Basal Water Initiatives Syncrude Aurora North Mine Basal Water

Basal Water Initiatives
Syncrude Aurora North Mine
Dallas Heisler P.Eng
Overview
Water at the Aurora North Mine
Basal Water Issue
Basal Water Solution
Results
Syncrude Aurora North Mine
Bounded by Two Oceans
Surficial Aquifer
Oilsand
Pond Muds
Basal Aquifer
Limestone
Bounded by Two Oceans
“Surficial Aquifer”
Surficial Aquifer
Dewatering
Oilsand
Basal Aquifer
Bounded by Two Oceans
“Basal Aquifer”
Overburden
Oilsand
Basal Aquifer
Bounded by Two Oceans
“Basal Aquifer”
Overburden
Oilsand
Basal Aquifer
Basal Aquifer Depressurization Wells
34
44
Results
48
30
45
37
49
35
43
33
50
22
32
26
15
41
31
52
x
38
25
10
51
53
39
40
01
08
13
Photo: June 2009
Basal Depressurization Well
Water Quality
TDS – 500 to 2100 mg/L
Cl – 25 to 650 mg/L
Ammonia – 1.2 to 2.2 mg/L
Sulphide – 0.5 to 6.3 mg/L
Water Quality Concerns
Sulphide
•
Potential H2S concern
Oxidation of Sulphide to Sulphate
•
Sulphate less concern
Basal Aeration Test
Water quality modeling
•
Golder Associates
Six month field test
Water Quality Modelling
Pond dimensions
Input volumes (Basal water)
Oxygen required for sulphide
oxadiation
Modelling
“Results”
Constraint was Sulphide
500m Pond
4700 m3/d Basal water
Oxygen 1071 kg/day
Chemistry would meet guideline
requirements?
Aeration Test Pond
0
100m
Aeration System
Air Compressor
HDPE pipe
Old surficial ditch
Aeration Pond Profile
Air Compressor
Air to Pipe
Water Level
Perforated Pipe
Bottom of Ditch
Water Quality
“Aeration Test”
TDS – 1120 mg/L
Cl – 110 mg/L
Ammonia – 1.4 mg/L
Sulphide – 4.0 mg/L
Water Quality
“Results”
TDS – 1080 mg/L
Cl – 100 mg/L
Ammonia – 0.25 mg/L
Sulphide – 0.005 mg/L
Challenges
Real estate
Mining advancement and
changes
Air compressor reliability
New Aeration System
Compact single well aeration
•
1.5m compared to 500m
Same principle as test system
5 micron air bubbles
Rapid reaction between oxygen and
water
Aeration
Results
48
34
44
30
45
37
49
35
43
33
50
22
26
52
x
38
10
51
40
01
08
13
Photo: June 2009
DP Well to Tailings
DP Well to the Environment
Acknowledgements
Warren Zubot
Grey Kampala
Bill Hunter
Ross Noble
Nathalie Berube
Questions ??