U.S.  Environmental  Protection Agency
Office of Wastewater Enforcement and Compliance
              Washington, D.C.
        Evaluation of Oxidation Ditches
             for Nutrient Removal
                September,  1992

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                                    NOTICE
Mention of trade names or commercial products does not constitute an endorsement by
EPA.  Omission of certain products from this document does not reflect a position of
EPA regarding product effectiveness or applicability.

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                                    CONTENTS

Section
OXIDATION DITCH FACT SHEET
                                                                             Page
FIGURES . ........................................                              ,M .-
                                                .......................       J-J-x

TABLES ............................................... . .................        iv

EXECUTIVE SUMMARY  . . ..................................................         ^
         BACKGROUND AND OBJECTIVES .......................... ..........         1
         FINDINGS AND CONCLUSIONS. . .................... '.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.         2
.
   1     THEORY OF NITRIFICATION, DENITRIFICATION AND
           PHOSPHORUS REMOVAL ..........................................      1_ i
              NITRIFICATION ................................. '.'.'.'.'.'.'.'."'      I- 1
              DENITRIFICATION .................................. '.'.'.'.'.'.'.'.      1- 2
              PHOSPHORUS REMOVAL .......................... '...'.'.'.'.'.'.'.'.'.'.      1- 3

   2     DESCRIPTION OF THE OXIDATION DITCH ............................      2- 1
              INTRODUCTION ........................ . ........ '.'.'.'.'.'.'.'.'.'.'.'.      2- 1
              DESIGN VARIATIONS .......................... '.'.'.'.'.I'.'.'.'.'.'.'.'.      2- 3
                   Eimco ......... .... .................. ..............         2 - 3
                   Envirex .............................................      2- 7
                   Innova-Tech ..................... ....................      2-10
                   Lakeside ............................................      2-12

   3     PERFORMANCE DATA ...............................                      3. l
              INTRODUCTION. ... ................... ...... ................      3. 1
              SITE OBSERVATIONS .................... '.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.      3- 6
                   Thurmont,  Maryland ..................................      3. 7
                   Fredrick,  Maryland ..................................      3_10
                   Patuxent Water Reclamation Facility,
                     Crofton, Maryland .................................      3.^4
              OTHER PLANTS PROVIDING DATA ........................ ......      3-15
                   Cedarburg, Wisconsin ................................      3-15
                   Dousman, Wisconsin ..................................       3-17
                   Dupage County,  Illinois .............................       3_18
                   Hanover , Pennsylvania ...............................       3-19
                   Huntsville,  Texas -  Parker Creek Plant ..............       3-20
                   Huntsville,  Texas -  South  Plant .....................       3-21
                   Kemmerer, Wyoming ...................................       3-22
                   Lake  Geneva, Wisconsin ..............................       3-22
                   Lyons,  Wisconsin .............................. .......       3-23
                   Morgan City, Louisiana .................. . ...........       3-24
                   Mount Clemens , Michigan .............................       3.25
                   Rehoboth Beach, Delaware ............................       3-25
                   Wanaque , New Jersey .................................       3-26
                   Gwinnette County,  Georgia ............... . ...........       3-27

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                                    CONTENTS
Section

   4
OXIDATION DITCH COSTS	
     CAPITAL COSTS	
     OPERATION AND MAINTENANCE COSTS.
         REFERENCES.

         APPENDIX A
         Monthly Average Tables and Chronological Plots for Wastewater
         Treatment Plants Providing Data

         Gedarburg,  WI
         Dousman, WI
         DuPage County,  IL (Knollwood Plant)
         Hanover, PA
         Huntsville, TX (Parker Creek and South Plant)
         Kemmerer, WY
         Lake Geneva,  WI
         Lyons, WI
         Morgan City,  LA
         Mt.  Clemens,  MI
         Rehoboth Beach,  DE
         Wanaque, NJ
         Yellow River/Sweetwater Creek Water Reclamation Facility,
           Gwinnette County,  GA
4- 1
4- 1
4- 3

5- 1
                                      ii

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                                       FIGURES
  Figure                                                                       page

* FS-1     FLOW DIAGRAM	      FS-4

  FS-2     CONSTRUCTION AND OPERATING COSTS AND ELECTRICAL ENERGY	      FS-6

    1A  .   TYPICAL CHANNEL CONFIGURATIONS FOR SINGLE CHANNEL
           OXIDATION DITCH	      2- 2

    IB     TYPICAL SCHEMATIC OF A MULTIPLE CONCENTRIC CHANNEL
           OXIDATION DITCH	      2- 2

     2     BASIC CARROUSEL SYSTEM AND MODIFICATIONS FOR NUTRIENT REMOVAL       2-5

     3     TYPICAL THREE CHANNEL ORBAL OXIDATION DITCH AND MODIFICATION
           FOR NUTRIENT REMOVAL	      2- 8

     4     TYPICAL BARRIER OXIDATION DITCH AND DRAFT TUBE	      2-11

     5     TYPICAL LAKESIDE OXIDATION DITCH AND MODIFICATION FOR
           NUTRIENT REMOVAL		      2-14

     6     CHRONOLOGICAL PLOTS OF MONTHLY AVERAGE DATA -
           THURMONT,  MARYLAND - JANUARY THROUGH JULY 1991	      3-9

     7     CHRONOLOGICAL PLOTS OF MONTHLY AVERAGE DATA -
           FREDERICK, MARYLAND - JANUARY 1990 THROUGH JULY 1991	      3-12

     8     CHRONOLOGICAL PLOTS OF MONTHLY AVERAGE DATA -
           FREDERICK, MARYLAND - JANUARY 1990 THROUGH JULY 1991	      3-13

     9     CHRONOLOGICAL PLOTS OF MONTHLY AVERAGE DATA - PATUXENT WATER
           RECLAMATION FACILITY,  CROFTON, MARYLAND - JULY 1990 THROUGH
           JULY 1991	      3_16

    10     CAPITAL COSTS.	      4. 2

    11     OPERATING  AND  UTILITY COSTS	      4. 5
                                        ill

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Table




   1




   2 .




   3




   4




   5




   6
                            TABLES






OXIDATION DITCH SUPPLIERS CONTACTED	




PERMIT LIMITS FOR PLANTS THAT PROVIDED DATA.




DESIGN BASIS FOR OXIDATION DITCH PLANTS	




PERFORMANCE DATA	




CAPITAL COSTS	




OPERATING COSTS	
Page




2- 4




3- 2




3- 4




3- 5




4- 1




4- 4

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                               EXECUTIVE SUMMARY

BACKGROUND AND OBJECTIVES

    The U.S. Environmental Protection Agency (EPA)  has encouraged the evolution
of better and more  efficient  wastewater treatment  techniques by  supporting  the
application  of new technologies.   The  Office of  Wastewater  Enforcement  and
Compliance  (OWEC)  evaluates  specific technologies  to determine  performance
capabilities  and  the ability of the technology to  meet specific  treatment
needs.  This report focuses on the use of oxidation  ditches for  nitrification,
denitrification and phosphorus removal.

    The  oxidation ditch is  an extended  aeration,  continuous  flow,  activated
sludge treatment process.  Oxidation ditches were  first used in the  1950s as an
easily operated and low  cost  method  to treat wastewater in small towns in  the
Netherlands.  Oxidation  ditches were  first  installed  in the  United  States in
the early 1960s.(1)   Since then, the number  of oxidation ditches has  increased
to 550 in 1975 and to more than 1800  in 1991.

    Oxidation  ditches  were  usually not  designed  for nitrification  or
denitrification.   Design  parameters  used,  however, often  ensured  that
nitrification occurred.   Current concern  over nutrient discharges  to natural
water systems has  led to interest in upgrading existing oxidation ditches  and
modifying the oxidation ditch  system design  to incorporate biological nutrient
removal.

    The objective  of this study was  to identify  oxidation ditch plants that
were achieving  nutrient  removal,  and  to  obtain typical design parameters  and
costs.   To  accomplish this,  oxidation ditch manufacturers were contacted to
identify plants designed for nutrient removal.   In addition,  other  oxidation
ditch plants were contacted to  obtain  information on performance of plants  not
specifically designed for nutrient removal.  References describing this process
and providing operational data were also utilized as  informational sources.

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                                                                          Page 2

     This  report  reviews  the  theory of  nitrification,  denitrification  and
 biological  phosphorus  removal  and describes  the design and  operation  of
 oxidation  ditchesfor  nutrient removal.   Performance  data on nutrient  removal
 from plants  contacted are presented  and discussed.  Capital  cost  data obtained
 are presented and analyzed with plant design flows.  Operation and  maintenance
 costs were  also obtained.   The results  of  the study were  summarized  in  EPA
 format "Fact Sheet."   The following  presents  the  Findings and Conclusions  of
 the study and the fact sheet.

 FINDINGS AND CONCLUSIONS

     Oxidation ditches  are typically designed with a nominal hydraulic detention
 time of greater than 10  hours  at average design flows.  At typical mixed liquor
 solids  levels,  mean cell  residence time  is  adequate  for nitrification,
 especially in warm weather, if enough oxygen is supplied.

     Data  were collected  from  17 oxidation ditch municipal wastewater treatment
 plants  in the United States.    The  average  design flow  for these  plants  ranged
 from 0.1  to  12.0 mgd.  Design hydraulic detention times at average design flows
 ranged  from 10  to 34 hours.    Design  mean  cell  residence  time (sludge age)  was
 available  for 8 of the plants  and  ranged  from  12 to 48 days.  Design organic
 loadings  of 13  oxidation ditches,  where the information was  available,  ranged
 from 5.8 to  39.2 Ibs BOD/day/1000 cubic feet.

    Twelve  of the plants  contacted were designed  for  nitrification and five
plants were  designed for  denitrification.   Two  of the plants  were  designed  for
biological phosphorus removal.

    The average  flow at  the  17 plants ranged  from 30 to  116  percent  of  the
design  flow.   The average  effluent  BOD  ranged  from 1.9  to 10.5 mg/1  and
removals ranged  from  90  to 99  percent.   All but one  plant measured effluent
ammonia nitrogen (NH3-N).   Influent  NH3-N  was  measured at 14  of the plants.

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                                                                            Page  3

*  The  average  influent  ammonia  concentration, during  all  seasons where  data were
   available,  ranged from 12.0  to  23.5 mg/1.    The average effluent  NH3-N
  concentration ranged from  0.05 to  2.7 mg/1.   The average  removal  of  NH3-N
   ranged from  86 to 99 percent.

        Four plants  measured  influent and  effluent  TKN  and nitrate  (N03-N)
   concentrations.   Of these four plants, two were  designed for denitrification.
   The  removal  of total nitrogen was  87 percent at  one  plant.   At the  second
   plant,  operated  for denitrification during  the summer,  the total nitrogen
   removal was  88 percent.

        Influent and  effluent phosphorus were  measured at six plants  and effluent
   phosphorus was measured at one plant.  Five of the plants were not designed for
   biological phosphorus removal and chemicals were added.   At one plant, designed
   for  biological phosphorus removal,  the average  influent phosphorus was  reduced
   from 2.5 mg/1 in the  influent to 0.55 mg/1  in the effluent.   At the other plant
   designed  for enhanced biological phosphorus  removal,  chemicals  were added to
   meet the permit limit of 1 mg/1.

        The  oxidation ditch  performance  data showed that nitrification occurred in
   typical  oxidation ditch designs.   Most of the  NH3-N data collected were from
   the  summer months, during which time permit limits were  generally met.   Limited
   data showed  that  nitrification  also  occurred  during  winter months.  An  average
   total nitrogen  removal of 88 percent  was  achieved in the two plants designed
   for  denitrification when operated in this mode.

        Modifications to  the basic oxidation  ditch design  can be made to  achieve
   nitrogen and phosphorus  removal.  The  key  to  obtaining  nitrogen  removal is the
   proper  control  of  dissolved  oxygen levels  in  different sections  of  the
   oxidation ditch, and  the maintenance of adequate mass of bacteria under  aerobic
9,
   and  anoxic conditions.  To meet more stringent total nitrogen effluent limits  a
   separate anoxic  channel or  basin  outside the ditch  channels  may be  added.

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                                                                         Page 4

Holding mixed  liquor under anaerobic  conditions  is  required  for enhanced
biological phosphorus  removal.   This can  be accomplished  in  either a  non-
aerated channel or by adding  an anaerobic basin before  the  aerobic oxidation
ditch channel.

    The  total capital costs, based on the information received from 10 plants
averaged $4.89/gpd design capacity.   The capital costs  ranged  from $1.61  to
$9.99/gpd.   These costs  were  for the entire  plant  and  included  engineering,
construction supervision and contingencies but did not include land costs.

    Overall operating costs ranged from $0.08 to $1.00/gpd based on the average
flow of  eight plants  for which  data were  available.  Utility  costs  ranged  from
$0.04 to $0.16/gpd based on the average  flow  for seven plants for  which  data
were available.

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                                                                       Page FS-1
                           OXIDATION DITCH FACT SHEET

 Description - An  oxidation ditch  is  an activated sludge biological  treatment
 process;  commonly operated in the extended aeration  mode.   Typical  oxidation
 ditch treatment systems consist  of single channel or concentric, multichannel
 configurations.

 Some form of  preliminary  treatment such as bar  screens,  comminutors, or grit
 removal normally precede  the oxidation  ditch.   Primary settling prior  to an
 oxidation ditch  is sometimes practiced,  however it is not common.  Flow to the
 oxidation ditch is  mixed  with  return  sludge  from a secondary  clarifier and
 aerated.   The aerators  may be brush  rotors,  disc aerators,  surface aerators,
 draft tube aerators,  or  fine bubble diffusers.  The aerators provide mixing and
 circulation in  the  ditch,  as  well  as oxygen  transfer.    A high  degree  of
 nitrification  occurs in the ditch due  to  operation in the  extended aeration
 mode.  Oxidation ditches are  typically  designed with  a nominal  hydraulic
 detention time at  average  design flow of greater  than 10 hours and a mean cell
 residence time  (sludge age) ranging from 10 to 50 days.    Oxidation  ditch
 effluent  is usually settled in  a  separate secondary  clarifier,  however,
 intrachannel clarifiers are  also used.

 Common Modifications  -  Ditches  may be  constructed of  various materials,
 including  concrete,  gunite,  asphalt,  or  impervious membranes.   Concrete  is the
 most  commonly  used.   The  single channel  oxidation  ditch  may be  found  in  a
 variety of shapes including ovals, horseshoes,  or  ells, whichever  best fits the
 site.   The concentric multichannel ditches may be circular or oval  in  shape.
 The  addition of  an intrachannel  clarifier  may be incorporated into  the  ditch
 design.

An  oxidation  ditch  may be  operated  with  an  anoxic  zone  in  the  channel to
 achieve partial denitrification.   An anoxic tank  upstream of the ditch may be
 added along  with recycle to  that tank from the anoxic zone in the channel to
 achieve higher levels of denitrification.  A anaerobic tank may be added prior
 to the ditch for enhanced biological phosphorus removal.

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                                                                      Page FS-2

 Technology Status  r  There  are  over  1800 municipal oxidation ditch installations
 in the United States.   The overall  process is fully demonstrated as a secondary
 treatment process.   Nitrification has been shown to  occur when  ditches  are
 operated in the  extended aeration mode .

 Typical Equipment/No,  of Manufacturers - Oxidation ditch equipment (aerators)/6
 major suppliers

 Applications - Oxidation ditch technology is applicable in any situation where
 activated sludge treatment (conventional or extended aeration) is appropriate.

 Limitations  - Oxidation  ditches   offer  an added measure of reliability  and
 performance over other biological processes but are subject to some of the same
 limitations that other activated sludge treatment processes face.

 Performance  -  The  average performance of  16  oxidation  ditch  plants  is
 summarized below:
                          Effluent (rng/1)
Percent Removal
BOD
Suspended Solids
Winter
5.5
6.5
0.88
Summer
4.4
5.3
0.45
Annual Avg
4.9
5.9
0.68
Winter
98
96
95
Summer
98
98
97
Annual Avg
98
97
96
Note: Winter November through April, Summer May through October
Chemicals  Required - None;  metal  salts can be  added for enhanced  phosphorus
removal .
Residuals  Generated - Primary  sludge  if primary clarifiers precede  oxidation
ditch.  Secondary  sludge  is  generated  at quantities  similar  to other activated
sludge processes .
Design Criteria - (Extended Aeration Mode)
BOD Loading - 5 to 20 lbs/1,000 ft3 of aerated volume/day
Sludge Age - 10 to 50 days
Oxidation Ditch Hydraulic Detention Time - 10 to 35 hours

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                                                                       Page  FS-3


Unit  Process Reliability -  The  following table indicates  the percent of  time
the  monthly average  effluent concentration of  the given  pollutants  was  less
than  the concentration  given in the first  column.   This  table was  developed
from  data for  16 oxidation ditch plants.
           Percent of time Effluent concentration in mg/1 Less than

Concentration      Suspended Solids     	BOD
    (mg/1)         Winter     Summer

     0.2             0          0
     0.5             0          0
     1.0             2          1
     2.0             7         13
     5.0            49         67
     10.0           82         90
     20.0           97         96

Environmental Impact -  Solid waste, odor  and air pollution impacts are similar
to those encountered with standard activated sludge processes.


Toxics Management  -  The same  potential for sludge contamination,  upsets,  and

pass  through of  toxic  pollutants  exists  for oxidation  ditch  plants as  for
standard activated sludge processes.
Winter
0
0
0
5
57
92
99
Summer
0
0 '
2
12
64
93
100
Winter
33
58
79
92
98
99
100
Summer
48
76
91
95
100
100
100

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                    OXIDATION  DITCH
SCREENED  AND
DEGRITTED
WASTEWATER
                AERATOR I
                ROTOR  *
                 RETURN  SLUDGE
 FINAL
CLARIFIER
  EFFLUENT
                                                      EXCESS
                                                      SLUDGE
                 Figure FS-1.  Flow Diagram

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                                                                     Page FS-5

ENERGY NOTES - Assumptions:

Energy Requirements Based on:

Water Quality      Influent (mg/1)       Effluent  (mg/1)
      BOD                 200                   20
      TKN                  35                   1
Design Assumptions -
Oxygen transfer efficiency   2.5 Ib 02/bhp/hr
Nitrification occurs

Operating Parameters -
Oxygen requirement 1.5 Ib 02/lb BOD removed
                   4.57 Ib 02/lb TKN oxidized

Type of Energy Required - Electrical

COSTS - July 1991 dollars; ENR Index 4854.  Assumptions: Construction costs are
for  the entire  plant but  do not  include land, or  engineering.    O&M costs
include all  costs  incurred  in  operating  the plant  (labor,  utilities,
maintenance materials, etc)

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Figure FS-2.  Construction and Operating Costs and Electrical Energy

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                                                                     Page FS-7
References
Ettlilch,  William F. ,  A Comparison  of Oxidation  Ditch  Plants to  Competing
Processes  for Secondary  and Advanced  Treatment of  Municipal Wastes., U.S.
Environmental Protection Agency, Municipal Environmental  Research  Laboratory,
Office of  Research and  Development, Cincinnati,  Ohio,  EPA-600/2-78-051,  March
1978.

Innovative and Alternative Technology  Assessment Manual,  Office  of  Water
Program Operations, Washington, D.C.  and Office of Research and  Development,
Cincinnati, Ohio,  U.S. Environmental Protection Agency, February 1980.

Preliminary Draft  Evaluation  of Oxidation Ditches For Nutrient Removal,
Prepared by HydroQual, Inc.,  September 1991.

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                                                                        Page 1-1
                                   SECTION 1.
         THEORY OF NITRIFICATION, DENITRIFICATION AND  PHOSPHORUS REMOVAL

      The  following  sections  describe  the biological processes  that  occur
  naturally in  the  environment and which can be encouraged  to  take place  for
  wastewater treatment.

  NITRIFICATION

      Nitrification  is  the biological  oxidation of  ammonia  (NH4+)  to  nitrite
  (N02~)  and  then  to  the nitrate   (N03_)  form.    The  two  major  species of
  microorganisms responsible for the biological oxidation of  nitrogen compounds
  are  the autotrophic  bacteria  Nitrosomonas and  Nitrobacter.   Nitrosomonas
  oxidizes ammonia to nitrite.   Nitrobacter  completes  the nitrification  process
  by oxidizing nitrite to nitrate.

      The  overall nitrification of ammonia  can  be expressed by the following
  reaction:

                        NH4+ +  202 ---> N03" + 2H+ + H20

      Temperature,  pH,  and  dissolved  oxygen concentration  are  important
  parameters  in  nitrification kinetics.   The  rate  of  nitrification in an
  activated sludge system  decreases  with decreasing  temperature.   The  optimum
  temperature  is between 25  and  35G.   The optimum pH for nitrification is in  the
  range of 7.5 to 9.0.  Below pH 7.0 and  above pH 9.8  the nitrification  rate is
y less than 50 percent of  the  optimum.   Alkalinity  is  destroyed by the oxidation
  of  ammonia,  thereby  reducing the  pH.    A ratio  of  7.14  mg alkalinity is
  destroyed per mg of ammonia nitrogen oxidized.   Aeration partially strips  the
  carbon dioxide  from  the  wastewater  thereby reducing alkalinity reduction;
  however,  enough  alkalinity must remain in the wastewater so as not to  depress
  the pH.  Maximum nitrification rates occur at  dissolved oxygen concentrations
  greater than 2 mg/1.  The  nitrification process  consumes 4.57 Ibs of oxygen  per
  pound of ammonia nitrogen  converted to nitrate.C2)

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                                                                       Page 1-2

     The nitrification rate  is also  dependent on  the  fraction of  nitrifying
 bacteria  present  in  the  system.    A principal  means  of increasing  the
 nitrification  rate is  to  increase the  fraction of nitrifiers.   This can be
 accomplished  by increasing  the  aeration basin  mixed  liquor suspended  solids
 (HLSS)  concentration.   Lowering  the ratio between the 5-day BOD and the  total
 Kjeldahl nitrogen  concentration  (BODs/TKN)  by nitrifying in a separate  second
 stage aeration  system also increases  the percentage  of nitrifiers.    This
 increase  in nitrifiers increases  the nitrification rate.(2)   This  approach,
 however, has not been  found  to be  a cost effective  design for normal municipal
 wastewater.                           ,

 DENITRIFICATION

     Biological,  anoxic denitrification is a process  in which nitrate  is reduced
 to  nitrogen  gas  by  microorganisms  in the  absence  of  dissolved oxygen.
 Denitrification  can  occur  provided a sufficient source  of nitrate and organic
 carbon  are present.    The  denitrification process can be  expressed  by  the
 following reaction:

                   NOs" + organic carbon	> N2(gas) + CC>2

    The denitrification process occurs  in two  steps.   The first step involves
 the reduction of nitrate to  nitrite.  In the second step  nitrite is  reduced to
 produce  nitrogen  gas.  Many species of  facultative  heterotrophic  bacteria,
 including Psuedomonas,  Micrococcus,  Archromobacter, and  Bacillus  can convert
 nitrate to nitrogen gas.   Nitrate  replaces  oxygen in the  respiratory processes
 of the organisms capable of denitrification under anoxic conditions,(2)

    Environmental  factors including temperature,  pH,  and dissolved  oxygen
 concentration have an  effect on  the rate of denitrification.   Denitrification
 occurs at temperatures  in the range of 10 to 30C.   The rate of denitrification
 is reduced below pH  6.0  and  above pH 9.0.  The  optimum pH is in the range of
6.5  to  8.0.   A dissolved oxygen  concentration greater   than 1  mg/1 inhibits
denitrification.

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                                                                      Page 1-3
PHOSPHORUS REMOVAL
    Phosphorus in wastewater may be present  as  orthophosphate,  polyphosphate,
or organic phosphorus.   Orthophosphate  is  the more  easily removed of  the three
types .of phosphorus.    Polyphosphates  are converted to  orthophosphate by
hydrolysis  and  organic phosphorus  is converted  to  orthophosphate through
bacterial decomposition.(3)

    Conventional,  secondary biological  treatment  systems  accomplish partial
phosphorus  removal  by  using phosphorus  for biomass synthesis  during  BOD
removal.  A typical phosphorus content  of  microbial solids is 1.5 to  2 percent
based on dry  weight.   Wasting excess biological solids with 1.5 to  2 percent
phosphorus content results in a total phosphorus removal of 10  to  30 percent.
The percent phosphorus  removal is dependent on the BOD to phosphorus ratio, the
system sludge age,  sludge handling techniques and sidestrearn  return  flows.(3)

    Additional  biological  phosphorus  removal  will  occur  if  wastewater is
subjected to  both  anaerobic  and  aerobic  conditions.   When an anaerobic stage
(absence of DO and oxidized  nitrogen) precedes an  aerobic stage, fermentation
products  are produced  from the  BOD in the  wastewater  by   the action of
facultative organisms.    The phosphorus storing microorganisms   can assimilate
the fermentation products  under  anaerobic conditions.   Since  many  competing
microorganisms  cannot  function  in  this manner,  the  phosphorus storing
microorganisms have a distinct advantage  over other organisms in the  activated
sludge  system.   Thus,  the  anaerobic  phase  results  in  the development of
phosphorus storing  microorganisms.(3)

    The stored substrate products are depleted in the  aerobic phase  and soluble
phosphorus taken up by the microorganisms  in quantities in  excess  of what is
needed  to function.   This  "luxury uptake"  of phosphorus  is maximized at
dissolved  oxygen concentrations greater  than  2  mg/1.   At  lower DO
concentrations the  excess phosphorus will be released from the microorganisms.

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                                                                     Page  1-4

    For biological phosphorus removal to occur, an anaerobic stage is  required
for  the production of  the fermentation products.    If nitrification  is
occurring,  a  denitrification  step must  occur before  enhanced biological
phosphorus  removal.  If nitrite or  nitrate are present, the system is  anoxic
rather than anaerobic.

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                                                                       Page 2-1
                                   SECTION 2.
                       DESCRIPTION  OF THE OXIDATION DITCH

 INTRODUCTION

     The  original oxidation ditch  designs used  in the Netherlands were earthen
 ditches  in a race track configuration.  The  modern  design trend for oxidation
 ditches  in the  United  States  is concrete  construction  in  a race  track
 configuration.   There are several configurations and modes  of operation used.
 The  most  commonly  used configuration  is  the  single channel design,  but the
 multiple  concentric channel design is also used quite frequently.

     Oxidation  ditch plants generally have  pretreatment before  the  raw sewage
 enters  the ditch.  Pretreatment  is  generally bar screens, comminutors,  and a
 grit chamber.   Primary  settling prior to  an  oxidation ditch  is  sometimes
 included, however, it  is not common.  Flow to the oxidation ditch is mixed with
 return  sludge from a secondary clarifier  and is mechanically aerated.    The
 mechanical aerators may be brush rotors, disc aerators, surface aerators,  draft
 tube aerators,  or fine bubble diffusers, depending on  the design.   The liquid
 in the ditch typically completes  a circuit every 5 to  20  minutes depending on
 the channel length, flow and velocity.   Effluent from the oxidation ditch flows
 to secondary clarifiers for settling before discharge.

    The  single  channel oxidation  ditch may.  be found  in  a  variety of shapes
 including ovals, horseshoes or  ells, whichever best  fits a site.  The  various
cdnfigurations  are illustrated on  Figure  1A.   The  concentric  multichannel
design is illustrated on Figure IB.  The number of concentric  rings ranges from
 two  to  five.   Oxidation ditches  are  typically followed  by  a  separate  final
clarifier, however, one modification incorporates a clarifier  in the  oxidation
ditch channel.

-------
CIRCULAR
               OVAL
                            ELL
                                              HORSESHOE
     Figure 1 A.  Single Channel Oxidation Ditch - Typical
                   Channel Configurations
                                                      (Ref. 1)
  TRANSFER PORTS
  (between channels)
                              O
                                                     (Ref. 1)
  Figure 1B. Multiple Concentric Channel Oxidation Ditch - Typical
                           Schematic

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                                                                        Page  2-3
  DESIGN VARIATIONS
      There are  many variations  on the  original oxidation  ditch design  that
  incorporated brush  aerators  followed by  a separate  secondary clarifier.  These
  variations include  different types of aeration equipment such as  disc  aerators,
  draft tube  .aerators,  and  surface  aerators  and  the use of  intrachannel
  clarifiers.   Three oxidation ditch suppliers  that  represent the major design
  variations were  contacted.    Oxidation  ditches similar  in design  to those
  marketed  by the  three  manufacturers  contacted are  marketed by several other
  companies.

      Table 1 presents the most commonly used configurations, and  the aerator and
  clarifier type  commonly used by the manufacturers contacted.   Also  presented
  in Table  1 are the modifications to  each design for  nutrient  removal.   The
  following paragraphs  describe  the   specific designs  of  the  manufacturers
  contacted.

  Eimco

      Oxidation  ditches supplied by  Eimco  are  referred  to  as  the  Eimco
  "Carrousel" Oxidation Ditch  System.  A schematic of  a typical Carrousel system
  is presented in Figure  2.    Information received from  Eimco  in June   1991
  indicated that a total of 169 Carrousel systems were in  operation  in the United
  States.   The design flows of these plants  range from 0.1 to  25.6 mgd.  Eimco's
  literature states  that  Carrousel plants can treat  raw  domestic wastewater to
  advanced  secondary standards without primary clarifiers  or effluent fliters.(4)
  Eimco  traditionally has marketed the  Carrousel system in wastewater  treatment
  applications where the effluent permit requirements  were 30:30 or 20:20 as mg/1
  of BODs:mg/l  of TSS.    Eimco has  also  marketed   the  Carrousel system  for
~  applications in which partial or total  nitrification is required.    Carrousel
  Systems have been designed to meet  permit limits of 10:15:1  as mg/1  BOD5:mg/l
-"  TSS:mg/1 NH3-N.(4)

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TABLE 1.  OXIDATION DITCH SUPPLIERS CONTACTED


Manufacturer
Eimco
Envirex
Innova-Tech
Lakeside



Typical
Configuration Aeration Method
Racetrack Mechanical
(Carrousel) Surface Aerators
Concentric Channel Disk
(Orbal)
Racetrack Draft Tube
(Barrier
Oxidation Ditch)
Racetrack Brush Rotor
(Closed Loop
Reactor)


Clarifier
Most
Commonly Used
External
External
External
External

Nutrient
Removal
Design
System
Bardenpho
SIM-PRE
Anoxic zone
Anaerobic
basins
Modified
Ludzach-
Ettinger
Process

-------
                           -TO SECONDARY
                            CLARIFICATION
                                         BASIC CARROUSEL SYSTEM
    Q	.
                           -TO SECONDARY
                            CLARIFICATION
                                         MODIFICATION OF BASIC CARROUSEL SYSTEM
                                         FOR PARTIAL DENITRIFICATION - ANOXIC ZONE
                                         IN CHANNEL
          db-~0
              1-4Q
                         --TO SECONDARY
                           CLARIFICATION
                                      MODIFICATION OF BASIC CARROUSEL SYSTEM
                                      FOR DENITRIFICATION -ANOXIC ZONE IN CHANNEL
                                      AND UPSTREAM ANOXIC TANK
    cb
                                      MODIFICATION OF BASIC CARROUSEL SYSTEM
                             _       FOR DENITRIFICATION - ANOXIC ZONE IN CHANNEL
                            TO SECONDARY AND UPSTREAM AND DOWNSTREAM ANOXIC TANKS
                                      (BARDENPHO PROCESS)
        1-4Q
i
!
    *
-O
d)
        1-40
MODIFICATION OF BASIC CARROUSEL SYSTEM
FOR DENITRIFICATION AND PHOSPHORUS REMOVAL
- ANOXIC ZONE IN CHANNEL - UPSTREAM
FERMENTATION TANK AND UPSTREAM AND
DOWNSTREAM ANOXIC TANKS
(MODIFIED BARDENPHO PROCESS)

                          (Ref. 5)
Figure 2. Basic Carrousel System and Modifications for Nutrient Removal

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                                                                       Page 2-6

    Host  of  the  Carrousel systems  in the United  States  are  designed to be
operated  in the extended  aeration  mode that implies  a  solids retention time
(SRT)  of 20  to  30 days.   The long  SRT's  enable the system  to  absorb shock
hydraulic loadings, toxic  shocks, and diurnal fluctuations in both quality and
quantity  of incoming  wastewater.   These long SRT's  are  conducive to  complete
nitrification

    Aeration in the Carrousel  system  is provided by low speed surface  aerators
mounted at turns  in  the  racetrack  configuration.    Plug  flow exists in the
channels between the aerators.  Flow  velocity is maintained in the channels by
the pumping action of the  aerators.   This pumping action is achieved by lining
up the partition walls with the aerators so  the  aerators pump mixed liquor from
the upstream  channel  into  the aeration zone.   In the aeration zone the mixed
liquor is completely mixed and forced into  the downstream channel.

    The aerators in the Carrousel oxidation  ditch  system are typically  designed
for 0.4 HP  per  1000 cubic  feet.   The power draw of the aerator can be changed
by lowering or  raising  a variable height overflow weir located on the outside
wall  of the  basin.    This weir  controls  the  water  level  in the basin  and
therefore the  impeller  submergence.    The  power drawn and  oxygen transferred
increases  with  increasing  impeller  submergence.   According   to  the
manufacturer's information, aerator horsepower  can be varied  from 100 percent
to 25 percent of installed capacity without loss of adequate mixing for solids
suspension and oxygenation.(4)

    Modifications  may be  made  to  the Carrousel  system  to  achieve
denitrification.  To achieve partial  denitrification in addition to BOD removal
and nitrification,  an  anoxic  zone is  added in  the  channel  upstream  of  the
aerators.   The anoxic zone in the basin channels is created by controlling the
amount of air produced  by  the  aerators.   This modification  is  shown in Figure
2.  A DO  of approximately  2 mg/1  in the aerobic zone  decreases in the channel
and approaches zero in the  anoxic  zone.

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                                                                       Page 2-7

     To  meet a  total  nitrogen effluent  requirement  of less  than 10  mg/1,  a
 Carrousel system with a  separate  upstream anoxic  tank for denitrification can
 be added to the design.   A schematic  of  this modification is shown in Figure 2.
 The denite  tank is  an uncovered  tank with submerged turbine mixing equipment.
 This anoxic tank is used in addition to the anoxic zone in the channel.  Up to
 400 percent of  the  influent  flowrate is recycled to  the  denite  tank from the
 Carrousel basin at a point near the downstream end of the anoxic zone.

     A second anoxic  stage  may  be  added  to  the  above design for  further
 denitrification.   This  second anoxic  stage,  which follows the oxidation ditch,
 is used to  reduce the remaining nitrates  to  a  level of 1 mg/1 or  less.   This
 stage is followed by a reaeration stage to strip the  nitrogen gas.   This four
 stage system is referred to as the Bardenpho Process. (6)  A schematic  of this
 modification is  presented in Figure 2.

     A fifth stage  may  be added to the Bardenpho Process  if  biological
 phosphorus  removal  is   required.   This  fifth stage  is  referred to  as a
 fermentation stage  and usually consists  of two  cells in series.   Each  cell is
 typically  a  concrete  tank  equipped  with  submerged  turbine  mixers.
 Concentrated sludge  from the secondary  clarifiers  is  returned to this stage.
 This  creates an anaerobic environment where the bacteria are stressed  causing
 phosphorus within  the  cells  to  be  released.    When exposed to  an aerobic
 environment, the uptake of phosphorus  is  greater than if  the  organisms were not
 previously  exposed to a  stressed environment.    A schematic of  this process
 known as Modified Bardenpho Process(6) is presented  in Figure 2.
Envirex
    Oxidation  ditches  supplied by  Envirex are  called  "Orbal" systems.   The
Orbal system is  typically  a three channel looped reactor system,  although two
channels may be  used in very small flow  systems  (less  than 0.2 mgd). (7)   A
typical  three  channel  orbal  aeration  basin  is  shown  in  Figure  3.   An
installation list received  from Envirex in May  1991  indicated there were 171
Orbal systems treating municipal waste  in  the United States.(7)

-------
  . SIM-PRE INTERNAL
  RECYCLE CHANNEL
(FOR NITROGEN REMOVAL)
RETURN SLUDGE
  INFLUENT-
                                                 EFFLUENT TO
                                                  CLARIREH
                                                      (Ref. 7)
  Figure 3. Typical Three Channel Orbal Oxidation Ditch
           With Modification For Nutrient Removal

-------
                                                                        Page 2-9

     Most of the Orbal systems in the United States  are  designed to be operated
 in the extended aeration  mode.   Solids retention times in  these  systems  range
 from 20  to  38  days.   The  long  SRT's  are conducive to  complete nitrification.
 Design BOD  loadings  in these systems  range  from 12.5  to 20 Ibs  BOD/day/1000
 cubic feet.   For  treatment plants  with flows  greater than 2 mgd,  the extended
 aeration system design is  used only when nitrification is  required.

     Aeration in  the  Orbal system  is  provided  by  4.5 foot  diameter  plastic
 aeration disks.  Triangular nodules on the surface  of the molded plastic  disk
 provide mixing  and aeration.   The nodules have  a  base  face and an  apex face and
 can be run  with either entering  the  mixed liquor  first... This  reversing of
 direction  is  accomplished by  reversing  the drive  rotation  of  the disks.
 According to manufacturer's literature the  base face provides  one third  more
 oxygen than  the apex  side.   The  disks have an immersion  operating range  of  from
 21  to  9  inches,  allowing  for adjustment of  oxygen delivered and power drawn
 with  influent variations.    This adjustment ranges  from 50 to  100 percent of
 that  at maximum immersion  of the disks.   Velocity in the ditch is maintained by
 the rotation of the disks.

    Manufacturer's  information indicates that  the Orbal system  needs  only one
 horsepower per  100,000 to 200*,000  gallons for efficient mixing. (8)   Typical
 rotational speed for  the disks is 43 rpm but may be  adjusted upwards to 55 rpm
 to  supply additional oxygen.   Manufacturer's  literature also  states  that
 nitrogen  and phosphorus removal  rates of  80 percent and ammonia effluent levels
 below 1 mg/1 can be achieved with a standard extended aeration Orbal system.(8)

    Regulatory agencies in some  states  may require dual  aeration basins.  When
 this  is  required  the Orbal  system is  designed with  individual  dewaterable
 channels  and influent  and  return sludge lines  to all  three  channels.   In  this
 design the first channel has 50 percent of the  total  basin volume.

    In  the standard three  channel  extended air  Orbal system,   the  wastewater
flow normally enters  the  outer  channel.   Oxygen delivery rates in the first
channel are higher  than  in the  other two channels.   The aerated zones  in  the
first channel provides oxygen  for nitrification.   The actual oxygen demand in

-------
                                                                      Page 2-10

 the first channel exceeds  the  oxygen  supplied and an oxygen deficit condition
 is established.  Despite the oxygen deficit,  most ammonia  is  nitrified in the
 first channel.   Denitrification  occurs  as the nitrates pass  through  zones  of
 zero dissolved oxygen in the channel.   The second channel works with the first
 channel for  further nitrification and  denitrification.   The  third innermost
 channel is used for further reduction of BOD and any necessary final reduction'
 of ammonia.

     Modifications may be made to  the standard Orbal system to  achieve  nitrogen
 removals  greater than 80  percent.    The modification,  called  the  SIM-PRE
 process,  include an  internal  recirculation loop where residual nitrates  from
 the third channel are recycled  to  the  first channel.   This  recycle  rate  is
 usually four times  the influent  flow.   The process  uses  the  simultaneous
 nitrification-denitrification available with the standard Orbal system  plus the
 recirculation of  residual  nitrates  to  achieve  additional  biological
 denitrification.

    An additional  modification  also  may  be made  to  the  Orbal  system for
 biological phosphorus  removal.   To enhance biological phosphorus removal, the
 system is  designed with an oxygen deficit.  This  creates anaerobic  conditions
 resulting in  phosphorus  being released from the solids.  In  the  inner  channels
 where  aerobic conditions exist, the solids take  up more phosphorus than  they
 originally contained, thus increasing the biological phosphorus removal.

 Innova-Tech

    Oxidation ditches  supplied by  Innova-Tech  are known  as "Total  Barrier
 Oxidation Ditch" systems.  A typical Total Barrier Oxidation Ditch is shown in
 Figure 4.   A  variety  of ditch designs  and configurations  are  available
 depending on system requirements and available  land.   Information received from
 Innova-Tech in June  1991 indicated that a total of 57 systems were installed in
 the United  States,  36  of  which were at municipal plants.   The design flows
ranged from 0.04 to  7.0 mgd.

-------
                TOTAL  BARRIER  OXIDATION  DITCH
VA'STEWATER
INFLUENT
                                  -TOTAL  BARRIER
                                       WALL
NITRIFICATION
  OCCURS
                             DRAFT TUBE
                             AERATORS
                                        BLOWER

                                         BLDG-
DENITRIFICATION
     OCCURS
                    DRAFT TUBE a AERATOR  DRIVE
                                            pANTI VORTEX
                                             INTAKE BAFFLES
                   TOTAL BARRIER WALL

                   AIR SUPPLY TO
                  CONTACT DIFFUSER
                       DUCT
           CONTACT DUCT
          DIFFUSER ACCESS
               DUCT


         (Optional) REMOVAL CONTACT
             DUCT DIFFUSERS
                                         HORIZONTAL OR VERTICAL
                                            AERATOR  DRIVE
                                              >AIR SUPPLY  FROM BLOWER
                                                TO  AIR SPARGE
                                                      ANOXIC
                                                      ZONE
                                           DRAFT TUBE
                                           AIR SPARGE
                         DEEP OXYGEN
                        CONTACT  DUCTS
                                                              (Ret. 10)

                 Figure 4. Total Barrier Oxidation Ditch and Draft Tube

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                                                                       Page 2-12

     Once design parameters are established by  the  design engineer,  Innova-tech
 recommends  the wastewater treatment  process  design  and system  to meet  the
 required treatment needs.

     The Total Barrier Oxidation Ditch differs  from traditional  oxidation ditch
 systems in that a vertical barrier wall is  installed  across the entire  cross
 section of the ditch channel.   The wall prevents backmixing  and forces  all  the
 flow into the draft tube turbine  aerators.  Compressed  air is introduced to  the
 turbine  assembly  through  a sparge ring located beneath  the turbine  blades.
 Aerated mixed liquor  is  discharged below the  water surface  on the  downstream
 side of the barrier wall  through a J-tube extension of the  basic draft  tube.
 The  turbine part  of  the draft tube turbine  aerator provides enough energy to
 circulate liquid through the ditch, while blowers deliver air to the  draft tube
 turbine aerators  for  aeration.   The use of  separate devices for aeration  and
 mixing  allows for independent control of channel velocity and  oxygen transfer
 rate.   Manufacturer's  information indicates that, except in very large  plants,
 no more than two  aerators are  required and they are placed side by side at  one
 location.  Oxygen  transfer  efficiencies of 4.0  to 5.0 Ibs 02/bhp/hr at standard
 test conditions are claimed by the  manufacturer.(9)

     The Barrier Oxidation  Ditch  may be  operated with  an anoxic zone  in  the
 channel to promote denitrification as  long as  the  channel is long enough  for
 both aerobic  and  anoxic zones.   If biological  phosphorus removal is required,
 the  Barrier  Oxidation Ditch may be modified  by adding  an anaerobic tank prior
 to the  oxidation  ditch.   In this system there  is an internal recycle from  the
 anoxic  zone  of the  ditch  to  the anaerobic  tank.   Sludge from the secondary
 clarifier  is returned  to  the anoxic  zone  of  the  oxidation  ditch  to prevent
nitrates  (thereby oxygen) from being introduced to the anaerobic tank.

Lakeside

    Lakeside furnished the  first  oxidation  ditch  plant  in the United States in
1963.   Oxidation  ditches  supplied by  Lakeside  are called   the  "Closed Loop
Reactor Process"  (CLR).   The CLR process consists  of a single channel reactor

-------
                                                                     Page 2-13

with a single feed point for raw sewage and return sludge.  A typical Lakeside
oxidation ditch is presented  in Figure 5.   Information received from Lakeside
in  August 1991  indicated  there are  approximately  1500 operating  Lakeside
oxidation ditches.

    Lakeside  literature states that  the  CLR  process can  provide effective
secondary biological treatment with BODs and suspended solids reductions of 92
to  99 percent.(10)   Manufacturer's  literature  states that the CLR process can
achieve  95 to  99 percent  nitrification  and  high  levels  of denitrification
simultaneously  without major  modifications. (H)   According  to manufacturers
information,  single reactor designs  can be  utilized to achieve a total nitrogen
level of  approximately 10 mg/1  depending  upon mixed  liquor  temperature.   In
warm climates lower total nitrogen concentrations may be achieved.

    The  CLR  process  operates  in  the  extended aeration mode  with  a long
detention  time  (18  to 32 hours),  a well  conditioned sludge,  and  high MLSS
concentrations  (3000  to  9000  mg/1).   Hydraulic and organic surges  have  no
significant   effect  on the  process  efficiency according to  manufacturer's
information.   These operating conditions promote nitrification.

    Aeration  in  the  CLR  process  is  provided by   horizontal bladed rotor
aerators.   The rotors  are low speed mechanical  surface aerators that rotate in
a plane horizontal to the liquid surface.   Three rotor types, Cage, Mini-Magna,
and Magna are available.(10)   xhe Cage and  Mini-Magna rotors have a speed range
of  from 60 to 90  rpm and  a minimum  design  immersion  of six inches.   The Magna
rotor has a speed range of from 50 to  72 rpm and a minimum design immersion of
eight inches.   The oxygenation capacity of the  rotor may be varied by changing
the  immersion and rotational speed.   The  velocity  in the ditch  varies with
rotor length, rotor  speed,  rotor immersion,  ditch  configuration,  ditch depth,
ditch liner  and rotor baffles.   Typically  a  velocity of  at least 1  fps  is
required to maintain MLSS in suspension.

-------
           RETURN
           SLUDGE
    INFLUENT
                                  ROTOR
''/,.
FLOW


"HIGH DO
                       TYPICAL LAKESIDE OXIDATION DITCH
                                                               EFFLUENT
RawWsstewater/
Return Sludge
Blending Tank

                            I
                                 ANOXIC
                                 BASIN
                                  FLOW
                                  	
                                 DO*i(M.5mfl/L^/
                                          
            ROTOR

AEROBIC
 BASIN
                                   FLOW
                                  	^,

                                  DO2.0mg/L
                 Recycle

                      EFFLUENT

                    MODIFICATION FOR NUTRIENT REMOVAL       (Ref. 11)
                       (Modified Ludzack-Ettinger Process)

         Figure 5.  Lakeside Oxidation Ditch and Modification for
                             Nutrient Removal

-------
                                                                       Page 2-15

     A modification may be  made to the CLR  process  to meet stringent  nitrogen
 effluent limits  (less  than 5  mg/1)  and  to enhance  phosphorus  removal.    This
 modification is  the  Modified Ludzack-Ettinger (MLE) process.   A schematic  of
 this process is presented in Figure  5.   This  process consists of two  separate
^aeration basins,  the first anoxic and the  second aerobic.   The basins operate
 in series with the mixed liquor being recycled from the aerobic reactor to the
 anoxic  reactor.    Manufacturer's  literature  states  that 83  percent nitrogen
 removal  can be  expected at  a  mixed  liquor recycle ratio  of 4 and a return
 sludge ratio of one.

-------

-------
                                                                       Page 3-1
                                  SECTION 3.
                               PERFORMANCE DATA

INTRODUCTION

    Treatment plants  with oxidation  ditches and  nutrient removal  data were
identified by EPA personnel and the ditch manufacturers.   The effluent permit
limits  and type of  oxidation  ditch  for  the plants  that provided  data are
presented in  Table 2.

    Eight of  the 17 plants have effluent ammonia permit  limits.   These limits
ranged from 0.5  to  3.0 mg/1 during  the summer months.   One plant, Lake Geneva,
Wisconsin,  that  discharges to  seepage cells has a year round  total nitrogen
limit of  10 mg/1.  The Crofton,  Maryland plant has a  seasonal  total nitrogen
limit of  10  mg/1.   Thurmont, Maryland,  Fredrick,  Maryland, and Wanaque,  New
Jersey have a Total  Kjeldahl nitrogen  limit during the  summer months.   The
Yellow River/Sweetwater Creek Water Reclamation Facility has a nitrate limit of
6.0 mg/1  year round.    Six  of the plants have effluent phosphorus limits that
range from 0.5 to 2.0 ing/1.

    Design information for  the  17 plants is presented in Table  3.   All design
information was not available for each of the plants.   The  average design flow
for the plants ranged  from  0.1  to 12 mgd.   The design hydraulic  retention time
at the average design flow ranged from  10 to 34 hours.   The design mean cell
retention time,  available for eight of the  plants,  ranged  from  12 to 48 days.
The design MLSS concentration, available for 12 of the plants,  ranged from 1500
to 8000  mg/1.   Design BOD loadings  of 13  plants  which provided information
ranged from 5.8 to 39.2 Ibs BOD/day/1000 cubic feet.

    The performance  data for  the  17  plants  are summarized in  Table 4.   The
average  flow ranged  from  30 to 116  percent of  design.    Actual  hydraulic
detention times ranged  from 10.7 to 57 hours.  The  average  effluent BOD ranged

-------



















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                                       TABLE 3.  DESIGN BASIS FOR OXIDATION DITCH PLANTS
Dupage County
Illinois
Cedarburg Dousman (Knollwood
Wisconsin Wisconsin
Design Flow (mgd)
Aerator Type
Influent BOD (mg/1)
Influent NH3-N (mg/1)
Influent Total P (mg/1)
Design Nitrification?
Design Denitrification?
Design Biological F Removal?
Design BOD Load (Ib/1000ft3/day)
Design MLSS (mg/1)
Design Hydraulic Detention Time (hrs)
Design SRT (days)



Design Flow (mgd)
Aerator Type
Influent BOD (mg/1)
Influent NH3-N (mg/1)
Influent Total P (mg/1)
Design Nitrification?
Design Denitrification?
Design Biological P Removal?
Design BOD Load {Ib/1000ft3/day}
Design MLSS (mg/1)
Design Hydraulic Detention Time (hrs)
Design SRT (days)
2.75
disc
200
20
5
Yes
No
Yes
12.2
8000
24
30
Huntsville
Texas
(South Plant)
1.60
disc










0.3S
disc
200


Yes
No
No
12.0
3000
24
48

Kemmerer
Wyoming
1.45
surface
180


No
No
No

3750

30
Plant)
8.3
draft tube
215
25

Yes
No
No
15.9
3500
20


Lake Geneva
Wisconsin
1.74
disc
153
18
3.2
Yes
Yes
No
15.0
4000-5000
15
22
Frederick
Maryland
7.0
fine bubble



Yes
No
No

2500
12.5


Lyons
Wisconsin
0.10
brush
271


Yes
No
No
13.0

31.5

Hanover
Huntsville
Texas
Pennsvlvani a (Parker Creek)
3.65
brush
153)
draft tube
100


Yes
No
No


29.0


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Maryland
1.0
brush
75(a)
36 (TKN)

No
No
No
11.1
4000-4500
10.


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Wanaque Sweetwater Creek
Hew Jersey
0.7
surface
250
25
10-12
Yes
No
No
12.7
5000
29.5

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12.0
disc
250
25
10
Yes
Yes
No

3500
11.4
15

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                                                                        Page 3-6

 from 1.9 to 10.5 mg/1 with removals ranging from 90 to 99 percent.   The average
 BOD loading ranged from  2.5  to  15.8 Ibs BOD/day/1000 cubic feet.   Nine  of the
 ten plants  where both  design and  actual  loadings were  available were  below
 design.   The load to  one plant exceeded the design BOD loading.

     Nitrate,  total nitrogen,  and  phosphorus  data were  limited.   Effluent
 phosphorus data were  available for seven plants.  Chemicals were added at five
 of the plants for higher phosphorus removals.  These plants typically  achieved
 effluent phosphorus levels  less  than 1  mg/1.   The  monthly average data  for each
 plant  is presented in Appendix A.   Chronological plots of the  data are  also
 presented in Appendix  A.

     Effluent ammonia data indicates  that nitrification was occurring at all the
 plants.    TKN and  N03-N data from  two plants  designed  for denitrification
 indicated that denitrification was occurring when  operated in a mode to promote
 denitrification.  The  Patuxent Water Reclamation Facility in Crofton, Maryland
 was  designed for  denitrification, however, during  the winter it is not operated
 to promote denitrification.

 SITE OBSERVATIONS

    Three of the  17 plants  that  provided data were selected for site visits to
 obtain detailed  information on operations  and performance.   The three plants
 selected  monitor  ammonia, nitrate  and  phosphorus.   The three plants  visited
 represented  three  types of  aeration  equipment  -  brush  rotor,  fine  bubble
 diffuser  and draft  tube aerator.  One  plant (Thurmont) was designed for only
BOD removal.   One plant (Fredrick) was designed for nitrification and the third
plant (Patuxent Water  Reclamation Facility) was  designed for nitrification and
denitrification.

    The following discussion summarizes  the  observations made at the plants.

-------

-------
                                                                        Page  3-7

 Thurmont. Maryland

     The  Thurmont,  Maryland  wastewater  treatment plant  was designed for an
 average daily flow of 1 mgd,  and a peak flow of 4 mgd.  The plant was  designed
 to treat an influent BOD of 210 mg/1, an influent TSS of 230 mg/1 and  a TKN of
 36 mg/1.

     The current treatment plant  is an upgrade of a trickling filter plant.  The
 oxidation ditch was  completed in 1983.  The influent flow passes through a grit
 chamber,  comminutor  and bar screens prior to primary clarifiers.  The plant has
 three primary  clarifiers,  however,  only two  were  in  service.   The  primary
 clarifier effluent  flows either  directly to  the oxidation  ditch  or  to  the
 trickling filter before  the oxidation ditch.   Flow cannot  be split between the
 trickling filter and  the oxidation  ditch.   The  trickling filter was  used in
 addition to  the oxidation  ditch from  mid May until August 19,  1991.   The
 oxidation ditch effluent is  settled in  two  secondary clarifiers operated  in
 parallel.   The  clarified effluent is polished by  sand filters and disinfected
 using ultraviolet light.  The effluent  is discharged  to  Hunting  Creek,  a Class
 III  trout stream.

     The plant's  effluent permit  limits are a 30 day average  BOD  of 30 mg/1  and
 a  30 day average TSS  of  30  mg/1.   From  May  through  October  the  effluent  TKN
 limit is  a 30 day average of  3  mg/1.  The plant  is  also required to  monitor
NH3-N, NOs-N and phosphorus  and report the results  although there are no permit
limits for these parameters.

    The  state of Maryland is  in the  first  phase  of  a  biological nutrient
removal program in which Thurmont is participating.  As part of a  study, which
started in  October  1990,  existing treatment plant  operations are being
evaluated and nutrient levels monitored.   Treatment plants with operations that
could be  upgraded for nutrient  removal without extensive  modifications were
included in the  study.

-------
                                                                       Page 3-8

    The oxidation ditch is a Lakeside ditch with  two brush rotor aerators with
BL  maximum immersion  of 7.5  inches.    The  ditch was  designed  for  a 10  hour
hydraulic detention time at  the  design  flow of 1 mgd.  The ditch was designed
for an  organic loading of 4.6 Ibs  BOD/day/1000 cubic ft.   The  manufacturer's
recommended MLSS concentration was 4000 to 4500 mg/1.   The secondary clarifier
was designed for a 5.4 hour  detention time at  the average design flow of 1 mgd
and an overflow rate of 300 gpd/ft2.

    The oxidation  ditch is operated at a MLSS concentration  of approximately
1800 mg/1 in  summer  and approximately  3000 mg/1 in winter.  The return sludge
concentration in the summer is 6000 mg/1 and 8000 mg/1 in winter.  Operation of
the ditch at the higher solids concentrations specified in the  design was tried
but was not  successful.   The  plant  superintendent  felt that  the  secondary
clarifiers did not have the capacity to handle a higher  solids  concentration.
The ditch was operated at an SET .of 5 to 10 days.

    During the period of January  1991  to July 1991  the plant  operated  at an
average  flow  of 0.64 mgd or  64 percent  of  design.   For  the  period of May
through July the trickling filter was in use.  Chronological plots of BOD, TSS,
and TKN are presented in Figure 6.  The plant consistently met  the effluent BOD
and TSS permit limits of 30 mg/1.

    Final effluent TKN  concentrations measured during  May, June, and July 1991
were  2.1,  1.8,  and  1.4 mg/1,  respectively.   Partial nitrification  may have
occurred  in  the trickling  filter, however  this  was not measured.    Final
effluent N03-N was measured  several times  during  the  period April through July
and ranged from 2.2 to 8.0 mg/1.

    The plant  superintendent was generally satisfied  with the  oxidation ditch,
however he feels  the  aeration  system is  too  small,  especially  for  summer
operation.   A problem has been experienced with a  "wave" developing .in the
ditch  if both rotors  are  set  at  72  rpm.   This  "wave" randomly  occurs and
neither the operator  or the  ditch supplier had an explanation  as to the cause.

-------
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                        January  1991 through July 1991
             Figure 6.  Chronological Plots Of Monthly Average Data
                                Thurmont, Maryland

-------
                                                                      Page 3-10

 To prevent the "wave" one rotor is  sometimes  operated at 54 rpm.  Approximately
 eight weeks prior  to the  site visit both rotors were  set at 72  rpm,  and no
 "wave" developed during that time.

     A problem has been  experienced with  filamentous bacteria  due to a low F/M
 ratio in the ditch during  the  summer.   Chlorine has  been added to control the
 filamentous bacteria  in the past, however since  the plant discharges to a class
 III trout  stream  chlorine  can no  longer  be  used.    Hydrogen peroxide  was
 recommended by the state, however its use killed the biomass.   At the time of
 the site  visit  the  plant  was still  recovering and  trying  to  control  the
 filamentous bacteria.   Operations to  denitrify had been abandoned.

 Fredrick. Maryland

     The  Fredrick,  Maryland  wastewater  treatment plant was  designed for  an
 average daily  flow  of 7.0 mgd and a peak hourly  flow of 16.2 mgd.  The influent
 design BOD,  TSS  and TKN  concentrations were not  available.

     The  treatment  plant went  on  line in  February  1988.   The  influent  flow
 passes through a bar  screen and grit chamber  prior to four  primary clarifiers.
 The  primary clarifier  effluent  flows  to three oxidation ditches that operate  in
 parallel.   Each  oxidation ditch has  an intrachannel clarifier.   The clarifier
 effluent solids  are removed by  sand filters and the  effluent  disinfected  using
 chlorine.   The effluent  is discharged to the Monocacy River.

     The plant  has an  effluent  30  day average BOD limit  of 8.7 mg/1 from May
 through October,  and  26 mg/1 from November through April.  The 30  day  average
TSS  concentration limit  is  26 mg/1.   From May through October  a 30  day  average
TKN  concentration of  2.6 mg/1  must  be met.   The current permit has no  total
nitrogen or total phosphorus  limit, however,  the plant must monitor and report
N02-N  and  N03-N  and  total  phosphorus two times per  month.    The flow to the
Monocacy River cannot exceed 8 mgd on the basis of a  12 month moving average.

-------
                                                                       Page  3-11

     Each oxidation  ditch/clarifier  basin has  a  total volume  of 1.55 million
 gallons.  The volume of each clarifier is  0.34  million gallons  and the aeration
 channel volume is 1.21 million gallons.  The  design hydraulic detention time in
 the aeration portion of the  basin  is  12.5  hours   at  average design flow.
 Aeration  in  the oxidation ditch  is  supplied  by  fine bubble,   submerged
 diffusers.   The  intrachannel  clarifier was designed  for  a 3.5 hour detention
 time and a surface loading rate of 606 gpd/ft2  at the  average design  flow.

     The oxidation ditches  are being  run at a MLSS concentration of between 2000
 and 2500 mg/1  and  an F/M of between  0.13  and  0.15.   The  design  MLSS
 concentration was  not available.   The  ditch is  operated at an SRT of between 19
 and 21  days.

     Figures  7  and  8 present  Chronological plots summarizing the monthly average
 flow,  BOD,  TSS,  TKN,  NH3-N,  N02+N03-N,  and total phosphorus for 1990  and May
 through July  1991.   During  that period,  the plant operated at an  average
 influent flow of 8.1 mgd,  which was above the  average design flow of 7.0 mgd.
 The  average hydraulic  detention time for the period was 10.7 hours.   During the
 same period the oxidation ditch influent BODs averaged 102 mg/1.  This converts
 to an organic  loading  of approximately 14 Ibs BOD/day/1000 cubic feet. Based on
 the  data for  the  period approximately  30 percent of the  raw BODs  is  removed in
.the  primary tanks.  Approximately 90 percent of the BODs  entering  the oxidation
 ditch was  removed before  discharge  to the Monocacy  River.   The TKN removals
 indicated  that nitrification occurred during the  entire period.   The  average
 removal  of  TKN was approximately  87 percent.   The average removal of  ammonia
was  approximately  91 percent.   The  plant  is not being  operated  in  a mode  to
promote  denitrification.   Approximately 25  percent  of  the  phosphorus in  the
 influent is removed during treatment.

    As part of Maryland's biological  nutrient removal  program, an  investigation
was  made  to  determine if any inexpensive modifications to the  oxidation  ditch
could be  made  to achieve denitrification.    It  was  determined that because of
the  clarifier  in the  ditch  there  was  insufficient space  to  set  up  an anoxic
zone.

-------
       10.0
        n nj I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I F
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                                             Summer Effluent BOD Limit - 8.7 mg/C
                                             Winter Effluent BOD Limit - 26.0 mg/r
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                          January 1990 through  July 1991
            Figure 7. Chronological Plots of Monthly Average Data
                                Fredrick, Maryland

-------
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                            January  1990  through  July  1991
             Figure 8. Chronological Plots of Monthly Average Data

                                 Fredrick, Maryland

-------
                                                                        Page 3-14

      The  assistant superintendent noted  that  although  the  three  oxidation
  ditches  are  designed the  same,  they each have  their own "quirks".   This has
  made operation of the ditches somewhat difficult since the same adjustments and
  operating  conditions  do not produce  the same results  in each ditch.   It has
  taken  considerable  time and effort  to  get the  plant to the current  level  of
  operation.

  Patuxent Water Reclamation Facility.  Crofton.  Maryland

      The Patuxent Water  Reclamation Facility  in Crofton, Maryland was  designed
  for an average daily  flow of 6 mgd and a peak flow  of 13 mgd.   The plant was
  designed to treat an influent BOD5  of 250 mg/1, an  influent TSS of 200 mg/1, an
  influent TKN of 25 mg/1, and an influent  total phosphorus  of  10 mg/1.

      The treatment plant  began operation  in  April  1988.    The  influent flow
  passes  through bar  screens and a  grit  chamber before  entering  two oxidation
  ditches operated  in parallel.    The  oxidation ditch effluent flows  to three
  secondary  clarifiers operated in parallel.   The clarified effluent is filtered
  as  a polishing step.   The filtered effluent  is  chlorinated  and dechlorinated
  and discharged via cascade  aeration tanks to the Little Patuxent River.

     The plant's effluent permit limits require a 30 day average BODs  of 20 mg/1
 from April through October and 30 mg/1 from November through March.   The 30 day
 average TSS  limit is  30 mg/1.    From April through  October  a 30 day  average
 total nitrogen limit of  10 mg/1 must be met.   The plant has  no total  nitrogen
 limit during  the  remainder  of  the  year,  however  total nitrogen is  reported.
 The plant  must  meet a  total phosphorus limit  of 1  mg/1  year  round.    Ferric
^chloride is added for phosphorus removal.

     Each of the  two total barrier oxidation  ditches  provided by Innova-Tech has
 a volume of 3.4 million  gallons.  The design hydraulic detention time of each
 is  approximately 27 hours at the average daily  flow.   Aeration in the oxidation
 ditches  is  supplied by positive  displacement blowers providing air to the draft
 tube aeration spargers.  Each secondary clarifier has a volume of 1.1 million
 gallons  resulting  in a  detention time of approximately 12 hours at design flow.
 The  clarifier  overflow rate  is 177 gpd/ft2 at average  design flow.

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                                                                        Page  3-15

      The  oxidation ditch  is  being operated  at a  MLSS  concentration of
.  approximately 1450 mg/1  and a mixed  liquor  volatile  suspended solids  (MLVSS)
  concentration of approximately  1000 mg/1.   The ditches  are being operated at an
,  SRT of approximately  15  days.   During the period  July 1990 through July  1991
  the plant operated at an average influent flow of 3.5 mgd, or approximately 58
  percent of design.  The average hydraulic detention time during the period was
  approximately 46.6 hours.  During the same period the influent BOD was between
  150 and  200  mg/1.   The BOD removal  was  greater  than 95 percent  during  the
  period.   The BOD loading during the period was 6.5 Ibs BOD/day/1000 cubic feet
  which was below  the design loading  of  13.8  Ibs BOD/day/1000 cubic feet.

      Chronological plots of the monthly average flow, NHs-N, total nitrogen,  and
  phosphorus are present  in Figure 9.  The oxidation ditches were  operated to
  achieve nitrification  and denitrification in  the  summer.   The long channel
  length  (1230 feet)  allows room  for an anoxic  zone.   Nitrification  and
  denitrification  were  occurring  in  the  oxidation  ditches  from April  through
  October  during the time  a  total  nitrogen permit  limit  had to be  met.   The
  average total nitrogen removal during  the summer months was 89 percent.  During
  the winter months only  one oxidation  ditch  is used  and  the  ditch is  not
  operated  to  achieve nitrification and denitrification.   The ditches  were  not
  designed for biological phosphorus removal.

     The  plant superintendent was  generally satisfied with  the operation  and
 performance of the  oxidation ditches.  Some problems were  experienced  with  the
 gear boxes for the draft tube mixers, however  that problem has been resolved.

 OTHER PLANTS PROVIDING DATA

 Cedarburg. Wisconsin

     The oxidation ditch at  the Cedarburg,  Wisconsin wastewater treatment plant
 is a  three channel Envirex Orbal system designed to treat  an average flow of
 2.75  mgc  and  a  peak  flow  of  8.0  mgd.    The  total volume  of the  ditch  is
 approximately 2.8  million gallons.    The  first channel has  a capacity  of  42
 percent of the total  volume,  the  second channel  33  percent,  and  the  third
 channel 25 percent

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                                         i i i  i i i |  i i ry ri i j n i | i i  r
                        July  1990 through  July 1991
           Figure 9. Chronological Plots of Monthly Average Data
                     Patuxent Water Reclamation Facility
                              Crofton, Maryland

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                                                                         Page  3-17
       The design detention time for the  oxidation  ditch at average design  flow is
   24 hours.   The  average  flow for the period January 1989  to  April 1991 was 54
   percent of the design flow,  and the  average detention time was approximately 45
   hours.
      The  plant was  designed  for a BOD  loading of 12.2  Ibs  BOD/day/1000 cubic
  feet.  During the period where data were available the  average BOD loading was
  5.5 Ibs  BOD/day/1000 cubic feet.   BOD removals during  the  period averaged 98
  percent.

      The  plant effluent  must meet  permit  limits of  2  mg/1 NH3-N during  the
  summer and 4 mg/1  during the  winter.   The  monthly  average  effluent  ammonia
  concentration during the period  of record  (1/89  to 4/91)  met the  permitted
  limits.   Ammonia  removals  averaged 99  percent for the period  of record.
  Influent and effluent total Kjeldahl nitrogen were measured once per month from
  August 1989  to April 1991.   The  influent concentration ranged from  10 to 90
  mg/1 and the effluent ranged  from 0.6  to  4 mg/1.   The average TKN  removal was
  95 percent.  Nitrate was  not  routinely measured.

      The plant effluent is required to meet an effluent phosphorus limit of 1.0
  mg/1.   Ferrous sulfate is added for  phosphorus removal.   The monthly effluent
  phosphorus  concentration  exceeded the permit  limit  in three of the 28 months
  that data were available.
 Dousman. Wisconsin
     The oxidation  ditch at the Dousman, Wisconsin wastewater  treatment plant,
 in operation  since 1982, is a  three  channel Envirex Orbal system  designed  to
-treat an  average flow  of 0.35 mgd and a peak  flow of 0.88  mgd.   The  total
 volume of the ditch is approximately 0.37 million gallons.

     The design detention time for the  oxidation ditch at average  design  flow  is
 24 hours.   The average flow for the period January 1989  to  December  1990 was  60
 percent  of design.   The  average detention time  during  that  period was
 approximately  43 hours.

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                                                                      Page 3-18

    The plant  was designed for  a BOD loading of  11.7 Ibs BOD/day/1000  cubic
feet.  During  the period when data were available the average BOD  loading was
6.4  lbs/day/1000  cubic feet.    BOD  removals during the  period averaged  97
percent.

    The  plant effluent  must  meet  permit  limits  of  2 mg/1  NHs-N during the
summer  and 4  mg/1 during the winter.   The  monthly  average effluent  ammonia
concentration  during the  period of record  (1/89  to  4/91)  met  the  permitted
limits.   Influent ammonia concentration is not measured.  TKN and  nitrate are
not measured.

    The  plant  does not have an effluent  phosphorus  limit in its  permit,
therefore  effluent phosphorus is not measured.

Dupape County. Illinois

    The  Dupage County,  Illinois,  Knollwood  Treatment Plant has  three  Innova-
Tech  total barrier oxidation ditches with draft tube  aerators.   The  plant was
designed  to  treat an average wastewater flow of 8.3 mgd and a peak flow of 24.7
mgd.  The  total volume of  each ditch is 2.33 million gallons.

    The  design detention  time for each oxidation ditch at average flow  is 20
hours.  At the average flow for the period January 1989 to May 1991,  which was
96 percent of  design,  the  detention time averaged  approximately 21 hours.

    The  plant was designed for  a  BOD  loading of 15.9  Ibs  BOD/day/1000   cubic
feet.   During the period  when data were available the average  BOD loading was
12.8  Ibs BOD/day/1000 cubic feet.  BOD  removals  during the period averaged 97
percent.

     The  oxidation ditch was designed for a MLSS concentration of 3500 mg/1 and
a. MLVSS  concentration of 2500  mg/1.  During  the period January 1989 to May 1991
the  overall average MLSS concentration was 2820 mg/1.

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                                                                        Page 3-19

      The plant  effluent  must  meet permit limits of 1.5 mg/1 NH3-N during summer
* and 4  mg/1  during  the  winter.    The  monthly average effluent  ammonia
  concentration  during  the  period of  record  (1/89 to  5/91) met  permit limits
? except  in  August and September  1990.   During those months  repairs  were being
  made to the aeration  system.   The overall  average effluent NH3-N concentration
  in  the both the summer  and winter was 0.57 mg/1.  The summer  average excludes
  the  two months (August  and September  1990) when  repairs were  made  to  the
  aerators.   The average  ammonia removal was 95 percent in  the both  the summer
  and winter.  TKN and nitrate are not routinely measured.

      The plant  does not  have  an effluent phosphorus limit and does not  measure
  phosphorus.

  Hanover. Pennsylvania

      The Hanover,  Pennsylvania  wastewater treatment  plant  has  two  oxidation
  ditches supplied with  Passavant brush rotors.   The plant was designed to treat
  an average  flow of 3.65 mgd and a  peak  dry  weather  flow of  5.58  mgd.   The
  volume  of  each ditch  is approximately 1.43 million gallons.  Approximately 30
  percent of  the  plant flow is  industrial.

      The design  detention  time  for  each  oxidation ditch  at average flow  is
  approximately  19 hours.   The  average flow  for the period  January  1989  to  May
  1991 was 105  percent of capacity.   The detention time during that period  was
  approximately 18 hours.

     The oxidation ditch was designed  for a MLSS concentration of  4000 mg/1  and
  a  MLVSS  concentration  of .2835 mg/1.   During the period January  1989  to April
  1991 the overall average MLSS concentration was 2932 mg/1.

     The design  BOD  loading to  the oxidation ditch was 12.1 Ibs  BOD/day/1000
 cubic feet.   The  average  loading  for the period of  record (1/89  to  5/91),
 assuming a 30 percent  BOD  removal in the primary settling tanks,  was 14.6 Ibs
 BOD/day'/lOOO cubic  feet.   The BOD removal in  the  oxidation ditch averaged 98
 percent.

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                                                                     Page 3-20

    The plant  effluent must meet permit  limits  of 1.5 mg/1  NH3-N during the
summer and 4.5 mg/1 during the rest of the year.  The monthly average effluent
ammonia concentration during the period of record (1/89  to  5/91) met the permit
limit for 21 of the 28 months.   Three of  the months during which permit limits
were exceeded were summer months.  The ammonia  removal during the summer was 94
percent and 86 percent during  the  rest of the  year.   TKN  and nitrate were not
routinely measured.

    The plant  must meet  an effluent phosphorus  limit  of 2.0  mg/1.   Ferrous
sulfate is added  for phosphorus removal.  The effluent concentration met the
phosphorus limit in 27 of the 28 months.   The average phosphorus removal was 82
percent.

Huntsville. Texas - Parker Creek Plant

    The Parker Creek wastewater treatment plant has two  Envirex  Orbal oxidation
ditches.  The  plant was  designed to treat an average dry  weather flow of 2.75
ngd and an average wet weather flow of 4.15  mgd.  The volume of each ditch is
approximately  0.723 mgd.   There are  three aeration  channels  surrounded by an
outside basin  that  is used as an  aerobic sludge digester.  The first channel
has a capacity of  approximately 52 percent of  the total volume,  the second
channel  approximately  31 percent,  and  the  third  channel approximately  17
percent.

    The design detention  time  for  each oxidation ditch at average dry weather
flow is approximately 12.6  hours.   At the average flow for the period January
1989  to April 1991,  which was 87  percent  of  the  design flow,  the average ,
detention time was approximately 14.5 hours.

    The  plant was  designed for  a  BOD loading of  approximately 39  Ibs
BOD/day/1000  cubic  feet of  aeration volume.    Influent BOD  data were  not
available, however  influent COD data were received.   Based on  an estimated
BOD/COD ratio  of  0.6, the average  BOD loading was 15.8 Ibs BOD/day/1000 cubic
feet.

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                                                                         Page 3-21

       The plant's discharge permit does not have  an NH3-N  limit, however influent
   and effluent  ammonia are  monitored.   The  monthly average effluent NH3-N
   concentration during the  period  of record (January 1989  to April 1991) was  less
,  than 1.0 mg/1  in 27  of  the 28  months.   The  average ammonia removal  was 97
   percent.   TKN and nitrate are not routinely  measured.   Data in manufacturer's
   literature indicated that  five samples were collected in June 1983 for effluent
   nitrate measurements.  The average of these samples was 3.6 mg/1.  The influent
   ammonia during  that  period averaged  24.7 mg/1 and the ammonia removal was 95.5
   percent.  These data  indicate denitrification occurred.

      The plant is not required to meet an effluent phosphorus limit and does not
  measure phosphorus.

  Huntsville.  Texas - South  Plant-

      The oxidation ditch at the South Plant  in Huntsville,  Texas is an Envirex
  Orbal system.   The plant  was  designed to treat  an  average  flow  of 1.6 mgd
  The  volume and  configuration of  each channel of  the  oxidation ditch were  not
  available.

      The  design BOD loading was not available.   The plant consistently met  the
  permit  BOD limit of  20 mg/1  during  the period of record.   The plant effluent
  permit  does not have an NH3-N limit, however  influent  and  effluent ammonia is
  monitored.  The monthly average  effluent NH3-N concentration was  less than 1
  mg/1  each  month for  the period of record (January 1989  to April  1991).   The
  average  ammonia  removal was  99 percent.   TKN and nitrate are not  routinely
 measured.

     The plant  is not required to meet an effluent phosphorus limit  and does not
 measure phosphorus.

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                                                                      Page 3-22
Kemraerer.  Wyoming
    The oxidation ditch at the Kemmerer, Wyoming wastewater treatment plant, in
operation since 1981,  is an  Eimco  Carrousel  system.   The plant was designed to
treat  an average  flow of 1.5  mgd.   The total  volume of  the ditch  is  1.43
million gallons.

    The  design detention time  for the oxidation  ditch at the  average design
flow is  approximately 23 hours.  The average flow for  the period January 1990
to June 1991 was 30 percent of the design flow.   The detention time during that
period was approximately 76 hours.

    The  design BOD loading  was not available.    The BOD  loading  to  the plant
during the period  of  record  was 3.7 Ibs BOD/day/1000 cubic feet.  BOD removals
during the period averaged 98 percent.
    The plant  effluent must meet an NHs-N permit  limit  of 3.8 mg/1 during the
summer.  There is no ammonia limit in the winter.  The monthly average effluent
ammonia concentration  for the summer months during  the  period of record (1/90
to 6/91) met the permit limits.  The average removal of ammonia was 98 percent.
TKN and nitrate are not routinely measured.                   ;

    The plant  does not have an effluent phosphorus  limit  and does not measure
phosphorus .

Lake Geneva. Wisconsin

    The  oxidation  ditch  at  the Lake  Geneva, Wisconsin  wastewater treatment
plant  is  a three  channel Envirex Orbal system using the  SIM-PRE mode.   This
mode of operation promotes denitrification.   The plant is designed to treat an
average flow of  1.74 mgd and a peak flow of 4.64 mgd.  The total volume of the
ditch  is approximately 1.1 million gallons.  During  the period December 1989 to
May  1991  the  internal MLSS recycle rate  from the  third  to  the first channel
ranged from 1.0  to 5.5 mgd.   This  system  recycles nitrified mixed liquor from
the third  channel  to the  first channel  for denitrification.

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                                                                          Page  3-23

s       The design  detention  time for  the oxidation ditch  at average flow  is
    approximately 15 hours.  The  average flow for the period  January 1989 to May
^   1991 was 63 percent  of design,  and  the average detention time was approximately
    24 hours.

        The oxidation ditch was designed for a MLSS  concentration of 4000 to 5000
    mg/1.   During   the period  of record (1/89  to 4/91)   the   average MLSS
    concentration was 5805 mg/1.  The MLVSS concentration averaged 4108 mg/1 during
    the  same period.

        The design  BOD load  to  the oxidation ditch  at average flow was  15.0  Ibs
    BOD/day/1000  cubic feet.  The average loading for the period of record (1/89 to
    5/91) was approximately 14 Ibs BOD/day/1000 cubic feet.

       The plant effluent  is discharged  to  seepage  cells for groundwater recharge
   and  must meet a  total nitrogen permit limit  of  10 mg/1 year round.   Effluent
   TKN and nitrate are measured daily.   The  effluent total nitrogen concentration
   was  less than the permit limit in each of the  29 months  (1/89 to 5/91) where
   data were available.   The influent  TKN and NH3-N are measured less  frequently
   than the effluent.  The average removal of total  nitrogen was 87  percent.

       The plant does  not  have  a  phosphorus  limit in  its  permit  and does not
   measure phosphorus.

   Lyons.  Wisconsin

      The oxidation ditch at  the  Sanitary  Sewer District No.   2 plant  in Lyons,
   Wisconsin  is  a Lakeside  oxidation  ditch.   The  ditch is designed  to treat  an
   average flow of  0.1 mgd.  The  total volume of the ditch is  approximately 0.13
   million gallons.
-*
      The  design detention time for the oxidation ditch at average design flow  is
   31.5  hours.  The  average flow  for the  period  January 1989  through May 1991 was
   74  percent of design.   The  average  detention  time during that period was
   approximately 42.5 hours.

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                                                                     Page 3-24

    The  plant  was  designed for  a BOD loading of  approximately  13  Ibs
BOD/day/1000  cubic  feet.    During the  period that  data were  available the
average BOD loading  was  8.2  Ibs  BOD/day/1000  cubic feet.   BOD removals during
the period averaged 97 percent.

    The plant must meet a permit  limit of weekly average NHs-N concentration of
3.0 ffig/1 from April  through October, and 6.0 mg/1 during the rest of the year.
The effluent NHs-N concentration  met the permitted limit during the period of
record (1/89 -5/91) .  Influent ammonia was not measured.  TKN and nitrate were
not measured.

    The plant  does  not  have a  phosphorus  limit in  its  permit and  does not
measure phosphorus.

jflorgan City. Louisiana

    The  three oxidation ditches  at the  Morgan  City,  Louisiana  wastewater
treatment  plant  are Eimco  Carrousel oxidation ditches with  an iriterchannel
clarifier.  The  system  is  designed to treat an average daily flow of 3.0 mgd.
The total volume of  each ditch is 1 million gallons, including the clarifier.
The volume  of the  ditch taken  up  by the  clarifier  was  not available.   The
average flow during  the  period January through  December 1990 was approximately
4 mgd which is approximately 133  percent  of design.

    The plant effluent must meet a monthly average  BOD permit limit of 30 mg/1.
During the period of record  (1/89  to  12/90) the monthly average concentrations
were below the permit limit every month.
    The plant  does not have  an NHs-N or total  nitrogen  limit in its permit,
however,  influent  and effluent  ammonia are  measured several  time  a month.
During the period of record the influent NHs-N concentration averaged  19.2 mg/1
and the effluent concentration averaged 0.35 mg/1.   The average ammonia removal
was 98 percent.  TKN, nitrate, and phosphorus were  not measured.

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                                                                      Page 3-25

Mount Clemens. Michigan

    The  oxidation ditch at  the Mount  Clemens,  Michigan wastewater  treatment
plant is a three channel Envirex Orbal system.   The oxidation ditch is designed
to  treat an  average  flow of  6.0 mgd.   The  total volume of  the  ditch  is
approximately  8.5  million gallons.   The first  channel has  a  capacity of  59
percent  of the  total volume,  the second channel  26 percent,  and the  third
channel 15 percent.

    The  design detention time  for the  oxidation ditch at  average flow is  34
hours.   The average  flow for the period January 1990 through June  1991 was  65
percent of design and the average detention  time was approximately 57  hours.

    The plant was designed for  an  average BOD loading of approximately 5.8 Ibs
BOD/day/1000  cubic  feet.  Influent and effluent  carbonaceous  BOD (CBOD) are
reported by the plant.   During  the period when data were available  the average
CBOD  loading  was 2.5  Ibs  CBOD/day/1000 cubic  feet.  CBOD  removal during the
period averaged 98 percent.

    The  plant effluent  must meet  permit  limits of 0.5  mg/1  NH3-N  from May
through September and  7.0 mg/1  NH3-N from October through November.   The plant
has  no  effluent  NH3-N limit during the rest  of  the  year.   The  plant
consistently met the permit limits  for  NH3-N.  The  average ammonia  removal was
98 percent.   Ammonia was not measured  during months when effluent limits did
not have to be met.

    The plant  effluent must meet  a phosphorus  limit of 1.0 mg/1 year round.
Chemicals were not added during the period  of  record,  however,  the plant does
have  a  ferric  chloride  feed system.    The  average effluent  phosphorus
concentration reported was 0.55 mg/1.   The  average phosphorus  removal was  78
percent.

Rehoboch Beach. Delaware

    The  two  oxidation ditches  at the Rehoboth  Beach,  Delaware  wastewater
treatment plant  are  Innova-tech oxidation  ditches with draft  tube  aerators.

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                                                                        Page 3-26

  Rehoboth Beach is  a  summer resort and the treatment plant was  designed for an
  average summer  flow of 3.4  mgd and an  average  winter flow of 1.0 mgd.   The
  total volume of each ditch is approximately 2 million gallons at average flow.

      The design detention time  for each oxidation ditch at average  summer  flow
  is approximately  29  hours.   The  average  summer flow  for 1989  and 1990  was
  approximately 1.4 mgd  or  41 percent of  design.   The  average  winter flow  for
  1989,  1990,  and the first three months of 1991 averaged approximately 0.68  mgd
  or 68  percent of design.

     The plant effluent  must meet a monthly average BOD permit'limit  of 19 mg/1.
  During the period  January 1989 to April 1991 the  plant  effluent  was  within
  permit limits.  The plant also must meet a monthly average total nitrogen limit
  of 3 mg/1  from April  through September.   The effluent TKN concentration ranged
  from 0.47  to  7.98 mg/1 during the  summer months of  1989 and 1990.   An average
  TKN  reduction of 89  percent was achieved  during  the  summer  months.   The
  effluent N03-N concentration  ranged  from 0.13 to 18.5 mg/1  during the  same
 period.  An average 54 percent reduction in total  nitrogen was  reported for the
 summer period.   The monthly average effluent total nitrogen concentration  was
 greater than the 3 mg/1 plant limit during all the summer months.

     The plant does not have an effluent  phosphorus  limit in its  permit and does
 not routinely measure phosphorus.

 Hanaque. New Jersey

     The two oxidation ditches which operate in parallel, at the Wanaque Valley
 Regional Sewage Authority wastewater treatment plant in Wanaque, New  Jersey are
 Eimco Carrousel oxidation ditches.   The  plant was  designed to treat  an average
 daily flow  of 0.7 mgd.  The total volume of  each  ditch is approximately 0.43
 million gallons.

    The  design detention time for  each oxidation ditch  at  average design flow
 is  approximately 29.5 hours.   The average  flow for the period November 1989 to
February 1991  was 104 percent of  design.   The average detention time  during
that period was approximately 28 hours.

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                                                                      Page 3-27

    The plant  was designed  for  a BOD loading  of 12.7 Ibs  BOD/day/1000 cubic
feet.   During the  period  of  record  the average  BOD  loading  was 8.2  Ibs
BOD/day/1000 cubic  feet.   BOD removals  during  the period averaged 98 percent
and the effluent consistently met the 8 mg/1 permit limit.

    The plant  must  meet  an effluent  permit limit  of 2.2  mg/1 TKN  from  May
through October.   The  monthly  average  effluent  TKN concentration  during  the
period of  record (November 1989  to  February  1991) met the  permit limit every
month.  The  average TKN removal  was 97  percent both in  the summer and during
the rest  of the  year.   Influent  and  effluent  NH3-N  are also measured.   The
average NH3-N  removal  in the summer was 99 percent and  98  percent during  the
rest of the year.

    The plant  must  meet an  effluent phosphorus limit of 1.0 mg/1 year round.
Alum is added for phosphorus removal.  The average removal of phosphorus was 83
percent.

Gwinnette County. Georgia

    The four parallel  oxidation  ditches at the Yellow River/Sweetwatef Creek
Reclamation Facility in Gwinnette County,  Georgia,  are  three  channel Envirex
Orbal oxidation ditches.  A plant expansion was  completed in June 1989 to treat
an average design flow of 12 mgd.   The volume  of each ditch is approximately
1.4 million gallons.  Three of the four oxidation ditches are currently in use.
An internal  recycle from  the  third channel  to the  first  channel is used to
promote denitrification.

    The design detention time  for each  oxidation ditch  at  the  average  design
flow was  approximately 11.4 hours.   The  average  flow for  the  period January
1989 through December  1990 was  47 percent of design  and  the average detention
time was approximately 18.5 hours.

    The plant  was constructed with four  primary clarifiers,  however,  they were
not in use during the  period of  record.   The  plant must meet a monthly average
effluent BOD concentration of 5.0  mg/1.   During the  period of record the plant
consistently met this limit.

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                                                                       Page  3-28

     The  plant must meet permit limits of 1 mg/1 NH3-N and 6.0 mg/1 N03-N.  The
monthly  average NH3-N concentrations were less than 1.0 mg/1 for each  of the 24
nonths of record.   The average NH3-N removal was  98  percent.   N03-N data were
available  for the  period  April 1990 through June 1991.   The  monthly average
N03-N concentration was less than 5.0 mg/1 for each of the 15 months.

    The  plant must meet an  effluent  phosphorus limit of  0.5  mg/1.   Alum  was
added for phosphorus removal.  The average phosphorus  removal was 99 percent.

-------
                                                                       Page 4-1
                                  SECTION 4.
                             OXIDATION DITCH COSTS
CAPITAL COSTS
    <
    Construction  costs  were available for ten plants.   The construction costs
are  for the entire plant  but do not  include  land costs.   Capital costs were
estimated  from construction  costs by  adding 15  percent for  engineering and
construction supervision and  15 percent for contingencies.   All capital costs
were  adjusted  to  July  1991 costs  using the ENR construction cost index 4854.
The adjusted capital costs for the ten plants, their design flow, and costs per
gallon  per day  are presented  in -Table  5.    The  costs  ranged from  $1.61  to
$9.99/gpd.   The  costs  for the two plants  designed for  denitrification,  Lake
Geneva, Wisconsin, and  Patuxent Water Reclamation Facility in Crofton, Maryland
were  $8.44  and $6.28/gpd,  respectively.   These costs are  in the same range as
the  eight  plants not  designed for  denitrification.    Figure 10  presents  the
adjusted capital costs for the ten plants.

                            TABLE 5.   CAPITAL COSTS
Facilitv
Cedarburg, WI
Dousman , WI
Dupage County, IL
(Knollwood Plant)
Hanover , PA
Huntsville, TX
(Parker Creek)
Huntsville, TX
(South Plant
Lake Geneva, WIa
Morgan City, LA
Patuxent, MDa
Rehoboth Beach, DE
aDesigned for denitrification
Adjusted
Capital Costs
Julv 1991 (SI
8,238,588
3,464,424
34,526,123
14,321,834
6,911,766
2,574,969
14,691,967
10.284,377
37,702,014
22,914,934

Design
Flow
(mgd)
2.75
0.35
8.3
3.65
2.75
1.6
1.74
4.50
6.0
3.4

$/gpd
2.99
9.99
4.16
3.92
2.51
1.61
8.44
2.29
6.28
6.74


-------
       100-
              I    I  I I  I I 111     I   I  I  I I I 111


          "X DESIGNED FOR DENITHIFICATION
1   I  I I  I I II
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<
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              I   I  I  I  I 11II	I   I  I  I I 11II     I   I  I  I I III
        0.1
                                           10
                                                            100
                          DESIGN FLOW  (mgd)
                      Figure 10.  Capital Costs

-------
                                                                       Page 4-3

 OPERATION AND MAINTENANCE COSTS

    Overall operating  costs  for eight  plants were  available.    These costs
 include all  costs to  operate  the  wastewater treatment  plants  in  the year
 indicated.   Utility costs,  which includes electricity,  telephone,  and gas for
 the  entire  wastewater treatment  plant were available  for  seven plants.   The
 costs for two plants  are the projected 1991 budget.   The design flow, average
 flow during the period of record, year, the operating costs, utility costs, and
 costs per gallon per day at the average flow  are  presented in Table 6.   The
 operating costs per gallon per day ranged from $0.14 to $1.00/gpd.   The utility
 costs per gallon per  day at  the  average  flow ranged from  $0.04 to  $0.16/gpd.
 It should be noted that operating and utility  costs vary with plant  location
within  the  United States.    The relationship  between actual  plant  flow  and
overall operating costs and utility costs  are presented in Figure 11.

-------

























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       0.01               0.1                1
                      AVERAGE PLANT  FLOW  (mgd)
            Figure 11.  Operating and Utility Costs

-------

-------
                                                                       Page 5-1
                                   SECTION 5.
                                   REFERENCES

 1.  Ettlich, William F. ,  A Comparison of Oxidation Ditch  Plants  to  Competing
     Processes for  Secondary  and Advanced Treatment of Municipal  Wastes,  EPA-
     600/2-78-051,  U.S.  EPA,    Wastewater  Research Division, Municipal
     Environmental Research Laboratory, Cincinnati, Ohio, March 1978.

 2.  Process Design Manual for Nitrogen Control.   U.S.  Environmental Protection
     Agency, October 1975.

 3.  Process Design Manual for  Phosphorus Removal.    EPA/625/1-87/001,  U.S.
     Environmental  Protection  Agency,  Center  for  Environmental  Research
     Information, Water Engineering Research Laboratory,  Cincinnati, Ohio, 1978.

 4.   Eimco  Process  Equipment  Company,  Eimco Carrousel Biological Oxidation
     System,  Excellence in Biological Treatment, 1986.

 5.   Riser,  Fredrick M. ,  Nutrient Removal  from Wastewater Using  the  Carrousel
     Oxidation Ditch System with the Modified Bardenpho  Process,  Presented at
     the New Jersey Water Pollution Control Association Meeting, May 1990.

 6.   Eimco  Process  Equipment  Company, Bardenpho  Process Biological  Nutrient
    Removal System, 1984.

7.  Envirex, Orbal Aeration System  Product  Book for Envirex Field Force Offices
    and Representatives, August 1989.

8.  Envirex, The  Orbal  System for  Flexible  Efficient Biological Treatment,
    1988.

-------
                                                                    Page 5-2
9.  Innova-tech,  Inc.,  The Total  Barrier  Oxidation  Ditch System. Equipment
    information received June 1991.

10. Berk,  William  L. ,  Things You  Should Know  About  the Lakeside Oxidation
    Ditch, Lakeside Equipment Corporation, RAD-603, November 1984.

11. Lakeside Equipment  Corporation,  Equipment information  and  design
    information.

-------
                            APPENDIX A

 Monthly Average Tables and Chronological Plots for Wastewater
 Treatment Plants Providing Data
 Cedarburg, WI
 Dousman, WI
 DuPage County, IL (Knollwood Plant)
 Hanover, PA
 Huntsville, TX (Parker Creek and South Plant)
 Kemmerer, WY
 Lake Geneva, WI
 Lyons, WI
 Morgan City, LA
 Mt. Clemens, MI
 Rehoboth Beach, DE
Wanaque, NJ
Yellow River/Sweetwater Creek Water Reclamation Facility,
Gwmnette County, GA

-------

-------
Cedarburg, Wisconsin UUTP -  Monthly Average Data.
Date
 QQ
lo9
289
389
^489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
Flow
1.141
1.072
1.277
1.174
1.146
1.467
1.381
1.643
1.578
1.178
1.144
1.034
1.333
1.291
1.898
1.772
2.425
1.708
1.407
1.392
1.393
1.320
1.412
1.663
1.385
1.442
1.948
2.621
Influent Effluent
BOO BOD
(mg/L) (mg/L)
196.4
215.9
165.3
158.3
186.8
143.5
152.2
129.1
144.6
186.7
217.9
227.7
188.2
186.5
162.4
141.7
111.3
133.1
148.6
181.1
177.7
181.1
158.0
152.8
188.7
168.1
133.8
93.9
5.53
5.46
7.00
5.67
6.14
4.60
3.77
2.77
3.20
3.10
3.33
3.39
4.10
3.86
3.74
5.41
2.77
2.65
2.62
2.32
2.57
2.26
2.15
2.03
3.29
2.48
2.74
3.55
Influent Effluent
TSS TSS
(mg/L) (mg/L)
168.9
165.8
146.9
153.4
159.1
136.5
151.6
124.8
130.9
157.5
167.9
176.2
188.2
134.3
122.3
122.3
108.7
125.7
147.6
181.0
166.7
181.4
143.8
127.8
156.8
147.1
117.4
89.8
4.10
3.54
4.68
4.03
4.61
3.03
2.87
2.45
4.67
3.71'
3.60
2.68
2.97
2.43
2.71
2.38
2.58
3.03
2.35
3.13
3.50
3.35
2.27
1.97
3.39
2.93
2.39
2.67
Influent Effluent Influent Effluent
P" PH TKN TKN
(mg/L) (rog/L) 
2.5
1
0.6
1.1
1.1
1
0.9
0.94
1.2
1.1
1.3
1.6
0.99
0.67
0.97
1.1
0.72
1.5
0.96
Influent
NH3-H
(mg/L)
25.80
18.05
19.33
15.10
13.62
13.53
15.50
9.58
.10.17
14.00
18.20
20.40
17.96
16.62
12.87
11.60
7.85
11.92
13.86
16.10
16.92
17.48
17.10
15.23
16.77
15.08
11.72
8.05
Effluent
NH3-N
(mg/L)
0.127
0.034
0.331
0.043
0.032
0.035
0.031
0.031
0.030
0.030
0.030
0.112
0.030
0.030
0.030
0.034
0.030
0.031
0.030
0.030
0.038
0.033
0.031
0.036
0.030
0.031
0.030
0.031
Effluent
Total P
(mg/L)
0.602
0.643
0.589
0.765
0.654
0.728
0.698
0.554
0.913
2.520
1.100
0.415
0.560
0.547
0.994
0.620
0.699
0.824
0.574
1.032
0.530
0.813
0.236
0.311
0.502
0.373
0.393
0.649
Hydraulic
Sludge Detention
Age Time
(Days) (Days)
293 "
59.5
60.2
63.1
55.4
53.8
55.3
29.1
34.9
36.6
34.8
36.3
30.4
30.1
30.8
30.4
30.1
21.9
21.8
20.6
18.5
21.0
18.5
16.8
18.7
19.8
17.7
14.4
2.5
2.6
2.2
2.4
2.5
1.92 '
2.04
1.7
1.8
2.4
2.5
2.7
2.1
2.2
1.5
1.6
2.1
1.6
2
2
2
2.1
2
1.7
2
1.95
1.4
.1.1

-------
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        4.00
        3.00 _
        a.oo _
        .00-
                                      Cedarburg.   Wisconsin
        o.oo
            JFMAMJJASONDJFMAMJJASONDdFMA
         300
         200
100
            _A influent
              o Effluent
                                                             Effluent BOD  Limit - 10.0 mg/L
             iTi lAl I KJ)l I lAl I lAl I lAl I lilil I lAl I llI till I lAl I lAl I idil I lilil I idil I Irlil I ijil I Ifil Mff114
            JFMAMJJASONDJFMAMJJAS'ONDJFMA
         300
         200
         100
                                                             Effluent  TSS Limit - 15.0  mg/L
             7. ill  iii i ill i ill i ill i ili i ili i ilt i ill i iL i ill i ill i iii i ili i ili i ill i ill i ill i ill i ili i ill i ill i ili i ill i ill i ili 11.
            JFMAMJJASONDJFMAMJJASONDJFMA

                              January  1989 through  April  1991

-------
O)
 I
CD
X
          100
                                        Cedarburg,   Wisconsin
          so
          60
                Hi  1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Mill
                _  '   '   '   '   .....   'Mo'nthiy  AVerWes1   !   '
                -A Influent
                -o Effluent
 O)   .
          20
                                                                         1 1 1
|m|iii|ui[nT[TiL
             n 1111111 M 111111111111111 i^fmij-iiLij ill j tL i iJ>i i i/li i ill i ill i i/ii' 'li i i-l-i 11-^1' 'ii i ill 11Jj iiii i ill i iJsi i ill IT
            JFMAMJJASONDJFMAMJJASONDJFMA
          100
          80
          60
          40
                                                       Summer  Effluent  NH3-N Limit  - 2.0
                                                       Winter  Effluent  NH3-N Limit  - 4.0 mg/fc-
            JFMAMJJASONDJFMAMJJASONDJFMA
        5.00
   (0


C _.-^
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             JJI|lll|lll|lll|lll|lll|lll|lll|lll|lll|lll|lll|lll|lll|lll|!ll|lli|lll|lll|lll|lll|lll|lll|lll|l||||||||ll

                                                         Effluent Phosphorus Limit =1.0 mg/k-
        4.00
        3.00
  '~'    2.00
        1.00
        n nnrnilllllllllllllllilinlllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
            JFMAMJJASONDJFMAMJJASONDJFMA

                               January  1989  through  April  1991

-------
        9.00
                                 Cedarburg.  Wisconsin
           -A Influent
             o Effluent
       8.00
 (0
 X
 Q.
       7.00
       6.00
                                     Mo'nthi
Effluent pH Limit is between 6.0 and 9.0-
          JFHAMJJASONDJFMAMJJASONDJFMA
        100
        80 _
 CD
03
D)
(U
O>
T3
03
         JFMAMJJASONDJFMAMJJASONDJFMA

                         January  1989  through April  1991

-------
Dousman, Wisconsin WWTP - Monthly Average Data.
Date
189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
Flow Influent Effluent Effluent Effluent
HGO BOO BOD TSS NH3-H

0.192
0.196
0.204
0.194
0.188
0.18
0.181
0.205
0.239
0.188
0.206
0.201
0.206
0.203
0.205
0.21
0.262
0.24
0.216
0.231
0.221
0.211
0.223
0.21




179
178
207
198
156
172
195
196
199
245
196
202
205
184
173
147
155
173
184
171
183
171
155
178




6
7
6
6
6
5
6
6
6
6
6
6
7
6
6
6
6
6
6
5
6
6
6
6




<4
5
<4
<4
<4
<4
<4
<4
<4
<4
<4
<4
5
4
4
4
4
4
3
2
2
3
2
3




2.56
1.3
0.5
0.61
0.56
0.8
0.89
0.7
0.71
"0.55
0.75
1.51
1.56
1.4
1.16
1.32
0.94
0.35
0.29
0.22
0.5
1.18
1.22
1.52
1.91
2.05
1.86
0.91

-------
 Q
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        0.30
0.20.
0.10
        0.00
                                                     rm
Dousman.  Wisconsin
      lljiil|iil|lll|
   Mo'nthly Aver


      - Q  o  o-
           JFMAMJJASONDJFMAMJJASONDJFMA
         300
         200 _
               Influent
             o Effluent
                                          Summer Effluent BOD Limit - 10.0 mg/L
                                          Winter Effluent BOD Limit - 20.0 mg/C
 100 _
           JFMAMJJASONDJFMAMJJASONDJFMA
10.0



 8.0



 6.0



 4.



 2.0



 0.0
                  -eeo oeeee-
                                                  Summer Effluent TSS Limit    10.0 mg/tr
                                                  Winter Effluent TSS Limit  -  20.0 mg/C
                                                 Q  o  o
           JFMAMJJASONDJFMAMJJASONDJFMA
       3.00
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       2.00
       1.00
       o.ooEi
                                                 Summer Effluent NH3-N Limit - 2.0 mg/C
                                                 Winter Effluent NH3-N Limit =4.0 mg/C
          JFMAMJJASONDJFMAMJJASONDJFMA

                            January 1989  through  April  1991

-------
                              DuPage County, Illinois WWTP -  Monthly Average Data


Date

189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
591


Flow
(MOD)
5.860
4.449
7.083
5.705
5.504
7.157
6.832
6.850
7.566
5.954
6.264
4.885
7.556
8.348
9.672
8.152
12.145
9.271
10.235
9.392
7.972
9.856
9.438
9.001
7.519
8.257
11.108
11.179
9.469

Influent
BOO
(mg/L)
158.0
204.8
142.5
257.0
224.7
196.9
241.3
180.0
113.6
156.6
170.8
253.4
214.9
142.2
238.7
203.5
187.3
236.9
279.0
271.4
224.9
181.3
165.7
155.1
262.7
100.8
156.3
80.5
95.1

Effluent
BOO
(tng/D
7.3
2.6
3.7
5.3
7.7
11.5
3.9
1.6
1.4
2.9
2.3
2.4
4.6
3.2
3.8
2.3
7.1
2.3
3
5.9
7
16
10.6
2.4
2
2.7
11.1
6.4
5.3

Influent
TSS
(rag/L>
163.4
185.9
138.7
362.1
267.8
339.8
480.3
386.8
157.8
307.8
241.9
254.0
379.3
187.4
465.6
303.2
318.1
202.7
280.7
419.5
339.8
304.9
231.5
143.1
450.2
112.0
282.3
113.9
137.2

Effluent
TSS
(mg/L)
12.3
2.4
3.9
3.8
5.1
29.3
9.3
3.3
3.7
 5.3
5.2
3.6
9.2
5.3
6.4
4.3
16.2
2.1
4.6
8.1
4.3
53.9
39.5
3.4
3.3
4.6
61.9
40
30.2

Influent
pH
(mg/L)
7.9
7.9
7.9
7.8
7.7
7.8
7.8
8.0
7.9
7.9
7.9
7.9
7.7
7.5
7.5
7.4
7.5
7.5
7.5
7.4
7.4
7.5
7.6
7.6
7.5
7.6
7.7
7.7
7.6

Effluent
PH
(mg/L)
7.9
8.0
7.9
7.9
7.9
7.9
7.8
8.0
8.0
7.8
8.0
8.1
7.7
7.5
7.5
7.4
7.4
7.6
7.5
7.6
7.5
7.7
7.7
7.5
7.5
7.4
7.5
7.5
7.5

Influent
NH3-N
(mg/L)
13.5
16.4
10.1
13.2
14.5
13.7
13.7
10.9
9.7
16.3
12.9
16.4
12.0
10.9
8.8
11.3
8.1
12.1
11.4
12.7
16.0
14.0
12.7
11.2
13.1
11.4
8.9
8.6
9.2

Effluent
NH3-N
(mg/L)
0.7
0.2
<0.1
0.3
0.7
0.6
0.4
<0.1
0.2
2.6
<0.2
0.6
1.5
0.4
1.3
0.3
0.2
0.3
0.4
3.4
3.9
0.3
0.6
0.3
0.8
0.5
0.2
0.4
0.5
Mean HLSS
of the 3
Reactors
(mg/L)
2398
2544
2906
2917
2711
2343
2407
2863
2943
2839
2529
2430
2824
2832
2502
3411
2879
3118
3136
3624
3657
3366
3058
2495
2353
2880
2715
2452
2671
Note: High TSS in October,  November 1990,  March, April and May  1991  are
      due to heavy rains.
      Aeration system repairs  in August  and September 1990.

-------
 O)
2

m
x
Q.
         100
                                DuPage County.   Illinois
           _A influent
             o Effluent
         80
         60
         40
         20
                           onthly Averages
                                  Summer Effluent NH3-N Limit =2.0 mg/L
                                  Winter Effluent NH3-N Limit - 4.0 mg/C
            'idiii^mliidndiMJjM^iii^if^
          OFMAMJJASONDJFMAMJJASONDJFMAM
       10.0
        9.0
        7.0
        6.0
 a  Influent
o  Effluent
                                            Effluent pH Limit is between 6.5 and 9.0
          JFMAMJJASONDJFMAMJJASOND.  JFMAM

                           January  1989 through May  1991

-------
        15.0
                              DuPage  County.   Illinois
 en
a
o
m
O>
en
en
        O.Oi
          JFMAMJJASONDJFMAMJJASONDJFMAM
        300
        200 _
                                                   Eftflu^it BOD Limit a 80.0 mg/L
100 _
          JFMAMJJASONDJFMAMJJASONDJFMAM
        500
        400 _
       300 _
                                                   Effluent TSS Limit * 85.0
       200 _
       100 _
          JFMAMJJASONDJFMAMJJASONDJFMAM


                          January  1989 through May  1991

-------
Hanover, Pennsylvania WWTP - Monthly Average Data.
Date
189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
Influent Effluent Influent Effluent Influent Effluent Influent Effluent
Flow BOO BOD fSS TSS NH4N NH4N TP TP
(HCO) Cog/L) (mg/L) (mg/L) (mg/L) (mg/L) (ing/L) (mg/L) (mg/L)
2.950
2.777
3.491
3.877
7.029
5.036
4.727
4.406
4.256
5.020
5.306
3.395
3.816
3.634
3.095
3.412
3.900
3.206
3.107
3.246
2.537
3.604
3.047
3.855
4.639
3.075
3.369
3.153
287.6
330.0
294.9
281.1
181.9
231.5
217.1
265.5
284.0
277.8
220.9
337.3
251.1
250.0
250.0
258.0
224.0
231.0
248.0
240.0
307.0
255.0
255.0
208.0
147.0
184.0
191.0
223.0
5.0
5.9
7.0
3.8
15.0
3.9
6.0
5.3
5.3
3.3
5.9
7.5
11.7
6.5
6.2
5.8
12.1
5.4
3.9
6.3
4.0
7.5
3.0
8.6
13.5
2.2
2.0
2.9
171.6
178.0
150.5
205.0
152.8
209.3
217.0
338.4
304.5
370.7
333.4
329.0
274.9
250.0
248.0
237.0
243.0
227.0
247.0
238.0
274.0
273.0
252.0
175.0
148.0
236.0
214.0
272.0
3.3
4.7
5.0
3.3
14.0
2.9
7.2
3.5
3.3
2.3
5.0
2.7
6.0
2.9
2.9
1.5
4.6
1.7
4.0
2.7
2.5
5.3
1.4
3.3
10.4
1.0
1.6
1.3
20.2
23.2
16.5
18.8
10.5
14.1
16.5
19.9
24.7 ,
19.9
19.4
25.8
16.1
15.3
19.4
17.7
13.1
16.4
20.4
14.6
20.8
14.6
17.2
12.7
8.9
13.7
11.7
12.5
2.2
8.7
2.4
1.8
4.7
0.5
0.4
0.7
0.9
0.6
1.9
1.5
1.3
0.8
1.1
0.5
1.3
1.0 '
0.9
2.4
2.0
1.6
0.8
5.7
13.1
1.0
1.1
0.2
7.2
8.1
7.4
9.4
5.2
8.5
7.3
9.6
9.4
8.5
7.5
10.5
7.0
7.0
8.3
7.6
7.8
6.8
7.5
7.1
8.4
6.8
7.0
5.3
4.7
8.0
8.0
8.3
1.9
1.9
2.1
0.9
1.2
1.3
1.3
0.9
1.2
0.8
0.7
0.8
0.7
1.1
1.5
1.5
1.1
1.5
2.0
1.5
2.0
1.9
0.9
1.2
1.4
1.9
1.5
1.3
HLSS
(mg/L)













3171
2495
2497
3065
2726
2179
2769
2229
3159
4043
4028
3458
3117
2669
2382

-------
  O
  (S3
 0)

 E
 a
 o
 m
O)

E
         10.0
         8.0
6.0
         4.0
         2.0
                                   Hanover.  Pennsylvania
         o.olllllllllllllllllilililililililil, l.l.l.l.l.hhhl.hhl.l.lil
           JFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFM
         500
        400
        300
        200
        100
           -A influent
           -o Effluent
              I'lUiI'MI'MMI'I'I'MMM
                            I'l'I'IM'MI'I'lUJJ'I'J'lU'l'J'J'I'I'J'J'I'i
                                           Effluent'BOD'Limit'-'l2.0 mg/l
                                             ^hMuUU^AMU.t^^^44^j
          JFMAMJJASONDJFMAMJJASON DJFMAMJJASONDJFMA
        400
           -U'lM'I'MI'I'MHIH'MHMM
        300
        200
        100 _
                             I'l'I'I'I'I'I'lU'l'I'I'IMiliJiJililijiiiiii
                                     A    EfflUerit'TSS'Limit'-'30.0 Ag/
         QlTl 1111 111 111 I h 11 I 11
          JFMAMJJASONDJFMAMJJASONDJFMA fTj J A S 0 N D J F M A


                         January  1988  through  April  1991

-------
  \
  O)
  X
  O)
  
CO tfi
p a
o c.
H o
  jr
  o.
  en
  o
        30.0
        25.0-
        20.0 _
         15.0
         10.0 _
                                   Hanover.  Pennsylvania
                                    Mill UNI |IJMI Mill l|l|l
                                    1  Monthly1 Averages '
                                            Effluent NH3-N Limit  (Summer) -1.5 mg/tr
                                            Effluent NH3-N Limit  (Winter) =4.5 mg/t
   UM'MlM'I'lMMMM
              FMAMJJASONDJFM-AMJJASONDJFMAMJJASONDJFMA
         20.0
         15.0
10.0
          5.0
          O.i
                                                 Effluent Phosphorus Limit = 2.0 mg/L
                  hlii.I.Itl.ill	iTihhliTiliTi
            JFMAMJJASONDJFMAMJJASONDJFMAMJJASONDJFMA


                            January 1988 through April  1991

-------
CD
Q
O
CJ
       25.0
                          Huntsville.  Texas -  Parker  Creek Plant
           111 111  111  111 111  111  MI 111 MI  111 111 111  111 111 m m 111 111 111  111  111 111 111  111  111 11 Mill
           - i   '   i   '  i   i   '     i   'Mo'ntniy AWages1  '   '   '   '  '   '   '   '  '  -
           _A  Influent
             o  Effluent
       20.0
       15.0
       10.0
        5.0
          JFMAMJJASONOJFMAMJJASONDJFMA
        500
        400 _
        300 _
                                                      fh~ O  O G>     ^^^"r       ^^ ^
                                                      niTiiiTiiiTiiiliiiliitTniliiiliiilnil
200 _
        100 _
          JFMAMJJASONDJFMAMJJASONDJFMA

                           January  1989  through April  1991

-------
HuntsvUle, Texas - Monthly Average Data
Parker Creek UWTP

Date

189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491

Flow
HGO
3.500
2.500
2.470
2.170
2.200
2.200
1.900
2.120
2.360
2.370
2.210
2.140
1.800
1.940
1.820
1.840
2.280
1.590
1.820
2.060
2.580
3.260
2.470
2.800
4.130
2.740
2.490
2.850
EFF
BOO

-------
       25.0
                              Huntsville.  Texas - South Plant
O)
a
o
o
       20.0_
       15.0 _
O)
23     10.o_
                              II! Ill  III III MM III III III III  III III III  III

                                1   '  'Mo'ntfilvl AVeiWes1  '   '
           _ A  influent
             o  Effluent
          JFMAMJJASONDJFMAMJJASONDJFMA
        500
        400
           11111111111111111111111111111111111111111111111111111111111111111111II1111111111111111111111111111111111111
        300
200
        100
           11 m i HI i in 111 n 1111 iTi i ill i iTi i ill
          JFMAMJJASONDJFMAMJJASONDJFMA


                           January  1989  through .April  1991

-------
        6.00
        5.00
 ~     4.00
 Q
 CD
                               Huntsville,  Texas  - South  Plant
 3:
 o
 D)
 E
O
O
CD
 C
 03
 =J
CO
4J

(U
*-
4-
Hl
        3.00
        2.00
                                        Monthi
           JFMAMJJASONDJFMAMJJASONDJFM
        50.0
        30.0
        20.0
        10.0
                                                        Effldent BOD Limit =  10.0 mfl/l_
           JFMAMJJASONDJFMAMJJASONDJFMA
       50.0
           TJTJTT
       40.0
       30.0
       20.0
       10.0-
                                                        Eident TSs  imit - iS.  md/l_
        o.otmilLL

          JFMAMJJASONDJFMAMJJASONDJFMA

                           January  1989 through  April  1991

-------
Huntsville, Texas - Monthly Average Data

Date
189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491

Flow
30 Day 3
HGO (
0.950
0.950
0.820
0.860
0.810
1.000
0.940
0.880
.060
.000
.030
.140
.180
.110
.030
.030
0.950
0.900
0.930
0.940
1.040
0.980
0.940
0.980
1.190
1.110
0.940
1.100

BOO
0 Day
mg/L)
2.6
1.8
2.7
2.9
3.3
2.2
2.3
7.6
2.1
2.2
1.9
2.4
4.3
3.4
3.2
2.0
3.2
4.9
2.2
1.9
2.6
2.5
2.0
3.2
3.7
2.5
1.7
2.7
South UUTP
Raw
COO
234.8
253.2
237.4
299
286.4
201.8
227.9
258.2
268.2
262.5
284.2
421
273.2
220.8
237.2
248.58
256.7
214.3
208.9
315.6
274.7
320
276
343.8
331.2
277.6
334.3
333.7

Final
COO

-------
  3:
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 4J
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-------
  a
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CO
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 0.80




 0.6C




0.40




0.20
C3)
                                       Kemmeren.  Wyoming
                                        Mot
nln'^"^^'''"''"'"'!'"!'"!!!!!
                                              o   o
                   I I I I I  I IM 11i i IiM I , ,, I  M . I.., I , , , I,,,  ,..  , , 1,, ,  ,, ,  . . .  . .

            JFMAMJJASONDJFM
                                                                           A    M   J
         300
             A Influent
             o Effluent
         200
100
                                      111  '" I 'J!'  I'' M 1111111111II111111
                                               Effluent! BOo'Limi't = 30.0 U/
                                      ig/C
        500
                                                       I I M I I   I |

                                                       Effluent TSS'Limi't
                       A   M   J    J    A
                  MAMJJASNDJFMAMJ

                           January  1990  through  June  1991

-------
     Kenroerer,  Wyoming  UWTP  -  Monthly Average Data
               INF    EFF    INF    EFF    INF    EFF
Date   Flow    BOO    BOO    TSS    TSS   NH3-N   NH3-N
       (HGO) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L>  (mg/L>
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
591
691
0.567
0.560
0.502
0.463
0.446
0.445
0.413

0.402
0.412
0.355
0.418
0.467
0.499
0.574
0.392
0.389
0.417
176
168
203
163
183
202
188
187
199
198
200
259
192
179
161
179
178
158
4.18
5.10
3.58
3.83
4.19
3.11
3.67
1.99
2.12
1.94
2.23
3.89
7.39
8.42
4.15
3.39
2.80
2.20
258
203
354
262
223
242
238
339
296
343
288
326
293
223
243
259
433
334
6.80
8.00
4.25
6.70
6.80
5,30
9.10
4.40
5.00
4.60
3.80
5.70
5.20
6.60
3.60
4.40
3.50
3.10
16.05
15.51
16.89
18.57
18.82
19.38
15.24
17.68
19.41
17.86
20.75
16.38
17.22
15.74
15.08
18.29
16.61
15.14
0.414
0.376
0.102
0.065
0.132
0.078
0.121
' 0.084
0.073
0.072
0.075
0.517
1.073
0.794
0.333
0.092
0.094
0.075

-------
        3.00
 a
 CD
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        i.oo
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       o.ooi
                               Lake Geneva.  Wisconsin
          
-------
Lake Geneva, Wisconsin UUTP -  Monthly Average Data
Influent Effluent Influent Effluent Influent Effluent Influent Effluent Influent Effluent Influent Effluent
OHe FtOW iOO BOO TSS TSS TKN TKN NH3 NH3 TN TN N03 N03 HLSS
 (mg/L) (mg/L) (mg/L) (mg/L)  (mg/L)
169
289
349
<89
SS9
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
591
0.75
0.75
0.80
0.76
0.79
0.80
0.77
1.10
1.09
1.25
1.04
1.02
1.05
1.10
1.35
1.20
1.56
1.38
1.36
1.38
1.23
1.13
1.10
1.12
1.08
1.12
1.26
1.46
1.36
251.2
253.7
233.3
249.5
257.1
257.5
245.9
268.1
233.3
182.1
226.7
251.5
234.0
213.7
179.1
195.7
172.8
193.9
210.9
225.7
207.5
219.6
240.6
221.2
226.8
231.8
209.0
187.9
212.9
6.7
6.0
6.0
3.5
3.8
4.5
3.6
3.0
3.6
4.2
5.3
5.3
5.1
4.8
3.2
3.7
3.7
3.6
2.9
3.8
2.6
3.0
6.4
6.1
6.1
7.3
5.3
14.1
4.2
199.5
187.6
189.8
211.3
230.5
211.4
203.5
236.0
184.0
149.4
188.7
204.0
194.8
175.7
148.1
166.3
153.4
173.7
192.8
181.6
170.1
182.0
205.2
173.2
179.3
194.8
167.4
149.6
171.1
8.1
9.1
8.6
5.6
6.5
7.1
4.6
5.1
5.3
6.6
6.7
6.1
5.1
4.8
4.4
4.1
3.5
3.5
2.7
3.5
3.6
4.9
10.1
10.9
12.1
11.6
6.6
6.7
4.9
33.1
34.7
34.6
30.4
30.3
32.1
30.8
32.4
28.7
25.8
27.1
31.3
33.9
28.7
21.7
26.1
19.8
25.3
25.8
29.2
28.7
27.8
27.2
31.5
26.5
24.2
23.2
23.1
24.5
2.0
2.0
1.8 19.5
1.4
1.4
1.7
1.5
1.3
1.6
1.8
2.1
1.6
2.6 22.0
.9 20.9
.6 7.9
.3
.3
.3
.1
1.4
1.2 17.5
1.2 16.8
1.7 29.8
1.7
1.6 20.0
1.7
1.3 18.2
2.9 13.5
1.7
62.5
35.0
0.4 34.6
33.4
30.3
32.3
30.8
34.1
29.8
27.1
28.9
33.3
2.4 36.0
0.1 31.4
0.3 23.5
28.1
21.9
26.5
26.4
29.4
0.1 30.4
0.2 29.7
1.1 29.6
34.3
0.1 29.4
26.8
0.1 25.9
4.3 25.2
26.3
4.2
3.9
3.7
3.6
3.7
3.5
3.9
3.6
4-0
3.6
4.2
4.9
4.9
4.0
4.1
2.8
3.4
3.8
3.5
3.5
2.9
3.5
4.1
3.9
3.9
4.6
3.8
4.6
4.8
29.4
0.3

3.0

0.2

1.7
1.1
1.3
1.8
2.0
2.1
2.7
1.8
2.0
2.1
1.3
0.6
0.2
1.7
1.8
2.4
2.8
2.9
2.6
2.7
2.1
1.8
2.3
1.9
1.8
2.2
2.2
1.8
2.4
2.3
2.4
1.9
2.2
3.4
2.3
2.1
2.5
1.5
2.1
2.5
2.3
2.1
1.8
2.3
2.3
2.3
2.3
2.9
2.4
1.7
3.2
600
656
625
562
518
538
546
524
544
583
618
588
549
546
513
502
499
503
538
577
633
621
652
642
697
666
636
614
528

-------
CD
c
o>
CD

-P

O
cn
 O)
 E
 I
on
x
 CD
 O
 z
        80.0
                                   Lake Geneva.   Wisconsin
          11111II111111II11111II1111111II1111111111! 11M1111111II111111 It | II11II111 u 11 ll 111111 u 11II111111 ii 11U.


                                        Effluent Total Nitrogen  Limit -  10.0 mg/C
    n ri>i i rf>i I KPi I ri>i I KPi I m I TO I m i ffl i
 0.
           JFMAMJJASONDJFMAMJJASONDJFMAM
            HI III III  lit III III III llt|MI|lll|IM|MI|lll|HI|1ll|IU]lll|lll|IM|lll|IU|lll|lll|MI|lll|IM|in|l(+l
            - A  influent
            -o  Effluent
           JFMAMJJASONDJFMAMJJASONDJFMAM
        30.0
        20.0 _
10.0
         0.0

                                                    111111111M11111111111 ill I li
            JFMAMJJASONDJFMAMJJASONDOFMAM
         0.0
            JFMAMJJASONDJFMAMJJASONDJFMAM


                               January  1989 through  May  1991

-------
             Lyons, Wisconsin WUTP  - Monthly Average Data
Date
189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
591
Flow Influent Effluent Influent Effluent Effluent
HGO BOO BOD TSS TSS NH3-N
 CLbs/d) (mg/L)  (rog/L)
0.0576
0.0519
0.062
0.0622
0.067
0.0652
0.0676
0.0734
0.0736
0.0575
0.0567
0.056
0.0576
0.0663
0.1012
0.0916
0.1154
0.0923
0.0809
0.0777
0.0667
0.0649
0.069
0.0786
0.0723
0.0689
0.0866
0.1025
0.0885
247
269
258
266
267
278
274
260
218
253
249
262
278
247
191
174
144
182
231
227
247
269
237
226
256
234
206
139
188
8
7
15
10
9
7
10
10
5
6
6
10
12
7
7
10
9
7
5
3
4
3
4
4
5
6
6
5
3
119
110
124
119
115
134
139
140
127
129
141
139
134
136
105
99
81
114
140
122
138
152
154
125
120
140
124
118
130
9
13
16
14
14
9
23
29
 17
15
8
12
14
9
7
11
10
12
10
6
4
4
6
5
6
6
8
7
5
1.9
2.05
0.45
0.23
0.43
0.51
2
0.2
0.14
0.17
0.22
4
0.91
1.1
0.71
0.3
0.32
0.25
0.12
0.06
0.43
0.18
0.14
0.45
0.39
0.16
0.06
0.7
0.12
Hote: Plant reports influent NH3-N ranges from 10 -  40 mg/L.

-------
           0.20
  ^      0.15_
  a
  CD
  2:
  ~~"      o.ioC
   a
   o
   tn
   _J

   O)
   CD
   O3
                                             Lyons.   Wisconsin
           n nnnilllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllnillIT
           0.095
               JFMAMJJASONDJFMAMJJASONDJFMAM
            400
            300
            200
 100
                  Influent
               Io Effluent
                                                          urnimi ill ill ill  ill  in  HI  in  MI  in  MI lu.
                                                           1   '   kffWnt'BOD L'imlt A 30.01
                                                                                  md/b-

               JFMAMJJASONDJFMAMJJASONDJFMAM
            200
            150 _
            100_
               JFMAHJJASONDJFMAMJJASONDJFMAM
           4.00
 I
cn
C D)
UJ
3.00
           2.00
           1.00
               jj MI HIIIIIII Mill] n ii mil M 11111111111 mini i ii ii HI n nil 1111111111 MI ill iiii in it mi n ii n MM i] n MI

               -'   '   '   '   '   '   '   '   '   '  A      ' Effluent Nk3JN liimit '(sJmmdr)'- 3.01 md/
                                                       Effluent NH3-N Limit  (Winter)  - 6.0 mg/lr
                                                                                  ill
                                                                                  lid
               JFMAMJJASONDJFMAMJJASONDJFMAM


                                   January  1989  through  May  1991

-------
Morgan City,  Louisiana UUTP -  Monthly Average Data
Date
189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
Flow
(HGO)
3.283
2.221
3.254
2.906
3.793
6.143
6.061
4.890
5.373
2.987
4.636
4.680
5.660
6.220
5.020
3.120
2.850
2.48
2.48
3.38
3.98
2.54
2.71
4.32
EFF
BOOS
(mg/L)
4.053
3.933
7.786
4.991
7.521
6.269
8.666
14.810
16.530
15.150
6.285
4.307
6.330
9.640
3.970
3.610
4.040
4.220
4.320
2.990
4.100
3.190
3.560
4.290
EFF
TSS
(mg/L}
3.545
2.476
6.759
4.260
4.138
5.460
4.161
6.195
4.570
4.220
4.663
8.520
5.320
6.440
3.850
3.840
3.160
3.320
4.130
1.810
4.010
2.440
2.590
4.460
INF
NH3
(mg/L)
19.52
17.57
15.68
16.27
15.91
16.78
10.66
10.43
19.57
17.40
11.23
18.45
16.48
18.15
21.53
22.34
23.72
23.38
23.27
22.03
18.51
33.10
26.63
23.90
EFF
NH3
(mg/L)
0.24
0.40
0.19
0.19
0.24
.0.57
0.34
0.55
0.26
0.28
0.34
0.35
0.09
0.75
0.18
0.17
0.17
0.18
0.14
0.17
0.35
0.11
0.15
1.88

-------
   a
   CD
    2
    o
 a
 o
 m
 QJ Dl

 Z3 E
UJ
CD

Cfl
(D D)

ZJ E
UJ
  cn
           10.0
            e.o_
            6.0 _
 4.0_
           2.0_
                                       Morgan City.  Louisiana
           O.Oi
              JFMAMJJASONDJFMAMJJA
                                                                              S  0  N   D
50.0




40.0




30.0




20.0
          10.0
           O.Oi
                                                   Effluent  BOD Limit - 30 mg/br
             JFMAMJJASONDJFMAMJJASOND
50.0




40.0




30.0




20.0




10.0




 0.0
                                                  Effluent TSS Limit = 30 mg/f
                 iiiliiiPm?mrm?mlmTMi?i^
                                                                  i
             JFMAMJJASONDJFMAMJJA
                                                                             S  0   N  D
          50.0
                dl I lil I ill I ill I dl I ill I iL I ill I ill I ill l ill l ill i 4, i ii|, 11
             JFMAMJJASONDJFMAMJJA  S.  OND

                            January  1989 through  December  1990

-------
Mount Clemens, Michigan UWTP Monthly Averge Data
Date
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
591
691
Influent Influent Influent Influent Influent Effluent Effluent Effluent Effluent Effluent
Flow CBOO TSS TP NH3-M pH TSS NH3-N TP pH CBOO
(MOD) (mg/t) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) 
-------
   D)
   i
   en
 en
 D
 c_
 o
.c
 CL
 CO
  en
to
4J
o
H-
  CO
  X
  CL
         35.0
                                Mount  Clemens.  Michigan
          n nhl I I I I I linlnili
            JFMAMJJASOND
                                                              F   M   A   M   d
         5.00
            -Effluent Phosphorus Limit =1.0 mg/L
         4.00
3.00
         2.00
1.00
                                                                  I I I I I I I I ML
         12.



         11.0



         10.0



         9.0



         B.O _
       I"1!"1!"1!111!"1!1"!"1!"1!111!"1!111!111!111!111!111!11
                                          Effluent pH Range = 6.0 to 9.
T

0-J
         4.oD_
                                                        H I H I I I ih i i I i i i I i i

               FMAMJJASONDJF
                                                                M   A   K   J
                          January  1990  through  June  1991

-------
a
CD
 3:
 o
 r-i
 U-
       8.00
                               Mount  Clemens,  Michigan
           -4 I I  I I I  I I I  I 1 I  I 1 I  I I I  I I I  I I I  I I I   I I I  I I I M I I  I I I
           =''''  MohthlV Averages  '    '    '
           3 I i I I I I I i M I i i i I i i i I M i I i i i I i i i I i i i I i i i I  i i i I i M I i i i I i i i I i i i I i i i  I i i f-
          JrMAMJJASONDJFMAMJ
O)
E
Q
O
m
o
        200
        150
        100
         50
           j 1111111 M 111111111111111111111111111 n |TITJTI 111 rrpi i fir ry 111111 r

                                                                       A Influent"
                                                                       o Effluenr
         0 11 1^1 i i dt I I ' J)' I IJ) I I I i|i I I lj) II ijil I Iffil I lij^l I ijil I  lf}il I ijil I ijtl I I ij>Jj|JLJiJ_L 14i I I \i

          JFMAMJJASONDJFMAMd
        300
DJ
cn
tn
        200
        100;
           jll|I I I|IM|III|II I|II I|I I III I I|I I I|I II|I I I|I I I|I I I|I I I|I I I| I I I | I I I
          JrMAMJJASONDJFMAMd

                           January  1990  through  June  1991

-------
a
CD
o
IJ
U.
O)
E
O
O
CD

4J
c
(U
LU
CO
Cfl
f-
       3.00
                                 Rehoboth  Beach,   Delaware
       2.00_
i.oo_
       o.oo
                          iiilmliiiliiiliiilmliiilmliiiliiiliiiliiilmliii
           JFMAMJJASONDJFMAMJJASONDJFMA
       40.0
        30.0
20.0
        10.0
            lll|lll|lll|lll|lll|lll|lll|lll|lll III III III  III III III III III III III III Illllllllllllll IIIJIII
            - I   I   I  I  I   I   I   I    I   I   I  '      '   'Efhu^nt'eofa Limit  -' ad m
                                         lTi 1111 n 111 MI n 11111111111111111111111 mi ill imi MI 11111111 n
           JFMAMJJASONDJFMAMJJASONDJFMA
        30.0
,-^      20.0_
 0)
 E
10.0_
                    in mi mi mi mm mi mi mm mi mm mmi mi mi mi mi mi mi mi
                    11111111111111   'Efnuint'lSS Limit -'  23
                                     liilmlmlmliiiliiilill
           JFMAMJJASONDJFMAMJJASONDJFMA

                             January  1989 through April  1991

-------
Rehoboth Beach.  Delaware WHIP -  Monthly Average Data
Date

189
289
389
489
589
689
789
889
989
1089
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
391
491
001 Effluent Effluent Influent Effluent Influent Effluent Influent Effluent
Flow BOOS TSS Aitroonia Anroonia TKH TKN N03 N03
(KCD)
0.408
0.425
0.569
0.780
1.007
1.300
1.860
2.016
1.398
1.007
0.803
0.684
0.694
0.676
0.705
0.881
0.774
1.763
2.200
1.917
1.295
0.997
0.840
0.599
0.578
0.546
0.607
0.733

13.12
8.25
5.18
2.40
5.90
5.50
5.40
4.70
1.70
1.20
1.40
2.20
4.00
3.40
2.80
4.00
4.00
4.50
5.30
3.10
3.50
2.20
3.00
2.10
3.00
5.10
5.80
6.20
Cg/L)
5.18
5.16
7.93
9.60
8.40
10.00
9.90
9.10
5.70
7.60
14.10
12.00
11.00
10.00
9.40
11.00
3.00
5.00
7.00
13.00
14.30
4.70
8.00
16.50
13.00
10.00
9.90
5.70
(g/L) (sg/L) (mg/L)
4.180
1.110
0.510
7.30 0.409 24.70
10.75 3.890 23.60
16.54 0.579 28.50
16.41 1.070 30.80
13.54 0.215 26.20
7.65 0,272 22.30





13.87
15.50
26.90
36.80
33.00
34.37
25.40
18.95
14.41
16.30
13.35
16.23
(mg/L)
5.10
5.17
1.45
1.25
5.35
1.28
2.83
1.66
0.80





1.22
1.12
0.47
2:80
7.98
3.54
1.61
1.24
3.84
5.00
4.90
12.00
2.88
(mg/L)
1.67
1.93
0.74
1.75
2.56
4.05





2.51
1.97
0.10
0.15
2.10
4.27
2.95
0.37
2.51
2.94
0.62
1.06
(mg/L)
9.92
13.43
10.33
9.28
8.24
17.60
7.56
4.34
15.47





11.27
11.34
18.49
3.60
0.13
11.48
22.00
12.20
13.30
11.00
9.40
6.35
7.60
Influent Effluent
Total N Total N
(mg/L)
26.30
26.10
27.20
32.10
28.60
26.30



-

16.40
17.30
27.00
36.95
35.00
38.60
28.40
19.33
16.87
19.23
13.95
17.27
(mg/L)
14.83
18.20
11.77
10.70
13.44
17.60
11.68
5.94
16.16





12.50
12.40
18.82
6.39
8.08
14.96
23.60
13.49
17.20
16.10
14.30
18.00
10.30
Minimum
pH
(s.u.ll
7.02
6.60
6.20
6.40
6.40
5.90
6.60
6.70
6.76
6.30
6.40
6.50
6.30
6.40
6.40
6.30
6.30
6.70
6.50
6.50
6.30
6.40
6.10
6.30
6.20
6.10
6.40
6.60
Maximum
oH
r"1
7.17
7.30
7.50
7.10
7.20
7.00
7.70
7.10
7.29
7.10
7.00
7.20
7.20
7.00
7.00
6.90
6.90
7.10
7.00
7.70
6.80
7.10
7.00
6.70
6.90
7.10
8.00
7.20

-------
  O)
  c
  CD
  O)
  O
  (D
  -4J
  O
         40.0
         30.0
20.0 _
         10.0 _
                                 Rehoboth Beach,  Delaware
                                              Effluent Total N/trogen IMmit  - 5.0 mg/f
 o nhllllllllllll
            JFMAMJJASONDJFMAMJJASONDJFMA
  D)
        50.0
        40.OZ
        30.0 ~
        20.or
        10.01
           JFMAMJJASONDJFMAMJJASONDJFMA
        20.0
 O)
 fD
 rt
 C.
 O
        15.0
        10.0
         O.OUl
                                                                                TTU
           JFMAMJJASONDJFMAMJJA
                                                                           "lIlllllIT
                                                               SONDJFMA
        30.0
        25.0-
I

 I
*0
           JFMAMJJASONDJFMAMJJASONDJFMA
                           January  1989 through  April 1991

-------
                        Uanaque Valley, Neu Jersey WUTP - Monthly Average Data
Dote
1189
1289
190
290
390
490
590
690
790
890
990
1090
1190
1290
191
291
flow
(HCO)
0.75A
0.665
0.719
0.784
0.742
0.769
0.8S9
0.729
0.659
0.763
0.661
0.64
0.655
0.783
0.752
0.705
INF EFF INF EFF IMF EFF INF EFF INF EFF INF EFF Average
BOOS BODS B0020 BOD20 TKN TKN NH3 NH3 TSS TSS Tot P Tot P MUSS
 (mg/L)  (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)  (mg/L) (rag/L) (mg/L)
166.0
154.0
224.0
221.0
220.0
199.0
122.0
134.0
141.0
137.0
115.0
161.0
141.0
116.0
122.0
109.0
3.30
2.50
2.20
3.00
2.70
2.20
2.90
2.00
2.50
2.20
1.90
1.70
1.10
2.00
2.70
5.30
239
243
297
360
324
284
164
178
199
198
160
195
196
167
162
128
8.60
5.00
8.70
9.40
5.90
5.90
5.10
3.70
4.40
3.10
2.90
2.40
2.60
4.00
3.40
5.60
38.0
30.0
48.0
41.4
40.0
35.0
26.0
27.3
24.8
29.3
35.8
40.3
41.0
27.5
25.0
30.0
1.40
1.80
1.90
1.90
0.83
0.56
1.50
0.91
0.84
0.65
0.37
0.47
0.65
1.00
0.90
1.40
23.0
19.0
40.0
18.0
40.0
18.6
18.4
19.9
23.0
20.0
20.8
26.3
26.8
15.8
15.9
17.5
0.46
0.77
0.67
0.51
0.76
0.30
0.14
0.41
0.12
0.14
0.12
0.13
0.15
0.29
0.30
1.19
104
117
188
127
120
76
105
95
121
140
138
132
164
93
125
104
1.80
2.70
3.00
6.50
5.00
5.00
3.70
3.20
1.90
2.20
1.12
2.00
2.90
6.40
7.20
6.30
4.6
2.0
3.6
3.9
5.0
4.1
3.7
4.3
3.9
4.3
4.8
5.5
5.1
3.1
3.2
3.5
1.20
1.10
0.54
0.88
0.84
0.75
0.70
0.84
0.48
0.57
0.66
0.58
0.41
0.44
0.42
0.35
2684
1941
2507
2009
2318
2447
2275
2043
2300
2280
2523
2639
2829
3540


Mote: Began adding chemicals for phosphorus removal in January, 1990

-------
o
o
i-H

li-
in
d
o
m
 en
 e
o
cxi
a
o
ca
 en
en
      2.00
       1.50
       i.oo
0.50
       0.00
                     Wanaque  Valley,  New  Jersey

   JI I  I I I I I I I I I  I I I I I I I I  I I I I I I II I I I I I I  I I I I I I I I  I | II
        11111    Monthly Av'eragfes   '
                                                                 I I I  I  I I  I I L
          -i i i I ii i I i i i I i i  i I i i i I i i  i I i i i I i  i i I i i i I i  i i I i i i I  i i i I i i i I  i i i I i i r
          NDJFMAMJJASONDJF
       400
       300 _
       200 _
 100 _
          J I I  I I  I  M I  I  M  I I I  I M  I I I  I  M  I I I  I  I I  I I I   I I I  I I I   I I I  I I L
          NDJFMAMJJASONDJF
        BOO
          J I I   I I I  I I I   I II  I I I  I  I I  I I I   I I I  I I I   I I I  I I I  | I I I | I II | I I I | I I L
        600
        400
          NDJFMAMJJASONDJF
        300
        200
                I I I | II I  | I I I | I I I  | I I I | I I  I [ I I I | II I | I I I | I I  I | I I I | II I | I I I | I I  l_
            llJJllUl!l(lTlllrtilllLllrfilflf|1l"rlil"fl1lllf1illl-l-l"-|-llli"1^11''^
          NDJFMAMJJASONDJF


                       November  1989 through  February  1991

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        BO.O
                      Wanaque  Valley,  New Jersey
                     | l l l  | l l I | l l l | M I I  l I l | l l l | l i l  | i i i | i M | l i  i
              Influent
           f-o Effluent
 O)
 e
to
__)
O
          NDJFMAMJJASONDJ
       50.0
                                 I I I | I I I | I  M | | M | I I I | I  I I | I I | | | | | |  I I I | I I M
       40.0_
       30.0_
 CD     20.0_
       10.0_
          NDJFMAMJJASONDJ
       20.0
          J " | N ' | I  ' I | I I I | II I | I I  I | I I I | I H | I  I I  I I I  I I I  I I  I  I I I  I I I  I  |
 CD

J     15.0
(0
3
C.
O
x:
Q.
CO
O

Q.
10.0
       5.0_
        .oTTTTTlTr^rn T111T
                                                               -MO I I Id) I M
         NDJFMAMJJASONDJF

                      November 1989 through February 1991

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        20.
        15.0
 D)
 m
        10.0
        5.0
        O.Ot
                        Gwinnett  County,  Georgia
                                                     Effluent NH3 Limit = 1.0 mg/L
          JFMAMJJASNDJFMAMJJASOND
o
D-
       50.
       40.0_
^7     30.0_
                                                    Effluent P04 Limit - 0.5 mg/l_
20.0_
       10.0_
         JFMAMJJASNDJFMAMJJASOND

                       January 1989 through  December  1990

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GU1NHETT COUNTY WATER RECLAMATION DIVISION
IMF EFF INF EFF IMF
A.D.F. BOD BOD TSS TSS NIB
(HOD) (mg/L)  (mg/L)
0.300
0.200
0.200
0.140
0.170
0.090
0.390
0.140
0.040
0.430
0.500
0.310
0.520
0.526
0.880
0.050
0.084
0.030
0.600
0.060
0.060
0.063
0.090
0.310






35.3
31.6
22.9
28.7
28.4
48.7
24.3
23.4
20.1
22.0
31.7
10.3
8.4
7.4
8.1
10.5
7.0
8.9
6.8
5.5
5.8
5.4
7.0
6.2






EFF
P04
(mg/L>
0.30
0.20
0.20
0.33
0.36
0.28
0.21
0.31
0.16
0.18
0.11
0.55
0.19
0.18
0.25
0.39
0.38
0.31
0.23
0.14
0.14
0.17
0.13
0.19






EFF AVG
N03 HLSS
(mg/L) 
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    Q

    CD
            15.0
                                       Gwinnett  County.  Georgia
            10.0 _
             5.0 _
             n nlTlllllllllllllllllllllllllllHllllllllllHllnilllllllllllllllllllllllllllllllllllllllllm


               JFMAMJJASONDJFMAMJJASOND
    cn
    a
    o
    ca
     O)
   CO
    cn
                                                                  Effluent BOD Limit - 5.0 mg/L.
                -A influent
                  o Fffluen
                 71 ill i ill i ill i lit i ill i ill i ill i ill i ill i ill I ill I ill i ill i ill i ill i ill i ill I ill I ill i ill i ill i ill 11
                JFMAMJJASONDJFMAMJJASOND
            2000
                                                                  Effluent TSS Limit - 8.0  mg/IT
                       ll i ill i ill i ill i ill i ill i ill i ill i ill i ill I ill I ill I ill I ill I ill I ill I ill I ill I ill I ill I ill 11.
                       MAMJJASONDJFMAMJJASOND


                                January  1989  through December  1990
                                 S. Government Printing Office : 1992 - 312-014/40168

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