FINAL
Mixing Zone Dilution Modeling for Six Alaska POTWs
Prepared for:
United States Environmental Protection Agency
Cincinnati Procurement Operations Division
Cincinnati, Ohio 45268
USEPA OW Contract: 68HERC20D0010; Task Order: 68HERV21F0114
Technical Support for National Pollutant Discharge
Elimination System (NPDES), Clean Water Act Section 301(h),
and Endangered Species Act Section 7 Implementation
in EPA Region 10 NPDES Permits Section
Prepared by:
GleC
Great Lakes Environmental Center
739 Hastings St.
Traverse City, MI 48686
Contact: Douglas Endicott
Phone: (231)941-2230
Email: dendicott@glec.com
www.glec.com
Date: August 5, 2021
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table of Contents
Table of Contents ii
List of Tables ii
List of Figures ii
Mixing Zone Dilution Modeling for Six Alaska POTWs 1
Haines 8
Ketchikan 15
Petersburg 23
Sitka 28
Skagway 35
Wrangell 42
Summary 47
References 50
Appendix: VP and FARFIELD Output for Each Location 51
No. of Pages
Appendix: VP and FARFIELD Output for Each Location 52
List of Tables
Table 1. Maximum Effluent FC Concentrations Based on EPA (1991) Reasonable Potential Procedure
(Maximum Monthly Concentrations Reported in DMRs Over the Past 5 Years) 2
Table 2. Summary of Data Used for Mixing Zone Dilution Modeling 5
Table 3. Haines mixing zone dilution modeling results 11
Table 4. Ketchikan Mixing Zone Dilution Modeling Results 18
Table 5. Petersburg Mixing Zone Dilution Modeling Results 25
Table 6. Sitka Mixing Zone Dilution Modeling Results 31
Table 7. Skagway Mixing Zone Dilution Modeling Results 38
Table 8. Wrangell Mixing Zone Dilution Modeling Results 44
Table 9. Average Dilution Factor Predictions at Distances from the Discharge Point Corresponding to 1-
10 Times the Depth of Discharge 47
Table 10. Average Dilution Factor Predictions at the Distance from the Outfall to Shore 47
Table 11. Dilution Factor Predictions at Distances Equal to Initial Mixing Region Boundaries 48
Table 12. Dilution Factors and Mixing Zone Distances Required to Attain FC Criteria 49
List of Figures
Figure 1. Aerial View of the POTW Outfall Location at Haines 8
Figure 2. Vertical Ambient Profile of Temperature, Salinity and Density in Haines Mixing Zones
Resulting in Least Mixing 9
Figure 3. Haines Discharge Plume Boundary Plan View from Above 14
Figure 4. Haines Discharge Plume Centerline and Boundary Profile View from Side 14
Figure 5. Haines Discharge Plume Average and Centerline Dilution vs. Distance from Outfall 14
Figure 6. Aerial View of the POTW Outfall Location at Ketchikan 15
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Figure 7. Vertical Ambient Profile of Temperature, Salinity and Density in Ketchikan Mixing Zone
Resulting in Least Mixing 16
Figure 8. Ketchikan Discharge Plume Boundary Plan View from Above 21
Figure 9. Ketchikan Discharge Plume Centerline and Boundary Profile View from Side 21
Figure 10. Ketchikan discharge plume average and centerline dilution vs. distance from outfall 22
Figure 11. Aerial View of the POTW Outfall Location at Petersburg 23
Figure 12. Vertical Ambient Profile of Temperature, Salinity and Density in Petersburg Mixing Zone
Resulting in Least Mixing 24
Figure 13. Petersburg Discharge Plume Boundary Plan View from Above 27
Figure 14. Petersburg Discharge Plume Centerline and Boundary Profile View from Side 27
Figure 15. Petersburg Discharge Plume Average and Centerline Dilution vs. Distance from Outfall 27
Figure 16. Aerial View of the POTW Outfall Location at Sitka 28
Figure 17. Vertical Ambient Profile of Temperature, Salinity and Density in Sitka Mixing Zone Resulting
in Least Mixing 29
Figure 18. Sitka Discharge Plume Boundary Plan View from Above 33
Figure 19. Sitka Discharge Plume Centerline and Boundary Profile View from Side 33
Figure 20. Sitka Discharge Plume Average and Centerline Dilution vs. Distance from Outfall 34
Figure 21. Aerial View of the POTW Outfall Location at Skagway 35
Figure 22. Vertical Ambient Profile of Temperature, Salinity and Density in Skagway Mixing Zone
Resulting in Least Mixing 36
Figure 23. Skagway Discharge Plume Boundary Plan View from Above 41
Figure 24. Skagway Discharge Plume Centerline and Boundary Profile View from Side 41
Figure 25. Skagway Discharge Plume Average and Centerline Dilution vs. Distance from Outfall 41
Figure 26. Aerial View of the POTW Outfall Location at Wrangell 42
Figure 27. Vertical Ambient Profile of Temperature, Salinity and Density in Wrangell Mixing Zone
Resulting in Least Mixing 43
Figure 28. Wrangell Discharge Plume Boundary Plan View from Above 46
Figure 29. Wrangell Discharge Plume Centerline and Boundary Profile View from Side 46
Figure 30. Wrangell Discharge Plume Average and Centerline Dilution vs. Distance from Outfall 46
Figure 31. DF Predictions Graphed as a Function of Distance from the Outfall 48
Hi
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Mixing Zone Dilution Modeling for Six Alaska POTWs
For each of the six POTWs of interest in southeast Alaska (Haines, Ketchikan, Petersburgh, Sitka,
Skagway, and Wrangell) mixing zone dilution models were developed and applied to predict the steady-
state dilution of effluent being discharged into the marine coastal receiving waters. Because of the nature
of the discharges and receiving waters, initial dilution models within the EPA-approved Visual Plumes
software (EPA 2003) were selected for use. From a modeling perspective, each of the receiving water
mixing zones share several important characteristics that led to the selection of Visual Plumes, as opposed
to the alternative EPA-approved modeling framework, CORMIX:
Discharge of buoyant effluent into a deep (20-30 meter), stratified marine water body;
No shoreline boundaries within 100 meters of the outfalls;
Relatively small discharge flow rates (0.6-7 MGD); and
No obstructions in the receiving waters to impede circulation near the outfalls, making tidal
build-up of pollutants unlikely.
For each site, appropriate models were applied to predict average dilution at various distances
(corresponding to 1-10 times the depth of discharge) from the discharge point, as well as the geometry
(depth, width, etc.) of the plume itself. Aquatic life-based mixing zone analyses involve the concept of
determining reasonable worst-case values for various parameters because the durations established for
these water quality criteria vary for both acute and chronic toxicities (Washington DoE, 2018). The term
reasonable worst-case refers to the value selected for a specific effluent or receiving water parameter.
Critical conditions refer to a scenario involving reasonable worst-case parameters, which has been set up
to run in a mixing zone model. For this work, steady-state mixing zone models were applied using a
combination of parameters (e.g., effluent flow, current speed, density profile) to simulate critical
conditions. The predictions were based on input data representing critical conditions demonstrated to
minimize the dilution of effluent pollutants. It should be understood that each critical condition (by itself)
has a low probability of occurrence.
It should also be understood that mixing zone modeling is not an exact science (Reese et al., 2021). With
limited data and numerous variables, mixing zone sizes may be considered best estimates to ± 50%.
Sensitivity analysis and comparison of alternative models were used to develop confidence in the dilution
model predictions. All simulations explicitly included fecal coliform (FC) as a pollutant, which required
the models to simulate bacterial decay in the receiving waters. Maximum effluent (end-of-pipe) FC
concentrations were estimated for modeling by applying the EPA (1991) reasonable potential procedure
to maximum monthly concentrations reported over the past five years in Discharge Monitoring Reports
(DMRs) provided by EPA Region 10. The maximum effluent FC concentrations for each discharge are
presented in Table 1 along with the dilution factors required to meet the Alaska marine water quality
standards for harvesting for consumption of raw mollusks or other raw aquatic life (18 AAC 70 Water
Quality Standards, amended as of March 5, 2020):
The geometric mean of samples may not exceed 14 fecal coliform/100 ml, and not more than 10% of the
samples may exceed 43 MPN per 100 mL for a five-tube decimal dilution test.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 1. Maximum Effluent FC Concentrations Based on EPA (1991) Reasonable Potential
Procedure (Maximum Monthly Concentrations Reported in DMRs Over the Past 5 Years)
City
Haines
Kechikan
Petersburg
Sitka
Skagway
Wrangell
Maximum expected
effluent FC (daily
2,100,000
2,900,000
2,000,000
3,700,000
2,600,00
190,000
max, 99%; n/100 mL)
Dilution factor1
required to meet
14/100 mL FC
150,000
210,000
140,000
270,000
190,000
14,000
criterion
Dilution factor
required to meet
43/100 mL FC
50,000
67,000
47,000
87,000
60,000
4,400
criterion
Model predictions of the size of the mixing zones required to attain these dilution factors are presented in
the summary of this report.
Most mixing zone simulations required the combination of initial dilution and far-field models. Initial
dilution models simulate the "initial mixing region" or "hydrodynamic mixing zone" defined to end
where the self-induced turbulence of the discharge collapses under the influence of ambient stratification
and initial dilution reaches its limiting value (EPA, 1994). At the end of this region/zone the waste field is
established and then drifts with the ocean currents and is diffused by oceanic turbulence.
The initial dilution models included UM3, DKHW and NRFIELD, all contained within the Visual Plumes
(VP) framework. Although the three initial dilution models run under the same VP interface, they differ in
terms of origin and development, underlying assumptions, empirical datasets, solution techniques and
coding. UM3 is a three-dimensional Updated Merge (UM) model for simulating single and multiport
submerged diffusers. DKHW is an acronym for the Davis, Kannberg and Hirst model, a three-
dimensional model for submerged single or multi-port diffusers. DKHW is limited to positively buoyant
plumes and considers either single or multiport discharges at an arbitrary horizontal angle into a stratified,
flowing current. NRFIELD is based on the Roberts, Snyder and Baumgartner (RSB) model, an empirical
model for multiport diffusers (T-risers, each having two ports for a total of 4-ports) in stratified currents.
A shortcoming of each of these initial dilution models in VP is their inability to recognize and address
lateral boundary constraints, although that is not a major issue for these Alaskan mixing zone sites.
Although the original 2001 version of VP is still available from EPA's CEAM site, it is currently
unsupported and known to contain a number of errors (Frick et al. 2010; Frick and Roberts, 2019). We
instead used the updated VP version 20, maintained and distributed by the California State Water
Resources Control Board, Ocean Standards Unit (https://ftp.waterboards.ca.gov).
The Brooks far-field model was used to extend dilution simulations beyond the spatial bounds of initial
dilution. Although this model is incorporated in VP, we also used a stand-alone spreadsheet version of the
1 Dilution Factor, DF = (end of pipe) concentration/mixed concentration.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brooks model, FARFIELD, that is contained in the Washington Department of Ecology (DoE), Permit
Calculation workbook (https://ecology.wa.gov/Regulations-Permits/Guidance-technical-assistance/Water-
quality-permits-guidance). FARFIELD calculates dilution using the method of Brooks (1960) and is
recommended by Frick et al. (2010) in lieu of using far-field predictions within VP, since the latter does
not allow for the use of linear diffiisivity as recommended in estuaries. FARFIELD was used to double-
check the far-field results in VP, and in some instances to replace them.
The initial dilution models relied upon a variety of data to characterize the effluent, discharge outfall and
receiving water. These data are summarized in Table 2. The data were gathered from a number of sources
including EPA Region 10 and the State of Alaska; from the permittees as documented in permit files, as-
built drawings and charts, etc.; tidal current predictions made by the National Oceanic and Atmospheric
Administration (NOAA); and other literature sources found by Internet search.
All six of the POTWs discharge effluent using deeply-submerged outfalls with diffusers and multiple
ports (Table 2). Haines and Petersburg both use two-diffiiser ports, while the others use multiport
diffusers with 6 to 16 ports. Modeling initial dilution from the four sites using multiport diffusers required
additional considerations, because these diffusers have opposing ports (ports on both sides of the diffuser
pipe that discharge effluent into opposite directions), creating co-flowing and counter-flowing plumes.
Counter-flowing plumes are discharged opposing the ambient current and will generally rise and bend
back into the direction from whence they came, eventually merging with the co-flowing plumes that are
discharged on the opposite side of the pipe in the direction of the current. This is called cross-diffuser
merging (EPA, 2003). Two alternative modeling approaches were applied to simulate initial mixing from
opposing ports in the UM3 and DKHW models (NRFIELD models cross-diffuser merging directly). The
first approach ("half spacing") treated the diffuser as if all ports are on one side with half the spacing. In
the context of merging plumes, this approach works well when the distances of interest are somewhat
beyond the point of merging.
The second approach ("downstream only") involves simulating only downstream ports. This necessitates
doubling the flow per port (assuming there is an even number of ports in the diffuser) and increasing the
diameter of the ports to maintain approximately the same densimetric Froude number. With this approach
only the downstream ports would be used when determining spacing and number of ports. The
Washington DoE Permit Writer's Manual, Appendix C (2018) discusses the merits of these approaches.
When possible, we applied both approaches to modeling cross-diffuser merging and compared the results.
We assumed that all ports on a multiport diffuser discharged effluent flow equally and at the same depth.
The multiport diffuser at Ketchikan was unique because it was the only diffuser that combined ports of
different sizes. Five 6-inch opposing ports were spaced along a 12-inch manifold, and a sixth 12-inch port
was located at the manifold's end. The CORMIX hydraulic module CorHyd (MixZone, 2020) was used to
determine the flow distribution between the 6-inch ports and the 12-inch port. At a nominal flow rate of
5.35 MGD, CorHyd calculated that the 6-inch ports would discharge 52% of the flow, and the remaining
48% would be discharged from the 12-inch port. These same percentages were applied to other flow rates
at Ketchikan. Initial model simulations suggested that the plumes emanating from the 12-inch port would
not merge with the plume from the other ports, due to the 90° difference in port orientations. Therefore,
these plumes were modeled separately.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
The diffuser port orifice contraction coefficient is an initial dilution model hydraulic parameter that is
specified according to how ports are machined in the diffuser pipe wall (EPA, 2003). For all of the
outfalls except Sitka, sharp-edged ports were assumed, and contraction coefficients of 0.61 were
specified. For Sitka, the port orifices were bell-shaped, so a contraction coefficient of 1.0 was applied.
Tidal current predictions were used to calculate 10th percentile and average current velocities at each site.
The tidal prediction location nearest each discharge site was identified and tidal velocity predictions for
2021 were downloaded from the NOAA Tides & Currents web site (http://tidesandcurrents.noaa.gov).
These data were imported into a spreadsheet and the predictions for the month in which the critical
ambient conditions fell were selected. For Haines, Ketchikan and Skagway, 6-minute tidal velocity
predictions were available. The tenth percentile of the absolute value of these velocities were calculated
and used as the critical ambient velocity input for mixing zone dilution modeling. For the other locations,
only times and velocities for ebb, slack and flood tides were available. The Excel FORECAST function
was then used to interpolate hourly values from the tidal velocity predictions, and the tenth percentile of
the absolute value of these interpolated hourly values was calculated and used for modeling2. These
velocities, ranging from 1.4 to 5.9 cm/s, are presented in Table 2. The compass directions of tidal currents
(also presented in Table 2) were based on the tidal current predictions, the orientation of the nearest
shoreline (presuming currents to flow parallel to the shoreline), and other information from the permit
files. The average hourly ebb and flood tidal velocities were calculated similarly and are also presented in
Table 2 and were used in the model sensitivity analysis.
The decay of fecal coliform was included in the initial dilution and far-field models by using the Mancini
(1978) bacteria model that incorporates four variables (salinity, temperature, solar insolation, and water
column absorption) to determine the rate of first-order decay. Summertime solar insolation in southeast
Alaska was based upon the models and measurements of Dissing and Wendler (1998). Summertime solar
radiation flux, that takes into account both latitude and fractional cloud cover, averaged 190 Watts/m2
(16.3 Langleys/hr) in the Alexander Archipelago. The bacterial decay model used ambient water
temperature and salinity, and a default light absorption coefficient of 0.16, to calculate decay rates of
~0.0002/d. Decay of fecal coliform was found to be insignificant in comparison to physical dilution at the
time and space scales of interest for mixing zone analysis.
2 Comparison between linear interpolation and cubic spline interpolation of the tidal velocity predictions suggests
that linear interpolation may yield average velocities that could be low by a factor of 1.6 to 2.3. The impact of this
discrepancy on DF predictions will be demonstrated via sensitivity analysis.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 2. Summary of Data Used for Mixing Zone Dilution Modeling
City
Haines
Ketchikan
Petersburg
Sitka
Skagway
Wrangell
Permit
AK0021385
AK0021440
AK0021458
AK0021474
AK0020010
AK0021466
DMR data available
2011-2020
2013-18
2015-2019
2015-20
2007-19
2007-19
DMR data used
2016-2020
2013-2018
2015-2019
2015-2020
2014-2019
2015-2019
Permit Maximum Flow
Rate (MGD3)
2.9
7.2
3.6
5.3
0.63
3.0
monthly4 average
effluent temperature
12.0
14.65
13.2
14.0
14.7
17.3
monthly maximum
effluent temperature
15.8
20.5
14.6
15.0
17.3
18.4
Outfall
distance from shore (m)
549
221
366
114
125
457
depth at LWWD (m)
21.3
29.9
18.3
24.4
18.3
30.5
number of diffuser
ports
2 (3rd is capped)
6
2
(3 others capped)
16 bell-shaped
8
16
diffuser length (ft)
30
190
45.9
195
25
240
port diameter (in)
3
5@6", 1@12"
4
4
3
3
Elevation of ports
above bottom (in)
8
12
9
18
6
6
Port spacing (ft)
15-306
40
(20' apart on
alternating sides of
pipe)
10-346
26 (13' apart on
alternating sides
of pipe)
7
32 (16' apart
on alternating
sides of pipe)
Port orientation
horizontal
horizontal
(opposing/
alternating) +
diffuser end
horizontal
horizontal
opposing/
alternating
horizontal
opposing
horizontal
opposing/
alternating
3 Million gallons per day.
4 Average effluent temperature for month of limited dilution
5 Average of maximum monthly effluent temperatures (no monthly averages in DMR)
6 Port spacing is uncertain given information in permit fact sheet.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
City
Haines
Ketchikan
Petersburg
Sitka
Skagway
Wrangell
VP discharge angle7
(degrees)
90
115 (5x6" ports),
205 (1x12" port)
115
300
350
90
Receiving Water
Water body
Portage Cove,
Chinook Inlet
Tongass Narrows,
Charcoal Point
Frederick Sound
Sitka Sound,
Middle Channel
Tiaya Inlet
Zimovia Strait
tidal range (ft)
14.2
13
15
7.7
14.1
13
data source/file8 name
for ambient data
NA; used
Skagway data
AK0021440_Ketch
ikantempsalinity
PetersburgRecei
ving Water Data
Sitka Receiving
Water
Monitoring
Table 2-5 v2
Wrangell FC
and RW
Monitoring
Ambient salinity/temp
profile limiting dilution
Skagway site 1,
June 2005
Ketchikan site 3,
July 1997
Petersburg site 1,
August 2005
Sitka site C,
July 2010
Skagway site 1,
June 2005
Wrangell site 4,
August 2016
NOAA tides & current
predictions
Battery Point,
Chinook Inlet
(SEA0826)
East of Airport
(SEA0711)
Cosmos Point
(PCT3811)
Sitka Harbor,
Channel off
Harbor Island
(PCT4166)
Tiaya Inlet
(SEA0825)
Wrangell
Harbor
(PCT3131)
Tidal current 10th
percentile (cm/s)
June: 2.1 @ 35',
2.8 @ 133'; 2.3
(interpolated to
discharge depth)
July: 5.9 @87'
August: 1.6
July: 1.7
June: 1.4 @37'
August: 4.0
Tidal current average
(Ebb/Flood, cm/s)
June: 10.2/10.7 @
35', 11.3/16.1 @
133'; 10.5/12.6
(interpolated to
discharge depth)
July: 49.2/20.1
@87'
August: 10.4/7.8
July: 10.3/8.0
June: 6.9/12.2
@37'
August:
20.8/23.5
VP current angle7
(degrees)
90
140
120
225
350
90
7 Zero degrees is eastward.
8 Names of electronic files provided by EPA Region 10 on March 31, 2021.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
In the following sections, the modeling of effluent dilution in mixing zones at each site is presented and
results are displayed in both tables and graphs. Text output from the VP and FARFIELD model
simulations at each location are provided in an appendix to this report.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Haines
The wastewater treated at Haines is discharged 549 m offshore in Portage Cove, Chinook Inlet (Figure 1),
from a 2-port diffuser at a depth of 21.3 m (MLLW9). The permitted maximum flow rate is 2.9 MGD
Other site-specific data for the wastewater discharge, outfall, and ambient receiving water is summarized
in Table 2. The diffuser port spacing at Haines is uncertain (somewhere in the range of 15 to 30 ft.) due to
one of three ports being closed. The models predicted lower DFs for the narrowest port spacing (15 ft.),
so that spacing was used for all model simulations.
>
1 , m ¦ f u
" * 1 " m
*¦ s«w2H<,ar1 * -
urch ~ ~
i '" ' ' hmriei lr'
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
2002, July and August 2004, and June 2005. Preliminary initial dilution simulations made with UM3 for
profiles measured at four of the locations (the fifth was excluded because it was influenced by freshwater
input from a tributary near Skagway), determined that the June 2005 vertical profile from site 1 (shown in
Figure 2) was limiting in terms of minimizing effluent dilution. That profile was used for all subsequent
dilution modeling at Haines.
Figure 2. Vertical Ambient Profile of Temperature, Salinity and Density in Haines Mixing Zones
Resulting in Least Mixing
Mixing zone dilution modeling results for Haines are summarized in Table 3. The two applicable initial
mixing models, UM3 and DKHW, gave nearly identical results for dilution at a distance of 1* depth
(Table 3, simulations 10 vs. 11). UM3 was selected for further analysis at Haines. The initial mixing
model was combined with the Brooks far-field model to extend dilution predictions beyond the initial
mixing region. Dilution factors at distances of l*depth to 10*depth range from 100 to 766 (Table 3,
simulations 15-18); accounting for bacterial decay had a negligible effect on dilution factors. Graphical
examples of the dilution model predictions are presented in Figures 3 (plan view from above of the
discharge plume boundary), 4 (profile view from the side of the discharge plume centerline and boundary)
and 5 (discharge plume average and centerline dilution vs. distance from the outfall). As shown in Table
3, the plume was trapped at a depth of 20 m by the ambient density stratification, the initial mixing region
extended 16 m from the outfall, and the travel time to the mixing zone boundaries ranged from 4 minutes
(MZ=l*depth) to 143 minutes (MZ= 10*depth). A dilution factor of 99 was predicted for the boundary of
the initial mixing region and at the distance to the shore (549 m) the DF was 2770.
The sensitivity of the initial mixing model to a number of inputs (effluent temperature1", current velocity
and direction, and discharge flow rate) is demonstrated in simulations 20-28 (Table 3). Of these
111 The alternative effluent temperature used for sensitivity analysis was the monthly average effluent temperature for
the month found to have the most limited dilution.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
parameters, DFs were most sensitive to variation in effluent flow rate (Q), with dilution increasing with
greater flow. DFs were relatively insensitive to variation in ambient velocity. Sensitivity of the far-field
model to bounding values of the diffusion parameter a (alpha) was also found to have a significant effect
on dilution factors, as was substituting the 4/3-power law with linear eddy diffusivity (see Washington
DoE, 2018 for explanation).
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 3. Haines mixing zone dilution modeling results
Model simulation
Ambient Input
Model(s)
MZ
Distance
(m)
Froude
Number
Dilution
Factor
Dilution
Factor
w/Bacteria
Decay
Trapping
depth (m)
Length of
Initial
Mixing
Region (m)
Travel
Time to
MZ
Boundary
(min)11
1. MZ=1* depth
Skagway site 1
Oct. 2002
UM3
21.3
190
117
118
17
>21.3
2. " "
Skagway site 2
Oct. 2002
UM3
a a
191
118
118
17
>21.3
3. " "
Skagway site 4
Oct. 2002
UM3
a a
190
117
118
17
>21.3
4 " "
Skagway site 1
Jul. 2004
UM3
a a
189
117
118
17
>21.3
5. " "
Skagway site 2
Jul. 2004
UM3/FF
a a
185
110
113
19
20
2
6. " "
Skagway site 4
Jul. 2004
UM3/FF
a a
181
113
116
19
21
0.5
y a a
Skagway site 1
Aug. 2004
UM3
a a
188
118
118
17
>21.3
8. " "
Skagway site 2
Aug. 2004
UM3
a a
186
117
117
17
>21.3
9 " "
Skagway site 4
Aug. 2004
UM3/FF
a a
181
114
117
19
21
0.2
10. " "
Skagway site 1
June 2005
UM3/FF
a a
179
99
104
20
16
5
11. " "
Skagway site 1
June 2005
DKHW/FF
a a
179
99
99
20
16
4
12. " "
Skagway site 2
June 2005
UM3/FF
a a
183
105
109
20
18
2
13. " "
Skagway site 4
June 2005
UM3
a a
185
117
117
17
>21.3
11 Travel time to MZ boundary was calculated only for distances exceeding length of initial mixing region.
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model simulation
Ambient Input
Model(s)
MZ
Distance
(m)
Froude
Number
Dilution
Factor
Dilution
Factor
w/Bacteria
Decay
Trapping
depth (m)
Length of
Initial
Mixing
Region (m)
Travel
Time to
MZ
Boundary
(min)11
Different mixing zone distances:
14. MZ= initial
mixing region
Skagway site 1
June 2005
UM3
16
179
99
100
20
1
15. MZ=1* depth
a a
UM3/FF
21.3
179
100
100
20
16
4
16. MZ=2*depth
a a
UM3/FF
42.6
179
136
137
20
16
19
17. MZ=5* depth
a a
UM3/FF
106.5
179
330
331
20
16
65
18. MZ=10*depth
a a
UM3/FF
213
179
766
768
20
16
143
19. MZ=distance
to nearest shore
a a
UM3/FF
549
179
2770
2780
20
16
386
Model sensitivity:
20.avg.effluent
T=11.975° C
Skagway site 1
June 2005
UM3/FF
21.3
181
100
100
20
16
4
21. lA* current
v=1.15 cm/s
a a
UM3/FF
a a
178
101
101
20
16
8
22. % * current
v=0.575 cm/s
UM3/FF
a a
179
120
120
20
16
16
23. 2*current
v=4.6 cm/s
a a
UM3/FF
a a
179
105
105
20
17
2
24. average
current v=12.6
cm/s
a a
UM3/FF
a a
179
126
126
20
19
4
25. reverse current
direction=270°
a a
UM3/FF
a a
179
92
92
20
15
4
26. average
Q=0.27 MGD
a a
UM3/FF
a a
17
63
63
18
5
12
27. Q/2=1.45
MGD
a a
UM3/FF
a a
89
87
87
20
11
7
28. 2*Q=5.8
MGD
a a
UM3
a a
358
111
111
20
21
0.5
12
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model simulation
Ambient Input
Model(s)
MZ
Distance
(m)
Froude
Number
Dilution
Factor
Dilution
Factor
w/Bacteria
Decay
Trapping
depth (m)
Length of
Initial
Mixing
Region (m)
Travel
Time to
MZ
Boundary
(min)11
Far-field model sensitivity to diffusion parameter:
29. alpha=0.0001
Skagway site 1
June 2005
UM3/FF
213
178
248
249
20
16
143
30.
alpha=0.000453
a a
UM3/FF
a a
178
1280
1280
20
16
143
31. Linear eddy
diffusivity
a a
UM3/FF
a a
178
486
488
20
16
143
13
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Plan View
V
-75 -SO -25 0 25 50 75 100
Vtest-East (m)
Figure 3. Haines Discharge Plume Boundary Plan View from Above
Elevation View
Figure 4. Haines Discharge Plume Centerline and Boundary Profile View from Side
Plumes Effective DMIon Prediction
Distance frtm Soiree (m)
Figure 5. Haines Discharge Plume Average and Centerline Dilution vs. Distance from Outfall
14
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Ketchikan
The wastewater treated at Ketchikan is discharged 221 m offshore of Charcoal Point in the Tongass
Narrows (Figure 6), at a depth of 29.9 m (MLLW). Other site-specific data for the wastewater discharge,
outfall, and ambient receiving water is summarized in Table 2.
Figure 6. Aerial View of the POTW Outfall Location at Ketchikan
Charcoal Point is at the narrowest width of the Narrows and is approximately 400 m wide and 34 m deep.
According to the 2000 Permit application, the Tongass Narrows has a net northwest seaward exchange
(away from the City and Pennock Island) with the Gulf of Alaska. Strong currents (that do not vary
seasonally) provide vertical mixing in Tongass Narrows, minimizing the vertical density gradient and
preventing stratification. Ambient tidal current data were collected with a current meter deployed near
shore in December 1988 to verify published Tidal Current Table predictions. The data collected indicate
that the flood tide current velocity was 34 cm/s, while the ebb tide currents was 1 cm/s in both directions.
NOAA 6-minute tidal current predictions from East of Airport (SEA0711) were used to calculate the 10th
percentile and average tidal current velocities at a depth of 87 ft. (26.5 m; Table 2). The 10th percentile
current velocity used for modeling was 5.9 cm/s, while the average ebb and flood tidal velocities were
49.2 and 20.1 cm/s.
Preliminary initial dilution simulations made with UM3 for five available ambient profiles, determined
that the July 1997 vertical profile from Site 3 (Figure 7) was limiting in terms of minimizing effluent
dilution. As noted previously, the diffuser at Ketchikan was a hybrid, consisting of five 6-inch ports on a
manifold and a single 12-inch port. These were modeled separately, and initial simulations with both
UM3 and DKHW demonstrated that effluent dilution from the single 12-inch port was lower than from
the five, 6-inch ports. UM3 gave more conservative dilution predictions (see Table 4, simulations 5 vs. 6),
so that initial mixing model was selected for further analysis at Ketchikan.
15
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Figure 7. Vertical Ambient Profile of Temperature, Salinity and Density in Ketchikan Mixing Zone
Resulting in Least Mixing.
-Temperature (°C)
-Salinity (g/kg)
-Density (sigma-T)
10 15 20 25
Temperature, Salinity and Density
Site 3 7/15/1997
The initial mixing model was combined with the Brooks far-field model to extend dilution predictions
beyond the initial mixing region. Because the nearest shoreline was within ten times the plume diameter
(calculated as the 10*depth mixing zone distance), it was assumed to impose a boundary constraint on
far-field mixing. Following the guidance of Frick et al. (2010), we based far-field predictions at
Ketchikan on the linear eddy diffusivity (LED) parameterization in FARFIELD. Sensitivity of DF
predictions to this assumption is shown in Table 4 (simulations 20 vs. 31 and 32).
Dilution factors at distances of l*depth to 10*depth range from 52 to 179 (Table 4, simulations 17-20). It
should be noted that the 10*depth distance (299 m) is greater than the distance from the diffuser to shore
(221 m), so it may be appropriate to truncate DF predictions at the distance to shore. Graphical examples
of the dilution model predictions are presented in Figures 8 (plan view from above of the discharge plume
boundary), 9 (profile view from the side of the discharge plume centerline and boundary) and 10
(discharge plume average and centerline dilution vs. distance from the outfall). Note that these figures
include dilution model predictions for both the single 12-inch port and the five 6-inch ports. As shown in
Table 4, the plume was trapped at a depth of 22 m by the ambient density stratification, the initial mixing
region extended 13 m from the outfall. The travel time to the mixing zone boundaries ranged from 5
minutes (MZ=l*depth) to 81 minutes (MZ= 10*depth). A dilution factor of 51 was predicted forthe
boundary of the initial mixing region and at the distance to the shore (221 m) the DF was 141.
16
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
The sensitivity of the initial mixing model to a number of inputs (effluent temperature12, current velocity
and direction, and discharge flow rate) is demonstrated in simulations 22-30 (Table 4). Of these
parameters, DFs were most sensitive to variation in ambient velocity (simulations 23-26).
12 The alternative effluent temperature used for sensitivity analysis was the average of maximum monthly effluent
temperatures (no monthly averages in DMR).
17
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 4. Ketchikan Mixing Zone Dilution Modeling Results
Model
simulation
Ambient
input
Model(s)
MZ
distance
(m)
Diffuser
port(s)
Froude
number
Dilution
factor
Dilution
factor w /
bacteria
decay
Trapping
depth (m)
Length
of initial
mixing
region
(m)
Travel
time to
MZ
boundary
(min)
1. MZ=1* depth
Ketchikan
2000
UM3/FF
29.9
12" port
14
73
75
19
15
4
2. " "
a a
UM3(half
spacing)/FF
a a
5x6" ports
18
117
123
22
12
5
3. " "
Ketchikan
Pier
12/1988
UM3/FF
a a
12" port
14
158
168
7
17
4
4. " "
a a
UM3(half
spacing)/FF
a a
5x6" ports
18
305
324
8
18
3
5. " "
Ketchikan
site 3
7/1997
UM3/FF
a a
12" port;
limiting
14
52
54
22
13
5
6. " "
a a
DKHW/FF
a a
12" port
14
79
79
24
12
5
7. " "
a a
UM3(DS
only, 3 ports
x7.35")/FF
a a
5x6" ports
17
60
62
23
12
5
8. " "
Ketchikan
site 3
9/1997
UM3/FF
a a
12" port
14
99
104
14
15
4
9 cc cc
Ketchikan
site 3
8/1997
UM3/FF
a a
12" port
13
106
112
12
14
4
10. " "
Ketchikan
site 3
7/1996
UM3/FF
a a
12" port
13
99
104
14
15
4
11.""
Ketchikan
site 3
8/1996
UM3/FF
a a
12" port
14
79
83
18
15
4
18
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model
simulation
Ambient
input
Model(s)
MZ
distance
(m)
Diffuser
port(s)
Froude
number
Dilution
factor
Dilution
factor w /
bacteria
decay
Trapping
depth (m)
Length
of initial
mixing
region
(m)
Travel
time to
MZ
boundary
(min)
12. " "
Ketchikan
site 3
9/1996
UM3/FF
a a
12" port
14
101
106
15
16
4
13. " "
Ketchikan
site 3
7/1998
UM3/FF
a a
12" port
14
89
93
16
6
4
14. " "
Ketchikan
site 3
8/1998
UM3/FF
a a
12" port
13
112
118
13
17
4
15. " "
Ketchikan
site 3
9/1998
UM3/FF
a a
12" port
14
92
97
16
16
4
Linear eddy diffusivity (LED) far-field mode
and different mixing zone distances:
16. MZ= initial
mixing region
Ketchikan
3 7/1997
UM3
13
12" port
14
51
52
22
1
17.
MZ=1* depth
Ketchikan
3 7/1997
UM3/FF-LED
29.9
a a
14
52
52
22
13
5
18.
MZ=2* depth
a a
a a
59.8
a a
14
62
63
22
13
13
19.
MZ=5* depth
a a
a a
149.5
a a
14
105
106
22
13
39
20.
MZ=10* depth
a a
a a
29913
a a
14
179
180
22
13
81
21.
MZ=distance to
nearest shore
a a
a a
221
a a
14
141
141
22
13
59
Model sensitivity:
22.avg.effluent
T=14.6° C
Ketchikan
3 7/1997
UM3/FF-LED
29.9
12" port
14
52
52
22
13
5
13 Distance is greater than the distance from the diffuser to shore.
19
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model
simulation
Ambient
input
Model(s)
MZ
distance
(m)
Diffuser
port(s)
Froude
number
Dilution
factor
Dilution
factor w /
bacteria
decay
Trapping
depth (m)
Length
of initial
mixing
region
(m)
Travel
time to
MZ
boundary
(min)
23. lA* current
v=2.95 cm/s
a a
a a
a a
a a
14
54
54
20
13
10
24. % * current
v=1.475 cm/s
a a
a a
a a
a a
14
67
67
20
13
19
25. 2*current
v=11.8 cm/s
a a
a a
a a
a a
14
88
88
24
14
2
26. average
current v=49.2
cm/s
a a
UM3
a a
a a
14
179
180
27
30
1
27. reverse
current
direction=320°
a a
UM3/FF-LED
a a
a a
14
47
47
22
10
6
28. Q/4=0.864
MGD
a a
a a
a a
a a
4
72
72
22
6
7
29. Q/2=1.728
MGD
a a
a a
a a
a a
7
58
59
22
8
6
30. 2*Q=6.912
MGD
a a
a a
a a
a a
28
56
57
23
20
3
Far-field model sensitivity to diffusion parameter:
31.
alpha=0.0001
Ketchikan
3 7/1997
UM3/FF
299
12" port
14
94
94
22
13
81
32.
alpha=0.000453
a a
a a
a a
a a
14
396
398
22
13
81
20
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Plan View
West-East (m)
Figure 8. Ketchikan Discharge Plume Boundary Plan View from Above
(plume from 12-inch port is red; plume from five 6-inch ports is blue)
Elevation View
- Centerline
- Centerline
- Centerline
- Plume Bndry
* Plume Bndry
Plume Bndry
Figure 9. Ketchikan Discharge Plume Centerline and Boundary Profile View from Side
21
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Pfcmes Effective Dilution Prediction
-
/
1 1
/
1
17
77.
CenterUne
Centerline
Centerline
Verification
Distance from Source (m)
Figure 10. Ketchikan discharge plume average and centerline dilution vs. distance from outfall
Figure is based on graphic output by VP; DFs in far field (beyond 13 m for the 12-inch port) are
overestimated because VP assumes 4/3-power law instead of linear eddy diffusivity.
22
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Petersburg
Wastewater treated at Petersburg is discharged 366 m offshore in Frederick Sound (Figure 11), from a
two-port diffusa" at a depth of 18.3 m (MLLW). The permitted maximum flow is 3.6 MGD. Other site-
specific data for the wastewater discharge, outfall, and ambient receiving water is summarized in Table 2.
The port spacing at Petersburg is uncertain (somewhere in the range of 10 to 34 ft.) due to only two of
five diffuser ports being open. The models predicted lower DFs forthe narrowest port spacing (10 ft.), so
that spacing was used for all model simulations.
Figure 11. Aerial View of the POTW Outfall Location at Petersburg
Frederick Sound is connected to the Pacific Ocean via Chatham Strait to the northwest and Dry
Strait/Sumner Strait to the southeast. According to the 1990 permit questionnaire, surface water densities
near the outfall van due to freshwater inputs from nearby streams. Maximum freshwater input to
Frederick Sound occurs in summer (June or July) and minimum freshwater input occurs in March. The
freshwater input is due primarily to the combined flows of the Stikine and Iskut Rivers. Currents
generally flow northwestward in Frederick Sound with southwestward flows during large tides. NOAA
tidal current predictions for nearby Cosmos Point (PCT3811) were used to calculate the 10th percentile
current velocity used for modeling, 1.6 cm/s, and the average ebb and flood tidal velocities, 10.4 and 7.8
cm/s. According to the questionnaire, current velocities in the area are reportedly in the range of two to
five knots (100 to 260 cm/s), 10 to 100 times larger than the velocities calculated from NOAA tidal
current predictions and used for modeling. This discrepancy in the magnitude of ambient velocities could
not be resolved given the information available, but may warrant further inquiry.
Preliminary initial dilution simulations made with UM3 for eight available ambient profiles sampled at
two ZID boundary monitoring locations in January of 2002 and 2004, and August 2003 and 2005,
determined that the August 2005 vertical profile from Site 1 (Figure 12) was limiting in terms of
minimizing effluent dilution.
23
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Figure 12. Vertical Ambient Profile of Temperature, Salinity and Density in Petersburg Mixing
Zone Resulting in Least Mixing
Mixing zone dilution modeling results for Petersburg are summarized in Table 5. The two applicable
initial mixing models, UM3 and DKHW, gave very similar results for dilution at a distance of 1* depth
(67 vs. 70). UM3 gave slightly more conservative dilution predictions, so that initial mixing model was
selected for further analysis at Petersburg. The initial mixing model was combined with the Brooks far-
field model to extend dilution predictions beyond the initial mixing region. Dilution factors at distances of
l*depth to 10*depth range from 67 to 647 (Table 5, simulations 11-14); accounting for bacterial decay
had a negligible effect on dilution factors. Graphical examples of the dilution model predictions are
presented in Figures 13 (plan view from above of the discharge plume boundary), 14 (profile view from
the side of the discharge plume centerline and boundary) and 15 (discharge plume average and centerline
dilution vs. distance from the outfall). As shown in Table 5, the plume was trapped at a depth of 14 m by
the ambient density stratification, the initial mixing region extended 23 m from the outfall, and the travel
time to the mixing zone boundaries ranged from 1 minute (MZ=l*depth) to 167 minutes (MZ= 10*depth).
A dilution factor of 74 was predicted for the boundary of the initial mixing region and at the distance to
the shore (366 m) the DF was 1720.
The sensitivity of the initial mixing model to a number of inputs (effluent temperature, current velocity
and direction, and discharge flow rate) is demonstrated in simulations 16-24 (Table 5). DFs were
moderately sensitive to variation in ambient velocity (DFs increase with velocity, simulations 17-19) and
effluent flow rate (DFs decrease with Q, simulations 21-24). Sensitivity of the far-field model to
bounding values of the diffusion parameter a (alpha) was also found to have a significant effect on
dilution factors, as was substituting the 4/3-power law with linear eddy diffusivity.
24
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 5. Petersburg Mixing Zone Dilution Modeling Results
Model simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth
(m)
Length of
initial
mixing
region (m)
Travel
time to
MZ
boundary
(min)14
1. MZ=1* depth
Petersburg 1
8/2005
UM3
18.3
114
67
67
15
>18.3
2. " "
a a
DKHW
18.3
114
70
70
14
>18.3
3. " "
Petersburg 1
8/2003
UM3
18.3
95
72
73
12
>18.3
4 " "
Petersburg 1
1/2002
UM3
18.3
114
69
69
14
>18.3
5. " "
Petersburg 2
1/2002
UM3
18.3
113
69
69
14
>18.3
6. " "
Petersburg 1
1/2004
UM3
18.3
114
69
69
14
>18.3
y a a
Petersburg 2
1/2004
UM3
18.3
114
69
69
14
>18.3
8. " "
Petersburg 2
8/2003
UM3
18.3
94
72
72
12
>18.3
9 " "
Petersburg 2
8/2005
UM3
18.3
116
68
68
15
>18.3
Dilution at different distances:
10. MZ= initial
mixing region
Petersburg 1
8/2005
UM3
23
115
74
75
14
1
11. MZ=1* depth
a a
UM3
18.3
115
67
67
15
>18.3
1
12. MZ=2*depth
a a
UM3/FF
36.6
115
90
90
14
23
15
13. MZ=5* depth
a a
UM3/FF
91.5
115
256
257
14
23
72
14. MZ=10*depth
a a
UM3/FF
183
115
647
650
14
23
167
15. MZ=distance to
nearest shore
a a
UM3/FF
366
115
1720
1730
14
23
358
14 Travel time to MZ boundary was calculated only for distances exceeding length of initial mixing region.
25
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth
(m)
Length of
initial
mixing
region (m)
Travel
time to
MZ
boundary
(min)14
Model sensitivity:
16.avg.effluent
T=13.2° C
Petersburg 1
8/2005
UM3
18.3
115
67
68
15
>18.3
17. Yi*current v=0.8
cm/s
a a
UM3
18.3
115
66
66
15
>18.3
18. 2*current v=3.2
cm/s
a a
UM3
18.3
115
70
70
15
>18.3
19. average current
v=10.4 cm/s
a a
UM3
18.3
115
80
81
16
>18.3
20. reverse current
direction=300°
a a
UM3
18.3
115
66
66
15
>18.3
21. average Q=0.43
MGD
a a
UM3/FF
18.3
14
81
82
12
6
13
22. 0/4=0.9 MGD
a a
UM3/FF
18.3
29
68
69
13
9
9
23. 0/2=1.8 MGD
a a
UM3/FF
18.3
57
65
65
14
15
4
24. 2*Q=7.2 MGD
a a
UM3
18.3
229
65
65
17
>18.3
Far-field model sensitivity to diffusion parameter:
25. alpha=0.0001
Petersburg 1
8/2005
UM3/FF
183
114
202
203
14
23
167
26. alpha=0.000453
a a
UM3/FF
183
114
1090
1091
14
23
167
27. Linear eddy
diffusivity
a a
UM3/FF
183
114
397
399
14
23
167
26
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
West-East (tn)
Figure 13. Petersburg Discharge Plume Boundary Plan View from Above
Elevation View
Centerline
Centerline
Centerline
Plume Bndry
« Plume Bndry
Plume Bndry
Verification
Figure 14. Petersburg Discharge Plume Centerline and Boundary Profile View from Side
Plumes Effective Dilution Preddion
Distance from Source (m)
Figure 15. Petersburg Discharge Plume Average and Centerline Dilution vs. Distance from Outfall
27
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Sitka
The wastewater treated at Sitka is discharged 114 m offshore in the Middle Channel of Sitka Sound
(Figure 16), from a 16-port diffliser at a depth of 24.4 m (MLLW). The permitted maximum flow is 5.3
MGD.
Figure 16. Aerial View of the POTW Outfall Location at Sitka
According to the permit fact sheet, the Middle Channel has relatively weak tidal currents, rotating in a
clockwise pattern, which are superimposed on the seaward flow of fresh water in Sitka Sound. The net
current is toward the southeast and included an easterly wind-driven component. The direction of
transport of effluent from the outfall varies, depending upon the tidal stage and direction of prevailing
winds. NOAA tidal current predictions for Sitka Harbor, Channel off Harbor Island (PCT4166) were used
to calculate the 10th percentile current velocity used for modeling, 1.7 cm/s, and the average ebb and flood
tidal velocities, 10.3 and 8.0 cm/s.
Other site-specific data for the wastewater discharge, outfall, and ambient receiving water is summarized
in Table 2. Detailed vertical ambient profiles were only available for one location (Site C, a reference
station west of the outfall) that was in sampled in the months of April and July in 2010 and 2015.
Preliminary initial dilution simulations made with UM3 for these four available ambient profiles,
determined that the July 2010 vertical profile from Site C (Figure 17) was limiting in terms of minimizing
effluent dilution (Table 6, simulations 1, 2, 8 and 9).
28
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Figure 17. Vertical Ambient Profile of Temperature, Salinity and Density in Sitka Mixing Zone
Resulting in Least Mixing
Mixing zone dilution modeling results for Sitka are summarized in Table 6. The two initial mixing
models, DKHW and UM3, combined with the Brooks far-field model gave similar results for dilution at a
distance of l*depth (sims. 2 and 5); simulation results for the downstream-only cross-diffuser merging
approach and the third initial mixing model, NRFIELD, also fell within this range of DFs. DKHW gave
slightly more conservative dilution predictions, so that initial mixing model was selected for further
analysis at Sitka.
The initial mixing model was combined with the Brooks far-field model to extend dilution predictions
beyond the initial mixing region. Because the nearest shoreline was within ten times the plume diameter
(calculated as the 10*depth mixing zone distance), it was assumed to impose a boundary constraint on
far-field mixing. Following the guidance of Frick et al. (2010), we based far-field predictions at Sitka on
the linear eddy diffusivity (LED) parameterization in FARFIELD. Sensitivity of DF predictions to this
assumption is shown in Table 6 (simulations 14 vs. 25 and 26).
Dilution factors at distances of l*depth to 10*depth range from 87 to 227 (Table 6, simulations 11-14);
accounting for bacterial decay had a negligible effect on dilution factors. It should be noted that the
5*depth and 10*depth distances (122 and 244 m) are greater than the distance from the diffuser to shore
(114 m), so it may be appropriate to truncate DF predictions at the distance to shore. Graphical examples
of the dilution model predictions are presented in Figures 18 (plan view from above of the discharge
plume boundary), 19 (profile view from the side of the discharge plume centerline and boundary) and 20
(discharge plume average and centerline dilution vs. distance from the outfall). As shown in Table 6, the
plume was trapped at a depth of 10 m by the ambient density stratification, the initial mixing region
extended 6.9 m from the outfall, and the travel time to the mixing zone boundaries ranged from 17
minutes (MZ=l*depth) to 232 minutes (MZ= 10*depth). A dilution factor of 86 was predicted for the
boundary of the initial mixing region and at the distance to the shore (114 m) the DF was 138.
29
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
The sensitivity of the initial mixing model to a number of inputs (effluent temperature, current velocity
and direction, and discharge flow rate) is demonstrated in simulations 16-24 (Table 6). DFs were
moderately sensitive to variation in ambient velocity (DFs increase with velocity, simulations 17-19) and
effluent flow rate (DFs decrease with Q, simulations 22-24).
30
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 6. Sitka Mixing Zone Dilution Modeling Results
Model simulation
Ambient
input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w /
bacteria
decay
Trapping
depth
(m)
Length of
initial
mixing
region (m)
Travel time
to MZ
boundary
(min)15
1. MZ=1* depth
Sitka C
7/2015
UM3(half
spacing)/FF
24.4
11
131
133
9
7
17
2. " "
Sitka C
7/2010
55 a
24.4
12
118
119
12
6
18
3. " "
Sitka C
7/2010
55 a
16.0
12
113
114
12
6
10
4 " "
Sitka C
7/2010
NRFIELD
16.0
12
89
10
5. " "
Sitka C
7/2010
DKHW(half
spacing)/FF
24.4
12
87
87
10
7
17
6. " "
a a,
5
UM3(DS-only, 8
portsx5.3")/FF
24.4
11
109
110
11
7
17
y a a
a a
DKHW(D S -only, 8
portsx5.3")/FF
24.4
11
90
90
10
8
16
8. " "
Sitka C
4/2010
UM3(half-
spacing)/FF
24.4
12
179
181
4
7
17
9 " "
Sitka C
4/2015
55 a
24.4
11
172
174
5
7
17
Linear eddy diffusivity (LED) far-field model and different mixing zone distances:
10. MZ= initial
mixing region
Sitka C
7/2010
DKHW(half-
spacing)
6.9
12
86
86
1
11. MZ=1* depth
a a
DKHW(half-
spacing)/FF-LED
24.4
12
87
87
10
7
17
12. MZ=2*depth
a a
a a
48.8
12
97
97
10
7
41
13. MZ=5* depth
a a
a a
12216
12
143
143
10
7
113
14. MZ=10*depth
a a
a a
24416
12
227
227
10
7
232
15 Travel time to MZ boundary was calculated only for distances exceeding length of initial mixing region.
16 Distance is greater than the distance from the diffuser to shore.
31
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model simulation
Ambient
input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w /
bacteria
decay
Trapping
depth
(m)
Length of
initial
mixing
region (m)
Travel time
to MZ
boundary
(min)15
15. MZ=distance to
nearest shore
a a
a a
114
12
138
138
10
7
105
Model sensitivity:
16.avg.effluent
T=14° C
Sitka C
7/2010
DKHW(half-
spacing)/FF-LED
24.4
12
87
87
10
7
17
17. V2*current
v=0.85 cm/s
a a
a a
a a
12
79
79
9
7
35
18. 2*current v=3.4
cm/s
a a
a a
a a
12
119
119
11
9
8
19. average current
v=10.3cm/s
a a
a a
a a
12
187
187
15
22
0.5
20. reverse current
direction=45°
a a
a a
a a
12
87
87
10
7
17
21. current dir +30°
a a
a a
a a
12
131
131
12
7
17
22. average Q=0.98
MGD
a a
a a
a a
2
208
208
15
4
20
23. Q/2=2.65 MGD
a a
a a
a a
6
121
121
12
5
19
24. 2*Q=10.6 MGD
a a
a a
a a
23
66
66
8
12
12
Far-field model sensitivity to diffusion parameter:
25. alpha=0.0001
Sitka C
7/2010
DKHW(half-
spacing)/FF
244
12
126
126
10
7
233
26. alpha=0.000453
a a
a a
a a
12
426
426
10
7
233
32
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
-40 -30 -20 -10 0 10
West-East (m)
Figure 18. Sitka Discharge Plume Boundary Plan View from Above
Centerline
Centerline
Centerline
Outline
Outline
Outline
Verification
Elevation View
Distance trom Otiain fmi
Figure 19. Sitka Discharge Plume Centerline and Boundary Profile View from Side
33
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Plumes Effective Dilution Prediction
\ y
s
s
1
Distance from Source (m)
Average
Average
Average
* Centerline
» Centerline
* Centerline
Verification
Figure 20. Sitka Discharge Plume Average and Centerline Dilution vs. Distance from Outfall
(Figure is based on graphic output by VP; DFs in far field (beyond 7 m) are overestimated because VP
assumes 4/3-power law instead of linear eddy diffusivity).
34
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Skagway
Wastewater treated at Skagway is discharged 125 m offshore in Tiaya Inlet (Figure 21), at a depth of 18.3
ill (MLLW), from an 8-port diffuser. The permitted maximum flow rate is 0.63 MGD.
Figure 21. Aerial View of the POTW Outfall Location at Skagway
According to the permit fact sheet, Taiya Inlet is a deep fjord with a 457 m average depth. Taiya Inlet
supports a classic fjord-type, two-layer circulation, with a large saline lower layer and a very thin upper
brackish layer. The circulation of the inlet is dependent on tides and freshwater flow into the inlet. There
are no obstructions to impede circulation near the outfall. Stratification in Taiya Inlet is dependent on
freshwater inflows from the Taiya and Skagway Rivers with the highest stratification typically occurs
during the high runoff summer period from June through August. As noted in the 2007 permit
reapplication, a small cross-current (2 cm/s) was present under stratified condition in a June 1999
temperature/salinity data set.
NO A A 6-minute tidal current predictions from Tiaya Inlet (SEA0825) were used to calculate the 10th
percentile and average tidal current velocities (Table 2). The 10th percentile current velocity used for
modeling was 1.4 cm/s, while the average ebb and flood tidal velocities were 6.9 and 12.2 crn/s.
Other site-specific data for the wastewater discharge, outfall, and ambient receiving water is summarized
in Table 2. Vertical profiles of temperature and salinity measured in Tiaya Inlet were available for five
locations that were sampled in October 2002, July and August 2004 and June 2005. Preliminary initial
dilution simulations made with UM3 for all available profiles, determined that the June 2005 vertical
profile measured at site 1 (shown in Figure 22) was limiting in terms of minimizing effluent dilution17.
That profile was used for all subsequent dilution modeling at Skagway.
17 A different vertical profile measured in June 2005 at site 5 (a site in the cmise ship terminal harbor nearest to
freshwater inflow from the Skagway River) actually produced smaller DF predictions. However, the unusually low
35
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Figure 22. Vertical Ambient Profile of Temperature, Salinity and Density in Skagway Mixing Zone
Resulting in Least Mixing
Mixing zone dilution modeling results for Skagway are summarized in Table 7. Two of the applicable
initial mixing models, UM3 and DKHW, gave similar results for dilution at a distance of l*depth, for
both cross-diffuser merging approaches (simulations 11-13). UM3 gave slightly more conservative
dilution predictions, so that initial mixing model was selected for further analysis at Skagway. We also
applied the third initial mixing model, NRFIELD, that predicted DFs reasonably comparable to UM3
(simulations 14 vs. 15) at a distance shorter than l*depth (5.9 m).
The initial mixing model was combined with the Brooks far-field model to extend dilution predictions
beyond the initial mixing region. Because the nearest shoreline was within ten times the plume diameter
(calculated as the 10*depth mixing zone distance), it was assumed to impose a boundary constraint on
far-field mixing. Following the guidance of Frick et al. (2010), we based far-field predictions at Skagway
on the linear eddy diffusivity (LED) parameterization in FARFIELD. Sensitivity of DF predictions to this
assumption is shown in Table 7 (simulations 23 vs. 33 and 34).
Dilution factors at distances of l*depth to 10*depth range from 56 to 330 (Table 7, simulations 20-23);
accounting for bacterial decay had a negligible effect on dilution factors. It should be noted that the
10*depth distance (183 m) is greater than the distance from the diffuser to shore (125 m), so it may be
appropriate to truncate DF predictions at the distance to shore. Graphical examples of the dilution model
predictions are presented in Figures 23 (plan view from above of the discharge plume boundary), 24
salinity of the upper 3-4 m of that profile led to difficulties in modeling dilution over the range of parameters and
conditions of interest, so the site 1 June 2005 profile (that was the next most conservative in terms of limiting DFs)
was used instead.
36
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
(profile view from the side of the discharge plume centerline and boundary) and 25 (discharge plume
average and centerline dilution vs. distance from the outfall). As shown in Table 7, the plume was trapped
at a depth of 15 m by the ambient density stratification, the initial mixing region extended 3.5 m from the
outfall, and the travel time to the mixing zone boundaries ranged from 18 minutes (MZ=l*depth) to 214
minutes (MZ= 10* depth). A dilution factor of 42 was predicted for the boundary of the initial mixing
region and at the distance to the shore (125 m) the DF was 233.
The sensitivity of the initial mixing model to a number of inputs (effluent temperature, current velocity
and direction, and discharge flow rate) is demonstrated in simulations 25-32 (Table 7). DFs were
moderately sensitive to variation in ambient velocity (minimum DFs at velocities near 2 cm/s, simulations
26-28) and effluent flow rate (DFs decrease with Q, simulations 30-32).
37
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 7. Skagway Mixing Zone Dilution Modeling Results
Model
simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth (m)
Length
of
initial
mixing
region
(m)
Travel
time to
MZ
boundary
(min)
1. MZ=1* depth
Skagway site 1 10/02
UM3 (half
spacing) /FF
18.3
10
129
130
9
4
17
2. " "
Skagway site 2 10/02
55 a
18.3
10
145
147
7
5
16
3. " "
Skagway site 4 10/02
55 a
18.3
10
127
128
9
4
17
4 " "
Skagway site 1 7/2004
55 a
18.3
10
94
95
12
4
18
5. " "
Skagway site 2 7/2004
55 a
18.3
10
97
97
12
4
17
6. " "
Skagway site 4 7/2004
55 a
18.3
10
79
79
13
4
17
y a a
Skagway site 1 8/2004
55 a
18.3
10
130
131
9
4
17
8. " "
Skagway site 2 8/2004
55 a
18.3
10
113
114
10
4
17
9 " "
Skagway site 4 8/2004
55 a
18.3
10
82
83
13
4
17
10. " "
Skagway site 1 6/2005
55 a
18.3
10
59
59
15
3
18
11. " "
a a
UM3(DS-
only,
4x3.95")/FF
18.3
10
59
59
14
5
16
12. " "
a a
DKHW(half
spacing)/FF
18.3
10
62
63
16
3
18
13. " "
a a
DKHW(DS-
only,
4x3.95")/FF
18.3
10
66
66
15
4
17
14. " "
a a
NRFIELD
5.9
10
39
14
15. " "
a a
UM3(half
spacing) /FF
5.9
10
42
42
15
3
3
16. " "
Skagway site 2 6/2005
55 a
18.3
10
80
80
13
4
17
17. " "
Skagway site 4 6/2005
55 a
18.3
10
100
100
12
4
17
18. " "
Skagway site 5 6/2005
55 a
18.3
9
39
39
16
2
19
Linear eddy diffusivity (LED) far-field model and different mixing zone distances:
19. MZ= initial
mixing region
Skagway site 1 6/2005
UM3(half
spacing)
3.5
10
42
42
15
0.7
38
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model
simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth (m)
Length
of
initial
mixing
region
(m)
Travel
time to
MZ
boundary
(min)
20. MZ=1* depth
a a
UM3(half
spacing) /FF-
LED
18.3
10
56
56
15
3
18
21. MZ=2* depth
a a
a a
36.6
10
86
86
15
3
39
22. MZ=5* depth
a a
a a
91.5
10
177
178
15
3
105
23.
MZ=10* depth
a a
a a
18318
10
330
331
15
3
214
24. MZ=distance
to nearest shore
a a
a a
125
10
233
234
15
3
145
Model sensitivity:
25.avg.effluent
T=14.7° C
Skagway site 1 6/2005
UM3(half
spacing) /FF-
LED
18.3
10
56
56
15
3
18
26. lA* current
v=0.7 cm/s
a a
a a
a a
10
76
76
15
3
36
27. 2*current
v=2.8 cm/s
a a
a a
a a
10
52
52
15
4
9
28. average
current v=12.2
cm/s
a a
a a
a a
10
101
101
17
6
2
29. reverse
current
direction=170°
a a
a a
a a
10
56
56
14
5
19
30. average
Q=0.27 MGD
4
73
73
15
2
19
31. Q=0.5 MGD
a a
a a
a a
8
60
60
15
3
18
18 Distance is greater than the distance from the diffuser to shore.
39
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model
simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth (m)
Length
of
initial
mixing
region
(m)
Travel
time to
MZ
boundary
(min)
32. 2*Q=1.26
MGD
a a
a a
a a
20
49
49
15
5
16
Far-field model sensitivity to diffusion parameter:
33. alpha=0.0001
Skagway site 1 6/2005
UM3(half
spacing) /FF
183
10
173
174
15
3
214
34.
alpha=0.000453
a a
a a
183
10
1100
1103
15
3
214
40
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Figure 23. Skagway Discharge Plume Boundary Plan View from Above
- Centerline
- CenterNne
- Centerline
Plume Bndry
- Plume Bndry
Plume Bndry
- Verification
Distance from Origin (m)
Figure 24. Skagway Discharge Plume Centerline and Boundary Profile View from Side
Plumes Effective Dilution Predctlon
: y\
: /
:
/ :
; /
₯
/
/
/.
Distance from Source (m)
175 20
Figure 25. Skagway Discharge Plume Average and Centerline Dilution vs. Distance from Outfall
(Figure is based on graphic output by VP; DFs in far field (beyond 3 m) are overestimated because VP
assumes 4/3-power law instead of linear eddy diffxisivity)
41
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Wrangell
The wastewater treated at Wrangell is discharged 457 m offshore in the Zimovia Strait (Figure 26), at a
depth of 30.5 m (MLLW), from a 16-port diffuser. The permitted maximum flow rate is 3.0 MGD.
Figure 26. Aerial View of the POTW Outfall Location at Wrangell
According to the permit fact sheet, Zimovia Strait has a net northwest seaward exchange with the Gulf of
Alaska. The maximum current velocity is around 51.4 cm/sec (1.0 knot) and the water circulation patterns
do not vary seasonally. Strong currents provide vertical mixing, minimize the vertical density gradient,
and prevent stratification. Also, according to the permit fact sheet, prior dilution modeling in Zimovia
Strait used a conservative current speed of 2.35 cm/sec and no stratification. NOAA tidal current
predictions for Wrangell Harbor (PCT3131) were used to calculate the 10th percentile current velocity
used for modeling, 4.0 cm/s, and the average ebb and flood tidal velocities, 20.8 and 23.5 cm/s.
Other site-specific data for the wastewater discharge, outfall, and ambient receiving water is summarized
in Table 2. Vertical profiles of temperature and salinity measured in Zimovia strait at the ZID boundaries
were available for two mixing zone locations that were sampled in August of 2015, 2016 and 2017.
Preliminary initial dilution simulations made with UM3 for all profiles, determined that the vertical
profile measured at station 4 in August of 2016 (shown in Figure 27) was limiting in terms of minimizing
effluent dilution. That profile was used for all subsequent dilution modeling at Wrangell.
42
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Station 4 8/17/2016
0
5
10
?
£ 15
Q.
OJ
D
$ 20
4->
i
25
30
35
0 2 4 6 8 10 12 14 16 18
Temperature, Salinity and Density
Figure 27. Vertical Ambient Profile of Temperature, Salinity and Density in Wrangell Mixing Zone
Resulting in Least Mixing
Mixing zone dilution modeling results for Wrangell are summarized in Table 8. Two of the applicable
initial mixing models, UM and DKHW, gave different results for dilution at a distance of l*depth (30.5
m; simulations 3 vs. 4). The third initial mixing model, NRFIELD, predicted a lower DF at a distance
shorterthan l*depth (16.8 m; simulations 5 vs. 6). UM3 gave more conservative DF results (simulation
7) when run using the downstream-only cross-diffuser merging, so we selected this approach for further
analysis at Wrangell. The initial mixing model was combined with the Brooks far-field model to extend
dilution predictions beyond the initial mixing region. Sensitivity of the far-field model to bounding values
of the diffusion parameter a was found to have a significant effect on dilution factors, as was substituting
the 4/3-power law with linear eddy diffusivity.
Dilution factors at distances of l*depth to 10*depth range from 112 to 229 (Table 8, simulations 10-13);
accounting for bacterial decay had a negligible effect on dilution factors. Graphical examples of the
dilution model predictions are presented in Figures 28 (plan view from above of the discharge plume
boundary), 29 (profile view from the side of the discharge plume centerline and boundary) and 30
(discharge plume average and centerline dilution vs. distance from the outfall). As shown in Table 8, the
plume was trapped at a depth of 24 m by the ambient density stratification, the initial mixing region
extended 12 m from the outfall, and the travel time to the mixing zone boundaries ranged from 8 minutes
(MZ=l*depth) to 122 minutes (MZ=10*depth). A dilution factor of 112 was predicted for the boundary
of the initial mixing region and at the distance to the shore (457 m) the DF was 323.
The initial mixing model was moderately sensitive to a number of inputs (effluent temperature, current
velocity and direction, and discharge flow rate) is demonstrated in simulations 16-24 (Table 8). DFs were
sensitive to variation in ambient velocity (dilution increasing with velocity, simulations 17-19) and
effluent flow rate (dilution decreases with Q, simulations 21-24).
43
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Table 8. Wrangell Mixing Zone Dilution Modeling Results
Model simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth
(m)
Length of
initial
mixing
region (m)
Travel
time to
MZ
boundary
(min)19
1. MZ=1* depth
Wrangell station
4 8/2015
UM3(half
spacing)/FF
30.5
34
262
274
23
15
7
2. " "
Wrangell station
3 8/2016
a a
a a
33
232
243
23
13
8
3. " "
Wrangell station
4 8/2016
a a
a a
32
153
160
25
10
8
4 " "
a a
DKHW(half
spacing)/FF
a a
32
228
228
26
11
8
5. " "
a a
UM3 (half
spacing)/FF
16.8
32
153
157
25
10
3
6. " "
a a
NRFIELD
16.8
33
75
25
y a a
a a
UM3(DS-only,
8x3.95")/FF
30.5
33
112
117
24
12
8
8. " "
Wrangell station
3 8/2017
UM3(half-
spacing)/FF
a a
39
494
516
17
25
2
9 " "
Wrangell station
4 8/2017
a a
a a
40
743
791
6
21
4
Dilution at different distances:
10. MZ= initial
mixing region
Wrangell station
4 8/2016
UM3 (DS-
only, 8x3.95")
12
33
112
113
24
2
11. MZ=1* depth
a a
UM3(DS-only,
8x3.95")/FF
30.5
33
112
113
24
12
8
12. MZ=2*depth
a a
a a
61
33
115
115
24
12
20
13. MZ=5* depth
a a
a a
152.5
33
149
149
24
12
59
14. MZ=10*depth
a a
a a
305
33
229
230
24
12
122
19 Travel time to MZ boundary was calculated only for distances exceeding length of initial mixing region.
44
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Model simulation
Ambient input
Model(s)
MZ
distance
(m)
Froude
number
Dilution
factor
Dilution
factor w/
bacteria
decay
Trapping
depth
(m)
Length of
initial
mixing
region (m)
Travel
time to
MZ
boundary
(min)19
15. MZ=distance
to nearest shore
a a
a a
457
33
323
325
24
12
185
Model sensitivity:
16. avg. effluent
T=17.3° C
Wrangell station
4 8/2016
UM3(DS-only,
8x3.95")/FF
30.5
33
112
112
24
12
8
17. lA*current v=2
cm/s
a a
a a
a a
33
86
86
24
11
16
18. 2*current v=8
cm/s
a a
a a
a a
33
198
199
25
15
3
19. ave. current
v=23.5 cm/s
a a
UM3 (DS-
only, 8x3.95")
a a
33
412
412
27
31
2
20. reverse current
direction=270°
a a
UM3(DS-only,
8x3.95")/FF
a a
33
112
113
24
12
8
21. ave. Q=0.36
MGD
a a
a a
a a
3.9
243
244
26
5
11
22. Q/4=0.75
MGD
a a
a a
a a
8.1
161
161
25
6
10
23. Q/2=l .5 MGD
a a
a a
a a
16
125
126
25
8
9
24. 2*Q=6.0 MGD
a a
a a
a a
65
119
120
25
18
5
Far-field model sensitivity to diffusion parameter:
25. alpha=0.0001
Wrangell station
4 8/2016
UM3(DS-only,
8x3.95")/FF
305
33
130
131
24
12
122
26.
alpha=0.000453
a a
a a
a a
33
321
323
24
12
122
27. Linear eddy
diffusivity
a a
a a
a a
33
203
204
24
12
122
45
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
WKt-EosUm)
Figure 28. Wrangell Discharge Plume Boundary Plan View from Above
Elevation View
- Centerline
Plume Bndry
Plume Bndry
Figure 29. Wrangell Discharge Plume Centerline and Boundary Profile View from Side
Piixnes Effective Diution Prediction
¦ Cer*etfne
- Verification
Distance from Source (m)
Figure 30. Wrangell Discharge Plume Average and Centerline Dilution vs. Distance from Outfall
46
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Summary
A summary of the average dilution predictions at various distances (corresponding to 1-10 times the depth
of discharge) from the discharge point at each Alaskan mixing zone location is presented in Table 9. As
indicated in this table, some of the distances exceed the distance from the outfall to the nearest shore.
Under some conditions the tidal currents could direct the discharge plume towards the shore and, upon
reaching this boundary, further mixing would likely not occur. The distance from the outfall to nearest
shore at each location and the predicted DFs and travel times for these distances are presented in Table
10. The dilution predictions are also graphed as a function of distance from the outfall (Figure 31). In this
figure, DFs for Ketchikan, Sitka and Skagway have been truncated at the distance to shore.
Table 9. Average Dilution Factor Predictions at Distances from the Discharge Point Corresponding
to 1-10 Times the Depth of Discharge
Location
1 * depth
2* depth
5*depth
10*depth
Distance
(m)
DF
Time
(min)
Distance
(m)
DF
Time
(min)
Distance
(m)
DF
Time
(min)
Distance
(m)
DF
Time
(min)
Haines
21.3
100
4
43
136
19
107
330
65
213
766
143
Ketchikan
29.9
52
5
60
62
13
150
105
39
299*
179
81
Petersburg
18.3
67
1
37
90
15
92
256
72
183
647
167
Sitka
24.4
87
17
49
97
41
122*
143
113
244*
227
232
Skagway
18.3
56
18
37
86
39
92
177
105
183*
330
214
Wrangell
30.5
112
8
61
115
20
153
149
59
305
229
122
* Distance greater than the distance from the outfall to shore.
Table 10. Average Dilution Factor Predictions at the Distance from the Outfall to Shore
Distance from
DF at distance from
Travel time to
Location
outfall to shore (m)
outfall to shore
shore (min)
Haines
549
2770
386
Ketchikan
221
141
59
Petersburg
366
1720
358
Sitka
114
138
105
Skagway
125
233
145
Wrangell
457
323
185
47
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
900
~Haines
-«~ Ketchikan
« Petersburg
0
0 SO 100 ISO 200 ?S0 300 350
Distance (m)
Figure 31. DF Predictions Graphed as a Function of Distance from the Outfall
(predictions are DFs for distances corresponding to 1-10 times the depth of discharge; in the cases of
Ketchikan, Sitka and Skagway, DFs have been truncated at the distances to the shore)
A summary of the dilution factors predicted at the initial mixing region boundaries is presented in Table
11. For each location this table includes the distance to this boundary, the predicted DF and the travel
times to the boundary. Compared to the depth-based distances in Table 9, the initial mixing region
boundary distances are quite short, although the DFs at a distance of 1* depth are comparable (within
25%) of the initial mixing region dilution factors.
Table 11. Dilution Factor Predictions at Distances Equal to Initial Mixing Region Boundaries
Location
Initial Mixing
Region
Boundary (m)
DF
Travel Time
to Boundary
(min)
Haines
16
99
1
Ketchikan
13
51
1
Petersburg
23
74
1
Sitka
6.9
86
1
Skagway
3.5
42
0.7
Wrangell
12
112
2
48
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
The far-field model was also used to calculate the distances required to attain the FC criteria (i.e., the DFs
in Table 1). These distances, presented in Table 11, range from 3.4 to 135 km to attain the 43/100 mL FC
criterion and 7.2 to 420 km to attain the 14/100 mL FC criterion. These distances greatly exceed the
mixing zone sizes certified by the state in the current wastewater discharge permits for the six POTW
facilities.
Table 12. Dilution Factors and Mixing Zone Distances Required to Attain FC Criteria
DF required to
Distance to attain
DF required to
Distance to attain
Location
attain the 43/100
the 43/100 mL
attain the 14/100
the 14/100 mL FC
mL FC criterion
FC criterion (km)
mL FC criterion
criterion (km)
Haines
50,000
4.0
150,000
8.3
Ketchikan
67,000
135
210,000
420
Petersburg
47,000
3.4
140,000
7.2
Sitka
87,000
126
270,000
390
Skagway
60,000
36
190,000
114
Wrangell
4,400
3.9
14,000
8.9
49
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
References
Dissing, D. and G. Wendler. 1998. Solar Radiation Climatology of Alaska. Theor. Appl. Climatol. 61, pp.
161-175.
Environmental Protection Agency (EPA). 1991. Technical Support Document for Water Quality-based
Toxics Control. United States Environmental Protection Agency, Office of Water. Washington, D.C.
March 1991. EPA/505/2-90-001.
Environmental Protection Agency (EPA). 1994. Dilution Models for Effluent Discharges, 3rd Edition.
United States Environmental Protection Agency, Office of Research and Development. Washington, DC.
June 1994. EPA/600/R-94/086.
Environmental Protection Agency (EPA). 2003. Dilution Models for Effluent Discharges, 4th Edition
(Visual Plumes). United States Environmental Protection Agency, National Exposure Research
Laboratory. Research Triangle Park, NC. March 2003. EPA/600/R-03/025.
Frick, W., Ahmed, A., George, K. and P. Roberts. 2010. On Visual Plumes and associated applications.
Presented at the 6th International Conference on Marine Waste Water Discharges and Coastal
Environment. Langkawi, Malaysia. October 2010.
Frick, W. and P.J.W. Roberts. 2019. Visual Plumes (Plumes20.exe) October 2019 Update, the UM3
plume-water surface reflection approximation and mixing zone endpoints
(https://ftp.waterboards.ca.gov/Surface%20reflection%20tech.docx).
MixZone Inc. 2020. CorHyd Internal Diffuser Hydraulics Model User Manual. December 15, 2020.
Reese, C., George, K. and Gerry Brown. 2021. Mixing zones 101 (PowerPoint presentation). Alaska
Department of Environmental Conservation (https://dec.alaska.gov/media/16267/mixing-zones.pdf.
accessed April 21, 2021).
Washington Department of Ecology (DoE). 2018. Permit Writer's Manual (Revised January 2015/
Updated September 2018). Publication no. 92-109 Part 1. Appendix C. Water Quality Program,
Washington State Department of Ecology. Olympia, Washington
(https://fortress.wa.gov/ecy/publications/SummaryPages/92109partl.html).
50
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
Appendix: VP and FARFIELD20 Output for Each Location
Haines (model output for l*depth, 2*depth, 5*depth and 10*depth)
Contents of the memo box (may not be current and must be updated manually)
Project "C:\Plumes20\Haines" memo4
Model configuration items checked: Brooks far-field solution;
Channel width (m) 100
Start case for graphs 1
Max detailed graphs 10 (limits plots that can overflow memory)
Elevation Projection Plane (deg) 0
Shore vector (m,deg) not checked
Bacteria model : Mancini (1978) coliform model
PDS sfc. model heat transfer : Medium
Equation of State : S, T
Similarity Profile : Default profile (k=2.0, ...)
Diffuser port contraction coefficient 0.61
Light absorption coefficient 0.16
Farfield increment (m) 200
UM3 aspiration coefficient 0.1
Output file: text output tab
Output each ?? steps 100
Maximum dilution reported 100000
Text output format: Standard
Max vertical reversals : to max rise or fall
/ UM3. 6/23/2021 5:19:37 AM
Case 1; ambient file C:\Plumes20\Haines_Skagway_l_Jun05.006.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.023 90.00 7.100
I.523 0.023 90.00 14.16
3.047 0.023 90.00 23.30
4.570 0.023 90.00 23.25
6.090 0.023 90.00 25.20
7.617 0.023 90.00 26.37
9.140 0.023 90.00 26.74
10.45 0.023 90.00 27.46
II.75 0.023 90.00 28.24
13.06 0.023 90.00 28.92
14.37 0.023 90.00 29.08
15.68 0.023 90.00 29.29
16.98 0.023 90.00 30.42
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s
11.12 0.0 0.000192
10.08 0.0 0.000194
8.650 0.0 0.000193
8.670 0.0 0.000193
8.220 0.0 0.000193
8.020 0.0 0.000193
7.980 0.0 0.000193
7.570 0.0 0.000193
7.100 0.0 0.000193
6.920 0.0 0.000193
6.880 0.0 0.000192
6.790 0.0 0.000192
6.260
0.0
0.0
0.0 0.000192
deg
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
m0.67/s2 sigma-
90.00 0.0003 5
0.0003
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
If required.
51
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
22.00 0.023 90.00 34.78 4.213 0.0 0.000192 0.023 90.00 0.0003 27.61629
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.0000 0.0 90.000 0.0 0.0 2.0000 15.000 21.300 200.00 21.100 2.9000 0.0 15.800
2.13E+6
Simulation:
Froude No: 178.8; StratNo: 2.20E-3; Spcg No: 76.82; k: 992.9; eff den (sigmaT) -0.960860; eff vel
22.84(m/s);
Depth Amb-cur P-dia Polutnt Dilutn x-posn y-posn Iso dia
Step
(m)
(cm/s)
(in) (col/dl) ()
(m)
(m)
(m)
0
21.10
2.300
2.343 2.130E+6
1.000
0.0
0.0
0.0; 10.68 T-90hr,
100
21.10
2.300
23.86 208749.0
10.20
0.000
1.346
0.6058; 10.68 T-90hr,
160
21.03
2.300
77.28 63725.7
33.42
0.000
4.775
1.9614; bottom hit; 10.65 T-90hr,
200
20.49
2.300
166.7 28847.1
73.76
0.000
10.62
4.2261; 10.42 T-90hr,
204
20.37
2.300
179.9 26645.8
79.84
0.000
11.48
4.5599; trap level; 10.37 T-90hr,
205
20.34
2.300
183.3 26122.1
81.44
0.000
11.71
4.6475; merging; 10.36 T-90hr,
232
19.97
2.300
305.7 21392.8
99.34
0.000
16.27
7.7425; local maximum rise or fall;
10.20
T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.0; CL(m): 16.274
Lmz(m): 16.274
forced entrain 1 1.873 1.132 7.764 1.000
Rate sec-1 0.00019515 dy-1 16.8607 kt: 0.000062421 Amb Sal 33.0175
Const Eddy Diffusivity. Farfield dispersion based on wastefield width of 12.34 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
21392.8 99.34 12.34 16.27 2.78E-4 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
20539.8 99.48 14.21 21.30 0.061 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
18354.2 113.1 20.80 37.57 0.258 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
count: 1
5:19:40 AM. amb fills: 4
/ UM3. 6/23/2021 5:20:06 AM
Case 1; ambient file C:\Plumes20\Haines_Skagway_l_Jun05.006.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m
m/s
deg
psu
C kg/kg
s-1 m/s
deg m0.67/s2 sigma
-T
0.0
0.023
90.00
7.100
11.12
0.0 0.000194
0.023
90.00
0.0003 5.180276
1.523
0.023
90.00
14.16
10.08
0.0
0.000198
0.023
90.00
0.0003
10.78304
3.047
0.023
90.00
23.30
8.650
0.0
0.000197
0.023
90.00
0.0003
18.06627
4.570
0.023
90.00
23.25
8.670
0.0
0.000196
0.023
90.00
0.0003
18.02474
6.090
0.023
90.00
25.20
8.220
0.0
0.000196
0.023
90.00
0.0003
19.60292
7.617
0.023
90.00
26.37
8.020
0.0
0.000196
0.023
90.00
0.0003
20.54204
9.140
0.023
90.00
26.74
7.980
0.0
0.000196
0.023
90.00
0.0003
20.83621
10.45
0.023
90.00
27.46
7.570
0.0
0.000196
0.023
90.00
0.0003
21.45192
52
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
11.75
13.06
14.37
15.68
16.98
22.00
0.023
0.023
0.023
0.023
0.023
0.023
90.00
90.00
90.00
90.00
90.00
90.00
28.24
28.92
29.08
29.29
30.42
34.78
7.100
6.920
6.880
6.790
6.260
4.213
0.0 0.000196
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.023
0.023
0.023
0.023
0.023
0.023
90.00
90.00
90.00
90.00
90.00
90.00
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
22.12180
22.67724
22.80770
22.98359
23.93584
27.61629
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.0000 0.0 90.000 0.0 0.0 2.0000 15.000 42.600 200.00 21.100 2.9000 0.0 15.800
2.13E+6
Simulation:
Froude No:
22.84(m/s);
Depth Amb-cur
178.8; StratNo: 2.20E-3; Spcg No: 76.82; k: 992.9; eff den (sigmaT) -0.960860; eff vel
I.346
4.775
10.62
II.48
11.71
16.27
0.6058; 10.68 T-90hr,
1.9614
4.2261
4.5599
4.6475
P-dia Polutnt Dilutn x-posn y-posn Iso dia
(m) (cm/s) (in) (col/dl) () (m) (m) (m)
21.10 2.300 2.343 2.130E+6 1.000 0.0 0.0 0.05935; 10.68 T-90hr,
21.10 2.300 23.86 208749.0 10.20 0.000
21.03 2.300 77.28 63725.7 33.42 0.000
20.49 2.300 166.7 28847.1 73.76 0.000
20.37 2.300 179.9 26645.8 79.84 0.000
20.34 2.300 183.3 26122.1 81.44 0.000
19.97 2.300 305.7 21392.8 99.34 0.000
10.20 T-90hr,
Horiz plane projections in effluent direction: radius(m):
Lmz(m): 16.274
forced entrain 1 1.873 1.132 7.764 1.000
Rate sec-1 0.00019515 dy-1 16.8607 kt: 0.000062421 Amb Sal 33.0175
Const Eddy Diffusivity. Farfield dispersion based on wastefield width of 12.34 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
Step
0
100
160
200
204
205
232
bottom hit; 10.65 T-90hr,
10.42 T-90hr,
trap level; 10.37 T-90hr,
merging; 10.36 T-90hr,
7.7425; local maximum rise or fall;
0.0; CL(m): 16.274
(col/dl)
21392.8
19386.1
15243.7
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
99.34
118.7
136.7
12.34
23.00
30.62
16.27 2.78E-4
42.60 0.318
58.87 0.515
0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
5:20:07 AM. amb fills: 4
53
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 99.34
Estimated initial width (B) of plume after initial 12.34
dilution (meters)
Travel distance of plume after initial dilution 16.27
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
42.6
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.023
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
2.14E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
8.5548E-03
3.6170E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e (m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
0.317995
169
26.33
42.6
1.36E+02
1.56E+04
13/
54
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Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 6/23/2021 5:20:24 AM
Case 1; ambient file C:\Plumes20\Haines_Skagway_l_Jun05.006.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.023 90.00 7.100
I.523 0.023 90.00 14.16
3.047 0.023 90.00 23.30
4.570 0.023 90.00 23.25
6.090 0.023 90.00 25.20
7.617 0.023 90.00 26.37
9.140 0.023 90.00 26.74
10.45 0.023 90.00 27.46
II.75 0.023 90.00 28.24
13.06 0.023 90.00 28.92
14.37 0.023 90.00 29.08
15.68 0.023 90.00 29.29
16.98 0.023 90.00 30.42
22.00 0.023 90.00 34.78
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s
11.12
10.08
8.650
8.670
8.220
8.020
7.980
7.570
7.100
6.920
6.880
6.790
6.260
4.213
0.0 0.000194
0.0 0.000198
0.0 0.000197
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
deg
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
m0.67/s2 sigma-
90.00 0.0003 5
0.0003
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
27.61629
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.0000 0.0 90.000 0.0 0.0 2.0000 15.000 106.50 200.00 21.100 2.9000 0.0 15.800
2.13E+6
Simulation:
Froude No:
22.84(m/s);
Depth Amb-cur
178.8; StratNo: 2.20E-3; Spcg No: 76.82; k: 992.9; eff den (sigmaT) -0.960860; eff vel
I.346
4.775
10.62
II.48
11.71
16.27
0.6058; 10.68 T-90hr,
1.9614
4.2261
4.5599
4.6475
P-dia Polutnt Dilutn x-posn y-posn Iso dia
(m) (cm/s) (in) (col/dl) () (m) (m) (m)
21.10 2.300 2.343 2.130E+6 1.000 0.0 0.0 0.05935; 10.68 T-90hr,
21.10 2.300 23.86 208749.0 10.20 0.000
21.03 2.300 77.28 63725.7 33.42 0.000
20.49 2.300 166.7 28847.1 73.76 0.000
20.37 2.300 179.9 26645.8 79.84 0.000
20.34 2.300 183.3 26122.1 81.44 0.000
19.97 2.300 305.7 21392.8 99.34 0.000
10.20 T-90hr,
Horiz plane projections in effluent direction: radius(m):
Lmz(m): 16.274
forced entrain 1 1.873 1.132 7.764 1.000
Rate sec-1 0.00019515 dy-1 16.8607 kt: 0.000062421 Amb Sal 33.0175
Const Eddy Diffusivity. Farfield dispersion based on wastefield width of 12.34 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
Step
0
100
160
200
204
205
232
bottom hit; 10.65 T-90hr,
10.42 T-90hr,
trap level; 10.37 T-90hr,
merging; 10.36 T-90hr,
7.7425; local maximum rise or fall;
0.0; CL(m): 16.274
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
21392.8 99.34 12.34 16.27 2.78E-4 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
16299.5 181.1 56.68 106.5 1.090 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
10795.8 194.1 66.75 122.8 1.287 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
count: 1
5:20:24 AM. amb fills: 4
56
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
The initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width)4/3.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 99.34
Estimated initial width (B) of plume after initial 12.34
dilution (meters)
Travel distance of plume after initial dilution 16.27
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
106.5
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.023
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
2.14E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
8.5548E-03
3.6170E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e (m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
1.089734
3
90.23
106.5
3.30E+02
6.43E+03
331
57
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
/ UM3. 6/23/2021 5:20:41 AM
Case 1; ambient file C:\Plumes20\Haines_Skagway_l_Jun05.006.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.023 90.00 7.100
I.523 0.023 90.00 14.16
3.047 0.023 90.00 23.30
4.570 0.023 90.00 23.25
6.090 0.023 90.00 25.20
7.617 0.023 90.00 26.37
9.140 0.023 90.00 26.74
10.45 0.023 90.00 27.46
II.75 0.023 90.00 28.24
13.06 0.023 90.00 28.92
14.37 0.023 90.00 29.08
15.68 0.023 90.00 29.29
16.98 0.023 90.00 30.42
22.00 0.023 90.00 34.78
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1
m/s
11.12
10.08
8.650
8.670
8.220
8.020
7.980
7.570
7.100
6.920
6.880
6.790
6.260
4.213
0.0 0.000194
0.0 0.000198
0.0 0.000197
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
deg
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
0.023
m0.67/s2 sigma-
90.00 0.0003 5
0.0003
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
27.61629
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.0000 0.0 90.000 0.0 0.0 2.0000 15.000 213.00 200.00 21.100 2.9000 0.0 15.800
2.13E+6
Simulation:
Froude No: 178.8; StratNo: 2.20E-3; Spcg No: 76.82; k: 992.9; eff den (sigmaT) -0.960860; eff vel
22.84(m/s);
Depth Amb-cur P-dia Polutnt Dilutn x-posn y-posn Iso dia
Step
(m)
(cm/s)
(in) (col/dl) 0
(m)
(m)
(m)
0
21.10
2.300
2.343 2.130E+6
1.000
0.0
0.0 0.05935; 10.68 T-90hr,
100
21.10
2.300
23.86 208749.0
10.20
0.000
1.346
0.6058; 10.68 T-90hr,
160
21.03
2.300
77.28 63725.7
33.42
0.000
4.775
1.9614; bottom hit; 10.65 T-90hr,
200
20.49
2.300
166.7 28847.1
73.76
0.000
10.62
4.2261; 10.42 T-90hr,
204
20.37
2.300
179.9 26645.8
79.84
0.000
11.48
4.5599; trap level; 10.37 T-90hr,
205
20.34
2.300
183.3 26122.1
81.44
0.000
11.71
4.6475; merging; 10.36 T-90hr,
232
19.97
2.300
305.7 21392.8
99.34
0.000
16.27
7.7425; local maximum rise or fall;
10.20
T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.0; CL(m): 16.274
Lmz(m): 16.274
forced entrain 1 1.873 1.132 7.764 1.000
Rate sec-1 0.00019515 dy-1 16.8607 kt: 0.000062421 Amb Sal 33.0175
Const Eddy Diffusivity. Farfield dispersion based on wastefield width of 12.34 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
21392.8 99.34 12.34 16.27 2.78E-4 0.0 16.27 2.300 90.00 3.00E-4 6.2421E-5
58
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
12646.5 246.9 121.4 200.0 2.219 0.0 16.27 2.300
8191.65 256.7 134.2 216.3 2.416 0.0 16.27 2.300
count: 1
90.00 3.00E-4 6.2421E-5
90.00 3.00E-4 6.2421E-5
5:20:41 AM. amb fills: 4
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 99.34
Estimated initial width (B) of plume after initial 12.34
dilution (meters)
Travel distance of plume after initial dilution 16.27
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
213
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.023
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day-1)
2.14E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Bftta =
8.5548E-03
3.6170E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e (m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
2.375966
184
196.73
213
7.66E+02
2.77E+03
768
59
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Ketchikan (model output for l*depth, 2*depth, 5*depth and 10*depth)
Contents of the memo box (may not be current and must be updated manually)
Project "C:\Plumes20\Ketchikan_lport" memo
Model configuration items checked: Brooks far-field solution;
Channel width (m) 100
Start case for graphs 1
Max detailed graphs 10 (limits plots that can overflow memory)
Elevation Projection Plane (deg) 0
Shore vector (m,deg) not checked
Bacteria model : Mancini (1978) coliform model
PDS sfc. model heat transfer : Medium
Equation of State : S, T
Similarity Profile : Default profile (k=2.0, ...)
Diffuser port contraction coefficient 0.61
Light absorption coefficient 0.16
Farfield increment (m) 200
UM3 aspiration coefficient 0.1
Output file: text output tab
Output each ?? steps 100
Maximum dilution reported 100000
Text output format: Standard
Max vertical reversals : to max rise or fall
/ UM3. 6/23/2021 5:27:49 AM
Case 1; ambient file C:\Plumes20\Ketchikan_3_Julyl997.004.db; Diffuser table record 3:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m m/s
0.0 0.059
1.000 0.059
16.10 0.059
33.90 0.059
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports MZ-dis Isoplth P-depth Ttl-flo Eff-sal Temp
Polutnt
(in) (deg) (deg) (m) (m) () (m)(concent) (m) (MGD) (psu) (C)(col/dl)
12.000 0.0 205.00 0.0 0.0 1.0000 29.900 100.00 29.600 3.4560 0.0 20.500 20000.0
Simulation:
Froude No: 14.08; StratNo: 1.68E-3; Spcg No: 9.00E+8; k: 57.66; eff den (sigmaT) -1.837438; eff
vel 3.402(m/s);
Depth Amb-cur P-dia Polutnt Dilutn x-posn y-posn Time Iso dia
Step (m) (cm/s) (in) (col/dl) () (m) (m) (s) (m)
0 29.60 5.900 9.372 20000.0 1.000 0.0 0.0 0.0 0.2374; 13.41 T-90hr,
100 29.37 5.900 61.18 2975.1 6.722 -2.606 -1.081 3.096 1.5410; 13.32 T-90hr,
deg psu C kg/kg s-1 m/s deg m0.67/s2 sigma-T
140.0 24.50 15.20 0.0 0.000196 0.059 140.0 0.0003 17.89918
140.0 24.50 15.20 0.0 0.0002 0.059 140.0 0.0003 17.89918
140.0 26.80 13.80 0.0 0.0002 0.059 140.0 0.0003 19.93814
140.0 30.90 8.000 0.0 0.000199 0.059 140.0 0.0003 24.08526
60
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
200
27.61
5.900
135.6
1142.4
17.50 -6.017 -2.060
14.40
249
24.16
5.900
233.0
562.5
35.49 -9.308 -2.435
34.83
276
22.92
5.900
300.9
445.7
44.77 -10.56 -2.414
45.33
90hr,
300
22.48
5.900
333.7
414.4
48.13 -11.13 -2.377
50.59
400
21.94
5.900
383.7
388.9
51.25 -12.54 -2.254
64.07
417
21.94
5.900
385.5
387.6
51.42 -12.73 -2.235
65.91
3.3681; 12.62 T-90hr,
5.6507; trap level; 11.26 T-90hr,
7.2032; begin overlap; 10.77 T-
7.9496; 10.60 T-90hr,
9.1014; 10.40 T-90hr,
9.1403; local maximum rise or
fall; 10.39 T-90hr,
Horiz plane projections in effluent direction: radius(m): 2.4839; CL(m): 12.480
Lmz(m): 14.964
forced entrain 1 1.28E+9 7.663 9.791 1.000
Rate sec-1 0.00019971 dy-1 17.2550 kt: 0.000059972 Amb Sal 28.1446
4/3 Power Law. Farfield dispersion based on wastefield width of 9.79 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
387.592 51.42 9.799 12.92 2.78E-4 0.0 16.00 5.900 140.0 3.00E-4 5.9972E-5
372.140 52.31 12.10 29.90 0.0802 0.0 16.00 5.900 140.0 3.00E-4 5.9972E-5
346.023 56.38 13.95 42.82 0.141 0.0 16.00 5.900 140.0 3.00E-4 5.9972E-5
count: 1
5:27:49 AM. amb fills: 4
61
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 51.42
Estimated initial width (B) of plume after initial 9.79
dilution (meters)
Travel distance of plume after initial dilution 12.92
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
29.9
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.42E-
04
4. Horizontal current speed (m/sec)
0.059
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
3.88E+
02
2.00E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.2830E-03
1.3053E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
7.99E-02
16.98
29.90
5.22E+01
3.82E+02
52
62
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 6/23/2021 5:28:05 AM
Case 1; ambient file C:\Plumes20\Ketchikan_3_Julyl997.004.db; Diffuser table record 3:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.059 140.0 24.50
1.000 0.059 140.0 24.50
16.10 0.059 140.0 26.80
33.90 0.059 140.0 30.90
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s deg m0.67/s2 sigma-T
15.20 0.0 0.000195 0.059 140.0 0.0003 17.89918
15.20 0.0 0.0002 0.059 140.0 0.0003 17.89918
13.80 0.0 0.0002 0.059 140.0 0.0003 19.93814
8.000 0.0 0.000199 0.059 140.0 0.0003 24.08526
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports MZ-dis Isoplth P-depth Ttl-flo Eff-sal Temp
Polutnt
(in) (deg) (deg) (m) (m) () (m)(concent) (m) (MGD) (psu) (C)(col/dl)
12.000 0.0 205.00 0.0 0.0 1.0000 59.800 100.00 29.600 3.4560 0.0 20.500 20000.0
Simulation:
FroudeNo: 14.08; StratNo: 1.68E-3; Spcg No: 9.00E+8; k:
vel 3.402(m/s);
P-dia Polutnt
(in) (col/dl)
9.372 20000.0
61.18 2975.1
57.66; eff den (sigmaT) -1.837438; eff
Depth Amb-cur
Step
0
100
200
249
276
90hr,
300
400
417
fall;
(m)
29.60
29.37
27.61
24.16
22.92
22.48
21.94
21.94
(cm/s)
5.900
5.900
5.900
5.900
5.900
5.900
5.900
5.900
Dilutn x-posn y-posn Time
0 (m) (m) (s) (m)
Iso dia
135.6
233.0
300.9
333.7
383.7
385.5
1142.4
562.5
445.7
414.4
388.9
387.6
1.000
6.722
17.50
35.49
44.77
48.13
51.25
51.42
0.0 0.0 0.2222; 13.41 T-90hr,
0.0
-2.606 -1.081 3.096 1.5410; 13.32 T-90hr,
-6.017 -2.060 14.40 3.3681; 12.62 T-90hr,
-9.308 -2.435 34.83 5.6507; trap level; 11.26 T-90hr,
-10.56 -2.414 45.33 7.2032; begin overlap; 10.77 T-
-11.13 -2.377 50.59 7.9496; 10.60 T-90hr,
-12.54 -2.254 64.07 9.1014; 10.40 T-90hr,
-12.73 -2.235 65.91 9.1403; local maximum rise or
10.39 T-90hr,
Horiz plane projections in effluent direction: radius(m): 2.4839; CL(m): 12.480
Lmz(m): 14.964
forced entrain 1 1.28E+9 7.663 9.791 1.000
Rate sec-1 0.00019971 dy-1 17.2550 kt: 0.000059972 Amb Sal 28.1446
4/3 Power Law. Farfield dispersion based on wastefield width of 9.79 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
387.592
361.000
273.501
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
51.42 9.799 12.92 2.78E-4 0.0 16.00 5.900
64.47 16.52 59.80 0.221 0.0 16.00 5.900
71.65 18.57 72.72 0.282 0.0 16.00 5.900
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
63
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 51.42
Estimated initial width (B) of plume after initial 9.79
dilution (meters)
Travel distance of plume after initial dilution 12.92
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
59.8
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.42E-
04
4. Horizontal current speed (m/sec)
0.059
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
3.88E+
02
2.00E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.2830E-03
1.3053E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
2.21 E-01
46.88
59.80
6.24E+01
3.19E+02
63
64
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
5:28:05 AM. amb fills: 4
/ UM3. 6/23/2021 5:28:34 AM
Case 1; ambient file C:\Plumes20\Ketchikan_3_Julyl997.004.db; Diffuser table record 3:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.059 140.0 24.50
1.000 0.059 140.0 24.50
16.10 0.059 140.0 26.80
33.90 0.059 140.0 30.90
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s deg m0.67/s2 sigma-T
15.20 0.0 0.000195 0.059 140.0 0.0003 17.89918
15.20 0.0 0.0002 0.059 140.0 0.0003 17.89918
13.80 0.0 0.0002 0.059 140.0 0.0003 19.93814
8.000 0.0 0.000199 0.059 140.0 0.0003 24.08526
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports MZ-dis Isoplth P-depth Ttl-flo Eff-sal Temp
Polutnt
(in) (deg) (deg) (m) (m) () (m)(concent) (m) (MGD) (psu) (C)(col/dl)
12.000 0.0 205.00 0.0 0.0 1.0000 149.50 100.00 29.600 3.4560 0.0 20.500 20000.0
Simulation:
FroudeNo: 14.08; StratNo: 1.68E-3; Spcg No: 9.00E+8; k:
vel 3.402(m/s);
P-dia Polutnt
(in) (col/dl)
9.372 20000.0
61.18 2975.1
57.66; eff den (sigmaT) -1.837438; eff
Depth Amb-cur
Step
0
100
200
249
276
90hr,
300
400
417
fall;
(m)
29.60
29.37
27.61
24.16
22.92
22.48
21.94
21.94
(cm/s)
5.900
5.900
5.900
5.900
5.900
5.900
5.900
5.900
Dilutn x-posn y-posn Time
0 (m) (m) (s) (m)
Iso dia
135.6
233.0
300.9
333.7
383.7
385.5
1142.4
562.5
445.7
414.4
388.9
387.6
1.000
6.722
17.50
35.49
44.77
48.13
51.25
51.42
0.0 0.0 0.2222; 13.41 T-90hr,
0.0
-2.606 -1.081 3.096 1.5410; 13.32 T-90hr,
-6.017 -2.060 14.40 3.3681; 12.62 T-90hr,
-9.308 -2.435 34.83 5.6507; trap level; 11.26 T-90hr,
-10.56 -2.414 45.33 7.2032; begin overlap; 10.77 T-
-11.13 -2.377 50.59 7.9496; 10.60 T-90hr,
-12.54 -2.254 64.07 9.1014; 10.40 T-90hr,
-12.73 -2.235 65.91 9.1403; local maximum rise or
10.39 T-90hr,
Horiz plane projections in effluent direction: radius(m): 2.4839; CL(m): 12.480
Lmz(m): 14.964
forced entrain 1 1.28E+9 7.663 9.791 1.000
Rate sec-1 0.00019971 dy-1 17.2550 kt: 0.000059972 Amb Sal 28.1446
4/3 Power Law. Farfield dispersion based on wastefield width of 9.79 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
387.592
329.541
149.151
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
51.42
122.8
132.4
9.799
32.26
34.81
12.92 2.78E-4
149.5 0.643
162.4 0.704
0.0 16.00 5.900
0.0 16.00 5.900
0.0 16.00 5.900
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
5:28:34 AM. amb fills: 4
65
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 51.42
Estimated initial width (B) of plume after initial 9.79
dilution (meters)
Travel distance of plume after initial dilution 12.92
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
149.5
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.42E-
04
4. Horizontal current speed (m/sec)
0.059
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
3.88E+
02
2.00E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.2830E-03
1.3053E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
6.43E-01
136.58
149.50
1.05E+02
1.89E+02
106
66
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
/ UM3. 6/23/2021 5:28:46 AM
Case 1; ambient file C:\Plumes20\Ketchikan_3_Julyl997.004.db; Diffuser table record 3:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.059 140.0 24.50
1.000 0.059 140.0 24.50
16.10 0.059 140.0 26.80
33.90 0.059 140.0 30.90
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s deg m0.67/s2 sigma-T
15.20 0.0 0.000195 0.059 140.0 0.0003 17.89918
15.20 0.0 0.0002 0.059 140.0 0.0003 17.89918
13.80 0.0 0.0002 0.059 140.0 0.0003 19.93814
8.000 0.0 0.000199 0.059 140.0 0.0003 24.08526
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports MZ-dis Isoplth P-depth Ttl-flo Eff-sal Temp
Polutnt
(in) (deg) (deg) (m) (m) () (m)(concent) (m) (MGD) (psu) (C)(col/dl)
12.000 0.0 205.00 0.0 0.0 1.0000 299.00 100.00 29.600 3.4560 0.0 20.500 20000.0
Simulation:
FroudeNo: 14.08; StratNo: 1.68E-3; Spcg No: 9.00E+8; k:
vel 3.402(m/s);
P-dia Polutnt
(in) (col/dl)
9.372 20000.0
61.18 2975.1
57.66; eff den (sigmaT) -1.837438; eff
Depth Amb-cur
Step
0
100
200
249
276
90hr,
300
400
417
fall;
(m)
29.60
29.37
27.61
24.16
22.92
22.48
21.94
21.94
(cm/s)
5.900
5.900
5.900
5.900
5.900
5.900
5.900
5.900
Dilutn x-posn y-posn Time
0 (m) (m) (s) (m)
Iso dia
135.6
233.0
300.9
333.7
383.7
385.5
1142.4
562.5
445.7
414.4
388.9
387.6
1.000
6.722
17.50
35.49
44.77
48.13
51.25
51.42
0.0 0.0 0.2222; 13.41 T-90hr,
0.0
-2.606 -1.081 3.096 1.5410; 13.32 T-90hr,
-6.017 -2.060 14.40 3.3681; 12.62 T-90hr,
-9.308 -2.435 34.83 5.6507; trap level; 11.26 T-90hr,
-10.56 -2.414 45.33 7.2032; begin overlap; 10.77 T-
-11.13 -2.377 50.59 7.9496; 10.60 T-90hr,
-12.54 -2.254 64.07 9.1014; 10.40 T-90hr,
-12.73 -2.235 65.91 9.1403; local maximum rise or
10.39 T-90hr,
Horiz plane projections in effluent direction: radius(m): 2.4839; CL(m): 12.480
Lmz(m): 14.964
forced entrain 1 1.28E+9 7.663 9.791 1.000
Rate sec-1 0.00019971 dy-1 17.2550 kt: 0.000059972 Amb Sal 28.1446
4/3 Power Law. Farfield dispersion based on wastefield width of 9.79 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
387.592
313.051
94.9421
54.9006
count: 2
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
51.42
161.8
348.2
361.8
9.799
42.56
91.63
95.21
12.92 2.78E-4
200.0 0.881
400.0
412.9
1.823
1.884
0.0 16.00 5.900
0.0 16.00 5.900
0.0 16.00 5.900
0.0 16.00 5.900
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
140.0 3.00E-4 5.9972E-5
67
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 51.42
Estimated initial width (B) of plume after initial 9.79
dilution (meters)
Travel distance of plume after initial dilution 12.92
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
299
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.42E-
04
4. Horizontal current speed (m/sec)
0.059
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
3.88E+
02
2.00E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.2830E-03
1.3053E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
1.35E+00
286.08
299.00
1.79E+02
1.11E+02
180
68
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Petersburg (model output for l*depth, 2*depth, 5*depth and 10*depth)
Contents of the memo box (may not be current and must be updated manually)
Project "C:\Plumes20\Petersburg" me
Model configuration items checked: Brooks far-field solution;
Channel width (m) 100
Start case for graphs 1
Max detailed graphs 10 (limits plots that can overflow memory)
Elevation Projection Plane (deg) 0
Shore vector (m,deg) not checked
Bacteria model : Mancini (1978) coliform model
PDS sfc. model heat transfer : Medium
Equation of State : S, T
Similarity Profile : Default profile (k=2.0, ...)
Diffuser port contraction coefficient 0.61
Light absorption coefficient 0.16
Farfield increment (m) 200
UM3 aspiration coefficient 0.1
Output file: text output tab
Output each ?? steps 100
Maximum dilution reported 100000
Text output format: Standard
Max vertical reversals : to max rise or fall
/ UM3. 6/23/2021 5:40:38 AM
Case 1; ambient file C:\Plumes20\Petersburg_l_Aug05.002.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m m/s
0.0 0.016
9.150 0.016
18.29 0.016
20.00 0.016
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
4.0000 0.0 115.00 0.0 0.0 2.0000 10.000 18.300 200.00 18.070 3.6000 0.0 14.600
2.02E+6
Simulation:
Froude No: 114.5; StratNo: 7.46E-4; Spcg No: 38.41; k: 996.7; eff den (sigmaT) -0.776899; eff vel
15.95(m/s);
Depth Amb-cur P-dia Polutnt Dilutn x-posn y-posn Time Iso dia
Step (m) (cm/s) (in) (col/dl) () (m) (m) (s) (m)
0 18.07 1.600 3.124 2.020E+6 1.000 0.0 0.0 0.0 0.0746; 9.342 T-90hr,
deg psu C kg/kg s-1 m/s deg m0.67/s2 sigma-T
120.0 25.80 9.500 0.0 0.000195 0.016 120.0 0.0003 19.89413
120.0 28.10 8.200 0.0 0.000196 0.016 120.0 0.0003 21.86897
120.0 30.90 7.300 0.0 0.000196 0.016 120.0 0.0003 24.18118
120.0 31.42 7.132 0.0 0.000195 0.016 120.0 0.0003 24.61448
69
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
100
18.07
1.600
27.00 233103.2
8.665 -0.637
1.364
0.470
0.6855; 9.340 T-90hr,
177
17.70
1.600
121.5
50815.2
39.73 -3.202
6.837
9.667
3.0831; merging; 9.198 T-90hr,
200
16.92
1.600
192.0
38804.9
51.98 -4.867
10.37
20.86
4.8693; 8.895 T-90hr,
212
15.74
1.600
258.0
32719.8
61.58 -6.629
14.10
35.23
6.5408; trap level; 8.436 T-
90hr,
221
14.97
1.600
323.8
29956.8
67.21 -7.796
16.57
45.91
8.2053; MZ dis; 8.143 T-90hr,
forced entrain 1 1.914 3.095 8.224 0.970
Rate sec-1 0.00019604 dy-1 16.9376 kt: 0.000077955 Amb Sal 29.8950
Mixing Zone reached in near-field, no far-field calculation attempted
5:40:38 AM. amb fills: 4
/ UM3. 6/23/2021 5:40:52 AM
Case 1; ambient file C:\Plumes20\Petersburg_l_Aug05.002.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.016 120.0 25.80
9.150 0.016 120.0 28.10
18.29 0.016 120.0 30.90
20.00 0.016 120.0 31.42
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s deg m0.67/s2 sigma-T
9.500 0.0 0.000195 0.016 120.0 0.0003 19.89413
8.200 0.0 0.000196 0.016 120.0 0.0003 21.86897
7.300 0.0 0.000196 0.016 120.0 0.0003 24.18118
7.132 0.0 0.000195 0.016 120.0 0.0003 24.61448
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
4.0000 0.0 115.00 0.0 0.0 2.0000 10.000 36.600 200.00 18.070 3.6000 0.0 14.600
2.02E+6
Simulation:
Froude No: 114.5; StratNo: 7.46E-4; Spcg No: 38.41; k: 996.7; eff den (sigmaT) -0.776899; eff vel
15.95(m/s);
Depth Amb-cur
Step
0
100
177
200
212
90hr.
269
(m)
18.07
18.07
17.70
16.92
15.74
(cm/s)
1.600
1.600
1.600
1.600
1.600
P-dia Polutnt
(in) (col/dl)
3.124 2.020E+6
27.00 233103.2
121.5 50815.2
192.0 38804.9
258.0 32719.8
Dilutn x-posn
0 (m) (m)
1.000 0.0
8.665 -0.637
39.73 -3.202
51.98 -4.867
61.58 -6.629
Iso dia
y-posn Time
(s) (m)
0.0 0.0 0.07918;
9.342 T-90hr,
1.364 0.470 0.6855; 9.340 T-90hr,
6.837 9.667 3.0831; merging; 9.198 T-90hr,
10.37 20.86 4.8693; 8.895 T-90hr,
14.10 35.23 6.5408; trap level; 8.436 T-
14.43 1.600
74.42 -9.596 20.37 63.81 10.443; local maximum rise or
22.520
412.1 27015.9
fall; 7.935 T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.03203; CL(m):
Lmz(m): 22.552
forced entrain 1 2.252 3.642 10.47 1.000
Rate sec-1 0.00019608 dy-1 16.9412 kt: 0.000080118 Amb Sal 29.7168
4/3 Power Law. Farfield dispersion based on wastefield width of 13.51 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
70
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
27015.9 74.42 13.51
24577.8 89.58 21.72
13316.6 149.2 37.30
count: 1
22.52 2.78E-4 0.0 16.25 1.600 120.0 3.00E-4 8.0118E-5
36.60 0.245 0.0 16.25 1.600 120.0 3.00E-4 8.0118E-5
59.12 0.636 0.0 16.25 1.600 120.0 3.00E-4 8.0118E-5
5:40:52 AM. amb fills: 4
/ UM3. 6/23/2021 5:41:05 AM
Case 1; ambient file C:\Plumes20\Petersburg_l_Aug05.002.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.016 120.0 25.80
9.150 0.016 120.0 28.10
18.29 0.016 120.0 30.90
20.00 0.016 120.0 31.42
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s deg m0.67/s2 sigma-T
9.500 0.0 0.000195 0.016 120.0 0.0003 19.89413
8.200 0.0 0.000196 0.016 120.0 0.0003 21.86897
7.300 0.0 0.000196 0.016 120.0 0.0003 24.18118
7.132 0.0 0.000195 0.016 120.0 0.0003 24.61448
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
4.0000 0.0 115.00 0.0 0.0 2.0000 10.000 91.500 200.00 18.070 3.6000 0.0 14.600
2.02E+6
Simulation:
Froude No: 114.5; StratNo: 7.46E-4; Spcg No: 38.41; k: 996.7; eff den (sigmaT) -0.776899; eff vel
15.95(m/s);
Depth Amb-cur
Step
0
100
177
200
212
90hr.
269
(m)
18.07
18.07
17.70
16.92
15.74
(cm/s)
1.600
1.600
1.600
1.600
1.600
P-dia Polutnt
(in) (col/dl)
3.124 2.020E+6
27.00 233103.2
121.5 50815.2
192.0 38804.9
258.0 32719.8
Dilutn x-posn
0 (m) (m)
1.000 0.0
8.665 -0.637
39.73 -3.202
51.98 -4.867
61.58 -6.629
Iso dia
y-posn Time
(s) (m)
0.0 0.0 0.07916;
9.342 T-90hr,
1.364 0.470 0.6855; 9.340 T-90hr,
6.837 9.667 3.0831; merging; 9.198 T-90hr,
10.37 20.86 4.8693; 8.895 T-90hr,
14.10 35.23 6.5408; trap level; 8.436 T-
14.43 1.600
74.42 -9.596 20.37 63.81 10.443; local maximum rise or
22.520
412.1 27015.9
fall; 7.935 T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.03203; CL(m):
Lmz(m): 22.552
forced entrain 1 2.252 3.642 10.47 1.000
Rate sec-1 0.00019608 dy-1 16.9412 kt: 0.000080118 Amb Sal 29.7168
4/3 Power Law. Farfield dispersion based on wastefield width of 13.51 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
27015.9
18670.4
5869.71
count: 1
; 5:41:06 AM. amb fills: 4
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
74.42 13.51 22.52 2.78E-4 0.0 16.25 1.600 120.0 3.00E-4 8.0118E-5
255.8 64.12 91.50 1.198 0.0 16.25 1.600 120.0 3.00E-4 8.0118E-5
340.7 85.44 114.0 1.589 0.0 16.25 1.600 120.0 3.00E-4 8.0118E-5
71
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 74.42
Estimated initial width (B) of plume after initial 13.51
dilution (meters)
Travel distance of plume after initial dilution 22.52
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
91.5
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.016
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
2.70E+
04
1.96E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
9.6530E-03
5.3588E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e (m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
1.197569
444
68.98
91.5
2.56E+02
7.86E+03
257
72
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
/ UM3. 6/23/2021 5:41:17 AM
Case 1; ambient file C:\Plumes20\Petersburg_l_Aug05.002.db; Diffuser table record 1:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.016 120.0 25.80
9.150 0.016 120.0 28.10
18.29 0.016 120.0 30.90
20.00 0.016 120.0 31.42
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s deg m0.67/s2 sigma-T
9.500 0.0 0.000195 0.016 120.0 0.0003 19.89413
8.200 0.0 0.000196 0.016 120.0 0.0003 21.86897
7.300 0.0 0.000196 0.016 120.0 0.0003 24.18118
7.132 0.0 0.000195 0.016 120.0 0.0003 24.61448
Diffuser table:
P-diaVer angl H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
4.0000 0.0 115.00 0.0 0.0 2.0000 10.000 183.00 200.00 18.070 3.6000 0.0 14.600
2.02E+6
Simulation:
Froude No: 114.5; StratNo: 7.46E-4; Spcg No: 38.41; k: 996.7; eff den (sigmaT) -0.776899; eff vel
15.95(m/s);
Depth Amb-cur
Step
0
100
177
200
212
90hr.
269
(m)
18.07
18.07
17.70
16.92
15.74
(cm/s)
1.600
1.600
1.600
1.600
1.600
P-dia Polutnt
(in) (col/dl)
3.124 2.020E+6
27.00 233103.2
121.5 50815.2
192.0 38804.9
258.0 32719.8
Dilutn x-posn
0 (m) (m)
1.000 0.0
8.665 -0.637
39.73 -3.202
51.98 -4.867
61.58 -6.629
Iso dia
y-posn Time
(s) (m)
0.0 0.0 0.07916;
9.342 T-90hr,
1.364 0.470 0.6855; 9.340 T-90hr,
6.837 9.667 3.0831; merging; 9.198 T-90hr,
10.37 20.86 4.8693; 8.895 T-90hr,
14.10 35.23 6.5408; trap level; 8.436 T-
14.43 1.600
74.42 -9.596 20.37 63.81 10.443; local maximum rise or
22.520
412.1 27015.9
fall; 7.935 T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.03203; CL(m):
Lmz(m): 22.552
forced entrain 1 2.252 3.642 10.47 1.000
Rate sec-1 0.00019608 dy-1 16.9412 kt: 0.000080118 Amb Sal 29.7168
4/3 Power Law. Farfield dispersion based on wastefield width of 13.51 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
27015.9
11807.9
2638.61
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
74.42
646.9
760.1
13.51
162.2
190.6
22.52 2.78E-4
183.0
205.5
2.786
3.177
0.0
0.0
0.0
16.25 1.600
16.25 1.600
16.25 1.600
120.0 3.00E-4 8.0118E-5
120.0 3.00E-4 8.0118E-5
120.0 3.00E-4 8.0118E-5
5:41:17 AM. amb fills: 4
73
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 74.42
Estimated initial width (B) of plume after initial 13.51
dilution (meters)
Travel distance of plume after initial dilution 22.52
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
183
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.016
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
2.70E+
04
1.96E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
9.6530E-03
5.3588E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e (m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
2.786111
111
160.48
183
6.47E+02
3.11E+03
650
74
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Sitka (model output for l*depth, 2*depth, 5*depth and 10*depth)
Contents of the memo box (may not be current and must be updated manually)
Project "C:\Plumes20\Sitka" memo
Model configuration items checked: Brooks far-field solution; Report effective dilution;;
Channel width (m) 100
Start case for graphs 1
Max detailed graphs 10 (limits plots that can overflow memory)
Elevation Projection Plane (deg) 0
Shore vector (m,deg) not checked
Bacteria model : Mancini (1978) coliform model
PDS sfc. model heat transfer : Medium
Equation of State : S, T
Similarity Profile : Default profile (k=2.0, ...)
Diffuser port contraction coefficient 1
Light absorption coefficient 0.16
Farfield increment (m) 100
UM3 aspiration coefficient 0.1
Output file: text output tab
Output each ?? steps 100
Maximum dilution reported 100000
Text output format: Standard
Max vertical reversals : to max rise or fall
/ uDKHLRD; for extra details examine output file \Plumes20\dkhwisp.out
Case 1; ambient file C:\Plumes20\Sitka_C_Jull0.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m
m/s
deg
psu
C kg/kg
s-1 m/s
deg m0.67/s2 sigma-T
0.0
0.017
225.0
26.60
12.70
0.0 0.000196
0.017
225.0
0.0003 19.98988
1.000
0.017
225.0
26.60
12.70
0.0
0.000198
0.017
225.0
0.0003 19.98988
5.000
0.017
225.0
28.20
12.20
0.0
0.000198
0.017
225.0
0.0003 21.31369
10.00
0.017
225.0
29.10
11.60
0.0
0.000198
0.017
225.0
0.0003 22.11543
15.00
0.017
225.0
29.60
10.60
0.0
0.000197
0.017
225.0
0.0003 22.67329
20.00
0.017
225.0
29.80
9.800
0.0
0.000197
0.017
225.0
0.0003 22.95817
25.00
0.017
225.0
29.90
9.500
0.0
0.000196
0.017
225.0
0.0003 23.08290
30.00
0.017
225.0
29.90
9.100
0.0
0.000196
0.017
225.0
0.0003 23.14401
Diffuser table:
P-dia VertAng H-Angle SourceX
SourceY
Ports
Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
4.0000 0.0 300.00 0.0 0.0 16.000 13.000 24.400 200.00 23.940 5.3000 0.0 15.000
3.74E+6
Simulation:
75
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
FroudeNo: 11.60; StratNo: 5.45E-4; Spcg No: 39.00; k: 105.3; eff den (sigmaT) -0.836341; eff vel
1.790(m/s);
Depth Amb-cur P-dia Polutnt net Dil x-posn y-posn Time Iso dia
(in) (col/dl) () (m) (m) (s) (m)
4.000 3.740E+6 0.0 0.0 0.0 0.0 0.1014; 11.44 T-90hr,
4.000 3.740E+6 1.000 0.0 0.0 0.0 0.1016; 11.44 T-90hr,
10.94 1.929E+6 1.939 -0.497 0.285 0.320 0.2780; 11.43 T-90hr,
14.30 1.472E+6 2.540 -0.585 0.334 0.385 0.3632; 11.43 T-90hr,
21.15 988111.0 3.785 -0.763 0.432 0.566 0.5372; 11.42 T-90hr,
28.20 733621.0 5.098 -0.940 0.527 0.820 0.7162; 11.41 T-90hr,
38.91 519516.6 7.199 -1.202 0.662 1.331 0.9883; 11.38 T-90hr,
Step
(m)
(cm/s)
0
23.94
1.700
1
23.94
1.700
2
23.93
1.700
3
23.92
1.700
5
23.90
1.700
7
23.87
1.700
9
23.80
1.700
11
23.64
1.700
13
23.42
1.700
17
22.83
1.700
21
22.14
1.700
27
21.03
1.700
55
19.66
1.700
67
17.85
1.700
79
15.49
1.700
133
12.24
1.700
151
9.808
1.700
11.32 T-90hr,
merging; 11.24T-90hr,
11.01 T-90hr,
10.75 T-90hr,
10.33 T-90hr,
52.78 364415.9 10.26 -1.539 0.825 2.240 1.3405
63.65 283591.1 13.19 -1.848 0.963 3.349 1.6165
76.78 206140.1 18.14 -2.365 1.164 5.764 1.9498
87.81 163240.4 22.91 -2.776 1.297 8.271 2.2298
104.8 125663.6 29.76 -3.270 1.419 12.28 2.6616
131.6 99789.2 37.48 -3.747 1.497 17.53 3.3416; 9.805 T-90hr,
164.7 79160.1 47.25 -4.268 1.537 24.48 4.1811; 9.113 T-90hr,
218.5 62651.8 59.70 -4.873 1.525 33.78 5.5450; 8.222 T-90hr,
351.2 49337.1 75.81 -5.704 1.423 48.38 8.9048; 7.033 T-90hr,
947.0 43327.2 86.32 -6.744 1.206 68.20 24.008; 6.180 T-90hr,
4/3 Power Law. Farfield dispersion based on wastefield width of 83.49 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
43327.2 86.32 83.51 6.851 2.78E-4 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
3.53E+6 87.12 100.3 24.40 0.287 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
9.94E+5 89.08 107.1 31.25 0.399 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
count: 1
76
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 86.32
Estimated initial width (B) of plume after initial 83.49
dilution (meters)
Travel distance of plume after initial dilution 6.851
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
24.4
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
1.31E-
03
4. Horizontal current speed (m/sec)
0.017
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
4.33E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
1.0947E-01
9.2555E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
2.87E-01
17.549
24.40
8.70E+01
4.30E+04
87
77
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
/ uDKHLRD; for extra details examine output file \Plumes20\dkhwisp.out
Case 1; ambient file C:\Plumes20\Sitka_C_Jull0.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg
0.0 0.017 225.0
1.000 0.017 225.0
5.000 0.017 225.0
10.00 0.017 225.0
15.00 0.017 225.0
20.00 0.017 225.0
25.00 0.017 225.0
30.00 0.017 225.0
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
psu C kg/kg s-1 m/s deg m0.67/s2 sigma-T
26.60 12.70 0.0 0.000196 0.017 225.0 0.0003 19.98988
26.60 12.70 0.0 0.000198 0.017 225.0 0.0003 19.98988
28.20 12.20 0.0 0.000198 0.017 225.0 0.0003 21.31369
29.10 11.60 0.0 0.000198 0.017 225.0 0.0003 22.11543
29.60 10.60 0.0 0.000197 0.017 225.0 0.0003 22.67329
29.80 9.800 0.0 0.000197 0.017 225.0 0.0003 22.95817
29.90 9.500 0.0 0.000196 0.017 225.0 0.0003 23.08290
29.90 9.100 0.0 0.000196 0.017 225.0 0.0003 23.14401
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft)
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
(m)(concent) (m) (MGD) (psu)
4.0000 0.0
3.74E+6
300.00 0.0 0.0 16.000 13.000 48.800 200.00 23.940 5.3000
(C)(col/dl)
0.0 15.000
Simulation:
FroudeNo: 11.60; StratNo: 5.45E-4; Spcg No: 39.00; k:
1.790(m/s);
Depth Amb-cur
Step
(m)
(cm/s)
0
23.94
1.700
1
23.94
1.700
2
23.93
1.700
3
23.92
1.700
5
23.90
1.700
7
23.87
1.700
9
23.80
1.700
11
23.64
1.700
13
23.42
1.700
17
22.83
1.700
21
22.14
1.700
27
21.03
1.700
55
19.66
1.700
67
17.85
1.700
79
15.49
1.700
133
12.24
1.700
151
9.808
1.700
P-dia Polutnt net Dil x-posn
(in) (col/dl) () (m) (m)
105.3; eff den (sigmaT) -0.836341; eff vel
Iso dia
y-posn Time
(s) (m)
4.000 3.740E+6 1.000 0.0 0.0 0.0 0.1014; 11.44 T-90hr,
4.000 3.740E+6 1.000 0.0 0.0 0.0 0.1016; 11.44 T-90hr,
10.94 1.929E+6 1.939 -0.497 0.285 0.320
14.30 1.472E+6 2.540 -0.585 0.334 0.385
21.15 988111.0 3.785 -0.763 0.432 0.566
28.20 733621.0 5.098 -0.940 0.527 0.820
38.91 519516.6 7.199 -1.202 0.662 1.331
52.78 364415.9 10.26 -1.539 0.825 2.240
63.65 283591.1 13.19 -1.848 0.963 3.349
76.78 206140.1 18.14 -2.365 1.164 5.764
87.81 163240.4 22.91 -2.776 1.297 8.271
104.8 125663.6 29.76 -3.270 1.419 12.28
131.6 99789.2 37.48 -3.747 1.497 17.53
164.7 79160.1 47.25 -4.268 1.537 24.48
218.5 62651.8 59.70 -4.873 1.525 33.78
351.2 49337.1 75.81 -5.704 1.423 48.38
947.0 43327.2 86.32 -6.744 1.206 68.20
4/3 Power Law. Farfield dispersion based on wastefield width of 83.49 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
43327.2 86.32 83.51 6.851 2.78E-4 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
0.2780;
0.3632;
0.5372;
0.7162;
0.9883;
1.3405
1.6165
1.9498
2.2298
2.6616
11.43 T-90hr,
11.43 T-90hr,
11.42 T-90hr,
11.41 T-90hr,
11.38 T-90hr,
11.32 T-90hr,
merging; 11.24T-90hr,
11.01 T-90hr,
10.75 T-90hr,
10.33 T-90hr,
3.3416; 9.805 T-90hr,
4.1811; 9.113 T-90hr,
5.5450; 8.222 T-90hr,
8.9048; 7.033 T-90hr,
24.008; 6.180 T-90hr,
78
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
3.26E+6 98.22 125.2 48.80 0.686 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
2.14E+5 102.8 132.5 55.65 0.798 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
count: 1
August 5,2021
79
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 86.32
Estimated initial width (B) of plume after initial 83.49
dilution (meters)
Travel distance of plume after initial dilution 6.851
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
48.8
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
1.31E-
03
4. Horizontal current speed (m/sec)
0.017
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
4.33E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
1.0947E-01
9.2555E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
6.85E-01
41.949
48.80
9.65E+01
3.87E+04
97
80
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ uDKHLRD; for extra details examine output file \Plumes20\dkhwisp.out
Case 1; ambient file C:\Plumes20\Sitka C JullO.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg
0.0 0.017 225.0
1.000 0.017 225.0
5.000 0.017 225.0
10.00 0.017 225.0
15.00 0.017 225.0
20.00 0.017 225.0
25.00 0.017 225.0
30.00 0.017 225.0
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
psu C kg/kg s-1 m/s deg m0.67/s2 sigma-T
26.60 12.70 0.0 0.000196 0.017 225.0
26.60 12.70 0.0 0.000198 0.017 225.0
28.20 12.20 0.0 0.000198 0.017 225.0
29.10 11.60 0.0 0.000198 0.017 225.0
29.60 10.60 0.0 0.000197 0.017 225.0
29.80 9.800 0.0 0.000197 0.017 225.0
29.90 9.500 0.0 0.000196 0.017 225.0
29.90 9.100 0.0 0.000196 0.017 225.0
0.0003 19.98988
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
19.98988
21.31369
22.11543
22.67329
22.95817
23.08290
23.14401
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft)
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
(m)(concent) (m) (MGD) (psu)
4.0000 0.0 300.00
3.74E+6
0.0 0.0 16.000 13.000 122.00 200.00 23.940 5.3000
(C)(col/dl)
0.0 15.000
Simulation:
FroudeNo: 11.60; StratNo: 5.45E-4; Spcg No: 39.00; k: 105.3; eff den (sigmaT) -0.836341; eff vel
1.790(m/s);
Depth Amb-cur
Step
(m)
(cm/s)
0
23.94
1.700
1
23.94
1.700
2
23.93
1.700
3
23.92
1.700
5
23.90
1.700
7
23.87
1.700
9
23.80
1.700
11
23.64
1.700
13
23.42
1.700
17
22.83
1.700
21
22.14
1.700
27
21.03
1.700
55
19.66
1.700
67
17.85
1.700
79
15.49
1.700
133
12.24
1.700
151
9.808
1.700
P-dia Polutnt net Dil x-posn
(in) (col/dl) () (m) (m)
4.000 3.740E+6 1.000 0.0
4.000 3.740E+6 1.000 0.0
10.94 1.929E+6 1.939 -0.497
14.30 1.472E+6 2.540 -0.585
21.15 988111.0 3.785 -0.763
28.20 733621.0 5.098 -0.940
38.91 519516.6 7.199 -1.202
52.78 364415.9 10.26 -1.539
63.65 283591.1 13.19 -1.848
76.78 206140.1 18.14 -2.365
87.81 163240.4 22.91 -2.776
104.8 125663.6 29.76 -3.270
131.6 99789.2 37.48 -3.747
164.7 79160.1 47.25 -4.268
218.5 62651.8 59.70 -4.873
351.2 49337.1 75.81 -5.704
947.0 43327.2 86.32 -6.744
4/3 Power Law. Farfield dispersion based on wastefield width of 83.49 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
43327.2 86.32 83.51 6.851 2.78E-4 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
2.76E+6 138.1 183.2 100.0 1.522 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
y-posn
(s)
0.0
0.0
0.285
0.334
0.432
0.527
0.662
0.825
0.963
1.164
1.297
1.419
1.497
1.537
1.525
1.423
1.206
Time Iso dia
(m)
0.0 0.1014;
0.0 0.1016;
11.44 T-90hr,
11.44 T-90hr,
0.320
0.385
0.566
0.820
1.331
2.240
3.349
5.764
8.271
12.28
17.53
24.48
33.78
48.38
68.20
11.43 T-90hr,
11.43 T-90hr,
11.42 T-90hr,
11.41 T-90hr,
11.38 T-90hr,
11.32 T-90hr,
merging; 11.24T-90hr,
11.01 T-90hr,
10.75 T-90hr,
10.33 T-90hr,
9.805 T-90hr,
4.1811; 9.113 T-90hr,
5.5450; 8.222 T-90hr,
8.9048; 7.033 T-90hr,
24.008; 6.180 T-90hr,
0.2780;
0.3632;
0.5372;
0.7162;
0.9883;
1.3405
1.6165
1.9498
2.2298
2.6616
3.3416;
81
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
46877.1 236.4 315.8 200.0 3.156 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
23592.2 243.8 325.7 206.9 3.268 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
count: 2
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 86.32
Estimated initial width (B) of plume after initial 83.49
dilution (meters)
Travel distance of plume after initial dilution 6.851
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
122
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
1.31E-
03
4. Horizontal current speed (m/sec)
0.017
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
4.33E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
1.0947E-01
9.2555E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce(m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
1.88E+00
115.149
122.00
1.43E+02
2.61 E+04
143
82
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ uDKHLRD; for extra details examine output file \Plumes20\dkhwisp.out
Case 1; ambient file C:\Plumes20\Sitka C JullO.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg
0.0 0.017 225.0
1.000 0.017 225.0
5.000 0.017 225.0
10.00 0.017 225.0
15.00 0.017 225.0
20.00 0.017 225.0
25.00 0.017 225.0
30.00 0.017 225.0
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
psu C kg/kg s-1 m/s deg m0.67/s2 sigma-T
26.60 12.70 0.0 0.000196 0.017 225.0
26.60 12.70 0.0 0.000198 0.017 225.0
28.20 12.20 0.0 0.000198 0.017 225.0
29.10 11.60 0.0 0.000198 0.017 225.0
29.60 10.60 0.0 0.000197 0.017 225.0
29.80 9.800 0.0 0.000197 0.017 225.0
29.90 9.500 0.0 0.000196 0.017 225.0
29.90 9.100 0.0 0.000196 0.017 225.0
0.0003 19.98988
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
19.98988
21.31369
22.11543
22.67329
22.95817
23.08290
23.14401
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft)
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
(m)(concent) (m) (MGD) (psu)
4.0000 0.0 300.00
3.74E+6
0.0 0.0 16.000 13.000 244.00 200.00 23.940 5.3000
(C)(col/dl)
0.0 15.000
Simulation:
FroudeNo: 11.60; StratNo: 5.45E-4; Spcg No: 39.00; k: 105.3; eff den (sigmaT) -0.836341; eff vel
1.790(m/s);
Depth Amb-cur
Step
(m)
(cm/s)
0
23.94
1.700
1
23.94
1.700
2
23.93
1.700
3
23.92
1.700
5
23.90
1.700
7
23.87
1.700
9
23.80
1.700
11
23.64
1.700
13
23.42
1.700
17
22.83
1.700
21
22.14
1.700
27
21.03
1.700
55
19.66
1.700
67
17.85
1.700
79
15.49
1.700
133
12.24
1.700
151
9.808
1.700
P-dia Polutnt net Dil x-posn
(in) (col/dl) () (m) (m)
4.000 3.740E+6 1.000 0.0
4.000 3.740E+6 1.000 0.0
10.94 1.929E+6 1.939 -0.497
14.30 1.472E+6 2.540 -0.585
21.15 988111.0 3.785 -0.763
28.20 733621.0 5.098 -0.940
38.91 519516.6 7.199 -1.202
52.78 364415.9 10.26 -1.539
63.65 283591.1 13.19 -1.848
76.78 206140.1 18.14 -2.365
87.81 163240.4 22.91 -2.776
104.8 125663.6 29.76 -3.270
131.6 99789.2 37.48 -3.747
164.7 79160.1 47.25 -4.268
218.5 62651.8 59.70 -4.873
351.2 49337.1 75.81 -5.704
947.0 43327.2 86.32 -6.744
4/3 Power Law. Farfield dispersion based on wastefield width of 83.49 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
43327.2 86.32 83.51 6.851 2.78E-4 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
2.76E+6 138.1 183.2 100.0 1.522 0.0 8.000 1.700 225.0 3.00E-4 5.5441E-5
y-posn
(s)
0.0
0.0
0.285
0.334
0.432
0.527
0.662
0.825
0.963
1.164
1.297
1.419
1.497
1.537
1.525
1.423
1.206
Time Iso dia
(m)
0.0 0.1014;
0.0 0.1016;
11.44 T-90hr,
11.44 T-90hr,
0.320
0.385
0.566
0.820
1.331
2.240
3.349
5.764
8.271
12.28
17.53
24.48
33.78
48.38
68.20
11.43 T-90hr,
11.43 T-90hr,
11.42 T-90hr,
11.41 T-90hr,
11.38 T-90hr,
11.32 T-90hr,
merging; 11.24T-90hr,
11.01 T-90hr,
10.75 T-90hr,
10.33 T-90hr,
9.805 T-90hr,
4.1811; 9.113 T-90hr,
5.5450; 8.222 T-90hr,
8.9048; 7.033 T-90hr,
24.008; 6.180 T-90hr,
0.2780;
0.3632;
0.5372;
0.7162;
0.9883;
1.3405
1.6165
1.9498
2.2298
2.6616
3.3416;
83
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
46877.1 236.4 315.8 200.0 3.156 0.0 8.000 1.700
17411.5 352.0 470.5 300.0 4.790 0.0 8.000 1.700
13591.4 360.5 481.8 306.9 4.902 0.0 8.000 1.700
count: 3
225.0 3.00E-4 5.5441E-5
225.0 3.00E-4 5.5441E-5
225.0 3.00E-4 5.5441E-5
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 86.32
Estimated initial width (B) of plume after initial 83.49
dilution (meters)
Travel distance of plume after initial dilution 6.851
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
244
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
1.31E-
03
4. Horizontal current speed (m/sec)
0.017
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
4.33E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
1.0947E-01
9.2555E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce(m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
3.87E+00
237.149
244.00
2.27E+02
1.65E+04
227
84
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
Skagwav (model output for l*depth, 2*depth, 5*depth and 10*depth)
Contents of the memo box (may not be current and must be updated manually)
Project "C:\Plumes20\Skagway" memo
Model configuration items checked: Brooks far-field solution;
Channel width (m) 100
Start case for graphs 1
Max detailed graphs 10 (limits plots that can overflow memory)
Elevation Projection Plane (deg) 0
Shore vector (m,deg) not checked
Bacteria model : Mancini (1978) coliform model
PDS sfc. model heat transfer : Medium
Equation of State : S, T
Similarity Profile : Default profile (k=2.0, ...)
Diffuser port contraction coefficient 0.61
Light absorption coefficient 0.16
Farfield increment (m) 200
UM3 aspiration coefficient 0.1
Output file: text output tab
Output each ?? steps 100
Maximum dilution reported 100000
Text output format: Standard
Max vertical reversals : to max rise or fall
/ UM3. 6/23/2021 5:51:09 AM
Case 1; ambient file C:\Plumes20\Skagway_l_Jun05.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.014 350.0 7.100
I.523 0.014 350.0 14.16
3.047 0.014 350.0 23.30
4.570 0.014 350.0 23.25
6.090 0.014 350.0 25.20
7.617 0.014 350.0 26.37
9.140 0.014 350.0 26.74
10.45 0.014 350.0 27.46
II.75 0.014 350.0 28.24
13.06 0.014 350.0 28.92
14.37 0.014 350.0 29.08
15.68 0.014 350.0 29.29
16.98 0.014 350.0 30.42
20.00 0.014 350.0 33.05
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1
m/s
11.12 0.0 0.000194
10.08 0.0 0.000197
8.650 0.0 0.000197
8.670 0.0 0.000196
8.220 0.0 0.000196
8.020 0.0 0.000196
7.980 0.0 0.000195
7.570 0.0 0.000195
7.100 0.0 0.000195
6.920 0.0 0.000195
6.880 0.0 0.000195
6.790 0.0 0.000195
6.260 0.0 0.000195
5.029
0.0
0.0
0.0 0.000195
deg
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
m0.67/s2 sigma-
350.0 0.0003 5
0.0003
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
26.14924
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
85
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
(in) (deg) (deg) (m) (m)
3.0000 0.0 350.00 0.0 0.0
2.59E+6
() (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
5.0000 3.5000 18.300 200.00 18.150 0.6300 0.0 17.300
Simulation:
FroudeNo: 10.06; StratNo: 2.47E-3; Spcg No: 17.93;k: 88.59; eff den (sigmaT)-1.214163; eff vel
1.240(m/s);
Depth Amb-cur
Step
0
100
200
267
(m)
18.15
18.07
17.61
16.05
8.615 T-90hr.
300 15.34
318 15.20
T-90hr,
400 14.95
480 14.90
P-dia Polutnt
(cm/s) (in) (col/dl)
1.400 2.343 2.590E+6
1.400 12.32 471750.7
1.400 21.87 219905.3
1.400 42.65 85238.4
1.400 63.27 67833.1
1.400 71.39 65187.4
Dilutn x-posn
y-posn Time Iso dia
0 (m) (m) (s) (m)
I.000 0.0 0.0 0.0 0.0594; 9.458 T-90hr,
5.490 0.639 -0.113 1.673 0.3130; 9.424 T-90hr,
II.77 1.318 -0.232 6.056 0.5554; 9.240 T-90hr,
30.34 2.296 -0.405 19.44 1.0826; trap level, merging;
38.10 2.732 -0.482 28.58 1.6057; 8.339 T-90hr,
39.64 2.853 -0.503 31.31 1.8117; begin overlap; 8.285
1.400 94.95 62151.2 41.55 3.192 -0.563 39.26
1.400 102.6 61721.1 41.83 3.409 -0.601 44.43
fall; 8.170 T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.0000; CL(m): 3.4620
Lmz(m): 3.4620
forced entrain 1 14.06 3.247 2.606 1.000
Rate sec-1 0.00019534 dy-1 16.8772 kt: 0.000078146 Amb Sal 29.1654
4/3 Power Law. Farfield dispersion based on wastefield width of 10.07 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
2.4091; 8.187 T-90hr,
2.6036; local maximum rise or
(col/dl)
61721.1
55457.0
38485.5
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
41.83
59.02
66.05
10.08
19.36
21.80
3.462 2.78E-4
18.30
21.76
0.295
0.363
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
5:51:09 AM. amb fills: 4
86
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution
41.83
(e.g. dilution at end of computations with UDKHDEN)
Estimated initial width (B) of plume after initial
10.07
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
dilution (meters)
and plume diameter)
Travel distance of plume after initial dilution
3.462
(e.g. "Y" from UDKHDEN or horizontal distance from
(meters)
PLUMES output)
2. Distance from outfall to mixing zone boundary
18.3
(e.g. distance to the chronic mixing zone boundary)
(meters)
3. Diffusion parameter "alpha" per equations 7-62
6.48E-
of Grace, where Eo=(alpha)(width) m2/sec
04
4. Horizontal current speed (m/sec)
0.014
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay (these inputs do not affect calculated farfield dilution
(optional) factors)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
6.17E+
04
1.95E-
04
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.5237E-03
5.5529E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
2.94E-01
14.838
18.30
5.61 E+01
4.60E+04
56
boundary:
87
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
/ UM3. 6/23/2021 5:51:23 AM
Case 1; ambient file C:\Plumes20\Skagway_l_Jun05.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.014 350.0 7.100
I.523 0.014 350.0 14.16
3.047 0.014 350.0 23.30
4.570 0.014 350.0 23.25
6.090 0.014 350.0 25.20
7.617 0.014 350.0 26.37
9.140 0.014 350.0 26.74
10.45 0.014 350.0 27.46
II.75 0.014 350.0 28.24
13.06 0.014 350.0 28.92
14.37 0.014 350.0 29.08
15.68 0.014 350.0 29.29
16.98 0.014 350.0 30.42
20.00 0.014 350.0 33.05
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1 m/s
11.12 0.0 0.000194
10.08 0.0 0.000197
8.650 0.0 0.000197
8.670 0.0 0.000196
8.220 0.0 0.000196
8.020 0.0 0.000196
7.980 0.0 0.000196
7.570 0.0 0.000195
7.100 0.0 0.000195
6.920 0.0 0.000195
6.880 0.0 0.000195
6.790 0.0 0.000195
6.260 0.0 0.000195
5.029 0.0 0.000195
deg
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
m0.67/s2 sigma-
350.0 0.0003 5
0.0003
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
26.14924
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft)
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
(m)(concent) (m)
3.0000 0.0
2.59E+6
350.00 0.0 0.0 8.0000 3.5000 36.600 200.00
(MGD) (psu)
18.150 0.6300
(C)(col/dl)
0.0 17.300
Simulation:
FroudeNo: 10.06; StratNo: 2.47E-3; Spcg No: 17.93;k: 88.59; eff den (sigmaT) -1.214163; eff vel
1.240(m/s);
Depth Amb-cur
Step
0
100
200
267
(m)
18.15
18.07
17.61
16.05
8.615 T-90hr.
300 15.34
318 15.20
T-90hr,
400 14.95
480 14.90
(cm/s)
1.400
1.400
1.400
1.400
1.400
1.400
P-dia Polutnt
(in) (col/dl)
2.343 2.590E+6
12.32 471750.7
21.87 219905.3
42.65 85238.4
Dilutn x-posn
0 (m)
I.000
5.490
II.77
30.34
63.27
71.39
67833.1
65187.4
38.10
39.64
(m)
0.0
0.639
1.318
2.296
2.732
2.853
1.400 94.95 62151.2 41.55 3.192
1.400 102.6 61721.1 41.83 3.409
fall; 8.170 T-90hr,
Horiz plane projections in effluent direction: radius(m):
Lmz(m): 3.4620
y-posn
(s)
0.0 0
-0.113
-0.232
-0.405
-0.482
-0.503
-0.563
-0.601
Time Iso dia
(m)
.0 0.05945; 9.458 T-90hr,
1.673 0.3130; 9.424 T-90hr,
6.056 0.5554; 9.240 T-90hr,
19.44 1.0826; trap level, merging;
28.58 1.6057; 8.339 T-90hr,
31.31 1.8117; begin overlap; 8.285
39.26 2.4091; 8.187 T-90hr,
44.43 2.6036; local maximum rise or
0.0000; CL(m): 3.4620
88
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
forced entrain 1 14.06 3.247 2.606 1.000
Rate sec-1 0.00019534 dy-1 16.8772 kt: 0.000078146 Amb Sal 29.1654
4/3 Power Law. Farfield dispersion based on wastefield width of 10.07 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
61721.1
50071.9
23499.3
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
41.83 10.08 3.462 2.78E-4 0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
100.1 33.29 36.60 0.658 0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
108.8 36.19 40.06 0.726 0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
5:51:23 AM. amb fills: 4
89
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 41.83
Estimated initial width (B) of plume after initial 10.07
dilution (meters)
Travel distance of plume after initial dilution 3.462
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
36.6
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.48E-
04
4. Horizontal current speed (m/sec)
0.014
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
6.17E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.5237E-03
5.5529E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
6.58E-01
33.138
36.60
8.58E+01
3.01 E+04
86
90
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 6/23/2021 5:51:35 AM
Case 1; ambient file C:\Plumes20\Skagway_l_Jun05.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.014 350.0 7.100
I.523 0.014 350.0 14.16
3.047 0.014 350.0 23.30
4.570 0.014 350.0 23.25
6.090 0.014 350.0 25.20
7.617 0.014 350.0 26.37
9.140 0.014 350.0 26.74
10.45 0.014 350.0 27.46
II.75 0.014 350.0 28.24
13.06 0.014 350.0 28.92
14.37 0.014 350.0 29.08
15.68 0.014 350.0 29.29
16.98 0.014 350.0 30.42
20.00 0.014 350.0 33.05
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1
m/s
11.12
10.08
8.650
8.670
8.220
8.020
7.980
7.570
7.100
6.920
6.880
6.790
6.260
5.029
0.0 0.000194
0.0 0.000197
0.0 0.000197
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
deg
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
m0.67/s2 sigma-
350.0 0.0003 5
0.0003
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
26.14924
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft)
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
(m) (concent) (m)
3.0000 0.0 350.00
2.59E+6
0.0 0.0 8.0000 3.5000 91.500 200.00
(MGD) (psu)
18.150 0.6300
(C)(col/dl)
0.0 17.300
Simulation:
FroudeNo: 10.06; StratNo: 2.47E-3; Spcg No: 17.93;k: 88.59; eff den (sigmaT) -1.214163; eff vel
1.240(m/s);
Depth Amb-cur P-dia Polutnt Dilutn x-posn
Step
0
100
200
267
(m)
18.15
18.07
17.61
16.05
8.615 T-90hr.
300 15.34
318 15.20
T-90hr,
400 14.95
480 14.90
P-dia Polutnt
(cm/s) (in) (col/dl) () (m) (m)
1.400 2.343 2.590E+6 1.000 0.0
1.400 12.32 471750.7 5.490 0.639
1.400 21.87 219905.3 11.77 1.318
1.400 42.65 85238.4 30.34 2.296
1.400 63.27 67833.1 38.10 2.732
1.400 71.39 65187.4 39.64 2.853
y-posn
(s)
0.0
-0.113
-0.232
-0.405
-0.482
-0.503
Iso dia
Time
(m)
0.0 0.05945;
9.458 T-90hr,
1.673 0.3130; 9.424 T-90hr,
6.056 0.5554; 9.240 T-90hr,
19.44 1.0826; trap level, merging;
28.58 1.6057; 8.339 T-90hr,
31.31 1.8117; begin overlap; 8.285
1.400 94.95 62151.2 41.55 3.192 -0.563 39.26
1.400 102.6 61721.1 41.83 3.409 -0.601 44.43
fall; 8.170 T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.0000; CL(m): 3.4620
Lmz(m): 3.4620
forced entrain 1 14.06 3.247 2.606 1.000
Rate sec-1 0.00019534 dy-1 16.8772 kt: 0.000078146 Amb Sal 29.1654
4/3 Power Law. Farfield dispersion based on wastefield width of 10.07 m
2.4091; 8.187 T-90hr,
2.6036; local maximum rise or
91
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
cone dilutn
(col/dl)
61721.1
36855.9
9323.75
count: 1
width distnee time bckgrnd decay current cur-dir eddydif
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
41.83
263.9
275.8
10.08
87.83
91.82
3.462 2.78E-4
91.50
94.96
1.747
1.816
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
5:51:35 AM. amb fills: 4
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 41.83
Estimated initial width (B) of plume after initial 10.07
dilution (meters)
Travel distance of plume after initial dilution 3.462
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
91.5
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.48E-
04
4. Horizontal current speed (m/sec)
0.014
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day-1)
6.17E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.5237E-03
5.5529E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
1.75E+00
88.038
91.50
1.77E+02
1.46E+04
178
92
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 6/23/2021 5:51:47 AM
Case 1; ambient file C:\Plumes20\Skagway_l_Jun05.005.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur
Density
m m/s deg psu
0.0 0.014 350.0 7.100
I.523 0.014 350.0 14.16
3.047 0.014 350.0 23.30
4.570 0.014 350.0 23.25
6.090 0.014 350.0 25.20
7.617 0.014 350.0 26.37
9.140 0.014 350.0 26.74
10.45 0.014 350.0 27.46
II.75 0.014 350.0 28.24
13.06 0.014 350.0 28.92
14.37 0.014 350.0 29.08
15.68 0.014 350.0 29.29
16.98 0.014 350.0 30.42
20.00 0.014 350.0 33.05
Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
C kg/kg s-1
m/s
11.12
10.08
8.650
8.670
8.220
8.020
7.980
7.570
7.100
6.920
6.880
6.790
6.260
5.029
0.0 0.000194
0.0 0.000197
0.0 0.000197
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000196
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
0.0 0.000195
deg
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
0.014
m0.67/s2 sigma-
350.0 0.0003 5
0.0003
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
350.0
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.180276
10.78304
18.06627
18.02474
19.60292
20.54204
20.83621
21.45192
22.12180
22.67724
22.80770
22.98359
23.93584
26.14924
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft)
Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
(m)(concent) (m)
3.0000 0.0 350.00
2.59E+6
0.0 0.0 8.0000 3.5000 183.00 200.00
(MGD) (psu)
18.150 0.6300
(C)(col/dl)
0.0 17.300
Simulation:
FroudeNo: 10.06; StratNo: 2.47E-3; Spcg No: 17.93;k: 88.59; eff den (sigmaT) -1.214163; eff vel
1.240(m/s);
Depth Amb-cur P-dia Polutnt Dilutn x-posn
Step
0
100
200
267
P-dia Polutnt
(m) (cm/s) (in) (col/dl)
18.15 1.400 2.343 2.590E+6
1.400 12.32 471750.7
1.400 21.87 219905.3
1.400 42.65 85238.4
18.07
17.61
16.05
8.615 T-90hr,
300 15.34
318 15.20
T-90hr,
400 14.95
480 14.90
1.400
1.400
63.27
71.39
67833.1
65187.4
0 (m)
I.000
5.490
II.77
30.34
38.10
39.64
(m)
0.0
0.639
1.318
2.296
2.732
2.853
y-posn
(s)
0.0
-0.113
-0.232
-0.405
-0.482
-0.503
Iso dia
Time
(m)
0.0 0.05945;
9.458 T-90hr,
1.673 0.3130; 9.424 T-90hr,
6.056 0.5554; 9.240 T-90hr,
19.44 1.0826; trap level, merging;
28.58 1.6057; 8.339 T-90hr,
31.31 1.8117; begin overlap; 8.285
1.400 94.95 62151.2 41.55 3.192 -0.563 39.26
1.400 102.6 61721.1 41.83 3.409 -0.601 44.43
fall; 8.170 T-90hr,
Horiz plane projections in effluent direction: radius(m): 0.0000; CL(m): 3.4620
Lmz(m): 3.4620
forced entrain 1 14.06 3.247 2.606 1.000
Rate sec-1 0.00019534 dy-1 16.8772 kt: 0.000078146 Amb Sal 29.1654
4/3 Power Law. Farfield dispersion based on wastefield width of 10.07 m
2.4091; 8.187 T-90hr,
2.6036; local maximum rise or
93
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
cone dilutn
(col/dl)
61721.1
22115.3
3965.60
count: 1
width distnee time bckgrnd decay current cur-dir eddydif
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
41.83
634.0
649.9
10.08
211.0
216.3
3.462 2.78E-4
183.0
186.5
3.563
3.631
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
0.0 16.30 1.400 350.0 3.00E-4 7.8146E-5
5:51:47 AM. amb fills: 4
Brook's Linear
Diffusivity
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the linear diffusivity Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This sheet differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm. The
initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width).
INPUT
Linear Eddy
Diffusivity
Eo=(alpha)(width)
(Grace/Brooks equation 7-
65)
1. Plume and diffuser characteristics at start of far-field mixing
Flux-average dilution factor after initial dilution 41.83
Estimated initial width (B) of plume after initial 10.07
dilution (meters)
Travel distance of plume after initial dilution 3.462
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
2. Distance from outfall to mixing zone boundary
(meters)
183
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width) m2/sec
6.48E-
04
4. Horizontal current speed (m/sec)
0.014
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day-1)
6.17E+
04
1.95E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
6.5237E-03
5.5529E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
3.56E+00
179.538
183.00
3.30E+02
7.82E+03
331
94
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
Wrangell (model output for l*depth, 2*depth, 5*depth and 10*depth)
Contents of the memo box (may not be current and must be updated manually)
Project "C:\Plumes20\Wrangell" memoQ=
Model configuration items checked: Brooks far-field solution; Report effective dilution;
Channel width (m) 100
Start case for graphs 1
Max detailed graphs 10 (limits plots that can overflow memory)
Elevation Projection Plane (deg) 0
Shore vector (m,deg) not checked
Bacteria model : Mancini (1978) coliform model
PDS sfc. model heat transfer : Medium
Equation of State : S, T
Similarity Profile : Default profile (k=2.0, ...)
Diffuser port contraction coefficient 0.61
Light absorption coefficient 0.16
Farfield increment (m) 200
UM3 aspiration coefficient 0.1
Output file: text output tab
Output each ?? steps 100
Maximum dilution reported 100000
Text output format: Standard
Max vertical reversals : to max rise or fall
/ UM3. 8/3/2021 9:23:16 AM
Case 1; ambient file C:\Plumes20\Wrangell_4_Augl6.004.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur Amb
Density
m m/s deg
0.0 0.040 90.00
3.000 0.040 90.00
6.000 0.040 90.00
9.000 0.040 90.00
12.00 0.040 90.00
15.00 0.040 90.00
18.00 0.040 90.00
21.00 0.040 90.00
24.00 0.040 90.00
27.00 0.040 90.00
30.00 0.040 90.00
31.00 0.040 90.00
-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
psu C kg/kg s-1 m/s deg
11.00 11.30 0.0 0.000194 0.040
11.00 11.30 0.0 0.000194 0.040
11.20 12.70 0.0 0.000194 0.040
12.10 12.80 0.0 0.000194 0.040
12.80 11.90 0.0 0.000194 0.040
14.00 11.10 0.0 0.000194 0.040
14.90 11.10 0.0 0.000194 0.040
15.80 11.20 0.0 0.000194 0.040
16.20 11.00 0.0 0.000194 0.040
16.80 11.00 0.0 0.000194 0.040
16.90 10.90 0.0 0.000194 0.040
16.93 10.87 0.0 0.000194 0.040
m0.67/s2 sigma-
90.00 0.0003 8
0.0003
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
90.00
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
0.0003
T
.178952
8.178952
8.137535
8.815796
9.487716
10.52628
11.22223
11.90396
12.24129
12.70520
12.79661
12.82707
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
95
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
3.9500 0.0 90.000
1.91E+5
0.0 0.0 8.0000 32.000 30.500 200.00 30.350 3.0000 0.0 18.400
Simulation:
Froude No:
3.407(m/s);
32.56; StratNo: 8.40E-4; Spcg No: 124.5; k: 85.17; eff den (sigmaT) -1.415928; eff vel
Depth Amb-cur
P-dia Polutnt netDil x-posn
y-posn
Time
Iso dia
Step
(m)
(cm/s)
(in) (col/dl)
0 (m)
(m)
(s)
(m)
0
30.35
4.000
3.085 191000.0
1.000
0.0
0.0
0.0 0.0; 14.06 T-90hr,
100
30.32
4.000
21.88
25869.1
7.383
0.000
1.223
1.461
0.5546; 14.05 T-90hr,
200
29.23
4.000
75.55
6306.8
30.29
0.000
5.127
18.85
1.9038; 13.64 T-90hr,
265
25.85
4.000
147.1
2462.3
77.57
0.000
9.228
57.16
3.6599; trap level; 12.34 T-
90hr,
300
24.85
4.000
191.4
1914.4
99.77
0.000
10.45
72.89
4.7344; 11.95 T-90hr,
301
24.84
4.000
192.3
1907.0
100.2
0.000
10.47
73.16
4.7551; begin overlap; 11.95 T-
90hr,
400
24.32
4.000
227.5
1702.3
112.2
0.000
11.88
93.03
5.6075; 11.75 T-90hr,
415
24.32
4.000
228.3
1697.3
112.5
0.000
12.05
95.47
5.6269; local maximum rise or
fall;
11.75 T-90hr,
Horiz plane projections in effluent direction: radius(m):
0.0;
CL(m):
12.046
Lmz(m): 12.046
forced entrain 1 143.3 6.034 5.800 1.000
Rate sec-1 0.00019572 dy-1 16.9100 kt: 0.000054521 Amb Sal 16.2632
Plumes not merged, Brooks method may be overly conservative.
4/3 Power Law. Farfield dispersion based on wastefield width of 74.08 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl)
1697.28
1632.35
1668.65
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
112.0
112.0
112.4
74.09
81.17
85.91
12.05 2.78E-4
30.50
42.55
0.128
0.212
0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
9:23:18 AM. amb fills: 4
96
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
The initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width)4/3.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 112
Estimated initial width (B) of plume after initial 74.08
dilution (meters)
Travel distance of plume after initial dilution 12.05
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
30.5
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.04
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day-1)
1.70E+
03
1.96E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
9.3337E-02
3.7799E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
0.128125
18.45
30.5
1.12E+02
1697
113
97
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 8/3/2021 9:24:14 AM
Case 1; ambient file C:\Plumes20\Wrangell_4_Augl6.004.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m
m/s
deg
psu
C kg/kg
s-1 m/s
deg m0.67/s2 sigma-
-T
0.0
0.040
90.00
11.00
11.30
0.0 0.000195
0.040
90.00
0.0003 8
1.178952
3.000
0.040
90.00
11.00
11.30
0.0
0.000196
0.040
90.00
0.0003
8.178952
6.000
0.040
90.00
11.20
12.70
0.0
0.000196
0.040
90.00
0.0003
8.137535
9.000
0.040
90.00
12.10
12.80
0.0
0.000196
0.040
90.00
0.0003
8.815796
12.00
0.040
90.00
12.80
11.90
0.0
0.000196
0.040
90.00
0.0003
9.487716
15.00
0.040
90.00
14.00
11.10
0.0
0.000196
0.040
90.00
0.0003
10.52628
18.00
0.040
90.00
14.90
11.10
0.0
0.000196
0.040
90.00
0.0003
11.22223
21.00
0.040
90.00
15.80
11.20
0.0
0.000196
0.040
90.00
0.0003
11.90396
24.00
0.040
90.00
16.20
11.00
0.0
0.000196
0.040
90.00
0.0003
12.24129
27.00
0.040
90.00
16.80
11.00
0.0
0.000196
0.040
90.00
0.0003
12.70520
30.00
0.040
90.00
16.90
10.90
0.0
0.000196
0.040
90.00
0.0003
12.79661
31.00
0.040
90.00
16.93
10.87
0.0
0.000196
0.040
90.00
0.0003
12.82707
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.9500 0.0 90.000 0.0 0.0 8.0000 32.000 61.000 200.00 30.350 3.0000 0.0 18.400
1.91E+5
Simulation:
FroudeNo: 32.56; StratNo: 8.40E-4; Spcg No: 124.5;k: 85.17; eff den (sigmaT) -1.415928; eff vel
3.407(m/s);
Depth Amb-cur
P-dia Polutnt net Dil x-posn
y-posn
Time
Iso dia
Step
(m)
(cm/s)
(in) (col/dl)
0 (m)
(m)
(s)
(m)
0
30.35
4.000
3.085 191000.0
1.000
0.0
0.0
0.0 0.07603; 14.06 T-90hr,
100
30.32
4.000
21.88
25869.1
7.383
0.000
1.223
1.461
0.5546; 14.05 T-90hr,
200
29.23
4.000
75.55
6306.8
30.29
0.000
5.127
18.85
1.9038; 13.64 T-90hr,
265
25.85
4.000
147.1
2462.3
77.57
0.000
9.228
57.16
3.6599; trap level; 12.34 T-
90hr,
300
24.85
4.000
191.4
1914.4
99.77
0.000
10.45
72.89
4.7344; 11.95 T-90hr,
301
24.84
4.000
192.3
1907.0
100.2
0.000
10.47
73.16
4.7551; begin overlap; 11.95 T-
90hr,
400
24.32
4.000
227.5
1702.3
112.2
0.000
11.88
93.03
5.6075; 11.75 T-90hr,
415
24.32
4.000
228.3
1697.3
112.5
0.000
12.05
95.47
5.6269; local maximum rise or
fall;
11.75 T-90hr,
Horiz plane projections in effluent direction: radius(m):
0.0;
CL(m):
12.046
Lmz(m): 12.046
forced entrain 1 143.3 6.034 5.800 1.000
Rate sec-1 0.00019572 dy-1 16.9100 kt: 0.000054521 Amb Sal 16.2632
Plumes not merged, Brooks method may be overly conservative.
4/3 Power Law. Farfield dispersion based on wastefield width of 74.08 m
98
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs August 5,2021
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
(col/dl) (m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
1697.28 112.0 74.09 12.05 2.78E-4 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
1565.88 114.7 93.35 61.00 0.340 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
1596.09 117.5 98.31 73.05 0.424 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
count: 1
9:24:14 AM. amb fills: 4
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
The initial diffusion coefficient (Eo in m2/sec) is calculated as Eo = (alpha)(width)4/3.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 112
Estimated initial width (B) of plume after initial 74.08
dilution (meters)
Travel distance of plume after initial dilution 12.05
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
61
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.04
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day-1)
1.70E+
03
1.96E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
9.3337E-02
3.7799E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
0.339930
556
48.95
61
1.15E+02
1657
115
99
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 8/3/2021 9:24:33 AM
Case 1; ambient file C:\Plumes20\Wrangell_4_Augl6.004.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m
m/s
deg
psu
C kg/kg
s-1 m/s
deg m0.67/s2 sigma-
-T
0.0
0.040
90.00
11.00
11.30
0.0 0.000195
0.040
90.00
0.0003 8
1.178952
3.000
0.040
90.00
11.00
11.30
0.0
0.000196
0.040
90.00
0.0003
8.178952
6.000
0.040
90.00
11.20
12.70
0.0
0.000196
0.040
90.00
0.0003
8.137535
9.000
0.040
90.00
12.10
12.80
0.0
0.000196
0.040
90.00
0.0003
8.815796
12.00
0.040
90.00
12.80
11.90
0.0
0.000196
0.040
90.00
0.0003
9.487716
15.00
0.040
90.00
14.00
11.10
0.0
0.000196
0.040
90.00
0.0003
10.52628
18.00
0.040
90.00
14.90
11.10
0.0
0.000196
0.040
90.00
0.0003
11.22223
21.00
0.040
90.00
15.80
11.20
0.0
0.000196
0.040
90.00
0.0003
11.90396
24.00
0.040
90.00
16.20
11.00
0.0
0.000196
0.040
90.00
0.0003
12.24129
27.00
0.040
90.00
16.80
11.00
0.0
0.000196
0.040
90.00
0.0003
12.70520
30.00
0.040
90.00
16.90
10.90
0.0
0.000196
0.040
90.00
0.0003
12.79661
31.00
0.040
90.00
16.93
10.87
0.0
0.000196
0.040
90.00
0.0003
12.82707
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.9500 0.0 90.000 0.0 0.0 8.0000 32.000 152.50 200.00 30.350 3.0000 0.0 18.400
1.91E+5
Simulation:
FroudeNo: 32.56; StratNo: 8.40E-4; Spcg No: 124.5;k: 85.17; eff den (sigmaT) -1.415928; eff vel
3.407(m/s);
Depth Amb-cur
P-dia Polutnt net Dil x-posn
y-posn
Time
Iso dia
Step
(m)
(cm/s)
(in) (col/dl)
0 (m)
(m)
(s)
(m)
0
30.35
4.000
3.085 191000.0
1.000
0.0
0.0
0.0 0.07603; 14.06 T-90hr,
100
30.32
4.000
21.88
25869.1
7.383
0.000
1.223
1.461
0.5546; 14.05 T-90hr,
200
29.23
4.000
75.55
6306.8
30.29
0.000
5.127
18.85
1.9038; 13.64 T-90hr,
265
25.85
4.000
147.1
2462.3
77.57
0.000
9.228
57.16
3.6599; trap level; 12.34 T-
90hr,
300
24.85
4.000
191.4
1914.4
99.77
0.000
10.45
72.89
4.7344; 11.95 T-90hr,
301
24.84
4.000
192.3
1907.0
100.2
0.000
10.47
73.16
4.7551; begin overlap; 11.95 T-
90hr,
400
24.32
4.000
227.5
1702.3
112.2
0.000
11.88
93.03
5.6075; 11.75 T-90hr,
415
24.32
4.000
228.3
1697.3
112.5
0.000
12.05
95.47
5.6269; local maximum rise or
fall;
11.75 T-90hr,
Horiz plane projections in effluent direction: radius(m):
0.0;
CL(m):
12.046
Lmz(m): 12.046
forced entrain 1 143.3 6.034 5.800 1.000
Rate sec-1 0.00019572 dy-1 16.9100 kt: 0.000054521 Amb Sal 16.2632
Plumes not merged, Brooks method may be overly conservative.
4/3 Power Law. Farfield dispersion based on wastefield width of 74.08 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
100
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
(col/dl)
1697.28 112.0 74.09
1382.28 148.5 133.1
1220.33 154.2 138.7
count: 1
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
12.05 2.78E-4 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
152.5 0.976 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
164.5 1.059 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
9:24:33 AM. amb fills: 4
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 112
Estimated initial width (B) of plume after initial 74.08
dilution (meters)
Travel distance of plume after initial dilution 12.05
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
152.5
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.04
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day1)
1.70E+
03
1.96E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
9.3337E-02
3 7799E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e (m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
0.975347
ooo
zzz
140.45
152.5
1.49E+02
1280
149
101
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
/ UM3. 8/3/2021 9:24:50 AM
Case 1; ambient file C:\Plumes20\Wrangell_4_Augl6.004.db; Diffuser table record 2:
Ambient Table:
Depth Amb-cur Amb-dir Amb-sal Amb-tem Amb-pol Solar rad Far-spd Far-dir Disprsn
Density
m
m/s
deg
psu
C kg/kg
s-1 m/s
deg m0.67/s2 sigma-
-T
0.0
0.040
90.00
11.00
11.30
0.0 0.000195
0.040
90.00
0.0003 8
1.178952
3.000
0.040
90.00
11.00
11.30
0.0
0.000196
0.040
90.00
0.0003
8.178952
6.000
0.040
90.00
11.20
12.70
0.0
0.000196
0.040
90.00
0.0003
8.137535
9.000
0.040
90.00
12.10
12.80
0.0
0.000196
0.040
90.00
0.0003
8.815796
12.00
0.040
90.00
12.80
11.90
0.0
0.000196
0.040
90.00
0.0003
9.487716
15.00
0.040
90.00
14.00
11.10
0.0
0.000196
0.040
90.00
0.0003
10.52628
18.00
0.040
90.00
14.90
11.10
0.0
0.000196
0.040
90.00
0.0003
11.22223
21.00
0.040
90.00
15.80
11.20
0.0
0.000196
0.040
90.00
0.0003
11.90396
24.00
0.040
90.00
16.20
11.00
0.0
0.000196
0.040
90.00
0.0003
12.24129
27.00
0.040
90.00
16.80
11.00
0.0
0.000196
0.040
90.00
0.0003
12.70520
30.00
0.040
90.00
16.90
10.90
0.0
0.000196
0.040
90.00
0.0003
12.79661
31.00
0.040
90.00
16.93
10.87
0.0
0.000196
0.040
90.00
0.0003
12.82707
Diffuser table:
P-dia VertAng H-Angle SourceX SourceY Ports Spacing MZ-dis Isoplth P-depth Ttl-flo Eff-sal
Temp Polutnt
(in) (deg) (deg) (m) (m) () (ft) (m)(concent) (m) (MGD) (psu) (C)(col/dl)
3.9500 0.0 90.000 0.0 0.0 8.0000 32.000 305.00 200.00 30.350 3.0000 0.0 18.400
1.91E+5
Simulation:
FroudeNo: 32.56; StratNo: 8.40E-4; Spcg No: 124.5;k: 85.17; eff den (sigmaT) -1.415928; eff vel
3.407(m/s);
Depth Amb-cur
P-dia Polutnt net Dil x-posn
y-posn
Time
Iso dia
Step
(m)
(cm/s)
(in) (col/dl)
0 (m)
(m)
(s)
(m)
0
30.35
4.000
3.085 191000.0
1.000
0.0
0.0
0.0 0.07603; 14.06 T-90hr,
100
30.32
4.000
21.88
25869.1
7.383
0.000
1.223
1.461
0.5546; 14.05 T-90hr,
200
29.23
4.000
75.55
6306.8
30.29
0.000
5.127
18.85
1.9038; 13.64 T-90hr,
265
25.85
4.000
147.1
2462.3
77.57
0.000
9.228
57.16
3.6599; trap level; 12.34 T-
90hr,
300
24.85
4.000
191.4
1914.4
99.77
0.000
10.45
72.89
4.7344; 11.95 T-90hr,
301
24.84
4.000
192.3
1907.0
100.2
0.000
10.47
73.16
4.7551; begin overlap; 11.95 T-
90hr,
400
24.32
4.000
227.5
1702.3
112.2
0.000
11.88
93.03
5.6075; 11.75 T-90hr,
415
24.32
4.000
228.3
1697.3
112.5
0.000
12.05
95.47
5.6269; local maximum rise or
fall;
11.75 T-90hr,
Horiz plane projections in effluent direction: radius(m):
0.0;
CL(m):
12.046
Lmz(m): 12.046
forced entrain 1 143.3 6.034 5.800 1.000
Rate sec-1 0.00019572 dy-1 16.9100 kt: 0.000054521 Amb Sal 16.2632
Plumes not merged, Brooks method may be overly conservative.
4/3 Power Law. Farfield dispersion based on wastefield width of 74.08 m
cone dilutn width distnee time bckgrnd decay current cur-dir eddydif
102
-------
Great Lakes Environmental Center, Inc (GLEC)
Mixing Zone Dilution Modeling for Six Alaska POTWs
August 5,2021
(col/dl)
1697.28
1295.62
819.357
642.616
count: 2
(m) (m) (hrs)(col/dl) (ly/hr) (cm/s) angle(m0.67/s2)
112.0
171.8
286.6
294.2
74.09
155.5
261.7
268.7
12.05 2.78E-4 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
200.0 1.306 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
400.0 2.694 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
412.0 2.778 0.0 16.34 4.000 90.00 3.00E-4 5.4521E-5
9:24:50 AM. amb fills: 4
Brook's four-third Power Law
FARFIELD.XLS: Far-field dilution of initially diluted effluent plumes using the 4/3 power law Brooks model as presented by
Grace (R.A. Grace. Marine outfall systems: planning, design, and construction. Prentice-Hall, Inc.)
This apporach differs from the PLUMES approach by assuming different units for alpha depending on the far-field algorithm.
INPUT
4/3 Power Law
Eo=(alpha)*(width)4/3
(Grace/Brooks equation 7-66)
1. Plume and diffuser characteristics at start of far-field
mixing
Flux-average dilution factor after initial dilution 112
Estimated initial width (B) of plume after initial 74.08
dilution (meters)
Travel distance of plume after initial dilution 12.05
(meters)
(e.g. dilution at end of computations with UDKHDEN)
(e.g. eqn 70 of EPA/600/R-94/086 for diffuser length
and plume diameter)
(e.g. "Y" from UDKHDEN or horizontal distance from
PLUMES output)
2. Distance from outfall to mixing zone boundary
(meters)
305
(e.g. distance to the chronic mixing zone boundary)
3. Diffusion parameter "alpha" per equations 7-62
of Grace, where Eo=(alpha)(width)4/3 m2/sec
0.0003
4. Horizontal current speed (m/sec)
0.04
(e.g. same value specified for UDKHDEN or
PLUMES)
5. Pollutant initial concentration and decay
(optional)
Pollutant concentration after initial dilution (any
units)
Pollutant first-order decay rate constant (day-1)
1.70E+
03
1.96E-
04
(these inputs do not affect calculated farfield dilution
factors)
(e.g. effluent volume fraction = 1/initial dilution)
(e.g. enter 0 for conservative pollutants)
OUTPUT
Eo =
Beta =
9.3337E-02
3.7799E-01
m2/s
unitless
Far-field
Travel
Time
(hours)
Far-field
Travel
Distanc
e(m)
Total
Travel
Distan
ce (m)
Effluent
Dilution
Pollutant
Concentration
Dilution at mixing zone
boundary:
2.034375
292.95
305
2.29E+02
829
230
103
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