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69th SWCS International Annual Conference “Making Waves in Conservation: Our Life on Land and Its Impact on Water” July 27-30, 2014 Lombard, IL
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M0nitoring and Analysis of a Novel Highway Runoff Treatment System for Application in
Salt Vulnerable Areas
By: Bill Trenouth, M.Sc., EIT
1
And B. Gharabaghi, Ph.D., P.Eng.
Doctoral Candidate, Water Resources Engineering, University of GuelphM.A.Sc., Water Resource Engineering, University of Guelph (2011)
TSWCS ConferenceJuly 28th, 2014
Outline
Background Objectives Laboratory Testing Site Description Field Facility Preliminary Results Next Steps Acknowledgements
2
Some Context In May 2000, the contamination of a municipal water supply in Walkerton, Ontario led to an E.coli outbreak in which approximately 5,000 became ill and 7 people died
The Outcome The tragedy led to a Provincial Enquiry into the issue, and a number of recommendations were made. The Government of Ontario promised to not only protect municipal drinking water sources, but also to make Ontario’s drinking water the safest in the world
Highway Threat Assessment Between rain or melt events, pollutants tend to accumulate on road surfaces, including: Sediment Chromium Cadmium Copper Zinc Nickel Chlorides
5
Concentrations of these pollutants are a function of: Average annual daily traffic (AADT) Duration between wash off events (ADD)
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Quality of the vehicles on the road
Joo‐Hyon Kang et al., 2006
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5M tonnes of road salt applied annually in Canada (EC, 2007) 1.1M tonnes in Ontario alone (1998) Number is roughly double that in the U.S.
Private contractors tend to apply salt at a density that is 4X greater than public agencies Application excess is in response to liability issues Total contributionremains unquantified
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4.3 x
Guidelines
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The US EPA has set chronic and acute toxicity thresholds for chlorides which are 230 mg/L and 860 mg/L respectively (EPA, 1988)
More recently, the CCME (2011) has introduced its own guidelines for chlorides in surface waters:
Long-Term (Chronic) Exposure
Short-Term (Acute) Exposure
120 mg Cl-/L 640 mg Cl-/L
Regulations
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Aesthetic chloride ion concentration (taste) objectives for Ontario drinking water are 250 mg/L Cl‐ Exceedances of this have already been detected in
urban wellfields in the Waterloo area (Bester et al., 2006)
Implications Chemically‐induced meromixis Death of aquatic organisms Groundwater concentrations of Cl‐ in excess of 1,600mg/L found in Pickering Greatly exceeds Ontario drinking water guidelines Exceeds 96h LC50 for some amphibians
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Kilgour and Associates, 200912
Implications
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Our research group has collected streamside chloride ion concentrations in excess of 5,700 mg/L in urban areas
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
12/2
/201
0
12/2
2/20
10
1/11
/201
1
1/31
/201
1
2/20
/201
1
3/12
/201
1
Cl- C
once
ntra
tion
(mg/
L)
Chloride Ion Concentration (Gordon Rd; Winter 2010-2011)
Gordon Rd
Objective
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Room for Improvement?
Objectives
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Using bench‐scale tests, assess the adsorption capability of several media at removing common highway pollutants
Using continuous monitoring techniques, assess the performance of the installed field system at capturing, detaining and attenuating the movement of multiple pollutants
Assess the imperviousness and longevity of several liners under normal field conditions, and quantify their effectiveness at protecting groundwater
Screening & Laboratory Testing
Based on a review of the literature, multiple candidate materials were tested:
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Column and Shaker Tests
Laboratory shaker tests to screen candidate material Column and drip testing for successful materials
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Column Construction
Design based on research objectives and details available in the literature (e.g. Safadoust et al., 2011; Starrett et al., 1996)
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Sensor Calibration
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(S1) y = 596.93xR² = 0.999
(S2) y = 607.13xR² = 0.999
(S3) y = 599.1xR² = 0.999
0
5,000
10,000
15,000
20,000
25,000
0 5 10 15 20 25 30 35
NaC
l Con
cent
ratio
n (m
g/L)
Specific Conductivity (mS/cm)
Conductivity Sensor Calibration
S1
S2
S3
Linear (S1)
Linear (S2)
Linear (S3)
Valve Calibration
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y = 1.3581x0.51
R² = 0.991
y = 0.6902x0.46
R² = 0.998
y = 0.2073x0.45
R² = 0.997
0.00
0.50
1.00
1.50
2.00
2.50
0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25
Flow
(L/s
)
Head Pressure (m)
Ball Valve Rating Curves: Various Apertures (Multi-Stage)
132 Degress
145 Degrees
157 Degrees
Preliminary Results
Preliminary Results – Objective 1 The heavy metals removal results were
satisfactory for a number of the evaluated materials:
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0%
20%
40%
60%
80%
100%
BOF SLAG 30G IRON STOCKPILE 30G RED SAND 30G GOETHITE SOIL 30G
Rem
oval
Eff
icie
ncy
Sample
Heavy Metals Removal Results
Chromium (Cr)-Total Cobalt (Co)-Total Copper (Cu)-Total Lead (Pb)-Total Nickel (Ni)-Total Zinc (Zn)-Total
Preliminary Results – Objective 1
For chlorides:
24-5
0
5
10
15
20
25
30
35
5,000 4,000 3,000 2,000 1,000Perc
ent R
educ
tion
(%)
Salt Concentration (mg/L)
Comparison of Conductivity Reduction for Six Materials (48 Hour Test)
Comparison of Conductivity Reduction for Five Materials (48 Hour Test)
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0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
1 2 3 4 5 6 7 8 9 10
Chl
orid
e Io
n C
onc.
(m
g/L
)
Bottle #
Chloride Removal for Amendment 5
Initial Chloride Ion Conc.
Final Chloride Conc. (Pre-Filter)
Final Chloride Conc. (Post-Filter
Preliminary Results – Objective 1
Field Facility – Objective 2 Upscaling from the Laboratory to the Field Peak dampening from diffusion, storage & adsorption Testing of Various Liners Sub‐surface Leak Detection
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27
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www.guelphmtowaterquality.com
Melt Water Capture and Treatment
Storm Event Winter Event Precipitation Depth (mm)
Total Event Precipitation Volume (L)
Total Event Runoff Volume Intercepted by the
Liner System (L)Start Date End Date
31/Oct/13 3/Nov/13 11.4 27,360 34,3646/Nov/13 7/Nov/13 13.8 33,120 8,14320/Dec/14 22/Dec/14 45.3 108,720 15,60711/Jan/14 15/Jan/14 19.5 46,800 49,22331/Jan/14 31/Jan/14 0.0 - 9042/Feb/14 3/Feb/14 15.3 36,720 3,246
20/Feb/14 24/Feb/14 17.4 41,760 28,3787/Mar/14 15/Mar/14 6.6 15,840 88,659
18/Mar/14 22/Mar/14 1.6 3,840 27,99628/Mar/14 29/Mar/14 4.5 10,800 7,760
TOTAL 135.4 324,960 264,280
Compacted Clay allows for upwelling from seasonal water table
Water Quantity
0
0.4
0.8
1.2
1.6
2
1/10/2014 12:00 1/12/2014 0:00 1/13/2014 12:00 1/15/2014 0:00
Flow
(lps
)
Date and Time
Melt Model
Cumulative Underdrains
Water Quality – Objective 3
Next Steps
Initial results are promising, but further testing is required. This includes the data collected on heavy metals at the field site More information is needed about the elasticity of the system, as well as the adsorption/desorption parameters
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Acknowledgements
We would like to thank the following partners for their support:
Ontario Ministry of Transportation Filtrexx Canada
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Thank youBill Trenouth, Ph.D. Candidate, EITSchool of Engineering,University of [email protected]
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