Figure 1.Evaluation of simulated monthly salinity profiles for the low flow year 2001 (Data source: USGS)
Figure 2.Evaluation of simulated monthly TSM profiles for the low flow year 2001 (Data source: USGS)
Figure 3.
Evaluation of simulated monthly chlorophyll a profiles for the low flow year 2001 (Data source: USGS)
Figure 4.Evaluation of simulated monthly salinity profiles for thehigh flow year 2005 (Data source: USGS)
Figure 5.Evaluation of simulated monthly TSM profiles for thehigh flow year 2005 (Data source: USGS)
Figure 6.Evaluation of simulated monthly chlorophyll a concentration profiles for the high flow year 2005 (Data source: USGS).
Figure 7. Simulated time series of TSM concentrations compared to observed data from USGS at stations 3 (Suisun Bay), 6 (Suisun Bay), 14 (San Pablo Bay) and 18 (Central Bay). (Data source: USGS).
Figure 8. Simulated time series of chlorophyll a (Chl a) concentrations compared to observed data from USGS at stations 3 (Suisun Bay), 6 (Suisun Bay), 14 (San Pablo Bay) and 18 (Central Bay). (Data source: USGS).
Table 1.
Selenium Loads from Point Sources and Tributaries
1 / San Rafael / Tributary / 80.9 / 0.207*
2 / Berkeley / Tributary / 87.9 / 0.103*
3 / San Francisco Bayside / Tributary / 95.1 / 0.037*
4 / Novato / Tributary / 70.9 / 0.155*
5 / PetalumaRiver / Tributary / 68.9 / 0.177*
6 / Sonoma Creek / Tributary / 65.5 / 0.188*
7 / NapaRiver / Tributary / 55.1 / 0.530*
8 / Pinole / Tributary / 72.6 / 0.127*
9 / Fairfield / Tributary / 36.8 / 0.367*
10 / Concord / Tributary / 41.2 / 0.407*
11 / Tesoro / Refinery / 42.1 / 0.19
12 / Valero / Refinery / 44.1 / 0.2
13 / Shell / Refinery / 45.9 / 0.59
14 / ConocoPhillips / Refinery / 59.2 / 0.16
15 / Chevron / Refinery / 76.8 / 0.33
16 / City of AmericanCanyon / Municipal / 56.0 / 0.008
17 / City of Benicia / Municipal / 46.8 / 0.010
18 / Central Contra Costa / Municipal / 41.1 / 0.060
19 / Central Marin / Municipal / 8.0 / 0.034
20 / Delta Diablo / Municipal / 19.3 / 0.177
21 / EBMUD / Municipal / 98.9 / 0.095
22 / Fairfield Suisun Sewer / Municipal / 37.8 / 0.052
23 / Las Gallinas / Municipal / 74.0 / 0.009
24 / MountView / Municipal / 44.3 / 0.006
25 / NapaS.D. / Municipal / 56.0 / 0.011
26 / City of Petaluma / Municipal / 71.6 / 0.019
27 / Cities of Pinole and Hercules / Municipal / 58.4 / 0.011
28 / Rodeo / Municipal / 59.0 / 0.002
29 / Sausalito-Marin / Municipal / 95.4 / 0.015
30 / US Navy Treasure Island / Municipal / 96.0 / 0.001
31 / Vallejo Sanitation / Municipal / 54.5 / 0.056
32 / West County Agency WCA / Municipal / 84.9 / 0.092
33 / Rhodia Basic Chemical / Industrial / 43.5 / 0.004
34 / Dow Chemical / Industrial / 20.7 / 0.006
35 / General Chemical / Industrial / 29.7 / 0.005
36 / GWF (I) / Industrial / 26.1 / 0.001
37 / GWF (V) / Industrial / 31.9 / 0.0004
38 / USS-Posco / Industrial / 20.1 / 0.031
*tributary loads are highly variable; the loads shown are mean daily loads.
Table 2.
Literature values for first order rate constants for selenium transformations
k1 / P Se(-II) → D Se(-II) / Mineralization of particulate organic selenide / 1.3× 10-5-5×10-2 / d-1 / Regeneration experiments (Cutter, 1992)
k2 / D Se(-II) → D Se (IV) / Oxidation of dissolved organic selenide / 1.0×10-3 - 81.0 / d-1 / Surface and deep Pacific water (Suzuki et al. 1979, cited in Cutter, 1992)
k3 / D Se(IV) → D Se (VI) / Oxidation of dissolved selenite / 2.4×10-6 / d-1 / Deep Pacific, Cutter and Bruland (1984)
k4 / D Se(IV) → P Se (-II) / Uptake of dissolved selenite by phytoplankton / 2.02-2.41
(15.8-18.8)
0.07-0.21*
(225.8-777.8)* / μmol Se (g chl)-1hr-1
(l/g chl a/hr)
pmol Se (ug chl)-1hr-1
(l/g chl a/hr) / Riedel et al. (1996)
Baines et al. (2004)
k5 / D Se(VI) → P Se (-II) / Uptake of dissolved selenate by phytoplankton / 0.43-0.58 / μmol (g chl)-1hr-1 / Riedel et al. (1996)
k6 / D Se(-II) → P Se (-II) / Uptake of dissolved organic selenide by phytoplankton / 0.5 k4 / μmol (g chl)-1hr-1 / Baines et al. (2001)
a’ / D Se(IV)_ → PSe (IV) / Mineral adsorption of selenite / 0.1-0.8 / l/g/d / Zhang and Sparks (1990)
b / PSe(IV) → D Se(IV) / Desorption of adsorbed selenite / Kd/a’ / d-1 / Zhang and Sparks (1990)
Table 3.
Sensitivity Analysis for Changing Parameters by 50% During Low Flow (Nov. 1999).
|Sc,k| < 0.15 is Insensitive.
(ug/g)
SeVI SacRiv (+) / Selenate concentrations from Sacramento River / 0.418 / 0.006 / 0.024 / 0.004 / 0.010
SeVI SacRiv (-) / Selenate concentrations from Sacramento River / 0.195 / -0.002 / 0.008 / -0.001 / 0.003
SeIV SacRiv (+) / Selenite concentrations from Sacramento River / 0.244 / 0.021 / 0.002 / 0.009
SeIV SacRiv (-) / Selenite concentrations from Sacramento River / 0.097 / 0.007 / 0.001 / 0.003
OrgSe SacRiv (+) / Organic Selenide concentrations from Sacramento River / 0.399 / 0.084 / 0.029 / 0.012
OrgSe SacRiv (-) / Organic Selendie concentrations from Sacramento River / 0.181 / 0.030 / 0.010 / 0.004
SeVI SJR input (+)
Delta Removal Constant) / Delta Removal Constant for selenate / 0.020 / 0.001 / 0.001
SeVI SJR input (-)
(Delta Removal Constant) / Delta Removal Constant for selenate / 0.007
SeIV SJR input (+)
(Delta Removal Constant) / Delta Removal Constant for selenite / 0.000
SeIV SJR input (-)
(Delta Removal Constant) / Delta Removal Constant for selenite / 0.001
SeII SJR input (+)
(Delta Removal Constant) / Delta Removal Constant for organic selenide / 0.034 / 0.007 / 0.003 / 0.001
SeII SJR input (-)
(Delta Removal Constant) / Delta Removal Constant for organic selenide / 0.012 / 0.002 / 0.001
Riverine PSe0 (+) / Riverine particulate elemental selenium / 0.269 / 0.044
Riverine PSe0 (-) / Riverine particulate elemental selenium / 0.109 / 0.015
Riverine PSeII (+) / Riverine particulate organic selenide / -0.004 / -0.001 / 0.214 / 0.081
Riverine PSeII (-) / Riverine particulate organic selenide / 0.002 / 0.061 / 0.019
Riverine Pseivvi (+) / Riverine particulate adsorbed selenite and selenate / 0.304 / 0.071
Riverine Pseivvi (-) / Riverine particulate adsorbed selenite and selenate / 0.127 / 0.025
Refinery SeIV (-) / Refinery selenite concentration / 0.026 / 0.010 / 0.004
Refinery SeIV (+) / Refinery selenite concentration / 0.073 / 0.003 / 0.001
K4(+) / Selenate uptake rate by phtoplankton / 0.002 / -0.006 / -0.006 / 0.063 / 0.029
K4 (-) / Selenate uptake rate by phtoplankton / 0.001 / -0.002 / -0.002 / 0.022 / 0.010
K5 (+) / Selenate uptake rate by phtoplankton / 0.003 / -0.029 / 0.089 / 0.042
K5 (-) / Selenate uptake rate by phtoplankton / 0.001 / -0.010 / 0.032 / 0.015
K6 (+) / Selenate uptake rate by phtoplankton / -0.011 / -0.002 / 0.058 / 0.027
K6 (-) / Selenate uptake rate by phtoplankton / -0.004 / -0.001 / 0.020 / 0.009
a (+) / Selenite adsorption rate
a (-) / Selenite adsorption rate / 0.001
Phytoplankton growth rate (+) / Phytoplankton growth rate / 0.047 / 0.062 / 0.245 / -0.617 / -0.295
Phytoplankton growth rate (-) / Phytoplankton growth rate / -0.002 / -0.002 / -0.011 / 0.085 / -0.015 / 0.023
PSeII mineralization rate k1 (+) / Particulate organic selenide mineralization rate / 0.030 / -0.161 / -0.070
PSeII mineralization rate k1 (-) / Particulate organic selenide mineralization rate / 0.012 / -0.055 / -0.025
kd (+) / Partition coefficient for selenite / -0.004 / -0.002 / 0.005 / 0.006 / 0.001
kd (-) / Partition coefficient for selenite / 0.001 / 0.001 / -0.002 / 0.002 / 0.001
a (+) / Adsorption rate of selenite / -0.004 / -0.002 / 0.005 / 0.008 / 0.001
a (-) / Adsorption rate of selenite / 0.001 / 0.001 / -0.002 / -0.001 / 0.000
Qsac (+) / Sacramento River Discharge / -0.026 / -0.039 / -0.244 / 0.032 / 0.323 / -0.269
Qsac(-) / Sacramento River Discharge / -0.030 / -0.018 / -0.050 / -0.331 / 0.120 / -0.241
Phytoplankton Se in seawater (+) / Phytoplankton Se in seawater / 0.012 / 0.001 / 0.395 / 0.297
Phytoplankton Se in seawater (-) / Phytoplankton Se in seawater / 0.004 / 0.000 / 0.179 / 0.123
Riverine phytoplankton Se (+ ) / Riverine phytoplankton / 0.054 / 0.040 / 0.032 / 0.039 / 0.187 / 0.031 / 0.018
Riverine phytoplankton Se (-) / Riverine phytoplankton / -0.018 / -0.007 / -0.011 / -0.012 / 0.047 / -0.010 / -0.006
Ubeps (+) / Scaling factor for BEPS / -0.001 / 0.012 / 0.645 / 0.706 / 1.539 / -0.162
Ubeps (-) / Scaling factor for BEPS / 0.003 / 0.002 / 0.003 / 0.071 / 0.112 / 0.558 / -0.101
Kbeps (+) / Scaling factor for BEPS / -0.008 / -0.006 / -0.011 / -0.180 / -0.318 / -1.543 / 0.305
Kbeps (-) / Scaling factor for BEPS / -0.001 / -0.005 / -0.408 / -0.437 / -0.725 / 0.084
c (+) / factor relates freshwater
discharge and sedimentinput / 0.372 / 0.011 / 0.113 / 3.033 / 3.783 / 4.157 / -2.559
c (- ) / factor relates freshwater
discharge and sediment input / 0.036 / 0.070 / 0.302 / -0.962 / 1.451 / 2.865 / -1.135
(Kw) (+) / Dispersion coefficient / -0.148 / -0.181 / -0.108 / 0.080 / 0.134 / 0.418 / 0.023
(Kw) (-) / Dispersion coefficient / -0.074 / -0.086 / -0.059 / 0.038 / 0.036 / 0.196 / 0.067
+: +50%
-: -50%
The sensitivity is defined as the ratio between the relative changes in resulted parameters to the relative changes in the inputs (Sc,k) as follows:
Sc,k = (1 - Cr/Cs)/(1-Kr/Ks)
where Cr = reference concentrations, Cs = simulation result when Kr is changed
Kr = reference parameter value, Ks is the adjusted parameter value. The variation of ± 50% is approximately the same magnitude of variation as observed in particulate selenium content on riverine particulates and delta selenium load removal constant.