ILLINOIS POLLUTION CONTROL BOARD
May
26,
1971
In the matter of
OHIO RIVER TREATMENT DATES
)
#R71-3
Opinion of
the Board
(by
Mr. Dumelle)
This rule making was proposed by
Mr.
Currie on February
3,
1971
and sought
to do for the Ohio River what was previously
accomplished.
on the Mississimpi
River.
The proposed amendment sought to change
the existing regulation
(SWB—lO)
to accelerate
the target dates by
which secondary treatment of sewage would be required and
it
sought
to
more precisely delineate and define those factors which constitute
secondary treatment.
The new regulation after amendment requires
any municipality or industry which discharges
its wastes into
the
Ohio River to provide
a minimum of secondary treatment for that
effluent
by
December
31,
1973.
Before amendment the dates were stretched
out:
to December 1977.
The
1977
date is
a more distant deadline
for
secon--
darv treatment than
any
others elsewhere
in the
State.
The existing regulation
is
contained
in
the cçmprehensive SUB—10
entitled
Water
Quality
Standards,
:rnterstate
Waters,
Ohio
River
and
5aiine
River,
which
was approved by the
Sanitary Water Board
(SWB)
one
of
this
Board’s
predecessors,
in
December
1968,
The
reciulation
tnc~udes
an
implementation
plan
thice
detais
how
wastes
discharc~ed
into
the
Ohio
River
interstate
waters
are
to
he
treated.
Bowever
before
amendment
the
snecifications
regarding
secondary
treatment
were
less
specific
than
the”
are
now.
A
public
hearing
was
held
on
April
22,
1971
at
the
Dixon
Snrinas
Experimental
Station
at
which
it
was
toned
that
the
diochargers
affected.
by
the
regulation
would
apoear
and
discuss
cossible
anticipated
difficulties
and
would
testify
as
to
ate
status
of
their
treatment
facilities.
As
none
of
the
affecoed
nunicipalities
anpeared,
we
are
relying
on
the
submission
of
the
Eriviren.menta.l
Protcacticn
Ape:ncv
\eency)
as
to
possible
difficulties
of
plants
on
the
river
in
meeting
the
now
deadlines,
It
appears
that
no
Tnuniciaoiitv
should
have
‘:nusoal
dilti—
culty
in
complyine
with
the
new
deadline
date
alttoiich
the
Acency
indacated
that
the
C:i.ties
of
ladoc
ant
Detropolis
would
be
burdened.
The
guesticn
of
the
necessity
for
repuirinq
secondary
treatment
by
an
accelerated
date
was
dealt
~‘ith
at
Length
at
boti
thos
Boaro
s
hearing
on
a.
similar
mjrooosai
for
the
yiosissippi
River
(R,7O—3,
Exhibit
1)
and
by
the
Ohio
River
\Jallev
Sanitatiomi Oomniission
(Exuibit
2)
Many
of
the
considerations
which were acolicabie
to
the
Mississonti
River
are
also
cogent
for
the
Ohio
River.
that
was
said
reqardino
the
‘1
•—
640
efficacy of secondary
treatment on the Mississippi River is germane
to
the present consideration.
Conventional secondary treatment of
municipal wastes accomplishes one or more of the following purposes:
Reduces disease~-producingand other enteric bacteria
and
viruses;
(2)
Reduces depletion of oxygen
in the
receeivinq water by
oxidizing and removing many
of
the
substances
that
consume oxygen;
(3)
Reduces visible and otherwise aesthetically disagreeable
sewage materials;
(4)
Reduces specific substances
in municipal wastes, by physical
and chemical change, that otherwise will be dangerous to
humans,
animals,
or fish exposed to the contaminated
water
(Ex.l, p.91—92)
The Ohio River Valley Water Sanitation Commission
(ORSANCO)
is an interstate agency established with
the approval of Conaress
and by legislative action of
the eight states
in the Ohio
Valley.
The states are Illinois,
Indiana, Kentucky, New York,
Ohio, Penn--
sylvania, West Virginia,
and Virginia.
ORSANCO held
a hearing on
September
16,
1970 whose purpose was
as was
the Board’s in this case~
to obtain information
and other evidence
for use
in determining the
degree of treatment which should be required for sewace and industrial
wastes discharged into
the Ohio River,
The State
of Illinois endorsed
the
proposed standards
at
that public hearing,
With
the
enactment of
water
quality standards
in
November,
1970 following
the
hearing,
ORSANCO has effected
a policy decision
of
requiring
secondary
treatment
for all discharges
(Exhibit
2,
~.
20--22),
The BOB standard adopted by ORSANCO is not phrased in the form
of effluent standard criteria but is stated in terms of percentage
removal and basically requires
92
removal of 5-day BOB,
Apparently
the
ORSANCO standard and
that
now
adopted
by this Board are none
too
tough~
In
testimony
submitted
at
the
ORSANCO hearing,
the
United
States Atomic
Energy
Commission
commented that the recommended
BOB
standard
might
not
be
sufficiently restrictive,
The
Agency
stated
that
it
employed
the
following criteria
to
determine the acceptability
of
water quality
from
waste treatment plants:
Biochemical oxygen
demand
-
10
ppm
maximum;
Suspended
solids
-
15
ppm
maximum; Residual
chlorine
-
detectable
(Ex,2,
doe,
8)
In other testimony at the Ohio hearing the FWQA
(now the Water
Quality Office of
the Federal Environmental Protection Agency)
endorsed
a standard of
a minimum of
90
reduction of BOB
for the summer months
and stated that the agency could not endorse the 75
removal requirement
for the Winter months,
The FWQA proposed that
the 75
figure be
changed to
85
(Ex.2, doc.7),
The Steel Industry Action Committee
endorsed
a BOD effluent standard of 20 mg/i and
a suspended solids
effluent standard of
25
mg/l
(Ex.2, doc.lO)
,
There was
no
significant
testimony which rebutted the implication in the last statement,
that
the technical feasibility of achieving the standard was beyond question.
I
—
641
At this
point in our history
it
seems almost as anachronistic to
speak about
the technical feasibility of secondary treatment
as
it does
the desirability or necessity of secondary treatment of wastes,
Nonethe-
less
the
Act
which created the Board directed
it to consider the economic
reasonabless and technical
feasibility of rules which
it sought to
enact,
The dilution concept for the treatment of wastes was
the principal
thinking in our society for
a very long time,
Until
the end of the 19th
century,
raw sewage was discharged directly
into water bodies and puri-
fied through natural processes by the flowing stream.
This worked sat-
isfactorily only where
the receiving waters had
a large dilution capacity
and
the effluents were relatively small.
It is virtually impossible
to
find such
a situation anywhere in our country today and waste treatment
is consequently required.
Today,
treatment of municipal wastes by
what is called primary and secondary treatment is the most common form
of pollution control in the U,S,
Primary treatment has been
a reality along
the length of
the Ohio
River for some decades
now,
The compulsion for secondary treatment is
a relatively recent development.
In primary treatment solids are
allowed to settle and are
then removed from the plant influent,
Secon-
dary treatment is basically
a biological operation
in which bacteria
react with the putrescrible organic colloidal or dissolved material
by absorption,
digestion, oxidation, assimilation,
and decomposition.
Results of the operation are settleable organic particles
or inert
mineral substances,
Trickling filters and activated sludge plants are
the
two most common types of secondary treatment and both of these
processes
talce place
in the presence of oxygen
(aerobic)
The trickling filter uses
a bed of crushed stone or other coarse
material over which the effluent from the primary treatment is distributed.
The stones become covered by slime
(biological growths) which represent
the active agent in the ahsorntion or reduction of the pollutant.
Oxygen
is supplied by the circulating air.
The results of
the biochemical action
are washed out and carried by
the liquid to the settling basin.
In the activated sludge process,
the primary effluent enters
a
tank and
is mixed with
a quantity of returned sludge from the final
settling basin,
This returned sludge
is rich with biological growth
since it has gone through the process previously,
Air
is bubbled into
the
tank with various devices.
After the biological action has taken
place the particles are simply settled,
Either the activated sludge
or trickling filter process can have any number of modifications and
refinements which can improve the efficiency and degree of treatment
but the basic operations are essentially
as dedcribed,
Historically, secondary treatment has often been spoken about as
complete treatment.
This is obviously not accurate
as none
of the
methods of secondary treatment accomplishes total removal.
The
increasing necessity and demand for clean water
is increasing the demand
for what
is variously called advanced waste treatment, tertiary, or
third--stagetreatment.
Briefly,
the aim of tertiary treatment is to
I
—
642
achieve purity levels of
98 and 99
of SOD and suspended solids
removal.
Some of the methods employed are nothing more
than refined
and improved secondary processes.
Additional treatment methods
such as chemical treatment and electro-chemical methods could also
be used.
The Hanover experimental tertiary plant of the Metropolitan
Sanitary District uses coagulation, rapid
sand filters,
or micro—
straining.
In our decision and adoption of
the amended regulation
today we
are not requiring any of the tertiary treatment processes;
we are simply requiring acceleration of the achievement of secondary
treatment.
The economic reasonability in requiring secondary treatment
is
basically the cost of treatment balanced against the public benefit
to be derived from such treatment,
In this case,
as in the Mississippi
River case,
in determining
“economic reasonabless” we need not balance
the total cost of secondary treatment against the benefits
to be
derived but rather whether the additional cost,
if any, which would be
incurred as
a result of
the accelerated date by which the treatment
is
required
is reasonable
as compared against the benefits
to be accrued
in having the wastes treated by the earlier date.
The Regulation which was proposed on February
3,
1971
and adopted
by
the Board simultaneously with this opinion provides essentially as
follows:
(1)
all oxygen—demanding wastes
and wastes containing suspended
solids shall receive secondary treatment,
at
a minimum,
by
December
31,
1973;
(2)
for sewage works with
a Population Equivalent
(P.E.)
of
10,000 or more,
secondary treatment shall mean 90
removal
of SOD5 and suspended
solids,
and no more than
20 mg/l of
SOD5
and
25 mg/l
of suspended solids;
(3)
for sewage works with
a P,E. of
less than 10,000
secondary
treatment shall mean
85
removal of BOB5
and suspended
solids and no more than
30
mg/l of BOB5
and
37
mg/l
of
suspended solids;
and
(4)
disinfection
shall be
provided
for effluents to reduce
fecal coliforms
as follows:
(a)
400 per
100 ml in primary contact waters,
and
(b)
2000 per 100 ml
in all other waters.
The principal difference
in the amendment as compared to the former
directive
in SWB-lO
is,
of course,
the advancement
of
the date by
which secondary treatment facilities are required.
The regulation makes
uniform throughout
the
Ohio
River Basin the date
by
which
such
treat-
ment is required.
All
users
of
the River as the outlet
for their
discharges shall be
bound
by the same requirement.
We
hope that the
other states will adopt consistent standards
so that discrimination
does
not exist between those
on
one side of
the River and those on
the
other,
1
—643
The new regulation refers
to all
waste discharges, thereby not
giving specific reference
to municipal discharges
as did paragraph
7 of Rule 1.08 of SWB—l0,
Paragraph
8 of SWB—lO directed that industry
furnish that degree of treatment “equivalent”
to
that furnished by the
municipalities.
The Agency has informed us that t~eintent of the
proposed regulation was that it apply to industry and municipality alike.
To avoid any ambiguity in this regard we have therefore phrased the
new regulation in terms of
“all waste discharges.”
We have included
under the term “discharges,” both oxygen—demanding discharqes and those
containing suspended solids,
The regulation therefore also covers those
industries which may discharge wastes which are of a non-organic
nature.
We have also incorporated
a minimum—size exclusion into
the new
regulation,
Those sewage works receiving
a waste discharge equal
to
or greater than 10,000 population equivalents
(P.E.) must attain a
90
reduction in SOD5
those less than 10,000 P,E. need only reach
an 85
reduction.
The basis for
such
a differentiation lies in the
type of secondary treatment facilities employed.
With the activated
sludge process,
a 90
reduction rate is attainable; with the trickling
filter method, however, only 85
is generally possible.
The trickling
filter’, though,
is
a more suitable method of treatment for smaller
plants since it does
not demand the extensive testing,
the constant
overseeing,
or
the
highly—trained
personnel
that
an
activated
sludge
plant would require.
In addition,
the activated sludge process is
more expensive to install.
ORSANCO has suggested
a 92
reduction rate
all
along
the River,
We
have
also
repealed
paragraphs
11(a)
and
(b)
of
Rule
1.08.
The
effluent standard for fecal coliform reduction to 400 per 100 ml or less
before discharge
to any waters designated
for primary contact and the
requirement for bypass flows in excess of sewage works capacity have
been retained in the amended regulation.
We have added the requirement
that
disinfection
reduce
fecal
coliforms
to
2000
per
100
ml
before
discharge to any waters other than those designated for primary contact.
Further,
the wording in the new regulation removes any doubt as to
whether the bacteria standard is in fact an effluent standard.
In all
other aspects,
the numbers have been transposed
to the new regulation
and
a constant proportion has been maintained in the numerical value
of the reduction demanded.
It should be noted that both the effluent standard and the reduc-
tion percentage must be met by all
waste
dischargers.
This is especially
applicable to industrial wastes.
Thus,
an industry with greater than
10,000 P,E, must attain
a 90
reduction
in
suspended solids and BOD and
an effluent which contains no more than 25 mg/l of suspended solids and
no more than 20 mg/l of SOD.
There is ample basis within the criteria established by the
Environmental Protection Act for the promulgation of the amended regula-
tion.
The necessity of
a closer deadline was shown.
Today~s regulation
forms
a vital portion of
the Board’s dedication to the principle of
non-degradation of the waters
of Illinois.
The State legislature has
‘&rected
the
Board to act as expeditiously
as possible to abate water
1
—
644
pollution and this regulation as was the change of dates on the
Mississippi River imposing a December 31,
1973 deadline is drawn
in
that spirit.
I concur:
I
dissent~
I,
Regina
B.
Ryan,
Clerk
of
the
Illinois
Pollution
Control
Board,
certify
that
the
Board
approved
this
Opinion
on
26,dav,
May,
1971.
trol Board