HomeMy WebLinkAboutItm 3b_South Y PCE Jun 18 2019 TAC 5_DRIFinal Alternatives Modeling
Desert Research Institute
Susie Rybarski
Mark Hausner
TAC Meeting 5
South Y Feasibility Study of
Remedial Alternatives (D1712508-1)
6/21/19
PCE Model Recalibration
Changes from previous model versions
•Adjusted screened interval at LBWC 4
•Added expanded clay lens acting as low vertical conductivity zone
•Decreased longitudinal dispersivity to 40m
•Increased vertical dispersivity ratio to 0.015
•Increased transverse dispersivity ratio to 0.6 in layers 1 and 2
•Increased decay half-life to 17 years in layers 1 and 2
•Decreased source term by 30% during years LTLW is in operation
Calibration Results
0
50
100
150
200
250
1971 1977 1982 1988 1993 1999 2004 2010 2015
PC
E
(
u
g
/
l
)
Clement
Simulated Observed
0
50
100
150
200
250
300
1971 1977 1982 1988 1993 1999 2004 2010 2015
PC
E
(
u
g
/
l
)
Rockwater
Simulated Observed
0
50
100
150
200
250
1971 1977 1982 1988 1993 1999 2004 2010 2015
PC
E
(
u
g
/
l
)
LBWC 4
Simulated Observed
Calibration Results
0
10
20
30
40
50
60
70
80
1971 1977 1982 1988 1993 1999 2004 2010 2015
PC
E
(
u
g
/
l
)
LBWC 5
Simulated Observed
0
5
10
15
20
25
30
1971 1977 1982 1988 1993 1999 2004 2010 2015
PC
E
(
u
g
/
l
)
TKWC 2
Simulated Observed
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
1971 1977 1982 1988 1993 1999 2004 2010 2015
PC
E
(
u
g
/
l
)
TKWC 1
Simulated Observed
2018 stress period, layer 1 2018 stress period, layer 2
2018 stress period, layer 3 Scenario 1A clay lens, 2038 stress period, layer 2 2018 stress period, layer 4
Final Alternatives Modeling
Simulated Alternatives
Alternative Description Pumping Rates (m3/d)
LBWC 1 LBWC 5 TKWC 1 TKWC 2 TKWC 3 Sunset Paloma Helen 2 Bayview Al Tahoe 2
1A Baseline 872.19 199.66 532.54 1219.49 1316.98 1735.79 195.74 713.22 8997.45 1462.21
1B Conservative
Baseline** 872.19 199.66 532.54 1219.49 1316.98 1735.79 195.74 713.22 8997.45 1462.21
2A Targeted 199.66 872.19 532.54 1316.98 1219.49 1735.79 195.74 713.22 8997.45 1462.21
2B Conservative
Targeted** 199.66 872.19 532.54 1316.98 1219.49 1735.79 195.74 713.22 8997.45 1462.21
3A SW Conversion 872.19 199.66 532.54 1219.49 1316.98 1735.79 195.74 713.22 8997.45 1462.21
3B Conservative
SW Conversion** 872.19 199.66 532.54 1219.49 1316.98 1735.79 195.74 713.22 8997.45 1462.21
4 90% GAC Capacity 389.52 3434.13 1458.14 2698.24 808.56 1165.41 131.57 478.85 6039.43 981.75
5 90% Well Capacity 389.52 3434.13 1458.14 8830.61 808.56 353.01 39.85 145.05 1829.36 297.38
** Conservative simulations include a ‘constant bleed’ recharge concentration and no biogenic decay
Alternative 1A: Baseline
0
1
2
3
4
5
6
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 1
MCL
Detection Limit
0
2
4
6
8
10
12
14
16
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 2
MCL
Detection Limit
0
5
10
15
20
25
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
LBWC 5
MCL
Scenario 1A, 2068 stress period, layer 1
Mass Extracted from L1: 6 kg
Scenario 1A clay lens, 2068 stress period, layer 2
Mass Extracted from L2: 146 kg
Alternative 1B: Baseline Conservative
0
10
20
30
40
50
60
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 1
Alternative 1A - Base Treatment Alternative 1B - Base Treatment (Conservative)
MCL
0
20
40
60
80
100
120
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 2
Alternative 1A - Base Treatment Alternative 1B - Base Treatment (Conservative)
MCL
0
20
40
60
80
100
120
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
LBWC 5
Alternative 1A - Base Treatment Alternative 1B - Base Treatment (Conservative)
MCL
Scenario 1B, 2068 stress period, layer 1
Mass Extracted from L1: 58 kg
Scenario 1B, 2068 stress period, layer 2
Mass Extracted from L2: 906 kg
Scenario 1B, 2068 stress period, layer 3
Mass Extracted from L3: 155 kg
Scenario 1B, 2068 stress period, layer 4
Alternative 2A: Targeted Pumping
0
2
4
6
8
10
12
14
16
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 2
Alternative 2A - Targeted Pumping Alternative 1A - Base Treatment
MCL
Detection Limit
0
1
2
3
4
5
6
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 1
Alternative 2A - Targeted Pumping Alternative 1A - Base Treatment
Detection Limit
MCL
0
5
10
15
20
25
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
LBWC 5
Alternative 2A - Targeted Pumping Alternative 1A - Base Treatment
MCL
Scenario 2A, 2068 stress period, layer 1
Mass Extracted from L1: 6 kg
Scenario 2A, 2068 stress period, layer 2
Mass Extracted from L2: 238 kg
Alternative 2B: Targeted Pumping Conservative
0
20
40
60
80
100
120
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 2
Alternative 2A Alternative 2B Alternative 1B
MCL
0
10
20
30
40
50
60
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 1
Alternative 2A Alternative 2B Alternative 1B
MCL
0
20
40
60
80
100
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
LBWC 5
Alternative 2A Alternative 2B Alternative 1B
MCL
Scenario 2B, 2068 stress period, layer 1
Mass Extracted from L1: 53 kg
Scenario 2B, 2068 stress period, layer 2
Mass Extracted from L2: 1314 kg
Scenario 2B, 2068 stress period, layer 3
Mass Extracted from L3: 213 kg
Scenario 2B, 2068 stress period, layer 4
Alternative 3A: SW Conversion
0
1
2
3
4
5
6
1971 1978 1985 1992 1999 2005 2012 2019 2026 2033
PC
E
(
u
g
/
l
)
TKWC 1
MCL
Detection Limit
0
2
4
6
8
10
12
14
1971 1978 1985 1992 1999 2005 2012 2019 2026 2033
PC
E
(
u
g
/
l
)
TKWC 2
MCL
Detection Limit
0
5
10
15
20
25
1971 1978 1985 1992 1999 2005 2012 2019 2026 2033
PC
E
(
u
g
/
l
)
LBWC 5
MCL
Scenario 3A, 2033 stress period, layer 1
Mass Extracted from L1: 2 kg
Scenario 3A, 2033 stress period, layer 2
Mass Extracted from L2: 100 kg
Scenario 3A, 2033 stress period, layer 3
Mass Extracted from L3: 3 kg
Alternative 3B: SW Conversion Conservative
0
10
20
30
40
50
60
1971 1978 1985 1992 1999 2005 2012 2019 2026 2033
PC
E
(
u
g
/
l
)
TKWC 1
Alternative 3A - SW Conversion Alternative 3B - SW Conversion (Conservative)
MCL
0
20
40
60
80
100
120
1971 1978 1985 1992 1999 2005 2012 2019 2026 2033
PC
E
(
u
g
/
l
)
TKWC 2
Alternative 3A - SW Conversion Alternative 3B - SW Conversion (Conservative)
MCL
0
20
40
60
80
100
120
1971 1978 1985 1992 1999 2005 2012 2019 2026 2033
PC
E
(
u
g
/
l
)
LBWC 5
Alternative 3A - SW Conversion Alternative 3B - SW Conversion (Conservative)
MCL
Scenario 3B, 2033 stress period, layer 1
Mass Extracted from L1: 14 kg
Scenario 3B, 2033 stress period, layer 2
Mass Extracted from L2: 512 kg
Scenario 3B, 2033 stress period, layer 3
Mass Extracted from L3: 155 kg
Scenario 3B, 2033 stress period, layer 4
Alternative 4: 90% GAC Capacity
0
1
2
3
4
5
6
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 1
Alternative 4 - 90% GAC Capacity Alternative 1A - Base Treatment
Detection Limit
MCL
0
2
4
6
8
10
12
14
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 2
Alternative 4 - 90% GAC Capacity Alternative 1A - Base Treatment
MCL
Detection Limit
0
5
10
15
20
25
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
LBWC 5
Alternative 4 - 90% GAC Capacity Alternative 1A - Base Treatment
MCL
Scenario 4, 2068 stress period, layer 1
Mass Extracted from L1: 7 kg
Scenario 4, 2068 stress period, layer 2
Mass Extracted from L2: 463 kg
Alternative 5: 90% Well Capacity
0
1
2
3
4
5
6
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 1
Alternative 5 - 90% Well Capacity Alternative 1A - Base Treatment
Detection Limit
MCL
0
2
4
6
8
10
12
14
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
TKWC 2
Alternative 5 - 90% Well Capacity Alternative 1A - Base Treatment
MCL
Detection Limit
0
5
10
15
20
25
30
1971 1985 1999 2012 2026 2040 2053 2067
PC
E
(
u
g
/
l
)
LBWC 5
Alternative 5 - 90% Well Capacity Alternative 1A - Base Treatment
MCL
31 27 12 22 7
102 105
74
113
230
25
93
20
316
284
157
226
105
451
521
0
100
200
300
400
500
600
Alternative 1A Alternative 2A Alternative 3A Alternative 4 Alternative 5
Ma
s
s
E
x
t
r
a
c
t
e
d
(
k
g
)
TKWC 1 TKWC 2 LBWC5 Total
Mass Extracted by Well over Model Duration
0
5
10
15
20
25
30
Alternative 1A Alternative 2A Alternative 4 Alternative 5
Ye
a
r
s
t
o
P
C
E
<
4
u
g
/
l
TKWC 1 TKWC 2 LBWC5
Years to Clean Up
Note: Concentrations never exceed 4 ug/l at TKWC 1 for Alternatives 4 and 5
Questions?