IN THE MATTER OF:

Petition ofNoveon, Inc.

for an Adjusted

Standard from

35

Iii. Adm. Code 304.122

)

)

)

)

)

)

)

CLERK’S OFFICE

FEB

-

62004

DorothyM.

Gunn, Clerk

Illinois Pollution Control Board

James R. Thompson Center

100 West Randolph Street

Suite 11-500

Chicago, IL

60601

Deborah Williams

Assistant Counsel

Division ofLegal Counsel

Illinois Environmental Protection

Agency

1021 N. Grand Avenue East

Springfield,

IL

62794-9276

BradleyP. Halloran

Hearing Officer

Illinois Pollution ControlBoard

James R. Thompson Center

100 West Randolph Street

Suite 11-500

Chicago, IL

60601

PLEASE

TAKE

NOTICE

that

on

Friday,

February

6,

2004,

we

filed

the attached

Expert Written Testimony ofMichael R. Corn, P.E.

with the Illinois

Pollution Control Board,

a

copy ofwhich is herewith served upon you.

Respectfully submitted,

NOVEON, INC.

Richard J. Kissel

Mark Latham

Sheila H. Deely

GARDNER CARTON & DOUGLAS

LLP

191 N. Wacker Drive

—

Suite 3700

Chicago, IL

60606

312-569-1000

By:

One ofIts Attorne

s

BEFORE THE

ILLINOIS POLLUTION CONTROL BOAR~TATEOF

ILLINOIS

~

Control Board

AS

THIS FILING IS SUBMITTED ON RECYCLED PAPER

---

RECE

WED

BEFORE

THE

ILLINOIS POLLUTION

CONTROL BOA1~1i~ERK’S

OFFICE

IN

THE MATTER

OF:

)

STATE

OF

ILUNOIS

Petition ofNoveon, Inc.

)

Pollution Control

Board

)

AS 02-5

)

for an Adjusted Standard from

)

35111. Adm. Code 304.122

)

EXPERT WRITTEN TESTIMONY

OF

MICHAEL

1.

INTRODUCTION

This

Expert

Written

Testimony

is

submitted

to

the

Illinois

Pollution

Control

Board in connection with the Petition for Adjusted

Standard before the Illinois Pollution

Control

Board

entitled Noveon,

Inc.

versus Illinois

Environmental

Protection

Agency,

PCB

as

02-5.

2.

QUALIFICATIONS

AND EXPERIENCE

I am the

President

and

a

Technical

Director of

AquAeTer, Inc.,

(AquAeTer),

located

in

Brentwood,

Tennessee.

AquAeler

has three

offices, one

of which

is

the

Brentwood

office,

and

a staff of about

25

professionals.

In my

technical

role

for the

company,

I

serve

as

the

chief water

quality

monitoring,

modeling

and

permitting

engineer.

As

such, I

direct our projects in

dispersion

monitoring

and

modeling,

water

quality

monitoring

and

modeling,

including

total

maximum

daily

load

analyses,

contaminant transport, fate and effects monitoring and modeling.

I

have

approximately

28

years

experience

in

environmental engineering

and

I

have worked in most

states and

in 20

foreign countries.

I have participated or directed

water quality

studies on over 200 streams, rivers, lakes, estuaries, and oceans in both the

U.S.

and in foreign countries.

I have actively directed dispersion studies and regulatory

interpretations of mixing

zones

on

over

55

water bodies

in 21

states

and three foreign

countries.

I

have

presented

expert

opinions

and

have

given

expert testimony

on

mixing

zones

in

Connecticut and

Illinois.

I

have

given an

expert opinion before

the

Illinois

Pollution Control Board (Board) in Chicago, Illinois on the theory and the size ofmixing

zones

in

proposed

Illinois

Environmental

Protection

Agency

(IEPA)

mixing

zone

regulations.

The

Board

agreed

with

the premise

I

put

forward

and

a

minimum

size

limitation of 1,000

square

feet for a Zone of Initial Dilution (ZID),

as proposed by

the

Illinois Environmental Protection Agency IEPA, was removed from the regulations.

1

---

I hold a Bachelor of Science

Degree (B.S.)

from the University of Tennessee in

Nuclear Engineering and a Master of Science Degree (M.S.)

from Vanderbilt University

in Environmental and Water Resources Engineering.

My resume is

attached, including

expert opinion or testimony

given

on

mixing

zones.

3.

DESCRIPTION OF

EFFLUENT AND RIVER

Effluent Flow and Characteristics

The Noveon facility at Henry has an average effluent flow of 0.8

million gallons

per day (mgd) or 1.24

cubic feet per second (cfs) and a maximum flow of

1.35

mgd or

2.09 cfs.

The wastewater treatment facility provides treatment for adjustment ofthe pH

or

acidity

of

the

wastewater,

removes

organic

oxygen

demanding

material

or

carbonaceous

biochemical oxygen demand (CBOD),

and

removes

solids,

as more fully

described

by

Mr.

Flippin.

The

effluent

discharge

meets

the

permitted

treatment

requirements and based on the data collected for monthly Discharge Monitoring Reports

(DMRs) by the Henry facility, the effluent quality is

summarized below:

1.

5-day

CBOD

or CBOD5

mass

loadings

average

less than

135

lbs/day,

which represents a treatment efficiency ofgreater than 96 percent removal

efficiency

through

the

treatment

facility

(secondary

treatment

is

considered

85 percent removal efficiency).

2.

The pH in

the Noveon effluent

normally

runs

around

7.2

standard units

(S.U.) ornear neutral pH.

3.

The Henry facility uses amines in the manufacture of its products.

These

amines are converted

to ammonia through a process known as hydrolysis

in

the

wastewater treatment facility.

Ammonia

measurements made

by

IEPA

and

by

Noveon

or

their

contractors

indicate

that

ammonia

concentrations in the effluent average around 900 pounds per day (lbs/day)

or 135 mg/L.

4.

The total dissolved solids (TDS) or salt content ofthe effluent ranges from

about 6,000 mg/L to greater than

10,000 mgIL.

The wastewater treatment

facility

does

not

remove

salt

nor

is

there

a

treatment

technology

economically feasible for salt removal.

The

City

of

Henry

P01W

also

discharges

through

the

Noveon

single-port

diffuser.

The total

flow from

the Henry

POTW

is

around

0.3

mgd

or 0.45

cfs.

The

POTW effluent is mixed

in the pipe with the Noveon effluent and the total flow of the

two discharges is around

1.1

mgd or

1.7 cfs.

2

---

River

Flow and Water, Quality Characteristics

The Illinois River flow varies based on the season with the lowest flows occurring

during summer and early fall months.

The IEPA regulations require that mixing zones be

established

fOr the 7-day

10-year low flow (7Q10) or the flow that has a

10 percent

()

chance ofoccurring in any given year.

Because statistically, flow varies by rainfall and

month

of the year,

the 7Q10

flows

for the

critical

months

of April

to

October were

determined

for

each month,

which

gives

a

statistically

equivalent 7Q10

flow

for the

individual month, as follows:

Summer Month

7Q10

April

6,900 cfs

May

5,500

cfs

June

5,900

cfs

July

4,400 cfs

August

3,700 cfs

September

2,900 cfs

October

4,300

cfs

These 7Q10 flows

calculated for each summer month to statistically determine the most

critical

low

flow were

determined

from

the

U.S.

Geological.

Survey

(USGS)

gage at

Henry for the years

1982 through 1993.

The Illinois State Water Survey has calculated a

7Q10 low flow of3,400 cfs based on data from all months ofthe year.

The average

yearly

flow in

the

Illinois

River

is

around

15,300

cfs,

with

the

monthly

average

flows ranging from a

low monthly average of around

8,800

cfs in

August to

a

high monthly average ofaround 26,400 cfs in March.

The water

quality

characteristics

of the

Illinois

River were

obtained

from

the

USEPA store

database for the Hennepin monitoring

site for the years

1977

to

1994

and

are described below.

1.

Background pH

in

the

River was

calculated as

7.7

S.U.

for the

critical

summerperiod.

2.

DO

concentrations in

the

River upstream from

the Henry

facility

are at

saturation during the

September critical period and DO

downstream from

the Noveon facility is around 94 to

96

of saturation.

The water quality

standard for DO

is

5

mg/L

or for a

September temperature of around 25

°C(77 to 78 °F),this represents about 61

ofsaturation.

3.

Background

ammonia

concentration

(NI-Li

+

NH3)

in

the

River

is

0.09

mg/L

during

the

summer

months

and

background

organic

nitrogen

is

around

1

mg/L.

4.

Background

TDS

in

the

River

during

the

summer

low

flow

period

is

around 350 to 500 mg/L.

Data

for

the

winter

indicate, that

these

months

are

not

limiting

periods

for

ammonia discharges.

3

---

4.

LOCATION OF DISCHARGE POINT AND PHYSICAL

CHARACTERISTICS

OF

THE

DISCHARGE

The Noveon single-port diffuser is located at about Illinois River mile (IRM)

198,

as shown

on Figure

1.

The discharge pipe is a single port placed along the bottom ofthe

river and discharging perpendicular to river flow.

The port is

18 inches in diameter.

The

discharge of the effluent,

although

initially

at a perpendicular

angle to

the River

flow,

rapidly reflects

in the ambient current to

a downstream direction,

as shown

in Figure 2.

Local water depths in the plume trajectory are about

13.5

ft.

The effluent exit velocity of

around

1

ft/sec

is

high when compared to the river velocity at low

flow of around

0.3

fl/sec.

The effluent is negatively buoyant, meaning it is denser than the river water, due

to

salt, but

the

effluent/river mixture

would be

approaching

neutral

buoyancy near the

downstream edge

of the

ZID.

A

single-port

diffuser

is

an

engineered

structure

that

provides rapid and immediate mixing.

5.

DEFINITION

OF

TERMS

Mixing

of

an

effluent

or

a

tributary

stream

‘entering

a

river

is

a

natural

phenomenon that allows the two waters to mix and reach equilibrium

where the

two

are

totally mixed.

The

mixing

of two

independent water

streams

into each

other can

be

physically described through very well-developed and recognized mathematical formulas

of dispersion.

Mixing zones

have

also

been included

in almost

all

states water quality

regulations

as

a

combination

of the

mathematical

descriptions

and

also

prescriptive

definitions that

minimize

the

areas of the mixing

zones

so as

not to

affect the

aquatic

resources or other uses ofthe river system.

Federal guidance

on mixing

zones has been

provided

by

the

U.S.

Environmental

Protection

Agency

(JSEPA)

in

the

document,

“Technical

Support Document for Water

Quality-based Toxics Control”

(TSD;

USEPA

March

1991)

and

by

the

Illinois

Environmental

Protection

Agency

(IEPA)

in

the

document,

“Illinois

Permitting

Guidance

for

Mixing

Zones”.

There

are

several

definitions and acronyms used to describe mixing zones in both guidance documents and

these are defined below.

Physical Descriptions ofMixing Zones

Physical mixing of a tributary or an

effluent discharge (the entering

stream) that

enters into a larger body ofwater (the receiving stream), such as the Illinois

River, occurs

because the entering stream ofwater normally has enough physical energy, either through

the entering velocity being greater than the receiving stream or there is a density gradient

between the entering

stream over that of the receiving stream.

This allows the entering

stream to

force

its way into the receiving

stream,

similar to

a

car entering the freeway

from a merging

lane.

The entering

stream will blend through natural

mixing processes

until

it is

in total

equilibrium

or totally mixed

with the

larger body of water

(i.e., the

entering

stream and

the receiving stream are at equilibrium concentration

and density).

Until the mixing

of the

entering

stream

and the receiving stream are in

equilibrium,

a

definitive

plume

where

the

entering

stream

and

the

receiving

stream

are

at

different

4

---

concentrations

and

densities

occurs.

This

plume

can

be

described

and

predicted

mathematically as discussed next.

The mixing zone for an entering stream, either an effluent discharge or a tributary,

is

divided

into a

near-field zone,

described as a

zone

of rapid and

immediate

mixing

caused by the energy of the entering

stream dispersing

into the receiving

stream, and

a

far-field

zone,

described as

mixing

by

the

natural

ambient diffusion

of the

receiving

stream slowly incorporating the plume into the whole body ofwater available.

The near-

field mixing zone occurs

quite rapidly, on the order of a few minutes or less, and the far-

field zone mixing

occurs much slower,

on the order of an hour or more.

The physical

mixing zones in a plume are depicted in Figure 3.

Near-Field Zone.

The near-field zone

is

defined as the turbulent

zone

at

the

discharge point where rapid and immediate mixing

occurs

due to the immediate mixing

of a high

energy stream with one of lower

energy.

Aquatic

life will not reside in this

zone

due

to

the

turbulence.

This

zone

consists

of

a

Jet

Momentum

Zone,

a

restratification zone (dependent on plume/river density differences afterthe-jet zone), and

a transition zone, the buoyant spreading zone, which

is a mixing

area where

the plume

goes

from

effluent-dominated

mixing

to

mixing

totally

dominated

by

river

ambient

diffusion

(natural energy and

dispersive,

spreading-out, forces

of the receiving stream).

When an entering stream, such as, an effluent discharge, flows into a

receiving stream, it

normally

has

an

excess

velocity

over

the receiving

stream

itself.

In the

case

of the

Noveon discharge, the port

exit velocity

is about

1

foot per second (ft/see) and

the river

velocity is about 0.3

ft/sec.

This excess velocity allows the effluent to push its way into

the river until

the river/effluent

mixture

reaches an

equilibrium velocity.

Additionally,

the Noveon discharge

is

heavier

than

the river

water and

this

density

difference

also

causes

the effluent plume

to have momentum or momentum generated by

gravitational

spreading.

The effluent/river

mixture in the near-field zone

is

dragged by the river in

a

downstream direction

and after a few minutes

of this rapid and

immediate mixing, the

plume

mixing

will

be dependent

entirely

on the river

ambient dispersive forces,

which

will

spread

the

plume

out

longitudinally,

or’ downstream

direction,

vertically,

or with

depth, and laterally, across the

river.

For the Noveon.discharge, the near-field zone is on

the order of about

100 ft before far-field mixing becomes dominant.

Far-Field

Mixing.

The far-field

zone consists

of the

buoyant spreading

zone

(actually a transition

zone between the near-field

and

far-field

zones)

and

the ambient

diffusion

zone, where

dispersion

is

totally

dependent

on a

much slower process called

ambient diffusion or spreading. out of the plume,

longitudinally, vertically

and laterally.

The river velocity is in a downstream direction, so the plume

spreads out most rapidly in

a

downstream

direction.

The

plume

mixes

vertically

according

to

density.

For the

Noveon discharge, the plume

is denser than the river (i.e., the plume wants to

sink or be

near the

bottom of the river, and

full vertical mixing

occurs

about

850

ft

downstream.

Because the longitudinal dispersion is the most rapid due to the velocity vectors being in

a downstream direction, the maximum concentrations or density in the plume

is

along the

centerline ofthe plume in a downstream direction.

For the Noveon discharge, the plume

5

---

spreads out in all directions, but the plume centerline

maximum concentrations are along

a narrow width in a downstream direction, on the orderofabout 150 ft wide.

Actual

Mixing

Zone.

The

actual

mixing

that

occurs

between

the

Noveon

discharge

and

the

River has

been physically

monitored

and

mathematically

modeled.

The mixing zone monitored in the Illinois River has been shown in Figure 2.

The near-

field mixing

including the jet

momentum zone through the early phases of the buoyant

spreading region is about

100 ft long

(see conductivity isopleth line of 2,000 micromhos

per

centimeter or umhos/cm,

which

is

equivalent to

approximately

1,280

mg/L of total

dissolved

solids

or

salt).

The dispersion

at the end

of this

near-field

mixing

zone is

around 20:1

or more.

The plume

is

vertically mixed from top to

bottom

at about

850 ft

downstream

and

the

plume

width

is

about

150

ft

wide

at this

point.

The

dispersion

achieved at the downstream edge of the plume at about

1,000 ft downstream is

100:1

or

more.

The

existing

single-port diffuser

is

effective in

dispersing

the effluent

into

the

Illinois River and the effluent has been and will continue to meet water quality and whole

effluent toxicity limits in this mixing zone.

Regulatory

Mixing Zone

Mixing

zones

have been allowed in the

U.S.

since the

late

1960’s and they

are

used to

provide protection to

the

receiving stream when treatment technology

or costs

prevent achievement ofthe numeric or whole effluent toxicity

standards in the discharge

itself.

The National

Academy of Sciences

in

1972

defmed mixing

zones

in

terms

of

limiting

the

exposure

time

and

concentration

to

1-hour

for

aquatic

species

passing

through

a

plume,

as

shown

in

Figure

4.

The

U.S.

Environmental

Protection

Agency

(USEPA) still uses this time concept in their guidance on mixing zones.

Several goals of

mixing zones are outlined in the USEPA Technical Support Document for Water Quality-

based Toxics Control (TSD, March 1991) and these goals are described below:

a.

Achieve maximum dispersion in the smallest area possible;

b.

Minimize the effects on the receiving water;

c.

Minimize acute and chronic toxicity in the receiving water;

d.

Meet narrative water quality standards within the defmed mixing zone;

e.

Provide maximum protection for the receiving water, even under upset or

abnormal events;

f.

Maintain a Zone ofPassage for fish;

g.

Meet the IEPA water quality regulations; and

h.

Meet the TSD Guidance on mixing zones.

In

order

to

achieve

these

goals,

IEPA

has

specified

in

their

Mixing

Zone

Permitting

Guidance

several

requirements

that

mirror

the

USEPA

TSD

guidance.

Specifically, IEPA allows the following:

1)

Zone of Free Passage, which establishes the maximum volume of

river

flow

that

can

be

used

for mixing

in

the Near-Field

Zone,

6

---

called the Zone ofInitial Dilution (ZID) and/or the Far-Field Zone,

called the

Total Mixing Zone (TMZ);

2)

Zone

of

Initial

Dilution

or

ZID,

establishes

a

regulatory

zone

where

acute numeric and whole effluent toxicity are allowed until

this initial rapid and immediate mixing is completed;

and

3)

Total

Mixing

Zone

or TMZ,

establishes

a

regulatory

zone where

chronic numeric

and whole

effluent toxicity are allowed for some

distance

downstream limited

by 26

acres and 25

of the volume

offlow or cross-sectional area.

Zone of Free

Passage.

IEPA has specified a Zone ofFree Passage for fish that

gives an upper bound for the volume ofriver flow that can be used to disperse an

effluent

in the river.

The IEPA guidance states:

“The 25

of cross-sectional area or volume offlow establishes the extent of the

Zone ofPassage given at 35

Ill.

Adm.

Code

302.102(b) (6) for mixing

situations

where the upstream flowto effluent dilution ratio is

3:1

or greater.”

IEPA has also specified a maximum area for a mixing zone of26 acres that would

be

bounded by

a width determined from this

Zone of Free Passage requirement.

A total

length of the mixing

zone

can

then be

calculated from

the

25

of volume

or cross-

sectional area restriction and the 26-acres restriction.

IEPA has permitted both a Zone of

Initial Dilution

(ZID) and Total Mixing Zones (TMZ) based on the ZID volume offlow

allowed.

Mixing zones rarely require the full 26 acres to achieve water quality

standards

and Noveon has asked for less than

5

acres for the TMZ.

Zone ofInitial Dilution (ZID).

The ZID or Zone ofInitial Dilution is defined as

the zone of immediate and rapid

mixing,

as

depicted previously in

Figure

3.

The ZID

was conceptually

introduced by the National Academy of Sciences in

1972, as shown in

Figure 4.

USEPA lists in the TSD several criteria for defining a ZID:

1.

Use a high-velocity diffuser with port

exit velocities greater than or equal

to

10

ft/sec to

limit exposure to oniy a few minutes (i.e.,

3 minutes).

For

multiport

diffusers,

the

TSD

specifies,

“...hydraulic

investigations

and

calculations

indicate

that

the

use

of a

high-velocity

discharge

with

an

initial

velocity

of 3

meters per

second, or more, together with

a mixing

zone

spatial

limitation

of

50

times

the

discharge

length

scale

in

any

direction, should ensure that the CMC (Criterion Maximum Concentration

or acute toxicity limit) is met within a few minutes under all conditions”.

IEPA does not use the fundamental time

limitation, but

does refer to

the

spatial

limitation of 50

*

the

discharge

length

scale or in

the

case of a

diffuser,

50

*

square root ofthe cross-sectional area of a single port.

The

time

is

the

fumiamental

basis

for

USEPA’s

definition

of a

ZID,

although

IEPA does not

use this

as a

basis

for the ZID.

The discharge

length scale criterion is not a fixed length, but rather a requirement to meet

7

---

a minimum time and the discharge

length

scale is

a way to

estimate that

this

minimum time

is

met

for almost

all

discharges.

The

50

times

the

cross-sectional

area of a single port

approximates the

distance known as

the

Zone

of Flow Establishment, as

shown

in

Figure

5,

and

is

a

zone

where effluent momentum dominates the dispersion.

This is only a small

part of the

physical

hydraulic

zone

of rapid and

immediate

mixing,

as

presented

in

Figure

6.

The

actual

jet

momentum

zone

extends

to

approximately

just

beyond

where

the

edge

of the

plume

reaches

the

surface, as depicted in Figure

7.

The rule ofthumb for the Jet Momentum

Zone

downstream from

a diffuser

is

on the

order of one

diffuser

length

(i.e.,

0.5

to

1.5

*

diffuser

length).

This

distance

is

dependent

on

river

velocity and the jet

momentum

shrinks at

low

river velocities or flows,

and elongates at high river velocities or flows.

2.

For

other

discharges

that

don’t

meet

the

10

fl/sec

port

exit

velocity

criterion,

e.g.,

but

still

achieve rapid

and

immediate mixing, the USEPA

and IEPA use three methodsto determine the ZID which are:

a.

50 times

the square

root of the

cross-sectional area of the

port

(port diameter is

1.5 feet)

=

66.5

ft ZID length for the

Noveon single-port diffuser;

b.

5

times the local water depth (depth

=

13.5

ft)

=

67.5

ft; and

c.

10

of the

total

mixing

zone

(allowable

mixing

zone

length defined by

26 acres divided by width of25

ofthe

cross-sectional area or about

250 ft for the Illinois River at

Noveon)

-~

4,530

ft; Noveon requested 1,000 ft total mixing

zone.

Under this total

mixing

zone TMZ length,

the ZID

would be 10

ofthe

1,000 ft or 100 ft in length

From

these

three

scenarios,

a

ZID

distance

of

66

ft

was

determined

and,

a

dispersion

of

13.2:1

was

determined

for

the

single-port

diffuser

during

the

summer

(limiting

condition).

With

both,the

Noveon and

Henry P01W

discharging through

the

single-port diffuser and using the background temperature, pH and total

ammonia values

from the upstream monitoring

station, a total

ammonia concentration of

155

mg/L

could

be

discharged from

the Noveon single-port

diffuser and

meet

the

IEPA water quality

standards at the downstream edge ofthe ZID (point ofmaximum concentrations).

It

is

important

to

note

that,

in

each of these

ZID

length

determinations,

the

USEPA

and,

therefore,

IEPA

specify that

these

lengths are

to

be

met

in

“any

spatial

direction”.

USEPA defines spatial

as a

discharge length

scale

or distance

is defined in

each ofthese cases as a length along the centerline ofthe plume.

In free-flowing streams,

such as, the

Illinois

River (versus tidal

two-dimensional flow situations),

this

length

is

defined

in

the downstream

flow direction or along

the length

where

maximum

plume

concentrations

occur.

The

25

of cross-sectional area or volume of flow

specifies a

method to define the maximum volume ofwater available for mixing, either in the ZID or

in

the

TMZ

and

is

used as

one

dimension

in

defining the

total

allowable length of the

8

---

mixing

zone or 26

acres divided

by a width

equivalent to the

25

of volume

or cross-

sectional area in order to give a total

length allowable.

The

intent ofthe mixing

zone is

to achieve maximum dispersion in the smallest area possible

and therefore

dispersion in

the ZID should be maximized.

IEPA has specified for other discharges with permitted mixing zones that

spatial

direction

in

mixing

zones

downstream

from

high-rate

multiport

diffusers

is

in

the

direction of flow, e.g.,

American

Bottoms Regional

Wastewater Treatment

Faciltiy

in

Sauget, Illinois; Olin Chemical in East Alton, Illinois; 3M in Cordova,

Illinois; and Rock

River Water Reclamation District in Rockford, Illinois and has used the actual hydraulic

mixing zone to establish the dispersion in the ZID.

In keeping with the original concept of mixing zones, USEPA

also states “that a

drifting

organism would

not be exposed to

1-hour average concentrations exceeding the

CMC”.

The

CMC

is

the Criterion

Maximum

Concentration

or the

concentration

that

would

cause

acute

toxicity.

In reality, drifting

organisms

would

be

swept downstream

within a few minutes of entering the ZID downstream from the Noveon diffuser.

Total MixingZone

(TMZ).

The TMZ is the zone that is

bounded by a width of

25 percent ofthe cross-sectional areaor volume of flow in the River and a total area of26

acres.

The numeric water quality criteria and whole effluent-chronic toxicity must be met

at the downstream edge ofthis mixing

zone.

The maximum concentrations in a mixing

zone are along the centerline ofthe plume, as shown in Figure

8 and all mixing

zones, as

well as, ZIDs are based on meeting the standards for the maximum concentrations along

the centerline ofthe plume.

The length ofthis zone is not defined by

USEPA other than

in

original

mixing

zone documents as

a time

constraint of

1

hr of total

exposure for a

mobile aquatic organism,

as previously shown in Figure 4.

IEPA defines the

TMZ

as a

total

area of 26

acres, which

would

be

bound

by

a

defined width of 25

percent

of the

cross-sectional area (width times depth).

Since the Illinois

River at the site is

850

ft wide

at low flow,’ the

width can be

conservatively defined as at least 250

ft,

as presented in

Figure 9, and the length can be calculated as follows:

(26 acres)(43,560 sq ft/ac)/250 ft

=

4,530 ft

Noveon

has defined the TMZ

in their joint mixing

zone

with

the POTW discharge as

having a length of 1,000 ft giving a total area ofabout

5

acres or less than one-fifth ofthe

total area actually allowed under the Illinois mixing zone guidance.

Enhancements to Dispersion

There are several engineering

designs that can enhance the mixing of an effluent

into

a

receiving

stream,

such

as

the

Illinois

River.

The

most

common

engineered

structures

being

used today

are

either

a

single-port

diffuser

placed

near

the

channel

bottom or a multiport diffuser placed nearthe channel bottom.

9

---

Single-Port Diffuser.

A

single-port diffuser is

a single pipe located on or near

the bottom ofthe river that

disperses the effluent rapidly and

immediately

into the river.

Single-port

diffusers achieve a greater

dispersion than the original

side-channel

surface

discharges that

were

common

prior

to

the

1980’s to

1990’s and

dispersion of

10:1

or

more can be achieved within a short distance downstream from these types ofdiffusers.

In the case ofthe Noveon single-port diffuser, a dispersion of 13:2:1

is

achieved within a

short

distance

downstream from the

discharge.

The existing

single-port diffuser meets

chronic

numeric

criteria and

chronic whole

effluent

toxicity

at

the

typical

discharge

conditions ,at about 500 to 1,000 ft from the diffuser, depending on flow.

Multiport Diffuser.

A

multiport diffuser is a pipe with multiple discharge ports

that would

discharge the effluent

so that

the

effluent

exit velocity

from

each port

is

at

least

10

ft/sec

in

order to

achieve

rapid

and

immediate

mixing.

A

multiport diffuser

spreads the effluent out over the length ofthe diffuser and

achieves greater dispersion by

supplying

greater energy

(10

ftlsec

exit

velocity)

for jet momentum

into

the receiving

stream at each ofthe individual ports.

Multiport diffusers have been installed for effluent

discharges

since

about the

late

1980’s and

this

type

of

diffuser

is

currently

the

best

technology

for

ensuring

stream

water

quality

standards

are

met

under

almost

all

conditions.

A

multiport

diffuser,

as

depicted

in

Figure

10,

has

been

conceptually

designed for the Noveon discharge to replace the existing

single-port diffuser.

Both the

ZID and the TMZ distances are physically dictated by the ambient velocity in the River

or flow with the plume elongated at high flows (pushed further downstream) and mixing

closer to

the diffuser at low flows (diffuser discharge energy causes plume to

mix more

quickly

in

lower

ambient currents).

The

dispersion

that

will

be

achieved

from this

diffuser at the edge of the

ZID has been projected at 43:1

at a downstream distance

of

less than

50

ft (on the order of 15 ft downstream).

All acute numeric criteria and

acute

whole

effluent toxicity will be

met

at the edge ofthe ZID.

The multiport diffuser will

meet chronic numeric criteria and chronic whole effluent toxicity within about 100 to 250

ft from the diffuser.

The projected plume from the diffuser is presented in Figure 11.

6.

REGULATORY AND HYDRAULIC

ZIDs AND TOTAL

MIXING ZONES

Regulatory

ZIDs

have

been

defined

to

minimize

the

time

of

exposure

for

organisms passing

through

the mixing

zone to

acutely toxic constituents,

e.g.,

salt.

To

ensure that this time is minimized to just a few minutes,

the regulators have used partial

ZID hydraulic descriptions to give minimum guidance lengths for a ZID.

USEPA defines

the hydraulic definition ofthe mixing zone as two zones:

1.

Mixing

and

dilution

in

the

first

stage

are

determined

by

the

initial

momentum and the buoyancy ofthe discharge, which is

the actual ZID or

near-field mixing zone.

2.

The second

stage of mixing

covers

a

more extensive

area

in

which

the

effect of initial

momentum and

buoyancy

is

diminished

and the waste

is

mixed primarily by ambient turbulence.

10

---

Both ofthese zones are influenced by the effluent discharge itself, as well as, the

flow in the river.

The first stage ofhydraulic mixing, which is

dominated by

the energy

ofthe effluent discharge itself,

is normally hydraulically described as the jet momentum

zone, where

the plume

expands to

mix with

the total

amount of ambient water passing

over the port.

This jet zone normally

is

mathematically projected until

the

edge

ofthe

plume interacts with the

surface,

as depicted previously in

Figure

7.

At this point, the

plume

has

reached

the

surface

and

physically

one

can

sometimes

see

a

boiling

or

turbulence at the surface where this occurs.

At this point, the plume will undergo further

buoyant spreading due to any density difference between the plume and the ambient river

water.

The buoyant

spreading zone

is

a

gravitational

spreading region

where density

differences provide a momentum driver.

Different hydraulic

mixing zone models,

(e.g.

UDHKDEN,

CORMIX),

approved

by

the

USEPA,

use

the

point

or

a

short

distance

downstream from this point in estimating the ZID.

The second stage is dominated totally by the ambient diffusion ofthe river and is

hydraulically described as the far-field mixing zone.

The buoyant spreading region is for

the mostp~a transition zone between the near-field and the far-field zones and is often

divided to be

a part ofboth zones.

The effluent plume will eventuallymix in the ambient

currents

until it is

completely mixed in the

total

river flow.

Mathematically, we divide

the river up into boxes with equal widths

and transfer or mix the plume to the closest box

out from the plume and then to the next box, etc.

This transfer across the whole width of

the river takes

a

considerable distance

or time,

since

swimming against

the current

is

harder than swimming downstream with

the current.

This will not

normally

occur in a

River such as the Illinois

River until

several miles

(on the order of

10

or more miles)

downstream from the discharge.

IEPA, as well as most other states, limit the volume of

flow or cross-sectional area for mixing

zones to

about

25

of the flow and IEPA also

limits the total length by setting a maximum area forthe mixing zone of 16 acres.

7.

WATER

QUALITY EFFECTS

Toxicity

Both

ammonia and

salt

have been

identified

from

laboratory

bioassay

tests

on

fathead minnows and water fleas as causing acute

toxicity in the Noveon effluent.

It

is

noted that this is based on laboratory

toxicity tests and

it is important to note that given

the rapid mixing

of the Noveon

discharge, there

are no

impacts

on

aquatic

life in

the

Riverresulting from

the Noveon discharge.

With the mixing zone downstream from the

existing

single-port

diffuser

and

the

projected

mixing

zone

downstream

from

the

multiport diffuser, the identified toxicity

in the EA Engineering toxicity report would not

impair water quality in the River.

Ammonia or NH3.

Ammonia exists in the environment both as the ionized form,

NH4,

which

is

not

toxic,

or as the

unionized

form,

NH3,

which

can be

toxic

to

both

fathead minnows

and water fleas in laboratory tests.

Ammonia is converted

to more of

the unionized

NH3

as pH

reaches

8

standard units

(S.U.)

and

above.

The pH of the

effluent

is

near a neutral pH of 7,

but the Illinois River has a pH

of around 7.8

during

11

---

critical

periods.

With

the

current

single-port diffuser

and

the

combined

discharge of

Noveon

and

the

Henry POTW,

the

Noveon effluent

ammonia

concentrations

can

be

around

155

mg/L

and meet the ammonia acute water quality standard at the edge ofthe

ZID, as defmed by the IEPA ZID limitation of50

*

square root ofthe cross-sectional area

ofthe port.

Because the effluent ammonia was measured one time at around 200 mg/L, a

multiport diffuser that would

give a dispersion of around 43:1

at the downstream edge of

the ZID has been designed and has been proposed for installation in place of the current

single-port diffuser.

The diffuser would provide maximum protection to the River in the

shortest distance and smallest area.

The diffuser design is presented in Figure

10.

There

has been

no water quality or toxicity problems observed

in the vicinity

of the Noveon

diffuser and the existing physical mixing zone has been effective.

Salts.

Ammonia has been consistently

listed by IEPA as the primary toxicant in

the effluent,

but

salt has

most

likely been

a

more consistent

or at least as consistent

constituent

in

the

effluent

that

causes

laboratory

toxicity

in

effluent

samples.Total

dissolved

solids

consisting primarily

as

sodium

chloride

or NaCl

(commonly

used

as

table salt) is also toxic to fathead minnows

and water fleas.

A dispersion of around 7

to

9:1

is required to prevent effluent toxicity at the downstream edge ofthe ZID.

IEPA had

recommended

a

ZID

that

would

only

give

a

dispersion

of

around

6:1.

This

ZID

dispersion would

not be protective of acutely toxic conditions at the downstream edge of

the ZID, even if no ammonia were in the effluent.

Dissolved Oxygen

AquAeTer

developed

a wasteload

allocation model

using

the USEPA

QUAL2E

model,

data

from

the

Illinois

River,

and

reaeration

rates

and

deoxygenation

rates

measured

on

similar

size

rivers.

It

was

found,

that

during

critical

7QlO

and

corresponding high-temperature periods, that the DO

concentration

in the Illinois River

downstream

from

the Noveon discharge

is

around

7.5

mgfL,

as compared

to

the DO

standard of

5

mgfL for this time period.

The model was run with the Noveon discharge

with permitted 5-day

carbonaceous

biochemical oxygen

demands

(CBOD5)

or organic

loadings and

high

ammonia loadings.

Both of these demand oxygen

from the

river as

they

further

naturally

decay

in

the

river through

natural

uptake

by

resident

bacterial

populations

in

the River.

When the model

was run to

simulate no

discharge from

the

Noveon plant, the DO was increased slightly in the downstream reaches by less than 0.2

mg/L.

The accuracy ofthe DO measurement is

+/-

0.1

mg/L,

so the actual impact to the

DO in the River can probably not be measured for all practical purposes.

The river meets

DO

standards

based

on

the

available

data

for downstream

locations.

Therefore,

the

Noveon discharge is not impacting DO in the River and

DO standards

are met.

8.

Allowable Discharge of Ammonia

As

part

of the

relief requested

in

these proceedings,

Noveon has

requested

to

install

a high-rate

multiport diffuser in place

of their current

single-port diffuser.

This

12

---

multiport diffuser has

been designed

to

achieve

a

dispersion

of 43:1

and

an

effluent

ammonia concentration greater than 220 mg/L

could be

discharged and still

meet IEPA

ammonia water quality

standards at the edge of the ZID.

The diffuser would

allow the

ZID and

TMZ

to

be

met

in the smallest

area possible

and

would

be

protective of the

aquatic environment for both ammonia and salt that

is contained in the effluent.

Effect, if any, on Water

Quality

NH3 WQ Standards.

There has been no observed effect to aquatic species in the Illinois

River or to

water quality standards in the River based on the current discharge.

With the

new multiport diffuser,

water quality

standards

for NH3

will be met

for both

acute and

chronic water quality

standards within about

100 to 250 ft from the diffuser.

Acute and

chronic toxicity for both NH3

and salt will also be met within this distance.

The diffuser

will provide the maximum protection forthe aquatic environment in the Illinois River.

Dissolved Oxygen.

DO is

being met in the Illinois River downstream from the Noveon

plant with DO being between 94 and 96

of saturation on average during the critical

month of September.

A waterquality model has been runwith the maximum

concentrations ofCBOD and

ammonia from Noveon input into the model.

The discharge

from Noveon has projected to result in less than 0.2 mg/L oxygen change from a no

Noveon discharge scenario.

This DO change is less than the accuracy ofthe DO test of

+/-

0.1

mg/L and would be immeasurable in the River.

DO in the River at maximum

CBOO and ammonia loadings has been projected to be around

7.5

mg/L during critical

warm-weather low-flow conditions, as compared to a DO

standard of

5

mg/L.

This is not

unexpected since the low flow in the River of 2,900 cfs in September is still greater than

2,300 times the Noveon effluent flow of 1.23

cfs or the Noveon effluent only represents

about 0.04 percent ofthe flow in the River.

13