization."
     Columbia University Press, New York, New York, 1972.

Brown, J. C., Shaw, C. M. and Read, N. P.  "Nutrients and
     Suspended Sediments for Forested Watersheds in the
     East-Central Sierra Nevada."  University of Nevada,
     Reno, Nevada, n.d.
                         A-106
-------
Brown, J. C.,  Skau, C. M. and Howe, W. R.  "Nutrient and
     Sediment Production from Forested Watersheds."  Paper
     No. 73-201, Presented at the Annual Meeting of the
     American Society of Agricultural Engineers at Lexing-
     ton, Kentucky, June 17-20, 1973.

Brown, R., et al.  "Empirical Models of Urban Land Use:
     Suggestions on Research Objectives and Organization."
     Columbia University Press, New York, New York, 1972.

Brusven, M. A. and Phathen, K. V.  "Influence of Stream
     Sediments on Distribution of Macrobenthos."  Journal of
     Entomological Society of British Columbia (Canada),
     Vol. 71,  pp. 25-32, October 1974.

Bryan, E.H.  "Concentrations of Lead in Urban Storm Water."
     Journal of the Water Pollution Control Federation, Vol.
     46, No. 11, pp. 2419-2421, 1974.

Bryan, E. H.,  "Quality of Stormwater Drainage from Urban
     Land Areas in North Carolina."  Water Resources Re-
     search Institute1 of North Carolina, Raleigh, North
     Carolina, 1970.

Burm, R. J., Krawczyk, D. F. and Harlow, G. L.  "Chemical
     and Physical Comparison of Combined and Separate Sewer
     Discharges."  Journal of the Water Pollution Control
     Federation, Vol. 40, No. 1, pp. 112-126, 1968.

Burm, R. J. and Vaughan, R. D.  "Bacteriological Comparison
     Between Combined and Separate Sewer Discharges in
     Southeastern Michigan."  Journal of the Water Pollution
     Control Federation, Vol. 38, No. 3, pp.  400-409, 1966.

Cahill, T. H., Imperato, P. and Verhoff, F. H.  "Evaluation
     of Phosphorus Dynamics in a Watershed."  Journal of the
     Environmental Engineering Division, Proceedings of the
     American Society of Civil Engineers, Vol. 100, EE2, pp.
     439-458,  1974.

Cairns, J., and Dickson, K. L. , eds.  "Biological Methods
     for the Assessment of Water Quality."  American Society
     for Testing and Materials, Philadelphia, Pennsylvania,
     1973.
                         A-107
-------
Carey, G. H., et al.  "Urbanization, Water Pollution,
     and Public Policy."  Center for Urban Policy Research,
     Rutgers University, New Brunswick, New Jersey, 1972.

Catanese, A. J.  "Scientific Methods of Urban Analysis."
     University of Illinois Press, Chicago, Illinois.  1972.

Cherkauer, D. S.  "Urbanization Impact on Water Quality
     During a Flood in Small Watersheds."  Water Resources
     Bulletin, Vol. 11, No. 5, pp. 987-998, 1975.

Chen, C. N.  "Evaluation and Control of Soil Erosion in
     Urbanizing Watersheds."  Proceedings of the National
     Symposium on Urban Rainfall and Runoff and Sediment
     Control, University of Kentucky, Lexington, Kentucky,
     1974.

Chow, T. J. and Earl, J. L.  "Lead Aerosols in the Atmos-
     phere, Incremental Concentrations"  (Report).  Science,
     Vol. 169, p. 577, 1970.

Chun, M. J., Young, R. H. F. and Anderson, G. K.  "Waste-
     water Effluents and Surface Runoff Quality."  Water
     Resources Research Center, Technical Report No. 63,
     Honolulu, Hawaii, 1972.

Clark, L. J., Guide, V. and Pheiffer, T. H.  "Nutrient
     Transport and Accountability in the Lower Susquehanna
     River Basin - Summary and Conclusions."  U.S. Environ-
     mental Protection Agency, Region III, Annapolis Field
     Office Technical Report No. 60, EPA 903/9-74-014, 1974.

Cleveland, J. G., et_ al.  "Storm Water Pollution from Urban
     Land Activity."  Combined Sewer Overflow Abatement
     Technology, Water Pollution Control Research Series,
     U.S. Environmental Protection Agency, 1970.

Cleveland, J. A., Reid, G. W. and Harp, J. F.  "Evaluation
     of Dispersed Pollutional Loads from Urban Areas."  NTIS
     PB 263 746, n.d.

Colston, N. V., Jr.  "Characterization and Treatment of
     Urban Land Runoff."  Prepared for U.S. Environmental
     Protection Agency, EPA 670/2-74-096, 1974.
                         A-108
-------
Colston, N. V., Jr.  "Pollution from Urban Land Runoff."
     University of North Carolina Water Resources Research
     Institute at North Carolina State University, Durham,
     North Carolina, 1974.

Colston, Newton V., Jr. and Tafuni, Anthony N.  "Urban Land
     Runoff Considerations."  Urbanization and Water Quality
     Control, W. Whipple, Jr., ed., American Water Resources
     Association, Minneapolis, Minnesota, 1975.

Commonwealth of Pennsylvania, Department of Environmental
     Resources.  "Technical Manual for Sewage Enforcement
     Officers."  Harrisburg, Pennsylvania, 1974.

Corey, G. H., et al.  "Urbanization, Water Pollution, and
     Public Policy."  Center for Urban Policy Research,
     Rutgers University, New Brunswick, New Jersey, 1972.

Coughlin/ Robert E., Berry, David and Hammer, Thomas R.
     "Environmental Study of the Poquessing Watershed."
     Regional Science Research Institute, Philadelphia,
     Pennsylvania,  1976.

Coughlin, R. E. and Hammer, T. R.  "Environmental Study of
     the Wissahickon Watershed within the City of Phila-
     delphia."  Regional Science Research Institute, Phila-
     delphia, Pennsylvania, 1973.

Coughlin, Robert E. and Hammer, Thomas R.  "Stream Quality
     Preservation Through Urban Development."  Prepared for
     U.S. Environmental Protection Agency by the Regional
     Science Research Institute, Philadelphia, Pennsylvania,
     EPA-R5-73-019, 1973.

Cowan, W. F. and Lee, G. F.  "Leaves as a Source of Phos-
     phorus."  Environmental Science and Technology, Vol. 7,
     No. 9, p. 853, 1973.

Crecelius, E. A. and Piper, D. Z.  "Particulate Lead Con-
     tamination Recorded in Sedimentary Cores from Lake
     Washington, Seattle."  Environmental Science -and Tech-
     nology, Vol. 7, pp. 1053-1067, 1973.

Crim, R. L. and Lovelace, N. L.  "Auto-Qual Modeling Sys-
     tem."  U.S. Environmental Protection Agency, Region
     III, Annapolis Field Office Technical Report #54, 1973.
                         A-109
-------
Daines, R. H., Motto, H., and Chitko, D. M.  "Atmospheric
     Lead:  Its Relationship to Traffic Volume and Proximity
     to Highways."  Environmental Science and Technology,
     Vol. 4, p. 318, 1970.

de Gueare, T. V. and Ongerth, J. E.  "Empirical Analysis
     of Commercial Solid Waste Generation."  Journal of the
     Sanitary Engineering Division, Proceedings of the
     American Society of Civil Engineers, Vol. 97, SA6, pp.
     843-850, 1971.

Digiano, F. A. and Coler, R. A.  "Definition of Procedures
     for Study of River Pollution by Non-point Urban Sour-
     ces."  U.S. Environmental Protection Agency, NTIS PB
     237 972, 1974.

Dillion, P. J. and Kirchner, W. B.  "The Effects of Geology
     and Land Use on the Export of Phosphorus from Water-
     sheds."  Water Research  (Great Britain), Vol. 9, pp.
     135-148, 1975.

Dow Chemical Company.  "An Economic Analysis of Erosion and
     Sediment Control Methods for Watersheds Undergoing
     Urbanization."  Prepared for the U.S. Department of the
     Interior, 1972.

Dudley, John G. and Stephenson, D. A.   "Nutrient Enrichment
     of Ground Water from Septic Tank Disposal Systems."
     Upper Great Lakes Regional Commission, 1973.

Dugan, G. L. and McGaughey, P. H.  "Enrichment of Surface
     Waters."  Journal of the Water Pollution Control
     Federation, Vol. 46, No. 10, pp. 2261-2280, 1974.

Dunbar, D. D. and Henry, J. G. F.  "Pollution Control
     Measures for Stormwaters and Combined Sewer Overflows."
     Journal of the Water Pollution Control Federation, Vol.
     38, No. 1, pp. 9-26, 1966.

Durbin, Timothy, Jr.  "Digial Simulation of the Effects of
     Urbanization on Runoff in the Upper Santa Ana Valley,
     California."  U.S. Department of the  Interior, Geo-
     logical Survey Water-Resources Investigations 41-73,
     1974.
                          A-110
-------
Ecology and the Economy...A Concept for Balancing Long
     Range Goals."  Urban and Rural Lands Committee.  Paci-
     fic Northwest River Basin Commission, November, 1973.

Edwards, D.  "Some Effects of Siltation Upon Aquatic
     Macrophyte Vegetation in Rivers."  Hydrobiologia, Vol.
     34, No. 1, pp. 29-37, 1969.

Elfers, K. and Hufachmidt, M. M.  "Open Space and Urban
     Water Management Phase 1:  Goals and Criteria."
     University of North Carolina, Water Resources Research
     Institute, Report No. 104, Chapel Hill, North Carolina,
     1975.

Elgmork, K., et al.  "Polluted Snows in Southern Norway
     During the Period 1968-1971."  Environmental Pollution,
     Vol. 4, No. 1, p. 41, 1973.

Emery,  R. M.,  Moon, C. E. and Welch, E. B.  "Enriching
     Effects of Urban Runoff on the Productivity of a
     Mesotrophic Lake."  Water Research (Great Britain),
     Vol. 7, pp. 1506-1516, 1973.

Engineering-Science, Inc.  "Comparative Costs of Erosion
     and Sediment Control Construction Activities."  Pre-
     pared for U.S. Environmental Protection Agency, EPA
     430/9-73-016, 1973.

Engman, E. T.   "Partial Area Hydrology and its Application
     to Water Resources."  Water Resources Bulletin, Vol.
     10, No. 3. pp. 512-521, 1974.

Engman, E. T.  and Ragowski, A. S.  "A Partial Area Model
     for Storm Flow Synthesis."  Water Resources Research,
     Vol. 10,  No. 3, pp. 464-472, 1974.

"Environmental Management for the Metropolitan Area -
     Part II:   Urban Drainage."  U.S. Army Corps. Seattle
     District, 1974.

"EPA Prepares Effluent Guidance for 21 Industries for
     Permit Program."  Environment Reporter, Vol. 3, No. 37,
     pp. 1053-1057, 1973.
                         A-lll
-------
Espey, W. H. Jr., and Winslow, D. E.  "Urban Flood Fre-
     quency Characteristics."  Journal of the Hydraulics
     Division, American Society of Civil Engineers, Vol.
     100, HY2, pp. 279-293, 1974.

"Eutrophication: Causes, Consequences, Correctives."
     Proceedings of a Symposium, National Academy of Sci-
     ences, Washington, D. C., 1969.

"Evaluation of the Effects of Urbanization on Aquatic
     Ecology and Hydrologic Regimes."  Hydrocomp, Inc., PB-
     247 095/3WP, Palo Alto, California, 1975.

Field, R.  "Coping with Urban Runoff in the United States."
     Water Research (Great Britain), Vol. 9, pp. 499-511,
     1975.

Field, R.  "Urban Pollution and Associated Effects of
     Street Salting."  Edison Water Quality Research Lab,
     National Environmental Research Center, Cincinnati,
     Ohio, Environmental Protection Agency, Edison, New
     jersey, 1972.

Field, R. and Knowles, D.  "Urban Runoff and Combined
     Sewer Overflow."  Journal of the Water Pollution
     Control Federation, Vol. 47, No. 6, pp. 1352-1369,
     1975.

Field, R. and Lager, J. A.  "Urban Runoff Pollution Control,
     State-of-the-Art."  Journal of the Environmental
     Engineering Division, Proceedings of the American
     Society of Civil Engineers, Vol. 101, EEl, pp. 107-125,
     1975.

Field, R. and Wiezel, P.   "Urban Runoff and Combined Sewer
     Overflow."  Journal of the Water Pollution Control
     Federation, Vol. 45, No. 6, pp. 1108-1115, 1973.

Fellos, John and Molof, Alan H.  "Effect of Benthal Deposits
     on Oxygen and Nutrient Economy of Flowing Waters."
     Journal of the Water Pollution Control Federation, Vol.
     44, No. 4, pp. 644-662, 1972.
                         A-112
-------
Fillos, John and Swanson, William R.  "The Release Rate of
     Nutrients from River and Lake Sediments."  journal of
     the Water Pollution Control Federation, Vol. 47, No. 5,
     pp. 1032-1042, 1975.

Floyd, C. F. and Rowan, M. J.  "Implications of Zoning as
     an Urban Water Management Measure."  Department of Real
     Estate, University of Georgia and Environmental Re-
     sources Center, Georgia Institute of Technology, 1976.

Foehrenbach, J.  "Eutrophication."  Journal of the Water
     Pollution Control Federation, Vol. 45, No. 6, pp. 1237-
     1244, 1973.

Franklin Institute Research Laboratories.  "Selected Urban
     Storm Water Runoff Abstracts."  U.S. Environmental
     Protection Agency, 11024 EJC, 1970.

Frey, J. C., Gamble, H. B. and Sauerlender, 0. H.  "Eco-
     nomics of Water Supply Planning and Management."
     Institute for Research on Land and Water Resources
     Publication No. 90, Penn State University, University
     Park, Pennsylvania, 1975.

Fruh, G. E.  "The Overall Picture of Eutrophication."
     Journal of the Water Pollution Control Federation, Vol.
     39, No. 9, pp. 1449-1463, 1967.

Gambell, A. W.  "Sulfate and Nitrate Content of Precipita-
     tion Over Parts of North Carolina and Virginia."  U.S.
     Geological Survey Professional Paper 475C, C209, 1963.

Gannett, Fleming, Corddry and Carpenter, Inc.  "Storm Water
     Management Alternatives."  From final report on Watts
     Branch Storm Water Management Study to Montgomery
     County, Maryland Department of Environmental Planning,
     1975.

Gaufin, A. R.  "Water Quality Requirements of Aquatic
     Insects."  U.S. Environmental Protection Agency, EPA
     660/3-74-004, 1973.

Gburek, W. J. and Brogan, J. G.  "A Natural Non-Point
     Phosphate Input to Small Streams."  Northeast Watershed
     Research Center, University Park, Pennsylvania, n.d.
                         A-113
-------
Gizzard, T. J. and Jennelle, E. M.  "Will Wastewater
     Treatment Stop Eutrophication of Impoundments?"
     Presented at the 27th Purdue Industrial Waste Con-
     ference, West Lafayette, Indiana, 1972.

Graham, F. H., Costello, L. S. and Mallon, H. J.  "Estima-
     tion of Imperviousness and Specific Curb Length for
     Forecasting Stormwater Quality and Quantity."  Journal
     of the Water Pollution Control Federation, Vol. 46, No.
     4, pp. 717-725, 1974.

Grossman, D., Hudson, J. F. and Marks, D. H.  "Waste
     Generation Models for Solid Waste Collection."  Journal
     of the Environmental Engineering Division, Proceedings
     of the American Society of Civil Engineers, Vol. 100,
     EE6, pp. 1219-1230, 1974.

Grava, Sigurd.  Urban Planning Aspects of Water Pollution
     Control.  Columbia University Press, New York, New
     York, 1969.

Guy, H. P.  "Research Needs Regarding Sediment and Urbani-
     zation. "  Journal of the Hydraulics Division, Proceed-
     ings of the American Society of Civil Engineers, Vol.
     93, HY6, pp. 247-254, 1967.

Guy, H. P.  "Residential Construction and Sedimentation at
     Kensington, Maryland."  Federal Inter-Agency Sedimenta-
     tion Conference, AR5 Miscellaneous Publication 970,
     1965.

Guy, H. P. and Ferguson, G. E.  "Sediment in Small Reser-
     voirs Due to Urbanization."  Journal of the Hydraulics
     Division, Proceedings of the American Society of Civil
     Engineers, Vol. 88, No. HY2, pp. 27-37, March 2962.

Hagarman, James.  Personal Conversation in Philadelphia,
     Pennsylvania, April 29, 1976.

Haith, D. A.  "Land Use and Water Quality in New York
     Rivers."  Journal of the Environmental Engineering
     Division, Proceedings of the American Society of Civil
     Engineers, Vol. 102, EEl, pp. 1-15,  1976.
                         A-114
-------
Hammer, Thomas R.  "Stream Channel Enlargement due to
     Urbanization."  Water Resources Research, Vol. 9, No.
     6, 1973.

Hammer, T. R.  "Effects of Urbanization on Stream Channels
     and Stream Flow."  Regional Science Research Institute,
     Philadelphia, Pennsylvania, 1973a.

Hammer, T. R.  "Water Quality Determination in a Suburban!z-
     ing Basin:  Brandywine Creek, Pennsylvania."  Regional
     Science Research Institute Discussion Paper No. 78,
     Philadelphia, 1974.

Hanes, R. E., Zelazny, L. W., and Blaser, R. E.  "Effects
     of De-icing Salts on Roadside Plants and Water Sup-
     plies."  Department of Agronomy, Virginia Polytechnic
     Institute, Blackburg, Virginia, 1967.

Harbridge House.  "Key Land Use Issues Facing EPA."  Pre-
     pared for U.S. Environmental Protection Agency, NTIS
     PB, pp. 235-345, 1974.

Harkin, John M., Jawson, M. D., and Baker, F. G.  "Cause
     and Remedy of Failure of Septic Tank Seepage Systems."
     Proceedings, Second National Conference on Individual
     Onsite Wastewater Systems, National Sanitation Founda-
     tion, Ann Arbor, Michigan, pp. 119-124, 1976.

Harms, L. L, and Southerland, E. V.  "A Case Study in Non-
     Point Source Pollution in Virginia."  Virginia Water
     Resources Research Center Bulletin No. 88, Virginia
     Polytechnic Institute, Blacksburg, Virginia, 1975.

Hartt, J. P.  "A Study of Pollution Loadings from Urban
     Runoff."  Water Pollution Research in Canada, Vol. 8,
     pp. 16-25, 1973.

Hawkes, H. A.  "Water Quality:  Biological Considerations."
     Chemistry and Industry, pp. 990-1000, December 21,
     1974.

Hawkins, R. H. and Judd, J. H.  "Water Pollution as Affected
     by Street Salting."  Water Resources Bulletin, Vol. 8,
     No. 6, pp. 1246-1252, 1972.
                         A-115
-------
Heaney, J. P. and Sullivan, R. H.  "Source Control of
     Urban Water Pollution."  Journal Water Pollution
     Control Federation, Vol. 43, No. 4, pp. 571-579, 1971.

Heaney, J. P., et al.  "Urban Stormwater Management Model-
     ing and DecTs ion-Making."  Prepared for U.S. Environ-
     mental Protection Agency, National Environmental
     Research Center, NTIS PB 242 290, 1975.

Keeps, D. P. and Mein, R. G.  "Independent Comparison of
     3 Urban Runoff Models."  Journal of the Hydraulics
     Division, Proceedings of the American Society of Civil
     Engineers, Vol. 100, HY7, pp. 995-1009, 1974.

Heerdegen, R. G. and Reich, B. M.  "Unit Hydrographs for
     Catchments of Different Sizes and Dissimilar Regions."
     Institute for Research on Land and Water Resources,
     Reprint Series No. 44, Pennsylvania State University,
     University Park, Pennsylvania, 1974.

Helly, Walter.  Urban Systems Models.  Academic Press,
     New York, New York, 1975.

Henningson, Durham and Richardson, Inc.  "Combined Sewer
     Overflow Abatement Plan."  Draft Report for the U.S.
     Environmental Protection Agency, 11024 FEG, Des Moines,
     Iowa, 1973.

Hergert, S. L.  "Urban Runoff Quality and Modeling Study."
     Prepared for U.S. Environmental Protection Agency, NTIS
     PB, 237 141, 1972.

Hiemstra, L. A. V.  "Joint Probabilities in the Rainfall-
     Runoff Relation."  Institute for Research on Land and
     Water Resources, Reprint Series No. 14, Pennsylvania
     State University, University Park, Pennsylvania, 1969.

Hill, D. E. and Thomas, H. F.  "Use of Natural Resources
     Data in Land and Water Planning."  The Connecticut
     Agricultural Experiment Station, Bulletin 733, New
     Haven, Connecticut, 1972.

Hoak, R. D.  "Physical and Chemical Behavior of Suspended
     Solids."  Sewage and Industrial Wastes, Vol. 31, No.
     12, pp. 1401-1408, 1959.
                         A-116
-------
Hobble, J. E. and Likens, G. E.  "The Output of Phosphorus
     Dissolved Organic Carbon, and Fine Particulate Carbon
     from Hubbard Brook Watershed."  Limnology and Ocean-
     ography, Vol. 18, No. 5, pp. 734-742, 1973.

Halsworth, E. G. and Adams, W. A.  "The Heavy Metals,Content
     of Rainfall in the East Midlands."  Environmental
     Pollution  (Great Britain), Vol. 4, p. 231, 1973.

Holzer, Thomas L.  "Limits to Growth and Septic Tanks."
     Paper Presented at Conference on Rural Environmental
     Engineering, Warren, Vermont, 1973.

Horbeck, J. W.  "Storm Flow from Hardwood-Forested and
     Cleared Watersheds in New Hampshire."  Water Resources
     Research, Vol. 9, No. 2, 1973.

Horton, J. P.  "Street Cleaning Effectiveness: Vacuum
     Sweepers."  The APWA Reporter, pp. 20-22, April 1976.

Hossain, A., Delleur, J. W. and Rao, R. A.  "Evaporation
     Infiltration and Rainfall-Runoff Processes in Urban
     Watersheds."  Water Resources Research Center, Tech-
     nical Report No. 41, Purdue University, West Lafayette,
     Indiana, 1974.

Howard, W. T. and Hammer, T. R.  "Water Quality Impacts of
     Unsewered Housing."  Regional Science Research Insti-
     tute Discussion Paper No. 66, Philadelphia, Pennsyl-
     vania, 1973.

Howells, D. H.  "Water Quality Dimensions of Water Resources
     Planning."  Journal of the Hydraulics Division, Pro-
     ceedings of the American Society of Civil Engineers,
     Vol. 101, HY2, pp. 277-284, 1975.

Huber, Wayne C., et al.  "Storm Water Management Model
     User's Manual - Version II."  Prepared for U.S. Environ-
     mental Protection Agency, 1975.

Huff, D. D., et al.  "Simulation of Urban Runoff Nutrient
     Loading, and Biotic Response of a Shallow Eutrophic
     Lake."  Institute for Environmental Studies, University
     of Wisconsin, Madison, Wisconsin, 1974.
                         A-117
-------
Hwang, C. P., Huang, P. M. and Lackie, T. H.  "Phosphorus
     Distribution in Blackstrip Lake Sediments."  Journal of
     the Water Pollution Control Federation, Vol. 47, No. 5,
     pp. 1081-1085, 1975.

Hydrologic Engineering Center, U.S. Army Corps of Engineers.
     Urban Storm Water Runoff Model Storm Computer Program
     Users Guide, 1975.

Hydrologic Engineering Center, U.S. Army Corps of Engineers.
     "FY 1972 Annual Report on the Quality of Urban Storm
     Runoff Entering the San Francisco Bay."  1972.

Hydroscience in U.S. EPA.  Areawide Assessment Procedures
     Manual, report forthcoming.

Hynes, H. B. N.  The Ecology of Running Waters.  University
     of Toronto Press, Toronto, Ontario, 1970.

International Business Machines, Inc.  "IBM Scientific
     Computing Symposium, Land and Air Resource Management."
     White Plains, New York, 1968.

Interstate Sanitation Commission.  "Combined Sewer Overflow
     Study for the Hudson River Conference."  New York, New
     York, 1972.

Jaworski, N. A. and Hetling, L. J.  "Relative Contributions
     of Nutrients to the Potomac River Basin from Various
     Sources."  U.S. Department of the Interior, Federal
     Water Pollution Control Administration, Chesapeake
     Technical Support Laboratory, Technical Report No. 31,
     1970.

Johnson, R. E., Rossano, A. T. Jr. and Sylvester, R. 0.
     "Dustfall as a Source of Water Quality Impairment."
     Journal of the Sanitary Engineering Division, Pro-
     ceedings of the American Society of Civil Engineers,
     Vol. 92, SA1, pp. 245-268, 1966.

Jordan, R. A. and Bender, M. E.   "An in situ Evaluation of
     Nutrient Effects in Lakes."  Prepared  for U.S. Environ-
     mental Protection Agency by Virginia Institute of
     Marine Science, Gloucester Point, Virginia, EPA-R3-73-
     018, 1973.

Judd, J. H.  "Lake Stratification Caused by Runoff from
     Street De-icing."  Water Research  (Great Britain), Vol.
      4, pp.  521-532,  1970.
                         A-118
-------
Judd, John A.  "Effect of Salts from Street Runoff on
     Benthic Organisms."  University of Wisconsin, Great
     Lakes Center, Milwaukee, Wisconsin, 1967.

Kaufman, W. J.  "Chemical Pollution of Ground Waters."
     Journal of the American Water Works, Vol. 66, pp. 152-
     159, 1974.

Kerr, R. L., et al.  "Analysis of Rainfall - Duration -
     Frequency for Pennsylvania."  Institute for Research on
     Land and Water Resources Research, Publication No. 70,
     Penn State University, University Park, Pennsylvania,
     1970.

Keup, L. E.  "Biology of Water Pollution."  W. M. Ingram and
     K. M. Mackenthum, Eds., U.S. Department of the In-
     terior, Federal Water Pollution Control Administration,
     1967.

Khanna, S. D.  "Effects of Highways on Surface and Sub-
     surface Waters."  Public Works, Vol. 104, pp. 1171-
     1182, 1973.

King, D. L. and Ball, R. C.  "Comparative Energetics of a
     Polluted Stream."  Limnology and Oceanography, Vol. 12,
     No. 1, pp. 27-33, 1967.

Klein, L. A., £t al_.  "Source of Metals in New York City
     Wastewater."  Journal of Water Pollution Control
     Federation, Vol. 46, p. 2653, 1974.

Kluesener, J. W. and Lee, G. F.  "Nutrient Loading from a
     Separate Storm Sewer in Madison, Wisconsin."  Journal
     of the Water Pollution Control Federation, Vol. 46, pp.
     920-936, 1974.

Knauer, D. R.  "The Effect of Urban Runoff on Phytophankton
     Ecology."  Verhandlungen, Internationale Vereinigung
     fuer Theoretische und Angewandte Limnologie.  Vol. 19,
     pp. 893-903, 1975.

Kothand Araman V.  "Water Quality Characteristics of Storm
     Sewer Discharges and Combined Sewer Overflows."
     Illinois State Water Survey, Illinois Department of
     Registration and Education, Circular 109, Urbana,
     Illinois, 1972.
                         A-119
-------
Kramer, J. R.,  Herbes, S. E. and Allen, H. E.  "Phosphorus:
     An Analysis of Water, Biomass, and Sediment."  Nutri-
     ents in Natural Waters, Wiley-Interscience, New York,
     New York,  1972.

Kreisal, James F.  "Rural Wastewater Research."  Proceed-
     ings, Second National Conference on Individual On-site
     Wastewater Systems, National Sanitation Foundation, Ann
     Arbor, Michigan, pp. 145-157, 1976.

Krenkel, P. A., Cawley, W. A. and Minch, V. A.  "The
     Effect of Impounding Reservoirs on River Waste Assimi-
     lative Capacity."  Journal of the Water Pollution
     Control Federation, Vol. 37, pp. 1203-1217, 1965.

Kuhner, J. and Shapiro, M.  "Discussion of 'Urban Runoff
     Pollution Control - State-of-the-Art1, by R. Field and
     J. A. Lager."  Journal of the Environmental Engineering
     Division,  Proceeding of the American Society of Civil
     Engineers, Vol. 102, EEI, pp. 220-223, 1976.

Kuo, Chin Y.  "Evaluation of Sediment Yield Due to Housing
     Construction:  A Case Study."  Department of Civil
     Engineering, Old Dominion University, Norfolk, Vir-
     ginia.

Lager, J. A. and Smith, W. G.  "Urban Stormwater Management
     and Technology:  An Assessment."  U.S. Environmental
     Protection Agency, National Environmental Research
     Center, EPA 670/2-74-040, 1974.

Lamonds, A. G.   "Chemical and Biological Quality of Lake
     Dicie at Eustis, Flordia, with Emphasis on the Effects
     of Storm Runoff."  U.S. Geological Survey, NTIS PB 239
     014, Tallahassee, Florida, 1974.

La Valle, P. D.  "Domestic Sources of Stream Phosphates in
     Urban Streams."  Water Research  (Great Britain), Vol.
     9, pp. 915-927, 1975.

Lazrus, A. L.,  Lorange, F. and Lodge, J. R. Jr.  "Lead and
     other Metal ions in United States Precipitation."
     Environmental Science and Technology, Vol. 4, p. 55,
     1970.
                         A-120
-------
Leclerc, G.  "Methodology for Assessing the Potential Impact
     of Urban Development on Urban Runoff and the Relative
     Efficiency of Runoff Control Alternatives."  PhD The-
     sis, Massachusetts Institute of Technology, 1973.

Lee, G. F.  "Role of Phosphorus in Eutrophication and
     Diffuse Source Control."  Water Research (Great Brit-
     ain), Vol. 7, pp. 111-128, 1973.

Leopold, L. B., Wolman, M. G. and Miller, J. P.   "Fluvial
     Processes in Geomorphology."  W. H. Freeman and Com-
     pany, San Francisco, California, 1964.

Leopold, L. B.  "Hydrology for Urban Land Planning - A
     Guidebook on the Hydrologic Effects of Urban Land Use."
     U.S. Geological Survey Circular 554, 1968.

Likens, G. E., ed.  "Nutrients and Eutrophication:  The
     Limiting Nutrient Controversy."  Special Symposia (Vol.
     1), American Society of Limnology and Oceanography,
     Allen Press, Lawrence, Kansas, 1972.

Likens, G. E.  "The Runoff of Water and Nutrients from
     Watersheds Tributary to Cayuga Lake, New York."
     Cornell University Water Resources and Marine Sciences
     Center, Technical Report No. 81, Ithaca, New York,
     1974.

Likens, G. E.  "The Chemistry of Precipitation in the
     Central Finger Lakes Region."  Cornell University Water
     Resources and Marine Sciences Center, Technical Report
     No. 50, Ithaca, New York, 1972.

Loehr, R. C.  "Characteristics and Comparative Magnitude
     of Nonpoint Sources."  Journal of the Water Pollution
     Control Federation, Vol. 46, No. 8, pp. 1849-1872,
     1974.

Mallory, C. W.  "The Beneficial Use of Storm Water."  U.S.
     Environmental Protection Agency, EPA-R2-73-139, 1973.

Man-Made Lakes:  Their Problems and Environmental Effects.
     W. C. Ackermann, G. F. White and E. B. Worthington,
     eds., American Geophysical Union, Washington, D. C.,
     1973.
                         A-121
-------
Mansue, L. J. and Commings, A. B.  "Sediment Transport by
     Streams Draining into the Delaware Estuary."  Water-
     Supply Paper 1532-H, U.S. Government Printing Office,
     Washington, D.C., 1974.

Mantri, V. and Kaushik, K.  "A Model of Time-Varying,
     Non-Uniform Flow in Open Channels."  Part II, 1975.

Manuel, A. D., Gustafson, R. H. and Welch, R. B.  "Three
     Land Research Studies."  National Commission on Urban
     Problems, Report No. 12, 1968.

Marsalek, J., et al.  "Comparative Evaluation of Three
     Urban Runoff Models."  Water Resources Bulletin, Vol.
     11, No. 2, pp. 306-328, 1975.

Martin, D. M. and Gaff, D. R.  "The Role of Nitrogen in the
     Aquatic Environment."  Academy of Natural Sciences,
     NTIS PB 213 496, Philadelphia, Pennsylvania, 1972.

Maryland Department of Water Resources, Burton C. Becker
     and Thomas R. Mills.  "Guidelines for Erosion and
     Sediment Control Planning and Implementation."  Pre-
     pared for U.S. Environmental Protection Agency, EPA R2-
     72-015, 1072.

McBean, E. A. and Loucks, D. P.   "Planning and Analysis of
     Metropolitan Water Resources System."  Cornell Uni-
     versity Water Resources and Marine Science Center,
     Technical Report No. 84, NTIS PB 235 257, Ithaca, New
     York, 1974.

McCuen, R. H.  "Flood Runoff from Urban Areas."  Water
     Resources Research Center, Technical Report No. 33,
     University of Maryland, College Park, Maryland, 1975.

McElroy, A.  D., et al.  "Interim  Report on Loading Functions
     for Assessment of Water Pollution from Nonpoint Sour-
     ces."   Prepared for U.S. Environmental Protection
     Agency  by Midwest Research Institute, Kansas City,
     Missouri, 1975.

McElroy, A.  D., Chiu, S. Y. and Aleti, A.  "Analysis of
     Nonpoint  Source Pollutants in the Missouri Basin
     Region."  U.S. Environmental Protection Agency, EPA
     600/5-75-004, 1975.
                         A-122
-------
McElroy, A. D., et al.  "Water Pollution from Non-Point
     Sources."  Water Research (Great Britain), Vol. 9, pp.
     675-681, 1975.

McHarg, Ian L.  "Design with Nature."  Doubleday/Natural
     History Press, Garden City,  New York, 1969.

McPherson, M. B., Orlob, G. T., Kibler, D. F. and Chen,
     C. W.  "Management of Urban Storm Runoff."  NTIS PB 234
     316, May 1974.

Meta Systems, Inc.  "Land Use Environmental Quality Rela-
     tionship."  Prepared for U.S. Environmental Protection
     Agency under contract 68-01-2622, 1975.

Metcalf and Eddy, Inc., University of Florida and Water
     Resources Engineers.  "Storm Water Management Model."
     (4 volumes).  Prepared for U.S. Environmental Protec-
     tion Agency, 11024DOC, 1971.

Metcalf and Eddy, Inc.  "Storm Water Problems and Control
     in Sanitary Sewers."  Prepared for the U.S. Environ-
     mental Protection Agency, 11024 EQG, 1971.

Metcalf and Eddy, Inc.  "Wastewater Engineering - Collection
     - Treatment - Disposal."  McGraw-Hill Inc., New York,
     New York, 1972.

Middlebrooks, E. J.  "Modeling the Eutrophication Process."
     D. H. Falkenborg and T. E. Moloney, eds., Ann Arbor
     Science Publishers, Inc., Ann Arbor, Michigan, 1974.

Miller, Fred P. and Wolf, D. C.  "Renovation of Sewage
     Effluents by the Soil."  Proceedings of the Second
     National Conference on Individual Wastewater Systems,
     National Sanitation Foundation, Ann Arbor, Michigan,
     pp. 87-101, 1976.

Miller, John C.  "Nitrate Contamination of the Water-Table
     Aquifer by Septic Tank Systems in the Coastal Plain of
     Delaware."  Water Pollution Control in Low Density
     Areas, University Press of New England, Hanover, New
     Hampshire, pp. 121-133, 1975.
                         A-123
-------
Miller, R. Adam, Troxell, J. and Lopold, L. B.  "Hydrology
     of Two Small River Basins in Pennsylvania before
     Urbanization."  U.S. Geological Survey Professional
     Paper 701-A, 1971.

Miller, W. L. and Erickson, S. P.  "Systematic Development
     of Methodogies in Planning Urban Water Resources for
     Medium Size Communities."  Purdue University Water
     Resources Research Center, Report No. 39, West Lafay-
     ette, Indiana, 1973.

Mills, D. M. and Watson, P. S.  "Regional Environmental
     Assessment Procedure."  University of Pennsylvania,
     Philadelphia, Pennsylvania, 1974.

Minneapolis-St. Paul Sanitary District.  "Dispatching
     System for Control of Combined Sewer Losses."  Prepared
     for the U.S. Environmental Protection Agency, 11020
     FAQ, 1971.

"Models for Managing Regional Water Quality."  R. Dorfman,
     H. Jacoby and H. A. Thomas, eds.  Harvard University
     Press, Cambridge, Massachusetts, 1972.

Moore, Charles A. and Silver, Marshall L.  "Nutrient Trans-
     port by SedimentWater Interaction."  Water Resources
     Center Research Report, Illinois University, Urbana,
     Illinois, 1973.

Morrow, N. L. and Brief, R. S.  "Elemental Composition of
     Suspended Matter in Metropolitan New York."  Environ-
     mental Science and Technology, Vol. 5, No. 9, 1971.

Murray, T., et al.  "Honey Hill:  A Systems Approach for
     Planning Multiple Use of Controlled Water Areas."
     Department of Los Angeles Research Office, Harvard
     University, Cambridge, Massachusetts, 1971.

"National Conference on Managing the Environment."  Spon-
     sored by the U.S. Environmental Protection Agency,
     1973.

National Water Monitoring Panel.  "Model State Water Moni-
     toring Program."  Environmental Protection Agency, EPA
     440/9-74-002, 1975.
                         A-124
-------
Newton, C. D., et al.  "Street Runoff as a Source of Lead
     Pollution."  Journal of the Water Pollution Control
     Federation, Vol. 46, No. 5, pp. 9991000, 1974.

"Non-Point Sources of Water Pollution."  Proceedings of a
     Southeastern Regional Conference at Virginia Poly-
     technic Institute, Virginia Water Resources Research
     Center, Blacksburg, Virginia, 1975.

Norton, J. L.  "The Identification and Measurement of
     Chlorinated Hydrocarbon Pesticides Accumulated from
     Urban Runoff."  Prepared for U.S. Environmental Pro-
     tection Agency by the Oklahoma Water Resources Research
     Institute, NTIS PB 226 307, 1973.

Norvell, W. A. and Frink, C. R.  "Water Chemistry and
     Fertility of TwentyThree Connecticut Lakes."  Con-
     necticut Agricultural Experiment Station, New Haven,
     Connecticut, 1975.

"NOX Emissions from Stationary Combustion Sources."
     Journal of Environmental Engineering and Design, p.
     641, June 1974.

"Nutrients in Natural Waters."  H. E. Allen and J. R.
     Kramer, eds.  John Wiley and Sons, New York, New York,
     1972.

Ogumrombi, Joseph A. and Dobins, William E.  "The Effects
     of Benthal Deposits on the Oxygen Resources of Natural
     Streams."  Journal of the Water Pollution Control
     Federation, Vol. 42, No. 4, pp. 538-552, 1970.

Ohio-Kentucky-Indiana Regional Council of Governments.  "A
     Method for Assessing Rural Non-Point Sources and its
     Application in Water Quality Management."  Cincinnati,
     Ohio, 1975.

Oliver, B. G., Milne, J. B. and La Barne, N.  "Chloride
     and Lead in Urban Snow."  Journal of the Water Pollu-
     tion Control Federation, Vol. 46, No. 4, pp. 766-771,
     1974.

"Organisms and Biological Communities as Indicators of
     Environmental Quality - A Symposium."  Sponsored by
     Ohio Biological Survey, Ohio Environmental Protection
     Agency and U.S. Environmental Protection Agency at Ohio
     State University, 1974.
                         A-125
-------
O1Shaughnessy, J. C. and McDonnell, A. J.  "Criteria for
     Estimating Limiting Nutrients in Natural Streams."
     Pennsylvania State University Institute for Research on
     Land and Water Resources Research, Publication No. 75,
     University Park, Pennsylvania, 1973.

Palmer, C. L.  "Feasibility of Combined Sewer System."
     Journal of the Water Pollution Control Federation, Vol.
     35, No. 2, pp. 162-167, 1963.

Palmer, C. M.  "A Composite Rating of Algae Tolerating
     Organic Pollution."  Journal of Phycology, Vol. 5, No.
     1, pp. 78-82, 1969.

Palmer, C. L.  "The Pollutional Effects of Storm-Water
     Overflows from Combined Sewers."  Sewage and Industrial
     Wastes, Vol. 22, No. 2, pp. 154-165, 1950.

Papadakis, C. N. and Preul, H. C.  "Testing of Methods for
     Determination of Urban Runoff."  Journal of the Hy-
     draulics Division, Proceedings of the American Society
     of Civil Engineers, Vol. 99, HY9, pp. 1319-1335, 1973.

Papadakis, C. N. and Preul, H. C.  "Urban Runoff Model."
     Journal of the Hydraulics Division, Proceedings of the
     American Society of Civil Engineers, Vol. 98, HY10, pp.
     1789-1804, 1972.

Parmele, L. H. and McGuinness, J. L.   "Comparisons of
     Measured and Estimated Daily Potential Evapo-transpira-
     tion in a Humid Region."  Journal of Hydrology  (Nether-
     lands) , Vol. 22, pp. 239-251, 1974.

Patri, T., et al.   "Early Warning System:  The Santa Cruz
     Mountains Regional Pilot Study."  Department of Land-
     scape Architecture, College of Environmental Design,
     University of  California, Berkeley, California, 1970.

Patrick, Ruth.   "A  Proposed Biological Measure of Stream
     Conditions  Based on a Survey of  the Conestoga Basin,
     Lancaster County, Pennsylvania."  Proceedings of the
     Academy of  Natural Sciences of Philadelphia, Vol. 101,
     Philadelphia,  Pennsylvania, December 17, 1949.

Pheiffer, T. H.  and Lovelace, N. L.   "Application of Auto-
     Qual Modeling  System to the Patuxent River Basin."
     U.S. Environmental Protection Agency, Annapolis Field
     Office  Technical Report No. 58,  EPA-903/9-74-013, 1973.
                         A-126
-------
Pitt, R. E. and Amy, G.  "Toxic Materials of Street Surface
     Contaminants."  NTIS PB 224-677, August 1973.

Pitt, R. E. and Amy, G.  "Toxic Surface Analysis of Street
     Surface Contaminants."  Prepared for the U.S. Environ-
     mental Protection Agency, 11034 FUJ, EPA R2-73-283,
     1973.

Plews,  Gary D.  "The Adequacy and Uniformity of Regulations
     for Onsite Wastewater Disposal - A State Viewpoint."
     Proceedings,  Second National Conference on Individual
     Onsite Wastewater Systems, National Sanitation Founda-
     tion, Ann Arbor, Michigan, pp. 139-144, 1976.

Plymouth Architectural and Planning Associates, Inc., and
     Betz Environmental Engineers, Inc.  "Workshop on Storm
     Water Management."  Prepared for Pennsylvania Depart-
     ment of Community Affairs, 1975.

Poertner, H. G.  "Practices in Detention of Urban Stormwater
     Runoff."  American Public Works Association, Chicago,
     Illinois, 1974.

Pollution Ecology of Freshwater Invertebrates.  C. W. Hart
     and S. L. H.  Fuller, eds.  Academic Press, Inc., New
     York, New York, 1974.

Pravoshinsky, N. A.  "Description of the Drainage of Street
     Flushing."  Soviet Hydrology, Selected Papers, Issue
     No. 2, pp. 168-170, 168, 1968.

Preul,  H. C.  "Contaminants in Ground Water near Waste
     Stabilization Ponds."  Journal of the Water Pollution
     Control Federation, Vol. 40, No. 4, pp. 659-669, 1968.

Processes, Procedures and Methods to Control Pollution
     Resulting from all Construction."  U.S. Environmental
     Protection Agency, Office of Air and Water Programs,
     EPA 430/9-73-00 7, 1973.

Putnam, A. L.  "Effects of Urban Development of Floods in
     the Piedmont Province of North Caroline."  U.S. Geo-
     logical Survey Open File Report, 1972.

Putnam, D. and Olson, T. A.  "An Investigation of Nutrients
     in Western Lake Superior."  School of Public Health,
     University of Minnesota, 1960.
                         A-127
-------
Quart, Edison L. , Young, R. H. F., Burbank, N. C. Jr. and
     Lau, L. S.  "Effects of Surface Runoff into the South-
     ern Sector of Kaneoke Bay."  Water Resources Research
     Center, University of Hawaii, January 1970.

Radziul, J. V., Cairo, P. R. and Sraoot, G. S.  "Does
     Stormwater Damage?"  Water Pollution Control Associa-
     tion of Pennsylvania Magazine, pp. 26-36, September-
     October 1975.

Radziul, J. V., Cairo, P. R. and Smoot, G. S.  "Does Storm-
     water Pollute?"  Water Pollution Control Association of
     Pennsylvania, 45th Annual Conference, Penn State Uni-
     versity, University Park, Pennsylvania, August 1973.

Ragan, R. M. and Dietemann, A. J.  "Impact of Urban Storm-
     water Runoff on Stream Quality."  Urbanization and
     Water Quality Control, American Water Resources Associ-
     ation, Minneapolis, Minnesota, 1975.

Randall, Clifford W., et al.  "Characterization of Urban
     Runoff in the Oceogran Watershed of Virginia."  Urbani-
     zation and Water Quality Control, American Water Re-
     sources Association, Minneapolis, Minnesota, 1975.

Rao, R. A. and Chenchagya, B. T.  "Probabilistic Analysis
     and Simulation of the Short Time Increment Rainfall
     Process."  Purdue University Water Resources Research
     Center, Technical Report No. 55, West Lafayette,
     Indiana, 1974.

Rao, R. A. and Rao, R. G. S.  "Analysis of the Effect of
     Urbanization on Rainfall Characteristics - I."  Purdue
     University Water Resources Research Center, Technical
     Report No. 50, West Lafayette, Indiana, 1974.

Rao, R. A. and Rao, R. G. S.  "Comparative Analysis of
     Estimation Method in Non-Linear Functional Models of
     the Rainfall-Runoff Process."  Purdue University Water
     Resources Research Center, Technical Report No. 56,
     West Lafayette, Indiana, 1974.

Reed, L. A.  "Sediment Characteristics of Five Streams
     Near Harrisburg, Pennsylvania, before Highway Con-
     struction." Geological Survey, Open File Report 74-410,
     Harrisburg, Pennsylvania, 1974;  Government Printing
     Office, Washington, D.C., 1976.
                         A-128
-------
Reeves, Mark and Miller, Edward E.  "Estimating Infiltration
     for Erratic Rainfall."  Water Resources Research, Vol.
     11, No. 1, pp. 102-110, 1975.

Remson, I., Fungarolc, A. A. and Lawrence, A. W.  "Water
     Movement in an Unsaturated Sanitary Landfill."  Journal
     of the Sanitary Engineering Division, Proceedings of
     the American Society of Civil Engineers, Vol. 94, SA2,
     pp. 307-317, 1968.

Responses of Fish to Environmental Changes.  W. Chavin, ed.
     Charles C. Thomas, Inc., Springfield, Illinois, 1973.

Rho, J. and Gunner, H. B.  "Micro Floral Response to
     Aquatic Weed Decomposition."  University of Massa-
     chusetts, Department of Environmental Sciences, Am-
     herst, Massachusetts, n.d.

Rickert, D. A., Hines, W. G. and McKenzie, S. W.  "Methods
     and Data Requirements for River-Quality Assessments."
     Water Resources Bulletin, Vol. 11, No. 5, pp. 1013-
     1039, 1975.

Roesner, L. A.  "A Storage, Treatment Overflow and Runoff
     Model for Metropolitan Master Planning."  Applications
     of Stormwater Management Models - 1975, EPA manual,
     1975.

Roesner, L. A.  "Quality Aspects of Urban Runoff."  Water
     Resources Engineers, Walnut Creek, California, n.d.

Roesner, L. A., et al.  "A Model for Evaluating Runoff-
     Quality in Metropolitan Master Planning."  American
     Society of Civil Engineers, Urban Water Resources Re-
     search Program, Technical Memo. No. 23, 1974.

Rogowski, A. S.  "Variability of the Soil Water Flow
     Parameters and their Effect on the Computation of
     Rainfall Excess and Runoff."  International Symposium
     on Uncertainties in Hydrologic and Water Resources
     Systems, Pennsylvania State University, University
     Park, Pennsylvania, n.d.

Rovers, F. A. and Parquhai, A.  "Infiltration and Landfill
     Behavior."  Journal of the Environmental Engineering
     Division, Proceedings of the American Society of Civil
     Engineers, Vol. 99, EE5, pp. 671-690, 1973.
                         A-129
-------
Ross, Hardies, O'Keefe, Babcock and Parsons, Inc.  "EPA
     Authority Affecting Land Use."  Prepared for U.S.
     Environmental Protection Agency, NTIS PB 235 331, 1974.

Ruane, R. J. and Fruh, E. G.  "Effects of Watershed Develop-
     ment on Water Quality."  Journal of the American Water
     Works Association, Vol. 65, No. 5, pp. 358-363, 1973.

Ruskin, A. J., ed.  "Aqueous Environmental Chemistry of
     Metals."  Ann Arbor Science Publishers, Inc., Ann
     Arbor, Michigan, 1974.

Ryden, J. C. , Syers, J. K. and Harris, R. F.  "Nutrient
     Enrichment of Runoff Waters by Soils, Phase 1: Phos-
     phorus Enrichment Potential of Urban Soils in the City
     of Madison."  University of Wisconsin Water Resources
     Center, Madison, Wisconsin, 1972.

Salvato, Joseph A., Jr.  Environmental Engineering and
     Sanitation.  John Wiley and Sons, Inc., New York, New
     York, 1972.

Salvato, Joseph A., Jr.  "Problems and Solutions of Onlot
     Sewage Disposal."  Proceedings of the Second National
     Conference on Individual Onsite Wastewater Systems,
     National Sanitation Foundation, Ann Arbor Michigan, pp.
     39-46, 1976.

Sankowski, Stephen J.  "Magnitude of Frequency of Floods
     in New Jersey with Effects of Urbanization."  U.S.
     Geological Survey, Special Report 38, 1974.

Sarme, P. B. S., Delleur, J. W. and Rao, A. R.  "A Program
     in Urban Hydrology, Part II:  An Evaluation of Rainfall
     Runoff for Small Urbanized Watersheds and the Effect of
     Urbanization on Runoff."  Prepared for U.S. Environ-
     mental Protection Agency, NTIS PB 198 043, 1969.

Sartor, J. D. and Boyd, G. B.  "Water Pollution Aspects of
     Street Surface Contaminants."  A study by the URS Re-
     search Company for the U.S. EPA  (EPA-R2-72-081), Wash-
     ington, D.C., November 1972.

Sartor, J. D., Boyd, G. B. and Agandy, F. J.  "Water Pol-
     lution Aspects of Street Surface Contaminants."
     Journal of Water Pollution Control Federation, Vol. 46,
     No. 3, pp. 458-467, 1974.
                         A-130
-------
Schultz,  J. M.  "Pollutional Characteristics of Stormwater
     Runoff from Urban, Serai-Urban and Rural Watersheds in
     the West Lafayette, Indiana Area."  Purdue University
     Department of Civil Engineering, M.S. Thesis, West
     Lafayette, Indiana, 1969.

Seattle,  Municipality of Metropolitan.  "Maximizing
     Storage in Combined Sewer Systems."  Prepared for the
     U.S. Environmental Protection Agency, 11022 ELK, 1971.

"Sediment Sources and Sediment Yields."  Journal of the
     Hydraulic Division, Proceedings of the American Society
     of Civil Engineers, Vol. 96, HY6, pp. 1283-1329, 1970.

"Sediment Transportation Mechanics:  Erosion of Sediment."
     Journal of the Hydraulics Division, Proceedings of the
     American Society of Civil Engineers, Vol. 88, HY4, pp.
     109-27, 1962.

Selected Urban Storm Water Runoff Abstracts.  U.S. Environ-
     mental Protection Agency, 1968-1970.

Shaheen,  Donald G.  "Contributions of Urban Roadway Usage to
     Water Pollution."  Prepared for the U.S. Environmental
     Protection Agency, EPA report No. 600/2-75-004, 1975.

Shaheen,  D. G.  "Passenger Cars are Big Water Polluters,
     Biospherics Finds.:  Chemical and Engineering News,
     Vol. 51, No. 27, p. 10, July 1973.

Shakla, S. S. and Leland, H. V.  "Heavy Metals: Review of
     Lead."  Journal of the Water Pollution Control Federa-
     tion, Vol. 45, No. 6, pp. 1319-1331, 1973.

Shannon,  E. E. and Brezonik, P. L.  "Relationships between
     Lake Trophic State and Nitrogen and Phosphorus Loading
     Rates."  Environmental Science and Technology, Vol. 6,
     No.  8, pp. 719-725, 1972.

Sikard, L. J. and Keeney, D. R.  "Laboratory Studies on
     Stimulation of Biological Denitrification."  Proceed-
     ings of the National Home Sewage Disposal Symposium,
     American Society of Agricultural Engineers, St. Joseph,
     Missouri, pp. 64-73, 1975.

Singer, P. C.  "Trace Metals and Metal Organic Interactions
     in Natural Waters."  Ann Arbor Science Publishers, Ann
     Arbor, Michigan, 1973.
                         A-131
-------
Snodgrass, William J. and O'Melia, Charles R.  "Predictive
     Model for Phosphorus in Lakes."  Environmental Science
     and Technology, Vol. 9, No. 10, pp. 937-944, 1975.

Soltero, R. A., Wright, J. C. and Horpestad, A. A.  "Effects
     of Impoundment on the Water Quality of the Bighorn
     River."  Water Research (Great Britain), Vol. 7, pp.
     343-354, 1973.

Spiegelman, Robert.  "Review of Techniques of Regional
     Analysis, with Particular Emphasis on Applicability to
     Regional Problems."  Stanford Research Center, Palo
     Alto, California, 1962.

Spooner, C. S., Promise, J. and Graham, P. H.  "A Demonstra-
     tion of Areawide Water Resources Planning for Metro-
     politan Washington,  (Draft)."  EPA, Washington, D.C.,
     n.d.

Sridharan, N. and Lee, G. F.  "Phosphorus Studies in Lower
     Green Bay, Lake Michigan."  Journal of the Water
     Pollution Control Federation, Vol. 46, No. 4, pp. 684-
     696, 1974.

Stankowski, Stephen J.  "Population Density as an Indirect
     Indicator of Urban and Suburban Land-Surface Modifica-
     tions."  U.S. Geological Survey, Geological Survey
     Research Professional Paper 800-B, pp. B219-B224, 1972.

Steinitz, C., et al.  "A Comparative Study of Resource
     Analysis Methods."  Department of LA Research Office,
     GSD, Harvard University, Cambridge, Massachusetts, July
     1969.

Sutherland, R. and McCuen, R., R.  "A Mathematical Model for
     Estimating Pollution Loadings in Runoff from Urban
     Streets."  Preprint from Proceedings of the Interna-
     tional Conference on Mathematical Models of Environ-
     mental Problems, Southampton U.K., 1975.

Sutterlin, A. M.  "Pollutants and the Chemical Senses of
     Aquatic Animals - Perspective and Review."  Chemical
     Senses and Flavor, Vol. 1, pp. 167-178, 1974.

Sylvester, R. 0. and DeWalle, F. B.  "Character and Sig-
     nificance of Highway Runoff Waters, A Preliminary
     Appraisal."  Washington State Highway Commission, Y-
     1441, 1972; NTIS PB 220-083, December 1972.
                         A-132
-------
Tao, P. C. and Delleur, J. W.  "Models of the Stochastic
     and Chronologic Structure, Prediction and Simulation of
     Runoff Sequences - Application to the Lower Ohio
     Basin."  Purdue Water Resources Research Center, West
     Lafayette, Indiana, 1975.

Tarzwell, Clarence M., ed.  "Biological Problems in,Water
     Pollution."  Third Seminar, Robert A. Taft Sanitary
     Engineering Center, Cincinnati, Ohio, 1962.

Task Group Report.  "Sources of Nitrogen and Phosphorus
     in Water Supplies."  Journal of the American Water
     Works Association, Vol. 59, pp. 344-366, 1967.

Terstries, M. L. and Stall, J. P.  "Urban Runoff by Road
     Research Lab Method."  Journal of the Hydraulics
     Division, Proceedings of the American Society of Civil
     Engineers, Vol. 95, HY6, pp. 1809-1834, 1969.

Tholin, A. L. and Keiber, C. J.  "The Hydrology of Urban
     Runoff."  Journal of the Sanitary Engineering Division,
     Proceedings of the American Society of Civil Engineers,
     Vol. 85, SA2, pp. 47-106, 1959.

Thomann, R. J.  Systems Analysis and Water Quality Manage-
     ment.  McGraw-Hill, New York, New York, 1972.

Thompson, G. B., et al.  "Variations of Urban Runoff
     Quality and Quantity with Duration and Intensity of
     Storms - Phase III."  Texas Tech University Water
     Resources Center, Lubbock, Texas, 1974.

Toebes, G. H. and Chang, T. P.  "Simulation Model for the
     Upper Wabash Surface Water System."  Purdue University
     Water Resources Research Center, West Lafayette,
     Indiana, 1973.

Torno, H. C.  "A Model for Assessing Impact of Stormwater
     Runoff and Combined Sewer Overflows and Evaluating
     Pollution Abatement Alternatives."  Water Research
      (Great Britain), Vol. 9, pp. 849-852, 1975.

Tourbier, Joachim.  "Water Resources as a Basis for Compre-
     hensive Planning and Development of the Christina River
     Basin."  Prepared for U.S. Department of the Interior
     by Water Resources Center, University of Delaware,
     Newark, Delaware, 1973.
                         A-133
-------
Tourbier, J. and Westmacott, R.  "Water Resources Protection
     Measures in Land Development" - A Handbook, Water
     Resources Center, University of Delaware, Newark, Dela-
     ware, pp. 14-16, April 1974.

Tuffey, T. J., Hunter, J. V. and Matulewich, V. A.  "Zones
     of Nitrification."  Water Resources Bulletin, Vol. 10,
     No. 3, pp. 555-564, 1974.

Turner, Collie and Braden, Inc.  "Storrnwater Management
     Report."  (Draft)  Prepared for New Castle County,
     Delaware by Turner, Collie and Braden, Inc., Houston,
     Texas, 1975.

URS Research Company.  "Water Quality Management Planning
     for Urban Runoff."   (Draft)  Prepared for U.S. En-
     vironmental Protection Agency, Contract No. 68-01-1846,
     August 1964.

Urban Land Institute.  "Residential Stormwater Model."
     Washington,  D. C.

"Urban Hydrology for Small Watersheds."  U.S. Department
     of Agriculture, Soil Conservation Service, Central
     Technical Unit, Hydrology Technical Note 1, 1973.

Urban Stormwater Management Modeling and Decision Making.
     Prepared for National Environmental Research Center by
     Florida University, PB 242-290, 1975.

Urban Systems Research and Engineering, Inc.  "Evaluation
     of the Use of Existing and Modified Land Use Instru-
     ments to Achieve Environmental Quality."  Urban Systems
     Research and Engineering, Inc., Cambridge, Massachu-
     setts, 1975.

U.S. Department of Agriculture.  "Predicting Rainfall-
     Erosion Losses from Cropland East of the Rocky Moun-
     tains."  Agricultural Research Service, Agriculture
     Handbook No. 282, 1965.

U.S. Department of Agriculture, Soil Conservation Service.
     "Soil Survey - Montgomery County, Pennsylvania."
     Government Printing Office, Washington, D.C., 1967.

U.S. Environmental Protection Agency.  "Characterization and
     Treatment of Urban Land Runoff."  EPA 670/2-74-096,
     December 1975.
                         A-134
-------
U.S. Environmental Protection Agency.  "Methods for Identi-
     fying and Evaluating the Nature and Extent of Nonpoint
     Sources of Pollutants."  EPA-430-73-014, Washington,
     D.C., 1973.

U.S. Department of Housing and Urban Development.  "Urban
     and Regional Informations Systems."  Government Print-
     ing Office, Washington, D.C.

Uttormark, Paul D.,  Chapin, John D. and Green, Kenneth M.
     "Estimating Nutrient Loadings of Lakes."  Water Re-
     sources Center, EPA 660/3-74-020, Madison, Wisconsin,
     1974.

Vice, R. B., Guy, H. P. and Ferguson, G. E.  "Sediment
     Movement in an Area of Suburban Highway Construction,
     Scott Run Basin, Fairfax County, Virginia."  U.S.
     Geological Survey, Water Supply Paper 1591-E, 1969.

Viessmar, W.  "Assessing the Quality of Urban Drainage."
     Public Works, Vol. 100, No. 10, pp. 89-92, 1969.

Vitale, A. M. and Sprey, P. M.  "Total Urban Water Pollution
     Loads:  The Impact of Stormwater."  Prepared for U.S.
     Environmental Protection Agency by Enviro Control,
     Inc., Rockville, Maryland, NTIS PB 231 730, 1974.

Walker, W. G., et al.  "Nitrogen Transformations During
     Subsurface Disposal of Septic Tank Effluent in Sands I:
     Soil Transformations."  Journal of Environmental Qual-
     ity, Vol. 2, pp. 475-480, 1973.

Walker, W. G., et al.  "Nitrogen Transformations During
     Subsurface Disposal of Septic Tank Effluent in Sands
     II:  Ground Water Quality."  Journal of Environmental
     Quality, Vol. 2, pp. 521-525, 1973.

Walker, William H.  "Groundwater Nitrate Pollution in Rural
     Areas."  Ground Water, Vol. 11, No. 5, pp. 19-22, 1973.

Wall, J. P., et al.   "Wisconsin Lakes Receiving Sewage
     Effluent."  Wisconsin Water Research Center, Technical
     Report 73-1, EPA R-801-863, 1973.

Wallace, Douglas A.  and Dague, Richard R.  "Modeling of
     Land Runofi Effects on Dissolved Oxygen,"  Journal of
     the Water Pollution Control Federation, Vol. 45, Mo. 8,
     pp. 1795-1809,  1973.
                         A-135
-------
Wallis, I. G.  "Options for Improving Water Quality."
     International Journal of Environment Studies, Vol. 6,
     pp. 107-120, 1974.

Warner, Maurice L. and Preston, Edward H.  "A Review of
     Environmental Impact Assessment Methodologies."  Pre-
     pared for U.S. Environmental Protection Agency, Office
     of Research, EPA 600/5-74-002, April 1974.

"Waste Lube Oils Pose Disposal Dilemma."  Environmental
     Science and Technology, Vol. 6, No. 1, p. 25, 1972.

"Water Pollution Aspects of Urban Runoff."  Prepared for
     the Federal Water Pollution Control Administration,
     U.S. Department of Interior, by the American Public
     Works Association, Government Printing Office, Wash-
     ington, D.C., 1969.

"Water Quality Criteria 1972."  Ecological Research Series,
     R3.73.033, Washington, D.C., March 1973.

"Water Quality Management for Urban Runoff."  U.S. Environ-
     mental Protection Agency.  NTIS PB 241 689.

"Water Quality Management Planning for Urban Runoff."  U.S.
     Environmental Protection Agency, EPA 440/9-75-004,
     1975.

"Water Quality Models for Urban and Suburban Areas."
     Prepared for U.S. Environmental Protection Agency, NTIS
     PB 238 622, University of Nebraska, Lincoln, Nebraska,
     1974.

Water Resources Center, University of Delaware.  Water
     Resources Protection Measures in Land Development - A
     Handbook.  University of Delaware Water Resources
     Center, 1974.

Water Resources Council.  "A Summary Analysis of 19 Tests
     of Proposed Evaluation Procedures on Selected Water and
     Land Resources Projects."  1970.

Weibel, S. R., Anderson, R. J. and Woodward, R. L.  "Urban
     Land Runoff as a Factor in Stream Pollution."  Journal
     of the Water Pollution Control Federation, Vol. 36, No,
     7, pp. 914-924, 1964.
                         A-136
-------
Weibel, S. R.  "Urban Drainage as a Factor in Eutrophica-
     tion."  Eutrophication:  Causes, Consequences, Correc-
     tives.  Proceedings of a Symposium, National Academy of
     Sciences, Washington, D.C., 1969.

Weibel, S. R., et al.  "Pesticides and Other Contaminants
     in Rainfall and Runoff."  Journal of the American Water
     Works Association, Vol. 58, No. 8, pp. 1075-1084, 1966.

Weibel, S. R., et al.  "Treatment of Urban Stormwater
     Runoff."  Journal of the Water Pollution Control Feder-
     ation, Research Supplement, Vol. 40, No. 5, Part 2, R
     162-R170, 1968.

Welb, D. M., et al.  "Variation of Urban Runoff Quality with
     Duration and Intensity of Storms - Phase II."  NTIS No.
     PB-223 930, 1973.

Werner, R. G.  "Water Quality-Limnological Concerns about
     Forest Fertilization."  Forest Fertilization Symposium
     Proceedings, College of Engineering Science and Forestry,
     S.U.N.Y. Warrensburg, New York Campus, 1973.

Werschmeir, W. H. and Smith, D. D.  "Predicting Rainfall
     Erosion Losses from Cropland East of the Rocky Moun-
     tains."  Agricultural Handbook 282, U.S. Government
     Printing Office, Washington, D.C., 1965.

Weston, Roy F., Inc.  "Combined Sewer Overflow Abatement
     Alternatives."  Prepared for U.S. Environmental Pro-
     tection Agency by Roy F. Weston, Inc., West Chester,
     Pennsylvania, 11024 EXF, 1970.

Weston, Roy F., Inc.  "Lancaster County Planning Commission
     Storm Drainage Study."  Roy F. Weston, Inc., West
     Chester, Pennsylvania, 1970.

Whipple, William Jr.  "Urban Runoff:  Quantity and Quality."
     Proceedings of a Research Conference at Rindge, New
     Hampshire, American Society of Civil Engineers, New
     York, New York, 1974.

Whipple, William Jr., ed.  "Urbanization and Water Quality
     Control."  American Water Resources Association, Min-
     neapolis, Minnesota, 1975.
                         A-137
-------
Whipple, William Jr.,  et al.  "Unrecorded Pollution and
     Dynamics of Biochemical Oxygen Demand."  Rutgers
     University, Water Resources Research Institute, New
     Brunswick, New Jersey, 1974.

Whipple, William Jr. and Hafschmidt, M. M.  "Reorientation
     of Urban Water Resources Research."  Rutgers University
     Water Resources Research Institute, New Brunswick, New
     Jersey, 1976.

Whipple, W. Jr. and Hunter, J. V.  "Non-Point Sources and
     Planning for Water Pollution Control."  Presented at
     the 48th Annual Water Pollution Control Federation
     Convention, Miami Beach, Florida, 1975.

Whipple, W., Hunter, J. V. and Yu, S. L.  "Unrecorded
     Pollution from Urban Runoff."  Journal of Water Pol-
     lution Control Federation, Vol. 46, No. 3, pp. 873-885,
     1974.

Wilber, William G. and Hunter, Joseph V.  "Contributions of
     Metals Resulting from Stormwater Runoff and Precipita-
     tion in Lodi, New Jersey."  American Water Resources
     Association, pp.  45-58, June 1975.

Wilber, William A. and Hunter, Joseph V.  "Heavy Metals
     in Urban Runoff."  Rutgers University Department of
     Environmental Science, New Brunswick, New Jersey, 1975.

Wiley, Morris A.  The Petroleum Industry and Cost Effective
     Water Quality Planning: I:  Assessments of PL  92-500
     and II:  Improvement of Cost Effectiveness.  Presented
     at a Symposium on Urbanization and Water Quality
     Control at Rutgers University, New Brunswick,  New
     Jersey, 1975.

Williams, J. R.   "Sediment Yield Prediction with Universal
     Equation Using Runoff Energy Factor."  USDA Resource
     Service, Oxford, Mississippi, November 28-30,  1972.

Williams, J. R. and Berndt, H. D.   "Sediment Yield  Computed
     with Universal Equation."  Journal of the Hydraulics
     Division, Proceedings of the American Society  of Civil
     Engineers, Vol. 98, HY12, pp.  2087-2098, 1972.
                         A-138
-------
Williams, L. G., Joyce, J. C. and Monk,  J.  T.  Jr.   "Stream-
     Velocity Effects on the Heavy Metals Concentration."
     Journal of the American Water Works Association,  Vol.
     65, No. 4, pp. 275-279, 1973.

Williams, J. R.  "Sediment Routing for Agricultural Water-
     sheds."  Water Resources Bulletin,  Vol.  11, No.  5,  pp.
     965-974, 1975.

Wischmeier, W. H., Johnson and Cross.  "A Soil Erodibility
     Nomograph for Farmland and Construction  Sites."
     Journal of Soil Water Conservation, Vol.  26,  pp.  189-
     193, 1971.

Wischmeier, W. H. and Smith, D. D.   "Rainfall  Energy and
     its Relationship to Soil Loss."  Transactions of  the
     American Geophysical Union, Vol. 39, No.  2, 1958.

Wolman, G. Gordan.  "Stream Standards:   Dead  or Hiding?"
     Journal of the Water Pollution  Control Federation,  Vol.
     46, No. 3, 1974.

Wolman, M. G. and Schick, A. D.  "Effects of  Construction
     on Fluvial Sediment: Urban and  Suburban  Areas of  Mary-
     land."  Water Resources Research, Vol. 3,  No.  2,  pp.
     451-462, 1967.

Wulkowicz, G. M. and Saleem, Z. A.   "Chloride  Balance  of
     an Urban Basin in the Chicago Area."   Water Resources
     Research, Vol. 10, No. 5, pp. 974-982, 1974.

Yen, Ben Chie.  "Methodologies for Flow  Prediction in
     Urban Storm Drainage Systems."  Prepared  for  U.S.
     Environmental Protection Agency, NTIS  PB  225-480,  1973,

Young, R. A. and Wiersma, J. L.  "The Role  of  Rainfall
     Impact on Soil Detachment and Transport."  Water  Re-
     sources Research, Vol. 9, No. 6, pp. 1629-1636,  1973.

Young, C. E.  Current Research on Land Application of
     Waste Water and Sludge.  Penn State University,  Insti-
     tute for Research on Land and Water Resources,  Uni-
     versity Park, Pennsylvania, 1975.

Yu, S. L., Whipple, W. and Hunter, J. V.  "Assessing
     Unrecorded Organic Pollution from Agricultural, Urban
     and Wooded Lands."  Water Research  (Great Britain),
     Vol. 9, pp. 849-852, 1975.
                          7i_1 TQ       ftU.S. GOVERNMENT PRINTING OFFICE: 1976 7ZO-117/87<)i
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