FINAL

Total Maximum Daily Load  (TMDL)




                        For

        Organic Enrichment & Dissolved Oxygen

Tombigbee River (Aliceville Reservoir)   AL/03160106-0402-102


                Pickens County, Alabama


                      Prepared by:

                    US EPA Region 4
                   61 Forsyth Street SW
                   Atlanta, Georgia 30303
                     October 2008

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Tombigbee River (Aliceville Reservoir)	FINAL - Organic Enrichment/Dissolved Oxygen


Table of Contents


List of Figures	iv

List of Tables	iv

List of Abbreviations	v

1.0        Executive Summary	1

2.0        Basis for the §303(d) Listing	4

3.0        Technical Basis for TMDL Development	7

3.1        Applicable Water Quality Criterion	7

3.2        Source Assessment	7
  3.2.1    Nonpoint Sources	9
  3.2.2    Point Sources	10

3.3        Data Availability and Analysis	13
  3.3.1    Instream Water Quality	13
  3.3.2    Other Available Data	15

4.0        Model Development	16

4.1        Environmental Fluid Dynamics Code (EFDC)	16

4.2        Water Quality Analysis Simulation Program (WASP)	17

4.3        Past QUAL2E Model Applications to the Tombigbee River	17

5.0        Development of Total Maximum Daily Load	19

5.1        Numeric Targets for  TMDL	19

5.2        Existing Conditions	19

5.3        Critical Conditions	20

5.4        Margin of Safety (MOS)	21

5.5        Seasonal Variation	21



Prepared by US Environmental Protection Agency, Region 4.                            ii

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Tombigbee River (Aliceville Reservoir)	FINAL - Organic Enrichment/Dissolved Oxygen






5.6         TMDL Results	22





6.0         Conclusions	25





8.0         References	27
Prepared by US Environmental Protection Agency, Region 4.

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
List of Figures
Figure 1.     Aliceville Reservoir in the Tombigbee River Basin	vi
Figure 2:     Land Use Classification in the Aliceville Reservoir Watershed	9
Figure 3:     Major Discharges of BOD to the Tombigbee River Above Aliceville
             Reservoir	12
Figure 4:     Model of Aliceville Reservoir showing water quality monitoring stations.... 15
List of Tables

Table 1:      OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville
             Reservoir	3
Table 2:      OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville
             Reservoir	3
Table 3:      Landuse Distribution for Watersheds Draining to Aliceville Reservoir	10
Table 4:      Major NPDES Permitted Discharges of BOD to the Tombigbee River
             Upstream of Aliceville Reservoir (HUCs 03160101 and 03160106)	11
Table 5:      Existing Discharge (2003-2006) for Major NPDES Facilities to the
             Tombigbee River Upstream of Aliceville Dam	13
Table 6:      Water Quality Stations in Aliceville Reservoir	14
Table 7:      Existing Discharge (2003-2006) for Major NPDES Facilities	20
Table 8:      Estimated Nonpoint Source Loads from  Stennis Dam to Bevill Dam	20
Table 9:      OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville
             Reservoir	23
Table 10:     OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville
             Reservoir	24
Prepared by US Environmental Protection Agency, Region 4.
                                IV

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Tombigbee River (Aliceville Reservoir)
                         FINAL - Organic Enrichment/Dissolved Oxygen
List of Abbreviations
ADEM
BOD
BOD-5
CAFO
CBOD
CBODu
CFR
CFS
DMR
DO
EPA
GIS
HUC
LA
MDEQ
MOD
MOS
MRLC
NBOD
NH3-N
NOBDu
NPDES
POTW
SOD
TMDL
TN
TP
USGS
WCS
WLA
WWTP
7Q10
Alabama Department of Environmental Management
Biochemical Oxygen Demand
5-Day Biochemical Oxygen Demand
Concentrated Animal Feeding Operation
Carbonaceous Biochemical Oxygen Demand
Ultimate Carbonaceous Biochemical Oxygen Demand
Code of Federal Regulations
Cubic Feet per Second
Discharge Monitoring Report
Dissolved Oxygen
U.S. Environmental Protection Agency
Geographic Information System
Hydrologic Unit Code
Load Allocation
Mississippi Department of Environmental Quality
Million Gallons per Day
Margin of Safety
Multi-Resolution Land Characteristic
Nitrogenous Biochemical Oxygen Demand
Ammonia Expressed as Concentration of Nitrogen
Ultimate Nitrogenous Biochemical Oxygen Demand
National Pollutant Discharge Elimination System
Publicly Owned Treatment Works
Sediment Oxygen Demand
Total Maximum Daily Load
Total Nitrogen
Total Phosphorus
United States Geological Survey
Watershed Characterization System
Waste Load Allocation
Wastewater Treatment Plant
7-day Average Low Flow with a Recurrence Interval of Once in Ten Years
Prepared by US Environmental Protection Agency, Region 4.

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
                 Figure 1.      Aliceville Reservoir in the Tombigbee River Basin
Prepared by US Environmental Protection Agency, Region 4.
                                     VI

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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
 1.0   Executive Summary

 This report presents the Total Maximum Daily Load (TMDL) for the Tombigbee River
 from Bevill Dam to the Alabama/Mississippi state line (Aliceville Reservoir), which is
 listed as impaired by organic  enrichment/low dissolved oxygen on Alabama's 2008
 Section  303(d) list.    TMDLs  are required  under the  Clean  Water  Act  when
 technologically based controls on  permitted  point sources alone  are  insufficient to
 achieve water quality standards.

 Aliceville Reservoir is an impoundment of the Tombigbee River  located in Pickens
 County,  Alabama, near the Alabama/Mississippi state line.  The reservoir is operated
 primarily to  support navigation on  the  Tennessee-Tombigbee  Waterway and is
 characterized by low  velocities and high temperatures during summer drought periods.
 The contributing upstream watershed for Aliceville Reservoir occupies an area of 5,750
 square miles, most of which is within the State of Mississippi.

 Aliceville Reservoir  has  two  designated use  classifications:  Fish and Wildlife  and
 Swimming.   In accordance with  Alabama Department of Environmental Management
 (ADEM) water quality standards, the minimum dissolved oxygen (DO) concentration in a
 waterbody with these  use classifications is 5 mg/L, except in extreme conditions due to
 natural causes where DO levels are not permitted to drop below 4 mg/L.

 Aliceville Reservoir  was  originally  placed  on Alabama's 1996 § 303(d) list as  not
 supporting designated uses based on water quality monitoring data collected in 1991  that
 showed DO concentrations less than  5 mg/L,  and occasionally less than 4 mg/L.  More
 recent data, collected  by ADEM  in 1999, 2001, 2003, 2004 and 2006  and by EPA in
 2005, shows that DO values in Aliceville Reservoir continue to drop  below 5 mg/L.
 Analysis of available monitoring data indicates that  excursions of the water quality
 criterion for DO in Aliceville Reservoir are associated with conditions of low flow  and
 high water temperatures. Under these conditions, the ability of water to hold dissolved
 oxygen is reduced, the rate of reaeration of the water is  slowed,  and the effects of
 oxygen-consuming wastes on the DO balance in the water column  are enhanced.

 Three models were coupled and used to predict the reductions required to meet water
 quality  standards.  These modeling tools include: 1)  an application of the watershed
 model,  BASINS PLOAD; 2)  an application of the hydrodynamic, three-dimensional
 model, Environmental Fluid Dynamics Code (EFDC); and 3) an application of the Water
 Quality  Analysis Program  (WASP) 7.2 eutrophication model.   These models were
 calibrated to observed data in the reservoir.

 In order to  achieve the applicable  water quality standards, the TMDL estimated by these
 models requires a reduction of 30  percent from the total existing loads of CBODu, Total
 Phosphorus (TP), and Total Nitrogen (TN) that enter Aliceville Reservoir.   Although
 Aliceville Reservoir is not specifically identified as impaired for nutrients on Alabama's
 § 303(d) list,  reductions  to TP  and  TN are  necessary  to  meet a  minimum  DO
 concentration of 5 mg/L. Based upon information currently available, the reductions and

	  1
 Prepared by US  Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
associated  allocations  for  TP  and TN are not  expected to cause or  contribute to
excursions  of water quality standards to any downstream waterbodies.  The sources of
CBODu, TN,  and TP originate  in both  Alabama and  Mississippi.   The TMDL is
composed of three categories of allocations:  1)  a wasteload allocation  for the point
sources in Alabama; 2) a load allocation for the nonpoint sources in Alabama; and 3) an
aggregate allowable pollutant  load,  which  includes  both  the  point  and  nonpoint
contributions, to Mississippi sources in the Tombigbee River watershed to be allocated at
the state line. Table 1 shows the maximum daily loads that will meet and maintain water
quality  standards  during  the  critical  conditions  experienced each summer (June -
September). Loads for non-summer months can be higher than those in Table 1, as long
as the annual average does not exceed the allocations in Table 2.

The percent reduction required for CBODu, TN and TP represented in the tables below is
the same as the reduction prescribed in the draft TMDL  EPA proposed in October 2007;
however, the calculated loads allocated in the final  TMDL are greater than the calculated
loads proposed  in the draft TMDL. In both the proposed and final TMDLs, loads at the
MS/AL state line  are calculated using results from  the same water quality model. In the
proposed draft TMDL, the loads at the MS/AL  state line were  based on output from one
model layer when it should have accounted for the loads  from all of the layers in the three
dimensional model.  This error was caught during the  public comment period and the
final TMDL loads at the  MS/AL  state line are approximately two-thirds greater than
those reported in the proposed TMDL.  The allocations  in the  final TMDL represent the
total assimilated  loads at the MS/AL  state line necessary  to achieve water quality
standards.
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
Table  1: OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville Reservoir
                                             (June - September)
Pollutant
CBODu
TN
TP
ALABAMA
Coal Fire Creek
Watershed
(HUC 3160106) 1'5
LA
30% reduction
(1,200lbs/day)
30% reduction
(17 Ibs/day)
30% reduction
(4 Ibs/day)
All other watersheds
(HUC 03160101, 03160103, and
03160105) 2'5
WLA
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
LA
30% reduction
30% reduction
30% reduction
MISSISSIPPI
Aggregate allocation to
pollutants from
Mississippi at the state
border5
30% reduction
(83,956 Ibs/day)
30% reduction
(9,606 Ibs/day)
30% reduction
(1,663 Ibs/day)
TMDL4
30% reduction
(85, 156 Ibs/day)
30% reduction
(9,623 Ibs/day)
30% reduction
(1,667 Ibs/day)
     The Coal Fire Creek watershed (HUC 03160106) is the only watershed in the  Alabama portion of the Tombigbee River basin that
     does not drain into Mississippi; therefore, loads from this watershed are not reflected in the aggregate allocation to Mississippi.
     All other watersheds in Alabama (Bull Mountain Creek (03160101), Buttahatchee Creek (03160103), and Luxapallila Creek
     (03160105)) drain from Alabama to Mississippi before ultimately draining back to Alabama and into Aliceville Reservoir. The only
     point sources in Alabama discharge to these watersheds.
     The wasteload allocation of 0 Ibs/day recognizes that there are currently no point sources in Alabama that impact dissolved oxygen
     levels in Aliceville Reservoir. In order to be consistent with this wasteload allocation, any potential future discharges in Alabama can
     only discharge TN, TP, or CBODu loads within the Basin if they are determined to not have any impact on the dissolved oxygen
     levels in Aliceville Reservoir.
     The TMDL is calculated by adding the aggregate allocation at the Mississippi border to the LA for the Coal Fire Creek watershed.
     The WLA to the Alabama point sources and the LA to the other Alabama watersheds were not added in the TMDL calculation,
     because their allocations are already reflected in the aggregate allocation to Mississippi.
     Pollutant trading may occur between the loads allocated to nonpoint sources in Alabama and Mississippi if: (1) MDEQ and ADEM
     agree to trade; and (2) such trading results in an overall 30% reduction of CBODu/TN/TP loads to Aliceville reservoir.
     Table 2:  OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville Reservoir
                                            as an Annual Average
Pollutant
CBODu
TN
TP
ALABAMA
Coal Fire Creek
Watershed
(HUC 3160106) 1'5
LA
30% reduction
(2,600 Ibs/day)
30% reduction
(29 Ibs/day)
30% reduction
(6 Ibs/day)
All other watersheds
(HUC 03160101, 03160103, and
03160105) 2'5
WLA
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
LA
30% reduction
30% reduction
30% reduction
MISSISSIPPI
Aggregate
allocation to
pollutants from
Mississippi at the
state border5
30% reduction
(181, 952 Ibs/day)
30% reduction
(16,311 Ibs/day)
30% reduction
(2,633 Ibs/day)
TMDL4
30% reduction
(184,552 Ibs/day)
30% reduction
(16,340 Ibs/day)
30% reduction
(2,639 Ibs/day)
     The Coal Fire Creek watershed (HUC 03160106) is the only watershed in the  Alabama portion of the Tombigbee River basin that
     does not drain into Mississippi; therefore, loads from this watershed are not reflected in the aggregate allocation to Mississippi.
     All other watersheds in Alabama (Bull Mountain Creek (03160101), Buttahatchee Creek (03160103), and Luxapallila Creek
     (03160105)) drain from Alabama to Mississippi before ultimately draining back to Alabama and into Aliceville Reservoir. The
     only point sources in Alabama discharge to these watersheds.
     The wasteload allocation of 0 Ibs/day recognizes that there are currently no point sources in Alabama that impact dissolved oxygen
     levels in Aliceville Reservoir. In order to be consistent with this wasteload allocation, any potential future discharges in Alabama
     can only discharge TN, TP, or CBODu loads within the Basin if they are determined to not have any impact on the dissolved
     oxygen levels in Aliceville Reservoir.
     The TMDL is calculated by adding the aggregate allocation at the Mississippi border to the LA for the Coal Fire Creek watershed.
     The WLA to the Alabama point sources and the LA to the other Alabama watersheds were not added in the TMDL calculation,
     because their allocations are already reflected in the aggregate allocation to Mississippi.
     Pollutant trading may occur between the loads allocated to nonpoint sources in Alabama and Mississippi if: (1) MDEQ and ADEM
     agree to trade; and (2) such trading results in an overall 30% reduction of CBODu/TN/TP loads to Aliceville reservoir.
Prepared by US Environmental Protection Agency,  Region 4

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Tombigbee River (Aliceville Reservoir)	FINAL - Organic Enrichment/Dissolved Oxygen


2.0    Basis for the §303(d) Listing
Section 303(d) of the Clean Water Act (CWA), as amended by the Water Quality Act of
1987 and EPA's Water Quality Planning and Management Regulations [(Title 40 of the
Code  of Federal Regulations (CFR),  Part 130)],  requires states to identify waterbodies
which  are  not meeting water quality  standards  applicable to their  designated  use
classifications.  The identified waters are prioritized based on severity of pollution with
respect to designated use classifications. TMDLs for all pollutants  causing violation of
applicable water quality standards are established for each identified water.  Such loads
are established at levels necessary to implement the applicable water quality standards
with seasonal variations and margins of safety.   The TMDL process establishes the
allowable loading of pollutants, or other quantifiable parameters for a waterbody, based
on the relationship between pollution sources and instream water quality conditions, so
that states can establish water-quality based controls to reduce pollution from both point
and non-point sources and restore and maintain the  quality of their water resources
(USEPA, 1991).

Aliceville Reservoir, an impoundment of the Tombigbee River, is located in the Middle
Tombigbee-Lubbub hydrologic unit (HUC 03160106) in Pickens County, Alabama and
Lowndes County, Mississippi. The reservoir was formed by the closure of Tom Bevill
Dam in 1980 and is a part of the Tennessee-Tombigbee waterway.  The State of Alabama
has identified the segment of the Tombigbee River from Bevill Dam upstream to the
Alabama/Mississippi  state  line  (segment ID  AL/03160106-0402-102),  which   is
coincident with the Alabama portion of Aliceville Reservoir, as being impaired by flow
alteration(s)  and  organic  enrichment/low   dissolved  oxygen.   The beneficial  uses
identified by Alabama for Aliceville Reservoir  are Fish and Wildlife  and  Swimming
(ADEM  Admin.  Code  R. 335-6-11-.02), which jointly cover best usages  including
propagation of aquatic life,  contact and non-contact recreation, and fish consumption.
Aliceville Reservoir was originally placed on the 1996  § 303(d) list as not  supporting
designated  uses because water quality  monitoring data  collected in 1991  showed DO
concentrations less than 5  mg/L, and occasionally less than 4 mg/L. More recent data,
collected by ADEM in 1999, 2001, 2003 and 2006 and by EPA  SESD  in 2005, shows
that DO values in Aliceville Reservoir continue to drop below 5 mg/L.  The listing has
been reported on Alabama's 1996 through 2008 § 303(d) lists of impaired waters.  The
Tennessee-Tombigbee Waterway, which drains from Mississippi to Aliceville reservoir,
is not listed as impaired on the 2008 Mississippi § 303(d) List of Waterbodies.

Low dissolved oxygen concentrations are associated with "organic enrichment"  - the
presence  of  excess  amounts  of oxygen-consuming  organic matter.    Water quality
problems are exacerbated  by "flow alterations" - specifically the modifications to the
natural flow  of the Tombigbee River associated with the construction  of Bevill  Dam,
which  resulted in increased residence time, decreased velocity, and  decreased reaeration
within this waterbody segment. Mitigation of flow alteration is not addressed  in TMDLs
under current regulations.
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
The purpose of this TMDL is to establish the acceptable loading of organic material from
all sources, such that the State of Alabama water quality criterion for dissolved oxygen is
not violated.

Usage of waters in the Fish and Wildlife classification is described in ADEM Admin.
Code R. 335-6-10-.09(5)(a), (b), (c), and (d).

       a)     Best usage of waters:

       Fishing, propagation offish, aquatic life, and wildlife, and any other usage except
       for swimming and water-contact sports or as a source of water supply for drinking
       or food processing purposes.

       b)     Conditions related to best usage:

       The waters will be  suitable for fish, aquatic life and wildlife propagation. The
       quality of salt and  estuarine waters to which  this classification is assigned will
       also be suitable for the propagation of shrimp and crabs.

       c)     Other usage  of waters:

       It is recognized that the waters may be  used for incidental water contact and
       recreation during June through September, except that water contact is strongly
       discouraged in the vicinity of discharges or other conditions beyond the control of
       the Department or the Alabama Department of Public Health.

       d)     Conditions related to other usage:

       The  waters,  under  proper  sanitary   supervision  by  the   controlling   health
       authorities, will meet  accepted criteria of water quality for outdoor swimming
       places  and will be  considered satisfactory for swimming and other whole body
       water-contact sports.

       Usage  of waters in the Swimming classification is described in ADEM Admin.
       Code R. 335-6-10-.09(3)(a) and (b).

       a)     Best usage of waters:

       Swimming  and  other whole body  water-contact  sports.   In   assigning this
       classification to waters intended for  swimming  and water-contact sports,  the
       Commission will take into consideration the relative proximity of discharges of
       wastes and will recognize the potential hazards involved in  locating swimming
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
       areas  close  to  waste  discharges.  The  Commission  will  not  assign  this
       classification to waters, the bacterial quality of which is dependent upon adequate
       disinfection of waste and where the interruption of such treatment would render
       the water unsafe for bathing.

       b)     Conditions related to best usage:

       The  waters,  under  proper  sanitary  supervision  by  the  controlling  health
       authorities, will meet accepted standards of water quality for outdoor swimming
       places and will be considered satisfactory for swimming and other whole body
       water-contact  sports.  The  quality  of waters will  also  be  suitable   for  the
       propagation of fish,  wildlife and aquatic  life. The  quality  of salt waters and
       estuarine waters to which this classification is  assigned will be suitable for the
       propagation and harvesting of shrimp and crabs.

Alabama's water  quality criteria for Fish  and Wildlife and Swimming  uses  (ADEM
Admin. Code R. 335-6-10-.09-(5)(e)(4.)  and Admin. Code R. 335-6-10-.09-(3)(c)(4.))
state that "for a diversified warm  water biota,  including  game  fish, daily dissolved
oxygen concentrations shall not be less than 5 mg/L at all times; except under extreme
conditions due to natural causes, it may range between 5 mg/L and 4 mg/L, provided that
the water quality is favorable in all  other parameters.  The normal seasonal and daily
fluctuations shall  be maintained above these  levels...  In the application of dissolved
oxygen criteria referred to above, dissolved oxygen shall be measured at a depth of 5 feet
in waters 10 feet  or greater in depth; and  for those waters less than  10  feet in depth,
dissolved oxygen criteria will be applied at mid-depth."

ADEM's water quality standards applying to nutrients are narrative as stated in ADEM's
Administrative Code, Rule 335-6-10-.06:

       The following minimum conditions are applicable to all State waters, at all places
       and at all times, regardless of their uses:
       (a) State waters shall be  free from  substances attributable  to sewage, industrial
       wastes or other wastes that settle in forming bottom deposits which are unsightly,
       putrescent or interfere directly or indirectly with any classified water use.
       (b) State waters shall be free from floating debris, oil, scum, and  other  floating
       materials attributable to sewage,  industrial wastes  or other  wastes in  amounts
       sufficient to be unsightly,  or which interfere directly or  indirectly with any
       classified water use.
       (c) State waters shall be  free from  substances attributable  to sewage, industrial
       wastes or other wastes in concentrations or combinations, which are  toxic  or
       harmful to human, animal, or aquatic life to the extent commensurate  with the
       designated usage of such waters.
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
3.0    Technical Basis for TMDL Development
  3.1  Applicable Water Quality Criterion
As described in  Section 2.0, the minimum dissolved oxygen (DO) concentration in a
stream classified as Fish  and Wildlife or Swimming is 5 mg/L, except under extreme
conditions due to natural causes where a concentration  of 4 mg/L will be allowed. The
target is established at a depth of 5 feet in water 10 feet or greater in depth; for those
waters less than 10 feet in depth, dissolved oxygen criteria are applied at mid-depth. The
target CBODu, TP and TN concentrations may not deplete the daily dissolved oxygen
concentration below this level as a result of the decaying process.

Aliceville Reservoir is classified for Fish and Wildlife and  Swimming  uses.  For
navigation purposes, flows are controlled to maintain a minimum depth of 9 feet. Depths
at the downstream end of the listed reach, just above Aliceville Dam, remain greater than
10 feet.  In  sum, the primary water quality target is a  DO concentration of 5 mg/L or
greater at a depth of approximately 5 feet.

  3.2  Source Assessment
Both point and nonpoint sources may  contribute external loads of BOD, TP and TN to a
given water  body.  These sources of organic enrichment may arise anywhere within the
upstream watershed, which constitutes an area of approximately 5,750 square miles in
Mississippi  and Alabama and  comprises  six  8-digit USGS watersheds.    These
watersheds, along with the major streams and rivers, are shown in Figure  1.  Major point
sources of organic enrichment include wastewater treatment plants and paper mills, both
of which are present in the Tombigbee watershed. Potential nonpoint sources of organic
loading are numerous and often occur in combination. In rural areas, runoff can transport
significant loads of organic material from natural sources and agricultural  lands, while
onsite wastewater (septic)  systems can contribute a steady source of oxygen-consuming
wastes to groundwater.  Nationwide, poorly treated municipal sewage comprises a major
source of organic compounds that decay and create additional organic loading.  Urban
storm water  runoff, wastewater treatment discharges, and sanitary sewer overflows can
also be significant sources of organic loading.
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
                                              Tombigbee River |
                                                       Bull Mountain Creek |
                               20
                                             20      40 Miles
                  Figure 1: Watersheds Upstream of Aliceville Reservoir

Internal sources of organic enrichment include  the  biomass of plankton  and rooted
aquatic plants that grows in a waterway. Plants respire and consume oxygen, and dead
plant material is available for digestion by bacteria and zooplankton.  However,  plants
also produce oxygen as a byproduct of photosynthesis.  During periods of active growth,
aquatic plants may provide  a net positive contribution to dissolved  oxygen on a daily
average basis.  Elevated  nutrient loads to  a  watershed  may  enhance the  internal
production of organic enrichment.

Oxygen demand is also exerted by organisms that consume organic matter on and in the
sediments. The net impact of this process is known as sediment oxygen demand (SOD).
SOD arises from the deposition of organic matter to the sediments; it thus tends to reflect
a combination of the current and past history of external and internal sources of organic
enrichment.

Potential  sources  of organic  loading in the  watershed were identified  based on  an
evaluation of current land use/cover  information (e.g., urban high density  or forested
land) and an assessment of current NPDES dischargers to the watershed.   The source
assessment was used as the basis of development of the model and ultimate analysis of
the TMDL allocations. Organic and nutrient loading within the watershed includes both
point and non-point sources.
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
  3.2.1   Nonpoint Sources
Nonpoint source contributions of oxygen consuming wastes include runoff from various
landuses and septic systems.  Landuse information was derived from the National Land
Cover Dataset (NLCD), 2001, and is presented in Figure 2.  The predominant land uses
are forest (55 percent) and agriculture (31 percent). Of the agriculture, the bulk of which
is located in Mississippi, approximately  50 percent  is pastureland  and 50 percent is
cropland.
      |   | HUC 8 Watersheds
      National Land Cover Class
        ^\ Open Water
        ^| Developed. Open Space
        ~^\ Developed. Low Intensity
       | Developed. Medium Intensity
        | Barren Land
      ^^| Unsolidated Shore
        _] Deciduous Forest
        | Evergreen Forest
        ~] Mixed Forest
      j^B Dwarf Scrub
        ^] Grassland/Herbaceous
      ^^| Pasture/Hay
      ^^| Cultivated Crops
      ^m Forested Wetland
      |   | Scrub/Shrub Wetland

                    M
                        50
                       =i Miles
            Figure 2: Land Use Classification in the Aliceville Reservoir Watershed
Watersheds  1  through  6 in Figure  2 correspond to the six 8-digit  HUCs draining to
Aliceville Reservoir.   Table  3 summarizes  the  land use distribution for each of these
watersheds.
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
        Table 3:  Landuse Distribution for Watersheds Draining to Aliceville Reservoir
                                 (acres and percent)
ID
1
2
3
4
5
6
Watershed
Name/HUC
Upper
Tombigbee
03160101
Buttahatchee
03160103
Luxapallila
03160105
Town
03160102
Tibbee
03160104
Middle
Tombigbee
03160106
Total
Agriculture -
Cropland
163,641
(15.7%)
32,572
(5.8 %)
41,175
(8.1 %)
98,762
(22.2 %)
167,024
(23.7 %)
188,005
(18.0%)
691,179
(16.1 %)
Agriculture -
Pasture
170,037
(16.4%)
39,774
(7.1 %)
42,566
(8.4 %)
135,302
(30.4 %)
153,196
(21.8%)
134,216
(12.8%)
675,091
(15.7%)
Barren/
Mining
910
(0.1 %)
544
(0.1 %)
238
(0 %)
208
(0 %)
650
(0.1 %)
1,077
(0.1 %)
3,627
(0.1 %)
Forest
642,021
(61.7%)
408,270
(73.1 %)
364,342
(71.6%)
181,173
(40.8 %)
295,845
(42.0 %)
485,116
(46.4 %)
2,376,767
(55.3 %)
Transitional
38,760
(3.7 %)
27,322
(4.9 %)
13,278
(2.6 %)
2,032
(0.5 %)
7,987
(1.1 %)
18,909
(1.8%)
108,288
(2.5 %)
Urban
11,700
(1.1 %)
4,187
(0.7 %)
5,980
(1.2%)
15,809
(3.6 %)
8,333
(1.2%)
4,031
(0.4 %)
50,040
(1.2%)
Water/
Wetlands
12,686
(1.2%)
45,751
(8.2 %)
41,399
(8.1 %)
11,232
(2.5 %)
71,103
(10.1 %)
213,679
(20.4 %)
395,850
(9.2 %)
The predominant land use is forest, followed by agricultural. This watershed is primarily
rural, so agricultural loads of organic material during storm wash-off events could be
significant.  Residential land uses constitute less than 1 percent of the watershed, and
loads from onsite wastewater disposal systems are unlikely to be significant relative to
other load sources.

  3.2.2   Point Sources
ADEM  and  the  Mississippi Department of Environmental  Management  (MDEQ)
maintain databases of current NPDES permits and GIS files that locate each  permitted
outfall.   These databases  include  municipal, semi-public/private, industrial, mining,
industrial  storm water, and concentrated animal feeding operations (CAFOs) permits.
There are a total  of 166  Mississippi and Alabama NPDES permits with BOD effluent
limitations in Tombigbee  River HUCs 03160101 through 03160106 (USEPA PCS Query,
8/13/07).  The majority of these permits are for small facilities.

There are ten major dischargers with BOD effluent limits within the six HUCs upstream
of Aliceville Reservoir.   Two dischargers without BOD limits (EKA Chemical and
Sanderson) are also  included because of proximity to the reservoir.  EKA Chemical,
which manufactures hydrogen peroxide and sodium chlorate (according to MDEQ), has a
total organic  carbon (TOC) limit from which BOD may be estimated.   Sanderson
manufactures wood products and also reports its effluent BOD concentration. The two
major dischargers closest to Aliceville reservoir are Columbus POTW and Weyerhaeuser
Paper Mill. All dischargers are summarized in Table 4 and Figure 3.
                                                                               10
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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
   Table 4: Major NPDES Permitted Discharges of BOD to the Tombigbee River Upstream of
                     Aliceville Reservoir (HUCs 03160101 and 03160106)
NPDES
Permit #
MS0001783
MS0003158
MS0045489
MS0055581
AL0048372
MS0020788
MS0036111
AL0023400
MS0056472
MS0036412
MS0040215
MS0002216
Facility Name
Bryan Foods
True Temper
Sports/Emhart
Amory POTW
Aberdeen POTW
Hamilton POTW
West Point POTW
Tupelo POTW
Winfield POTW
Columbus POTW
Weyerhaeuser CPPC
EKA Chemical
Sanderson
Facility Type
Meat Packing
Plating
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Paper Mill
Chemical
Wood Products
Flow
(MGD)
2.65 T
0.346 m
2
4
2.64 T
3.5
10.5
0.353T
10
19T
0.655 T
0.23 T
5- day BOD
Limit (Ib/d)
375 a
78b
751
1501,1001°
352
525'/876J
2,627
225 /183s
2,168
21,954°
32T
3.3T
Ammonia
(Ib/d)
50 / 44 n
0.033L
33K
58T
132
58K
175'/350J
76.7/49.2 3
500
192T
NA
NA
     a.  Pemitted CBOD5 limit.
     b.  No BOD5 limit for pipe 1; table shows average discharge from 8/05 to 12/06.
     c.  Permitted BOD5 limit was 1501 through Dec. 2004, then 1001 Jan. 2005 through present.
     d.  Variable limit based on temperature and flow conditions of the Tombigbee River, table shows monthly
        average permitted discharge.
     e.  No BOD limit specified, has a permitted TOC limit of 73 Ib/d as of Nov. 2005.
     f  No permit limit;  table shows average discharge from 1/03 to 12/06.
     g.  2003-Aug. 2006 limit, then Sep. 2006 to present limit.
     h.  2003-July. 2006  limit, then Aug. 2006 to present limit.
     i.  Summer limit (May - Oct..)
     j.  Winter limit (Nov. -Apr.).
     k.  Estimated ammonia from permitted discharge and assumed ammonia cone, of 2 mg/L.
     1.  Estimated ammonia from pipe #2 0.002 MGD discharge and assumed ammonia cone, of 2 mg/L.
    m.  Design flow.
                                                                                             11
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
              MISSISSIPPI
                                                             ALABAMA
        	I HUC 8 Watersheds

            Streams

        *  Major BOD Dischargers

        •  Dams
                                                                        Miles
 Figure 3: Major Discharges of BOD to the Tombigbee River Above Aliceville Reservoir

Four major point  sources in the watershed, indicated  in red in Figure 3, contribute
oxygen-demanding wastes downstream  of Stennis Dam and upstream of Bevill Dam.
These four dischargers closer to Aliceville reservoir have a combined BOD limit of 4,846
pounds  per day and  an  ammonia limit of 692 pounds per day.   Monthly  discharge
monitoring report (DMR) data were obtained for Columbus POTW, Weyerhaeuser, EKA
Chemical and Sanderson.

The other eight of these major discharges are farther from Aliceville reservoir.  Seven are
upstream of Stennis Lock and Dam at Columbus and one is far upstream on Luxapallila
Creek.  These eight dischargers  have a total BOD limit of 5,884 pounds per day and an
ammonia limit  of 549 pounds per day. However, much of the distant discharged BOD
and nitrogen load is consumed or settled-out prior to reaching Aliceville Reservoir. The
loads from these facilities are a part of model boundary pollutant load conditions, and
these eight discharges are not explicitly  in the model. To understand the contribution to
the boundary pollutant load  from these  facilities, load estimations outside of the water
                                                                               12
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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
quality model were calculated. These estimations are based on distance from the model
boundary, flow velocity, and pollutant decay.

The BOD load delivered  to the Aliceville pool from the distant, eight dischargers  is
estimated to be about 33  percent of the  actual  discharged  load due to decay.  This
ultimately contributes only 1 percent of the total loading to the Aliceville reservoir.

These upstream major dischargers, as well as all minor permitted dischargers, are treated
as part of the headwater  background load  at Stennis Dam for modeling  purposes.
Existing  discharge data for the 12 major NPDES facilities in the watershed are included
in Table 5.

 Table 5: Existing Discharge (2003-2006) for Major NPDES Facilities to the Tombigbee
                         River Upstream of Aliceville Dam
Facility Name
Bryan Foods
True Temper
Sports/Emhart
Amory POTW
Aberdeen POTW
Hamilton POTW
West Point POTW
Tupelo POTW
Winfield POTW
Columbus POTW
Weyerhaeuser CPPC
EKA Chemical
Sanderson
Facility Type
Meat Packing
Plating
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Paper Mill
Chemical
Wood Products
5- day BOD
(Ibs/day)
51
78
108
188
25
66
584
22
245
2,659
32
3.3
Ammonia
(Ibs/day)
7
0.033
13
58
1.2
58
8
34
34
192
5.3
NA
TN
(Ibs/day)
1297
0
83
377
8
189
49
36
480
700
7.2
NA
TP
(Ibs/day)
598
14
54
32
64
17
353
5
65
191
7
NA
3.3    Data Availability and Analysis

A wide range  of data and information were used to characterize the watershed and the
instream conditions.  The categories of data used include physiographic data that describe
the  physical conditions of the watershed, environmental monitoring data that identify
potential pollutant sources and their contribution, and instream water quality monitoring
data.   This section presents  the  data  sources considered and their use  in  TMDL
development.


   3.3.1  Instream Water Quality

Water quality data from MDEQ,  ADEM, Environmental  Protection Agency Science and
Ecosystem Support Division (EPA SESD), and Weyerhaeuser Company was used to
characterize this reservoir and calibrate the models. A list of stations is shown in Table 6
and the locations are shown in Figure 4.
                                                                               13
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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
                Table 6: Water Quality Stations in Aliceville Reservoir
Station
1A
2A
3A
AVP01
AVP02
AVP03
CF025
JC315S
LC02
TT304
TT307
TT310
TT314
TT319
TT324
TT327
TT332
TT336
TT340
TTFA02S
327.8
327.0
316.3
308.1
1A
2A
Agency
ADEM
ADEM
ADEM
MDEQ
MDEQ
MDEQ
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
EPA
Weyerhaeuser
Weyerhaeuser
Weyerhaeuser
Weyerhaeuser
Weyerhaeuser
Weyerhaeuser
Station Name
Lower Aliceville Reservoir,
deepest point in main river
channel
Upper Aliceville Reservoir near
state line
Aliceville Reservoir Coal Fire
Creek Embayment
Aliceville pool at state line
Aliceville pool at Greens Creek
Aliceville pool below Luxapalilla
Creek
Coal Fire Creek
James Creek at Tenn-Tom
Waterway river mile 315.8
Luxapallila Creek near mouth
Tenn-Tom Waterway
downstream of Bevill Lock &
Dam
Tenn-Tom Waterway in Aliceville
Pool
Tenn-Tom Waterway near MS-
AL state line
Tenn-Tom Waterway near US 49
Bridge
Tenn-Tom Waterway near
Harrison Bend
Tenn-Tom Waterway below
Weyerhaeuser
Tenn-Tom Waterway above
Weyerhaeuser near marker buoy
Tenn-Tom Waterway near
Highway 82 Bridge
Columbus Pool nearStennis
Lock & Dam
Tenn-Tom Waterway near
Highway 50 Bridge
Tenn-Tom Waterway Flow
Augmentation Channel
Tenn-Tom at river mile 327.8
Tenn-Tom at river mile 327.0
Tenn-Tom at river mile 316.3
Tenn-Tom at river mile 308.1
ADEM station 1 A at Aliceville
Dam forebay
ADEM station 2A at state line
First Date
05/13/1992
04/19/2001
04/19/2001
06/24/2003
06/24/2003
06/24/2003
08/14/2005
08/13/2005
08/13/2005
08/15/2005
08/15/2005
08/15/2005
08/15/2005
08/13/2005
08/13/2005
08/13/2005
08/13/2005
08/11/2005
08/15/2005
08/11/2005
08/01/2003
08/01/2003
08/01/2003
08/01/2003
08/01/2003
08/01/2003
Last Date
10/31/2006
10/31/2006
10/31/2006
09/28/2004
11:30
09/28/2004
09/28/2004
08/16/2005
08/15/2005
08/15/2005
08/17/2005
08/17/2005
08/17/2005
08/17/2005
08/15/2005
08/15/2005
08/15/2005
08/15/2005
08/13/2005
08/17/2005
08/13/2005
1 0/24/2006
1 0/24/2006
1 0/24/2006
1 0/24/2006
10/24/2006
10/24/2006
#0bs
3,834
3,857
3,013
837
725
627
895
636
825
632
785
648
660
795
805
800
810
880
885
815
302
302
302
293
278
277
                                                                                   14
Prepared by US Environmental Protection Agency, Region 4

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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
   Figure 4: Model of Aliceville Reservoir showing water quality monitoring stations

Based on monitoring conducted by ADEM during the past 5 years, the DO measured at a
depth of five feet at Aliceville Dam sagged each summer and fell below the water quality
standard of 5 mg/L in 2003, 2004 and 2006. The DO farther upstream at the stateline
followed a similar cycle with a summer sag,  however it remained above 5 mg/L.   A
detailed analysis of available data is provided in the "Aliceville Reservoir Low DO
Modeling Report, July 2008" (Modeling Report).

   3.3.2  Other Available Data

Additional  data  sources were used to  set-up the models.  Sources  included USGS
topographic maps,  NHD area and waterbody  GIS coverages, and US Army Corps  of
Engineers shoreline coverages to define the model surface area and lay out the model
grid. Bathymetry for the Tombigbee River and Aliceville Reservoir collected by the US
Army Corps  of Engineers  and ADEM was used to define  channel  geometry for the
reservoir. Hourly flows from USGS gages downstream of Stennis Lock and Dam (USGS
02441390) and Bevill Lock and Dam (USGS 02444160), and daily flow for Luxapallila
Creek (USGS 2443500) were used to drive the hydraulics of the system.  Surface water
elevation of the  Aliceville  pool from the US Army Corps of Engineers was used  to
calibrate the EFDC model  and correct the flows.  The EFDC model volumes were also
compared to  US  Army Corps of Engineers  storage volume to elevation tables for
Aliceville Reservoir to make sure the model represented this relationship.

EFDC and WASP  require  climate data that includes air temperature, relative humidity,
precipitation, barometric pressure, solar radiation and cloud cover.  Climate data from the
Golden  Triangle Regional Airport (WBAN 53893) station near Columbus, MS was used
in the models.
                                                                             15
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Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
4.0    Model Development

Establishing the relationship between instream water quality and source loading is an
important component of TMDL development. It allows the determination of the relative
contribution of sources to total pollutant loading, the linkage of loads to ambient impacts,
and evaluation of potential  changes to water quality resulting from implementation of
various management options.  The linkage relationship for a TMDL can be developed
using a variety of techniques  ranging from qualitative assumptions based on scientific
principles  to  numerical computer modeling.   For  the  Aliceville  TMDL,  qualitative
assumptions and quantitative models were used.  This section describes the numerical
modeling techniques developed to simulate the loading of organic material and nutrients
and the resulting instream response of dissolved oxygen. Details on model calibration are
presented in the Modeling Report.

Two  significant  efforts have applied QUAL2E in the past  to  this  section  of the
Tombigbee River.  Based on comments received, the model was  redone to provide a
better representation of the reservoir.  The modeling supporting this TMDL included a 3-
D hydrodynamic model, a watershed loading model,  and an eutrophication water quality
model.
  4.1  Environmental Fluid Dynamics Code (EFDC)
Environmental Fluid Dynamics  Code  (EFDC)  was used to model  three dimensional
hydrodynamics for Aliceville reservoir. The hydrodynamic model was setup as 113 grid
cells to accurately represent the Aliceville Reservoir and Tombigbee River system. The
cell size varies, but each is approximately 760 meters long (half a mile) and 280 meters
wide with an average area  of 170,000 square meters.  The model cells are  shown in
Figure 4.  Each segment was subdivided into one to five vertical layers based on the
normal depth; so deeper pools are divided into five layers and shallow river segments are
represented as a single layer.  The EFDC model is used to simulate the dynamic flow and
water temperature from Stennis Lock and Dam  to Bevill Lock and Dam and  write this
information to a Water Quality Analysis  Simulation Program (WASP) hydrodynamic
input file. More  details about  the  development of this EFDC  model of Aliceville
Reservoir can be found in the report "Tombigbee River and  Aliceville Reservoir: Three
Dimensional Hydrodynamic Modeling Report" (Tetra Tech, 2007). This report covers
the initial setup and calibration of the Aliceville reservoir EFDC model for January 2003
through September 2005. For this TMDL, the EFDC model was expanded to include the
period to September 2006.

Through the hydrodynamic linkage file, the two  models are linked and WASP  computes
the water quality for each layer  of each EFDC cell. EFDC and WASP were setup for
about 32 miles of the Tombigbee Waterway from Stennis  Lock and Dam in Columbus,
Mississippi to the Aliceville Reservoir Pool impounded by Bevill Lock and Dam, in
Pickens, Alabama.   The  eutrophi cation module  of WASP is then used to  simulate
dissolved oxygen, nutrients, BOD and phytoplankton. The models were setup to simulate
the conditions from January 2003 to September 2006.  This period represents the current
Prepared by US Environmental Protection Agency, Region 4

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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
pollutant loads discharged from point and non-point sources. It also includes periods of
wet, normal and dry precipitation patterns, that influence dissolved oxygen dynamics.


  4.2  Water Quality Analysis Simulation Program (WASP)
The Water Quality Analysis Simulation Program (WASP) model was setup to evaluate
the effect of BOD, nutrients,  algae, and other  oxygen demanding substances on DO
processes.  The Water Quality Analysis  Simulation Program version 7 (WASP7)  is  an
enhancement of the original WASP (Di Toro et al., 1983; Connolly and Winfield, 1984;
Ambrose, R.B. et al.,  1988). This model helps users interpret and predict water quality
responses  to  natural  phenomena  and   man-made  pollution for various pollution
management  decisions.   WASP7  is  a  dynamic compartment-modeling program for
aquatic systems, including  both  the water  column and the underlying benthos.  The
time-varying  processes of advection,  dispersion, point and diffuse mass loading, and
boundary exchange are represented in the basic program.

Water quality processes  are represented in special kinetic  subroutines that are either
chosen from  a library or written  by the user.  WASP is structured to permit easy
substitution of kinetic subroutines into  the overall package to form  problem-specific
models.  WASP7 comes  with two such models  — TOXI for toxicants and EUTRO for
conventional  water quality.   Earlier versions of WASP have been used to examine
eutrophication of Tampa Bay; phosphorus loading to Lake Okeechobee; eutrophication of
the Neuse River and estuary; eutrophi cation and PCB pollution of the Great Lakes,
eutrophi cation of the  Potomac Estuary,  kepone pollution of the James River Estuary,
volatile organic pollution  of the Delaware Estuary, and heavy metal pollution of the Deep
River, North Carolina (Wool, et al., 2001).  In addition to these, numerous applications
are listed in Di Toro et al., 1983.

The flexibility afforded by  the Water Quality Analysis Simulation Program is unique.
WASP7 permits the modeler to structure one, two, and three-dimensional models; allows
the specification  of time-variable exchange coefficients, advective flows, waste loads and
water quality boundary conditions.  The eutrophi cation module of WASP7 was applied in
the development of these TMDLs.


  4.3  Past QUAL2E Model Applications to the  Tombigbee River
Two significant modeling efforts  have been  completed in the past on this section of the
Tombigbee River.  Both  of these efforts involved application  of QUAL2E, which is a
one-dimensional  steady-state modeling tool.  Data and information from these  models,
along with comments  from the public, were considered in developing the EFDC/WASP
model used for this TMDL.

The first application was undertaken by Weyerhaeuser in 1987-1989. The modeling was
initiated in support of a proposed expansion of the Weyerhaeuser Columbus Mississippi
facility from 6 to 26 MGD, conversion to a kraft process, and relocation of the discharge
from Cedar  Creek to the  Tennessee-Tombigbee waterway (Weyerhaeuser,  1988).
Weyerhaeuser collected  data during 1987,  including dye  studies for  travel time and
	17
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
measurements of sediment oxygen demand, and built and calibrated a QUAL2E model
for the Tombigbee River between Stennis Lock and Dam at Columbus, Mississippi and a
point 4 miles below Bevill Lock  and Dam  (Aliceville  Reservoir).   The calibration
appeared to yield an adequate fit to observed data. Because of the large load from the
proposed discharge and the low assimilative capacity of the river under summer low flow
conditions, the modeling was used to develop a  proposal for effluent limitations that
varied as a function of flow and temperature in the receiving water.

MDEQ and ADEM accepted the results of the Weyerhaeuser QUAL2E modeling and
MDEQ issued a NPDES permit to  Weyerhaeuser containing  the proposed  variable
effluent limitations.  EPA reviewed the permit in March of 1989 and submitted several
concerns.  These prompted some minor revisions to the model and a variety of additional
runs and sensitivity analyses (Weyerhaeuser,  1989). The final effluent limitations in the
Weyerhaeuser permit were based on the 1989 modeling.

Another QUAL2E modeling effort, covering the entire Tennessee-Tombigbee waterway,
was  conducted in the early 1990s.   The  Tombigbee  River upstream  of  Bevill  Dam,
including  Aliceville Reservoir,  is included in the Upper Tombigbee model (Shindala et
al., 1991).  A second model  was developed for the Tombigbee  from Aliceville  to
Gainesville, Alabama  (Homan et al.,  1995).  The Upper Tombigbee  model replaced
QUAL2E estimates of flow velocity  with a proprietary linkage to a HEC-2 model.
	 18
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
5.0   Development of Total Maximum  Daily Load

This  section presents the estimated TMDL developed  for  organic  enrichment and
dissolved oxygen for Aliceville Reservoir.  A TMDL is the total amount of a pollutant
that can be assimilated by the receiving water while still achieving water quality criteria,
in this case Alabama's water quality criteria for aquatic life. TMDLs can be expressed in
terms of mass per time or by other appropriate measures.  TMDLs are comprised of the
sum of individual wasteload allocations (WLAs) for point sources, load allocations (LAs)
for nonpoint sources, and natural  background levels.   In  addition,  the  TMDL must
include a margin of safely (MOS), either implicitly of explicitly, that accounts for the
uncertainty in the relationship between pollutant loads and the quality of the receiving
waterbody. Conceptually, this definition is denoted by the equation:

                         TMDL = Z WLAs + Z LAs + MOS

The TMDL is presented as a daily load in pounds of CBODu, TP and TN.

  5.1  Numeric Targets for TMDL
TMDL endpoints represent the instream water quality targets used in quantifying TMDLs
and their individual components.  For Aliceville Reservoir, the water quality target is
defined in terms  of  the Alabama  water  quality criterion for dissolved  oxygen.   As
discussed in Section 2.2, Alabama's water quality criteria state that,

       "for a diversified  warm water biota, including game fish, daily dissolved oxygen
       concentrations shall not be less than 5 mg/L at all times; except under extreme
       conditions  due to natural causes, it may  range between 5  mg/L  and 4 mg/L,
       provided that the  water quality is favorable in all other parameters.  The normal
       seasonal and daily fluctuations  shall be maintained above these levels... In the
       application of dissolved oxygen criteria referred to above, dissolved oxygen shall
       be measured at a depth of 5 feet in waters 10 feet or greater in depth; and for those
       waters less than 10 feet in depth, dissolved oxygen criteria will be applied at mid-
       depth."

In  Aliceville  Reservoir,  the most severe dissolved oxygen depletion is observed
immediately above Bevill Dam.  Water depth  here is greater than 10 feet; therefore, the
critical point  for application of the  dissolved oxygen  criterion is in the reservoir
immediately upstream of the dam, at a depth of 5 feet.

Critical conditions for application  of the  dissolved  oxygen criterion are provided in
Section 5.3. Meeting the 5  mg/L criterion under critical flow and temperature conditions
ensures that the criterion will  be met at all times throughout the year.

  5.2  Existing Conditions
The calibrated water quality model provides the basis for performing the TMDL analysis.
The first step in the analysis is the simulation of baseline conditions.  Baseline conditions
represent existing  nonpoint source and  NPDES  discharge  loading  conditions  and

	19
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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
permitted point source discharge conditions.  Table 7 below shows existing discharges
for the major NPDES permitted facilities upstream of Aliceville Dam.

         Table 7:  Existing Discharge (2003-2006) for Major NPDES Facilities
                            upstream of Aliceville Dam
Facility Name
Bryan Foods
True Temper
Sports/Emhart
Amory POTW
Aberdeen POTW
Hamilton POTW
West Point POTW
Tupelo POTW
Winfield POTW
Columbus POTW
Weyerhaeuser CPPC
EKA Chemical
Sanderson
Facility Type
Meat Packing
Plating
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Sewerage
Paper Mill
Chemical
Wood Products
5- day
BOD
(Ibs/day)
51
78
108
188
25
66
584
22
245
2,659
32
3.3
Ammonia
(Ibs/day)
7
0.033
13
58
1.2
58
8
34
34
192
5.3
NA
TN
(Ibs/day)
1297
0
83
377
8
189
49
36
480
700
7.2
NA
TP
(Ibs/day
)
598
14
54
32
64
17
353
5
65
191
7
NA
The  non-point  source  water quality loading from the  tributaries was  estimated with
BASINS PLOAD. Estimated BOD, nitrogen, and phosphorus loads for this section of the
Tombigbee River downstream of Stennis Dam at Columbus  are  shown  in  Table 8.
Details on how these values were calculated are included in the Modeling Report.
Table 8:
Estimated Nonpoint Source Loads from Stennis Dam to Bevill Dam
Parameter
BOD
TN
TP
Total Load in kg/year (and average Ibs/day)
1 ,225,874 (7404)
228,674(1381)
47,703 (288)

  5.3  Critical Conditions
As discussed in Section 2.2, Alabama's water quality criteria for Fish and Wildlife and
Swimming uses (ADEM Admin.  Code R. 335-6-10-.09-(5)(e)(4.) and Admin. Code R.
335-6-10-.09-(3)(c)(4.)) state that "for a diversified warm water biota, including game
fish, daily dissolved oxygen concentrations shall not be less than  5  mg/L at all times;
except under extreme conditions due to natural causes, it may range between 5 mg/L and
4 mg/L, provided that the water quality is favorable in all other parameters.  The normal
seasonal  and daily  fluctuations  shall  be maintained above  these levels... In the
application of dissolved oxygen  criteria referred to  above,  dissolved oxygen shall be
measured at a depth  of 5 feet in waters 10 feet or greater in  depth; and for those waters
less than  10 feet in depth, dissolved oxygen criteria will be applied at mid-depth."

The  critical conditions can be defined as  the environmental conditions requiring the
largest reduction to meet standards.  By  achieving the reduction for  critical  conditions,
water quality criteria should be achieved during all times.   The DO is lowest during
                                                                               20
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
summer conditions,  which  include low flows and  high temperatures.   The TMDL
addresses the worst summers in the 2003 through 2006 period.

Since Aliceville Reservoir is impaired for organic enrichment and low dissolved oxygen,
a number of processes that affect DO  needed to  be considered.  These include BOD
discharged directly from facilities, SOD from the accumulation of organic material over
long periods of time, excess primary production resulting from excess available nutrients,
and  aquatic  plant management activities.  Although low DO  occurs  during  high
temperature,  low flow conditions, when reaeration is minimal and retention times are
long, it should be kept in mind that this resultant low DO  lags introduction  of pollutants
in space and time. That fact must be considered when evaluating critical conditions. In
this case, the complex water quality issue was evaluated by simulating a four year period
containing  wet, normal, and  dry conditions.  Both wet  events and dry  events were
analyzed in this Jan. 2003 through Aug.  2006 period.

  5.4  Margin of Safety (MOS)
There  are two methods for incorporating  a Margin  of  Safety into a TMDL:  1) by
implicitly incorporating the MOS through use of conservative modeling assumptions in
the development of allocations, and 2) by explicitly  specifying a portion of the TMDL as
the MOS based on an analysis  of uncertainty in modeling results. The Aliceville TMDL
contains an implicit MOS that is obtained through  conservative modeling assumptions,
including addressing the worst case conditions in the four year period from 2003 through
2006.  In this TMDL the following information was considered in determining the margin
of safety.
          •   The worst case condition in the four year simulation from 2003 through
              2006 was addressed to meet standards.

          •   Decreases in loads throughout the watershed due to other approved
              TMDLs are expected to improve the DO at the model boundaries and
              decrease the pollutant loads at the model boundaries.

          •   The model demonstrates that implementation of the TMDL will result in
              average TN concentrations of 0.37 mg/L, which is less than the EPA
              recommended ambient water quality criteria recommendations for lakes
              and reservoirs in nutrient ecoregion IX (0.397 mg/L TN) (EPA, 1998).

  5.5  Seasonal Variation
Seasonal variation is incorporated into the TMDL development because the models were
setup to simulate the conditions  throughout each year from January 2003 to September
2006.  This period represents the current pollutant loads discharged from point and non-
point sources. It also includes  periods of wet, normal and  dry precipitation patterns that
influence dissolved oxygen dynamics.  Therefore, seasonal variation is incorporated into
the TMDL analysis  in a  manner that  ensures year-round  protection of water quality
standards.
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
  5.6  TMDL Results
In order to achieve the applicable water quality standards, the TMDL estimated by these
models requires a reduction of 30 percent from the total existing loads of CBODu, TN,
and TP that enter Aliceville Reservoir. The sources of CBODu, TN, and TP originate in
two states, Alabama  and Mississippi.  The TMDL is composed of three categories of
allocations: 1) a  wasteload allocation for the  point sources in Alabama; 2) a  load
allocation for the nonpoint sources in Alabama; and 3) an aggregate allowable pollutant
load, which includes both the point and nonpoint contributions, to Mississippi sources in
the Tombigbee River watershed at the state border (see sections 3.2.1 and 3.2.2. for more
information).

The category of the load allocation for Alabama nonpoint sources  is divided into two
subcategories to distinguish the nonpoint sources loads in Alabama that enter Mississippi
before ultimately draining back to Alabama across the state border.  The load allocation
to the  Coal Fire Creek watershed addresses nonpoint source loads that enter Aliceville
Reservoir without crossing  into or out of Mississippi.  The load allocation to all other
watersheds  within Alabama (i.e., the Bull Mountain,  Buttahatchee,  and Luxapillila
watersheds) address loads from Alabama that drain  into Mississippi before ultimately
draining back into Alabama across the state border.  In  addition, the Hamilton WWTP
and the  Winfield WWTP discharge to the Buttahatchee and Luxapillila  watersheds,
respectively; therefore, these wasteloads  also drain to Mississippi before ultimately
draining back into Alabama across the state border.  The distinction of Alabama loads
that enter Mississippi is important, because the aggregate allocation to pollutants from
Mississippi at the state border reflects some of the point and nonpoint source loads that
originate in Alabama.

Based  on an analysis  of the readily available data and information, the CBODu, TN, and
TP loads from the two existing point source facilities in Alabama (i.e., Hamilton WWTP
and Winfield WWTP) are determined not to have an impact on water quality in Aliceville
Reservoir.   This determination is  made in consideration of the magnitude of the loads
from these facilities,  the  fate and transport of such loads from the  significant distance
upstream from  Aliceville  Reservoir, and analysis of  water  quality  data  in  the
Buttahatchee Creek and Luxapalliala Creek watersheds. Therefore, these facilities are not
subject to the wasteload allocation.

The  aggregate  allocation  to  Mississippi  reflects  the  allowable  loads   at  the
Alabama/Mississippi  border, rather than the allowable loads at their point of origin.  The
loads  and  wasteloads upstream from the state border within  both Mississippi and
Alabama will  experience fate  and transport processes through settling,  decay, and
assimilation in the upstream waters  before  entering Aliceville Reservoir; therefore, the
sum of the loads from the point  and  nonpoint sources  entering  the watershed will be
greater in magnitude  than the loads draining from Mississippi into Alabama at the state
line.

Although Aliceville Reservoir is not specifically  identified  as impaired for  nutrients on
Alabama's § 303(d) list, reductions to TP and TN are necessary to meet a minimum DO
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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
concentration of 5 mg/L.  Based upon information currently available, the reductions and
associated  allocations  for  TP  and  TN  are  not expected  to  cause or contribute to
excursions of water quality standards to any downstream waterbodies.

Table 9  shows  the maximum  daily  loads that  will  meet and  maintain water  quality
standards  during the  critical  conditions experienced each summer (June - September).
Loads for non-summer months can be higher than those in , as long as the annual average
does not exceed the allocations in Table  10.
Table 9: OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville Reservoir
                                        (June - September)
Pollutant
CBODu
TN
TP
ALABAMA
Coal Fire Creek
Watershed
(HUC 3160106) 1'5
LA
30% reduction
(1,200lbs/day)
30% reduction
(17lbs/day)
30% reduction
(4 Ibs/day)
All other watersheds
(HUC 03160101, 03160103, and
03160105) 2'5
WLA
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
LA
30% reduction
30% reduction
30% reduction
MISSISSIPPI
Aggregate allocation to
pollutants from
Mississippi at the state
border5
30% reduction
(83,956 Ibs/day)
30% reduction
(9,606 Ibs/day)
30% reduction
(1,663 Ibs/day)
TMDL4
30% reduction
(85, 156 Ibs/day)
30% reduction
(9,623 Ibs/day)
30% reduction
(1,667 Ibs/day)
    The Coal Fire Creek watershed (HUC 03160106) is the only watershed in the Alabama portion of the Tombigbee River basin
    that does not drain into Mississippi; therefore, loads from this watershed are not reflected in the aggregate allocation to
    Mississippi.
    All other watersheds in Alabama (Bull Mountain Creek (03160101), Buttahatchee Creek (03160103), and Luxapallila Creek
    (03160105)) drain from Alabama to Mississippi before ultimately draining back to Alabama and into Aliceville Reservoir. The
    only point sources in Alabama discharge to these watersheds.
    The wasteload allocation of 0 Ibs/day recognizes that there are currently no point sources in Alabama that impact dissolved
    oxygen levels in Aliceville Reservoir. In order to be consistent with this wasteload allocation, any potential future discharges in
    Alabama can only discharge TN, TP, or CBODu loads within the Basin if they are determined to not have any impact on the
    dissolved oxygen levels in Aliceville Reservoir.
    The TMDL is calculated by adding the aggregate allocation at the Mississippi border to the LA for the Coal Fire Creek
    watershed. The WLA to the Alabama point sources and the LA to the other Alabama watersheds were not added in the TMDL
    calculation, because their allocations are already reflected in the aggregate allocation to Mississippi.
    Pollutant trading may occur between the loads allocated to nonpoint sources in Alabama and Mississippi if: (1) MDEQ and
    ADEM agree to trade; and (2) such trading results in an overall 30% reduction of CBODu/TN/TP loads to Aliceville reservoir.
                                                                                                  23
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Tombigbee River (Aliceville Reservoir)
FINAL - Organic Enrichment/Dissolved Oxygen
 Table 10:  OE/DO TMDLs and Reductions Necessary to Meet WQS in Aliceville Reservoir
                                           as an Annual Average
Pollutant
CBODu
TN
TP
ALABAMA
Coal Fire Creek
Watershed
(HUC 3160106) 1'5
LA
30% reduction
(2,600 Ibs/day)
30% reduction
(29 Ibs/day)
30% reduction
(6 Ibs/day)
All other watersheds
(HUC 03160101, 03160103, and
03160105) 2'5
WLA
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
0% reduction
(0 Ibs/day)3
LA
30% reduction
30% reduction
30% reduction
MISSISSIPPI
Aggregate
allocation to
pollutants from
Mississippi at the
state border 5
30% reduction
(181, 952 Ibs/day)
30% reduction
(16,311 Ibs/day)
30% reduction
(2,633 Ibs/day)
TMDL4
30% reduction
(184,552 Ibs/day)
30% reduction
(16, 340 Ibs/day)
30% reduction
(2,639 Ibs/day)
     The Coal Fire Creek watershed (HUC 03160106) is the only watershed in the Alabama portion of the Tombigbee River basin
     that does not drain into Mississippi; therefore, loads from this watershed are not reflected in the aggregate allocation to
     Mississippi.
     All other watersheds in Alabama (Bull Mountain Creek (03160101), Buttahatchee Creek (03160103), and Luxapallila Creek
     (03160105)) drain from Alabama to Mississippi before ultimately draining back to Alabama and into Aliceville Reservoir. The
     only point sources in Alabama discharge to these watersheds.
     The wasteload allocation of 0 Ibs/day recognizes that there are currently no point sources in Alabama that impact dissolved
     oxygen levels in Aliceville Reservoir. In order to be consistent with this wasteload allocation, any potential future discharges in
     Alabama can only discharge TN, TP, or CBODu loads within the Basin if they are determined to not have any impact on the
     dissolved oxygen levels in Aliceville Reservoir.
     The TMDL is calculated by adding the aggregate allocation at the Mississippi border to the LA for the Coal Fire Creek
     watershed.  The WLA to the Alabama point sources and the LA to the other Alabama watersheds were not added in the TMDL
     calculation, because their allocations are already reflected in the aggregate allocation to Mississippi.
     Pollutant trading may occur between the loads allocated to nonpoint sources in Alabama and Mississippi if: (1) MDEQ and
     ADEM agree to trade; and (2) such trading results in an overall 30% reduction of CBODu/TN/TP loads to Aliceville reservoir.
                                                                                                             24
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
6.0   Conclusions

The allocations described in this TMDL report will ensure protection of the applicable
water  quality standards  in Aliceville Reservoir.  The State  of Alabama is  strongly
encouraged to continue proceeding with the development of numeric nutrient criteria for
all  waters  of the State, including  Aliceville Reservoir.  As part of this process,  EPA
recommends that ADEM coordinate with MDEQ in conducting studies in order to verify
the allocations in the TMDL.

ADEM and  MDEQ, through their NPDES permitting processes and nonpoint source
management programs, are strongly encouraged to  develop  a plan to implement the
TMDL.  40 CFR §  122.44(d)(l)(vii)(B) requires that NPDES permits should ensure that
water  quality-based effluent  limitations  are  consistent  with  the assumptions  and
requirements of any applicable  TMDL.  MDEQ is encouraged to use the water quality
models referenced in this report  and any additional data and information to implement the
aggregate allocation assigned at the Alabama/Mississippi border in a manner that ensures
compliance with 40 CFR § 122.44(d)(l)(vii)(B) and Alabama's applicable water quality
standards as expressed in this TMDL.

It is recommended  that the Aliceville Reservoir watershed be considered a priority for
riparian buffer zone restoration  and other nutrient reduction BMPs. The implementation
of these  BMP activities should  significantly reduce the nutrient load entering the river.
These  activities, coupled  with establishing  appropriate  water  quality  based  limits
consistent with the TMDL, will  provide improved water quality for the support of aquatic
life in  the water bodies and should ensure the attainment of the applicable water quality
standards.  As part of this process, MDEQ is encouraged to consider TN, TP, and CBOD
reductions identified in other TMDLs that it previously established for impaired waters in
the Tombigbee River basin.
	25
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
7.0   Public Participation

This TMDL was proposed for public review and comment for a 90-day period, beginning
October 31, 2007. EPA distributed information regarding the public notice of the TMDL
by e-mail to members of the public who have requested that ADEM and MDEQ include
them on a TMDL mailing list.  The draft TMDL document was also available for review
on EPA Region 4's website: (http://www.epa.gov/Region4/water/tmdl/Alabama/).

All comments received during the public notice period are a part of the public record for
this TMDL. EPA has fully considered these comments as described in a responsiveness
summary, which is also part of the public record.

EPA  acknowledges and  appreciates  the  all  of the  comments, data,  and information
provided by the members of the public, which added significant value  to the process of
establishing this TMDL.
	 oo
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 Tombigbee River (Aliceville Reservoir)         FINAL - Organic Enrichment/Dissolved Oxygen
8.0   References

Ambrose Jr., R.B., Wool, T.A., Connolly, J.P., and R.W. Schanz. 1988. WASP4, A
       Hydrodynamic and Water Quality Model-Model Theory, User's Manual, and
       Guide. U.S. Environmental Protection Agency. Environmental Research
       Laboratory, Athens, GA. EPA/600/3-87/039.

Banks, R.B. 1975.  Some features of wind action on shallow lakes. Am. Soc. Civil Eng.,
       J. Environ. Eng. Div., 101(EE5): 813-827.

Banks, R.B. and F.F. Herrera. 1977. Effect of wind and rain on surface reaeration. Am.
       Soc. Civil Eng., J. Environ. Eng. Div., 103(EE3): 489-504.

Brown, L.L. and T.O. Barnwell, Jr. 1987. The Enhanced Stream Water Quality Models
       QUAL2E and QUAL2E-UNCAS: Documentation and User Manual.  EPA/600/3-
       87/007. Environmental Research Laboratory, U.S. Environmental Protection
       Agency, Athens, GA.

Connolly, J.P. and R. Winfield. 1984.  A User's Guide for WASTOX, a Framework for
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       600/3-84-077.

Di Toro, D.M., Fitzpatrick, J.J., and R.V. Thomann. 1981, rev. 1983. Water Quality in
       Large Lakes, Part 1: Lake Huron andSaginaw Bay. EPA-600/3-80-056.

EPA. 1997. Technical Guidance Manual for Developing Total Maximum Daily Loads,
       Book 2: Streams and Rivers, Part 1:  Biochemical Oxygen Demand/Dissolved
       Oxygen and Nutrients/Eutrophication. EPA 823-B-97-002. United States
       Environmental Protection Agency, Office of Water.

EPA. 1998. National Strategy for the Development of Regional Nutrient Criteria. EPA-
       822R98002. June, 1998.

EPA. 2008. Aliceville Reservoir Dissolved  Oxygen TMDL Model Report. United States
       Environmental Protection Agency, Region 4. July 2008.

Homan, S.W., D.W. Spivey, E.J. Brandt, J.M. Morgan, and  S.R. Jenkins. 1995. A Water
       Quality Model Validation for the Tennessee-Tombigbee Waterway: Aliceville to
       Gainesville. Prepared for Tennessee-Tombigbee Waterway Development Council
       by Alabama Water Resources Research Institute and Auburn University
       Department of Civil Engineering, Auburn, AL.

Riggs, H.C. 1972. Low-Flow Investigations. Book 4, Chapter Bl of Techniques of Water
       Resources Investigations of the USGS. U.S.  Geological Survey, Washington, DC.
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Shindala, A., D.D. Truax, and K.R. Jin. 1991. Development of a Water Quality Model for
       the Upper Tennessee-Tombigbee Waterway.  Submitted to the Tombigbee River
       Valley Water Management District by Water Resources Research Institute,
       Mississippi State University, Mississippi State, MS.

Tetra Tech. 2007. Tombigbee River and Aliceville Reservoir: Three Dimensional
       Hydrodynamic Modeling Report.  Prepared by Tetra Tech under contract to the
       USEPA Region 4.  June 7, 2007.

Thomann, R.V. and J.A. Mueller. 1987.  Principles of Surface Water Quality Modeling
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Truax, D.D. and A. Shindala.  1995. Comparison of two sediment oxygen demand
       measurement techniques. Journal of Environmental Engineering, 121(9): 619-
       624.

USGS. 1991. Low-Flow and Flow-Duration Characteristics of Mississippi Streams,
       Water-Resources Investigations Report 90-4087.

USGS. 1995. Low-Flow and Flow-Duration Characteristics of Alabama Streams, Water-
       Resources Investigations Report 93-4186.

Weyerhaeuser. 1988. QUAL2E Model of the Tombigbee River below Stennis Lock and
       Dam. Notebook submitted to Mississippi Bureau of Pollution Control by
       Weyerhaeuser Paper Company, Columbus, MS, March 10, 1988.

Weyerhaeuser. 1989.  QUAL2E Modeling Review. Notebook submitted to Mississippi
       Bureau of Pollution Control by Weyerhaeuser Paper Company, Columbus, MS,
       May 12, 1989.

Whittemore, R. and J. McKeown. 1978. Interfacial Velocity Effects on Measurement of
       Sediment Oxygen Demand. NCASI Technical Bulletin No. 317.

Wool, Tim  A., Robert B. Ambrose, James L. Martin, and Edward A. Comer, 2001. 2001,
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       Manual, U.S. Environmental Protection Agency - Region 4 Atlanta, GA.
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