DDYEYE TTRACERRACER SSTUDIESTUDIES
David McBride, PE and Bill Fox, PECosmopolitan Engineering Group
PNCWA ConferenceBend, Oregon
October 26, 2010
Tracer Study ObjectivesTracer Study Objectives
• Outfall inspections (Integrity/Function)
• Quantify dilution
• Quantify reflux
• Calibrate hydrodynamic model
• Calculate residual circulation/flushing time
• Measure dispersion coefficients
• Transport to critical areas
• Discharge measurement
Quantify Dilution Quantify Dilution –– OverviewOverview
• Tracers
• Equipment
• Injection
• Plume Measurement Methods
• Ancillary data
• Interpretation
Fluorescent TracersFluorescent Tracers
• What is a fluorescent substance?• The ideal tracer
– Water soluble– Strongly fluorescent– Unique spectrum– Stable– Harmless– Inexpensive
• Fluorescent tracers– Rhodamine WT - Pontacyl Pink– Rhodamine B - Chlorophyll– Fluorescein - Hydrocarbons
Rhodamine WTRhodamine WT
• Red, fluorescent dye
• Stable in the environment
• Non-toxic
• Highly visible
• Shipped in 24% solution (s.g. = 1.15)
• Approximately $25/lb
• Keystone Aniline (Compton, CA)
Rhodamine WTRhodamine WT
• Concentration comparison
Dye Concentration(ppb) Commentary
1.0 Low end of desired detection range10 Visible in clear reservoir
25-50 Calibration reference standard100 Near upper limit of linear range
10,000 Non-toxic to aquatic life238 million 23.8% stock solution Rhodamine WT
Rhodamine WTRhodamine WT
• Factors affecting fluorescence– Temperature
– Reactivity (Cl2, SO2, O2)
– Photochemical decay
– Sorption
– Concentration quenching
Equipment Equipment -- FluorometersFluorometers
• Turner Model 10-AU
• Lab Fluorometers
• Turner SCUFA
• Field Models
Fluorometer CalibrationFluorometer Calibration
• Dye Standards– Serial dilutions
– Blanking
• Techniques– Pre-calibration
– Field checks
– Post-calibration
Dye InjectionDye Injection
• Goal: Uniform concentration
• Pumping setup
• Target concentration (500-5,000 ppb)
• Dye monitoring
• Manhole sampling
Field Methods Field Methods –– Shallow StreamShallow Stream
• Wade• Ropes/range lines for positioning• Discrete samples to laboratory
Field Methods Field Methods –– Visible PlumeVisible Plume
• Submersible (SCUFA)
• Flow-through (Turner 10-AU)
• Position with ropes and anchors
• GPS recordings/rope stationing
• Link to CTD for depth
Field Methods Field Methods –– Submerged PlumeSubmerged Plume
• Boat
• Plume reconnaissance
• Position with ropes, anchors, GPS coordinates, CTD
• Density stratified?
• Use drogues
Acute Mixing Zone SamplingAcute Mixing Zone Sampling
• Problems:– finding the plume
– staying in the plume
– positional accuracy
– data interpretation
Quantify Reflux Quantify Reflux –– OverviewOverview
• Method 1: Superposition (Hubbard and Stamper, 1972)
• Method 2: Quasi-steady buildup(EPA, 1992)
• Method 3: Default (rd=0.5)
Reflux Method 2,Alternative 1Reflux Method 2,Alternative 1Mixing Zone Boundary StationMixing Zone Boundary Station
Hydrodynamic Model DevelopmentHydrodynamic Model Development
Station 49 Dye Concentrations
0
2
4
6
8
10
12
Tide
Lev
el (f
t)
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
Dye C
oncentration (ppb)
Tide (Marysville)Dye ConcentrationModel (ADFAC = 0.00)Corrected2 Period Moving Avg.
26-Aug 27-Aug 28-Aug 29-Aug 30-Aug
Hydrodynamic Model DevelopmentHydrodynamic Model Development
Station 56 Dye Concentrations
0
2
4
6
8
10
12
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Tide (Marysville)Dye ConcentrationModel (ADFAC = 0.00)2 Period Moving Avg.
26-Aug 27-Aug 28-Aug 29-Aug 30-Aug
Flushing TimeFlushing Time
Col
umbi
a R
iver
ISCO Station 1ISCO Station 1
Ridgefield WWTP Outfall
Ridgefield WWTP Outfall
City of RidgefieldCity of Ridgefield
ISCO Station 2ISCO Station 2
Lake RiverLake River
Columbia Slough
Columbia Slough
Flushing TimeFlushing Time
1st High 1st Low 2nd High 2nd Low
Lake River TransectsAugust 30-31, 2004
0.1
1
10
100
-5000 -2500 0 2500 5000 7500 10000
Distance Downstream of Outfall, ft
Dye
Con
cent
ratio
n,pp
b
Dispersion Coefficient Dispersion Coefficient –– TransverseTransverse
Upstream Mixing Zone Boundary8:50 - 3/4 Flood
0
1
2
3
4
5
6
7
8
9
60 70 80 90 100 110 120 130 140
Distance from Right Bank, ft
Dye
Con
cent
ratio
n, p
pb
1 ft 3 ft 5 ft Model
Centerline Profile8:45 - 3/4 Flood
0
1
2
3
4
5
0 2 4 6 8
Depth, ft
Dye
Con
cent
ratio
n, p
pb
Dispersion Coefficient Dispersion Coefficient –– TransverseTransverseUpstream Mixing Zone Boundary
High Slack
0
1
2
3
4
5
6
7
8
60 70 80 90 100 110 120 130 140
Distance from Right Bank, ft
Dye
Con
cent
ratio
n, p
pb
2 ft 2 ft 4 ft 4 ft Model
Dispersion Coefficient Dispersion Coefficient –– TransverseTransverseDownstream Mixing Zone Boundary
13:35 - Mid Ebb
0
1
2
3
4
5
6
7
8
9
10
60 70 80 90 100 110 120 130 140
Distance from Right Bank, ft
Dye
Con
cent
ratio
n, p
pb
5 ft 2 ft Model
Centerline Profile13:45 - Mid Ebb
0
2
4
6
8
10
0 2 4 6 8 10
Depth, ft
Dye
Con
cent
ratio
n, p
pb
Stationary Time Series14:00 - Mid Ebb
01234567
14:02:15 14:02:59 14:03:42 14:04:25
Dye
Con
cent
ratio
n, p
pb
3 sec 30 sec 60 sec
ReferencesReferencesTurner Designs Application Notes:
www.turnerdesigns.com/t2/doc/appnotes/tracer_dye.html
General:Kilpatrick, F.A., and E.D. Cobb, Measurement of Discharge Using Tracers, Chapter A16, Techniques of Water-
Resources Investigations of the USGS, Book 3, Application of Hydraulics, USGS, U.S. Department of the Interior,Reston, VA 1985.
Wilson, J.F., E.D. Cobb, and F.,A. Kilpatrick, Fluorometric Procedures for Dye Tracing, Chapter A12. Techniques of Water-Resources Investigations of the USGS, Book 3, Application of Hydraulics, USGS, U.S. Department of theInterior, Reston, VA 1986.
Reflux:
EPA, 1992. Technical Guidance Manual for Performing Waste Load Allocations Book III: Estuaries, Part 3: Use of Mixing Zone Models in Estuarine Waste Load Allocations, U.S. Environmental Protection Agency, EPA/823/R-092/004, section 2.6.
Hubbard, E.F. and W.G. Stamper, 1972. Movement and Dispersion of Soluble Pollutants in the Northeast Cape FearEstuary, North Carolina, Water-supply paper 1873-E, U.S. Geological Survey, United States Department of the Interior.
Chlorine Quenching:
Deaner, D.G. 1973. Effect of Chlorine on Fluorescent Dyes. Journal of Water Pollution Control Federation, V.45:3. 1973. p.507-514.
Turbidity and Adsorption:Ebbesmeyer, C., B. Fox, G. Cannon, M. Kawasi, B. Nairn. 2002. Puget Sound Physical Oceanography Related to the
Triple Junction Region, Brightwater Marine Outfall, Appendix G. Dye Studies. Submitted to King CountyDepartment of Natural Resources and Parks. November 2002.