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lnstead of limiting the amount of pollution discharged into a river or lake, dilution of
the pollution is sometimes employed to meet standards requiring no more than a certain concentration of pollutants in a given amount of water. This means allowing
more than the standard concentration in a mixing zone, where the pollution is diluted. The industrial ettluent shown illustrates how waste mixes with more and more
water and becomes less and less visible as it moves tarther away from the plant.
Formulas based on the turbulence of a given stream and other relevant factors are
used to calculate the mixing zone.
example, whether waste discharges from a proposed industrial plant will raise
pollution levels above the established standards. Although longitudinal mixing in particular can extend far downstream from the point of discharge, the
area of most intense mixing is adjacent to the discharge pipe. This no man’s
land of high pollution is one price that must be paid for disposing of wastes in
\\'atei'\va_vs, a problem stressed at the Lake Michigan conference session on
March 23, 1911 by Donald I. Mount, Director of the National Water Quality
Duluth, Minnesota:
A mixing zone las used for regulatory purposes] I feel by denition is a place
where rece1vmg water standards are not met. That is. the conditions are less
than we are str1vmg to achieve in the receiving water.
.
.
.
So the question YOU
ult11nately come to is how much sin is acceptable?
"lËe
answer depends upon who is being questioned.
comment
specr
concerned the degree to which heated cooling water from power
and other industries should be permitted to warm Lake Michigan. In( llbtl}lîl11€pl'€S€lïtàtl\"€S
argued that there was no “sin,” since heated eiuents
w \
…
'
.
-
.
—
ha1m to the lake. Invest1gators from the L .S. Fish
an
>
.
-
r’ —
.
,
.
.
Ht i 1ic
5c1\1ce, on the other hand, foresaw serious damage to aquat1c
1>'
-'.)1‘.)'
-'…
-
-
.
.
c anc
an mcr
casc … eutroplncat10n if anything but shghtlv heated efuents
\\‘Cre permitted.
'
10
Assault on a Lake
l
,
*
äkäêî
: \”
‘
,
.
;
——u—.
-
ï
.‘L;.
.
.
-…
_…
-—
'
“
’
.
_,
__
—
,
,
"
n
…
,:
.
.
'
_
‘
_
…."=
:
-
"
â
-
"
\.
__
'
!
…
*,m
lnstead of limiting the amount of pollution discharged into a river or lake, dilution of
the pollution is sometimes employed to meet standards requiring no more than a certain concentration of pollutants in a given amount of water. This means allowing
more than the standard concentration in a mixing zone, where the pollution is diluted. The industrial ettluent shown illustrates how waste mixes with more and more
water and becomes less and less visible as it moves tarther away from the plant.
Formulas based on the turbulence of a given stream and other relevant factors are
used to calculate the mixing zone.
example, whether waste discharges from a proposed industrial plant will raise
pollution levels above the established standards. Although longitudinal mixing in particular can extend far downstream from the point of discharge, the
area of most intense mixing is adjacent to the discharge pipe. This no man’s
land of high pollution is one price that must be paid for disposing of wastes in
\\'atei'\va_vs, a problem stressed at the Lake Michigan conference session on
March 23, 1911 by Donald I. Mount, Director of the National Water Quality
Duluth, Minnesota:
A mixing zone las used for regulatory purposes] I feel by denition is a place
where rece1vmg water standards are not met. That is. the conditions are less
than we are str1vmg to achieve in the receiving water.
.
.
.
So the question YOU
ult11nately come to is how much sin is acceptable?
"lËe
answer depends upon who is being questioned.
comment
specr
concerned the degree to which heated cooling water from power
and other industries should be permitted to warm Lake Michigan. In( llbtl}lîl11€pl'€S€lïtàtl\"€S
argued that there was no “sin,” since heated eiuents
w \
…
'
.
-
.
—
ha1m to the lake. Invest1gators from the L .S. Fish
an
>
.
-
r’ —
.
,
.
.
Ht i 1ic
5c1\1ce, on the other hand, foresaw serious damage to aquat1c
1>'
-'.)1‘.)'
-'…
-
-
.
.
c anc
an mcr
casc … eutroplncat10n if anything but shghtlv heated efuents
\\‘Cre permitted.
'
10
Assault on a Lake