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Description
San Bruno City Council Meeting July 27, 2010 10g. Purchase Water Tank Mixers
A
B
The
only
way
to
remove
the
high
nitrate
levels
from
the
water
in
the
tanks
is
to
completely
drain
all
the
water
out
of
the
tanks
then
pump
new,
fresh
water
back
into
them.
This
method
is
wasteful
and
costly
to
the
city.
The
acquisition
of
seven
active
take
mixtures
will
stop
the
nitrification
and
low
distant
production
problems
that
have
happened
through
thermal
stratification
during
the
summer
and
late
fall
months.
B
I'll
distract:
how
does
stratification
happen
during
the
warmer
times
of
the
year?
Direct
sunlight
shines
on
homogenous
tank
during
the
tent
turning
the
tank
into
a
thermo
stratified
tank
with
the
warmer
water
on
top.
This
creates
a
bear
barrier
that
prevents
the
disinfectant
chemical
from
entering
the
top
layer
of
the
tank.
This
creates
difficulty
had
taken
a
good
quality
example
from
the
top
of
the
tank
where
sample
site
1
is
located.
B
B
B
For
one
instance,
I
at
2006
very
with
CD,
install
two
packs
tanks,
tank
mixer
in
there
Cambridge
number
two
tank,
a
half
million
gallon
tank
before
they
installed
the
mixer.
The
top
layer
over
the
water
in
the
tank
had
virtually
no
disinfectant
residual
in
a
high
night
in
and
had
high
nitrate
levels.
Redwood
City
never
had
another
water
quality
issue
at
the
Cambridge
number
two
tank
after
the
mixture
was
installed
on
July
19
2006.