One TMDL for Zinc in Oyster Tissue in Nueces Bay
Faith Hambleton, Program Manager Total Maximum Daily Load Program Texas Commission on Environmental Quality TMDL Components
¾ Background Project Information ¾ Problem Definition ¾ Endpoint Identification ¾ Source Analysis ¾ Link Between Sources and Receiving Water ¾ Pollutant Load Allocation ¾ Reasonable Assurance of Implementation ¾ Public Participation Watershed Area Goals and Authority
¾Clean Water Act requires states to: ¾ establish water quality standards (WQS) ¾ identify waters not meeting WQS (303d List) ¾ develop TMDLs ¾Coastal Bend Bays & Estuaries Program ¾WSQ-1 Implement plans to improve water and sediment quality in identified segments. ¾Bays Plan- identified community concerns Problem Definition
Zinc in Oyster Tissue in Texas Bays 1969-2002
3000 2500 2000 1500 1000 500 0 y y re a a y ay a d
Zinc in Oyster Tissue (mg/kg) Tissue Oyster in Zinc e re y a B B Bay B Bay B ake A a e s Bay s Ba Ma L te Bay p rt Lak it a e risti a e o o os Bay a nio u s c n n tr p i u q n e u i s e to s opano u Ch g b tagord n ra N s a a Trinity Bay Ba e a A C A u S Fr ncah Me L Chocola M n GalvestonGalveston Bay Bay t ra a s S Corp Ea Tres PalacCa PowderhornEspiritu Lake Santo Bay East West Galveston Bay Zinc in Nueces Bay Oyster Tissue (1980-2005)
3000
2500
2000
1500
1000
500
0 1980 1982 1983 1984 1994 2002 2005 Annual Avg Zinc (mg/kg) Avg Zinc Annual
n=4 n=2 n=2 n=2 n=2 n=12 n=25 Endpoint Identification
¾ TSHS’s health assessment comparison value: 700 mg zinc/kg oyster tissue
¾ HAC value assumes: ¾Body weight = 70 kg (154 lbs) ¾Consumption rate = 30 g/day (or 8 oz/wk) ¾30-year exposure rate Water QualityTarget
¾Bioconcentration factor (BCF) = tissue:water
¾Zinc BCF = 23,820 L/kg (USEPA, 1987)
¾23,820 L/kg = 700 mg/kg/ [Zn water] target zinc concentration in Water = 29 ug/L Historical Water Data (from Mrini, et al., 2003)
160.0 Total zinc in Nueces Bay 140.0
120.0
100.0
80.0
60.0 Mean = 46.8µg/l Conc (µg/L) Conc 40.0
20.0
0.0 1/1/80 5/15/81 9/27/82 2/9/84 6/23/85 11/5/86 3/19/88 8/1/89 Date
13422 13421 13420 13423 Historical Water Data (from Mrini, et al., 2003)
70.0 Total zinc in CC Inner Harbor 60.0
50.0
40.0 Mean = 37µg/L 30.0
20.0 Conc (µg/L)
10.0
0.0 12/1/80 8/28/83 5/24/86 2/17/89 11/14/9 8/10/94 5/6/97 1/31/00 1 Date 13430 13429 13432 13439 Historical Sediment Data (from Mrini, et al., 2003) 400 Zinc in sediments of Nueces Bay 350 (1980- 2002) 300
250 Mean = 92.8 mg/kg 200
150
100
Conc (mg/kg dry weight)(mg/kg Conc 50
0 1/1/80 9/27/82 6/23/85 3/19/88 12/14/90 9/9/93 6/5/96 3/2/99 11/26/01 8/22/04
Date Data source TCEQ CCBNEP Carr et al Historical Sediment Data (from Mrini, et al., 2003)
Zinc in se dime nts of the Inne r H arbor (1980-2002)
TCEQ stations 6000 13430 13432 5000 13439 Mean = 497 mg/kg 13433 4000 13434 Mean = 497 13435 3000 mg/kg 13436 13437
Conc. (mg/kg) 2000 13438 13429 1000 13428 13427 0 1/1/80 6/23/85 12/14/90 6/5/96 11/26/01 Date Source Analysis
¾ Total zinc loadings Model (Mrini, et al., 2003)
¾ CSTR model ¾ Nonpoint sources (GIS-based watershed model) ¾Upstream watershed ¾Adjacent watershed ¾ Atmospheric deposition (dry) ¾ Point sources ¾Municipal ¾Industrial Non-point Sources into Nueces Bay (frm Upstream Watershed)
LOADINGS
Background zinc concentration for freshwater. Load = 4.27 Kg/day
Flow from USGS gauge on Nueces River Q = 2.47 m3/s Non-point Sources (frm NB Adjacent Watershed)
Precipitation Runoff LOADINGS Land Use/ Load = 3.69 Kg/day Land Cover
Q = 1.83 m3/s EMC Concentration Atmospheric Source
LOADINGS (Atmospheric deposition1) (bay area) Load = 18.67 Kg/day
1Wade, et al., 2000 Permitted Point Sources
Name Permit No. Permit type Max permitted flow (MGD) Nueces Bay WQ0001244-000 Industrial 500 Power Station City of Portland WQ0010478-001 Municipal 2.5
Sublight WQ0011096-001 Municipal 0.009 Enterprises Inc. City of Odem WQ0010297-002 Municipal <1 (pending) Point Sources (Municipal)
LOADINGS (Typical Pollutant Concentration1 0.165 mg/l) (Permitted Flow) Load = 1.57 Kg/day
1Armstrong and Ward, 1998 Point Sources (Industrial)
(Avg. zinc concentration in CCIH LOADINGS 37ug/l) (Permitted Flow from Nueces Bay Power Station 500 MGD) Load = 70.01 Kg/day Total Zinc Loads Source Load (kg/d) % NPS Upstream 4.27 4.35 Adjacent 3.69 3.76 Atm. Dep. 18.67 19.01 Subtotal 26.63 27.1 PS Municipal 1.57 1.6 Industrial 70.01 71.3 Subtotal 71.58 72.9 Total 98.2 100 Modeled vs. Observed
Total Zinc in Nueces Bay (1980-1988)
160.0 140.0 120.0 100.0 80.0 Observed/TCEQ Data 60.0 Mean = 46.8µg/L 40.0 Modelled results Concentration (µg/L) 20.0 = 44.5 ug/L 0.0 1/1/80 5/15/81 9/27/82 2/9/84 6/23/85 11/5/86 3/19/88 8/1/89 Date Pollutant Load Allocation
Scenario Load Conc. Flow (m3/s) (kg/d) (ug/l) Current 98.2 61.4 26.31
Target 65.9 29 26.31
Load Reduction 32.3 ------needed Pollutant Load Allocation
TMDL = ∑LA + ∑ WLA+ AFG
TMDL = 26.6 kg/d + 32.6 kg/d + 6.7 kg/d TMDL = 65.9 kg/d
Where ∑LA = subtotal for NPS (26.6 kg/d), ∑WLA = subtotal for PS (71.58 kg/d) – load reduction (32.3 kg/d), and AFG = 10% of TMDL (65.9 kg/d) New Data (June 2004 to May 2005)
¾ Parameters: ¾ Zinc in water and sediment ¾ Field (temp., DO, salinity, pH, cond., etc.) ¾ Other (TOC, total solids, TSS, sediment grain size) ¾ Frequency: ¾ Quarterly for water ¾ Biannually for sediment ¾ Stations: ¾ 8 in Nueces Bay, 2 in Nueces River ¾ 4 in Corpus Christi Inner Harbor Nueces ZINC TMDL ProjectNew Data ¯
12961
13423 13425 13424 13420 Nueces River 12960 13439 Nueces Bay 13422 13421
18365 AEP-CPL Power Plant 14833 13436 13432 13430
City of Corpus Christi
051234 Kilometers Power Stn Flows
Nueces Bay Power Station Permit no. WQ0001244000
600 500 400 300 200 100 0 3 4 9 0 01 02 03 l-04 Average Monthly Flow (MGD) 98 99 -00 ul- n-0 ul Jul- an-0 J Ja Ju Jan-05 Jul- an-0 J Jan-01Jul- Jan-02 J Jan-98Jul- Jan-9 J
9
43
3
1
3436
1
2
3
34
1
0
1343
8365
1
3
83
4
1
13425
4
2 Station
34
1
3
Nueces Bay Inner Harbor
1342
2
2
34
1
1
42
3 1
(June 2004-May 2005) 13420
1
6
29
1
0
96
2 1 Dissolved Zinc in Water Nueces River
8.00 0.00 6.00 2.00 4.00
12.00 10.00 Dissolved Zinc (ppb) Zinc Dissolved Average Dissolved Zinc (2004-05)
Waterbody Avg. Diss. Zinc (ug/l) Nueces River tidal 0.21
Nueces Bay 1.11
Corpus Christi Inner Harbor 5.12 Nueces Bay TMDL Mean Dissolved Zinc (ppb)
< 0.268 0.268 - 0.886 ¯ 0.887 - 1.323
1.324 - 6.085
12961
13423 13425 13424 Nueces River 13420 12960 13439 Nueces Bay 13422 13421
18365 AEP-CPL Power Plant 14833 13436 13432 13430
City of Corpus Christi
051234 Kilometers Nueces Bay Average Dissolved Zinc 1999-2004
10
8
6
4
2 Dissolved Zinc(ug/l) 0 1999 2000 2001 2002 2003 2004 2005
39
4
3
1
36
4
3
1
13432
30
4
3
1
18365
3
3
8
4
1
3425
1
4
2 Station
134
3
2
4
3 Nueces Bay Inner Harbor 1
3422
1
1
2
134
3420
1
1
6
129
60
9
2 1 Total Zinc in Water Nueces River
0.00
10.00 50.00 30.00 20.00 40.00 Total Zinc (ppb) Zinc Total Average Total Zinc
Segment Avg. Tot. Zn (ug/l) Nueces River tidal 4.63
Nueces Bay 10.15
Corpus Christi Inner Harbor 7.93 Nueces Bay TMDL Mean Total Zinc (ppb)
< 3.60 3.60 - 7.18 ¯ 7.19 - 11.03
11.04 - 13.85
12961
13423 13425 13424 Nueces River 13420 12960 13439 Nueces Bay 13422 13421
18365 AEP-CPL Power Plant 14833 13436 13432 13430
City of Corpus Christi
051234 Kilometers Nueces Zinc TMDL Total Suspended Solids Mean Concentrations (mg/L) < 25.00 ¯ 25.01 - 50.00
50.01 - 75.00
> 75.00
12961
13423 13425 13424 Nueces River 13420 12960 13439 Nueces Bay 13422 13421
18365 AEP-CPL Power Plant 14833 13436 13432 13430
City of Corpus Christi
051234 Kilometers Sediment (Upper): Mean Zinc (mg/kg)
< 31.00 31.00 - 62.00 ¯ 62.01 - 124.00 124.01 - 197.50 (TEL) 197.51 - 271.00 > 271.00 (PEL)
12961
13423 13425 13424 Nueces River 13420 12960 13439 Nueces Bay 13422 13421
18365 AEP-CPL Power Plant 14833 13436 13432 13430
City of Corpus Christi
051234 Kilometers Public Comment 303(d) List TCEQ Approval
Initiate TMDL EPA Approval Projects for Impaired Waters Public Comment
TMDL TCEQ Approval Allocation Report
Develop Implementation Plan
Stakeholders Implement The Plan Implementation Plan Strategy
¾ Phased Implementation: ¾ I. Reduce NBPS zinc load ¾ II. Investigate source of atmospheric deposition ¾ III. CCIH dredging options ¾ Continue monitoring water, sediment and tissue ¾ Evaluate progress toward achieving TMDL on a continuing basis ¾ Hold regular stakeholder meetings Load Reduction Scenarios L = Q * C , where L = load (kd/d), Q = flow (m3/s), and C = concentration (ug/l) then:
% flow reduction Reduced flow (m3/s) Avg. Total zinc in Zinc load from CPL Load reduction Q CCIH (kg/d) (kg/d) C L 100 0 37 0 70.01 90 2.19 37 7.0 63.01 80 4.38 37 14.0 56.01 70 6.57 37 21.0 49.01 60 8.76 37 28.0 42.01 50 10.95 37 35.0 35.01 40 13.14 37 42.0 28.01 30 15.3 37 48.91 21.10 20 17.5 37 55.94 14.07 10 19.7 37 62.98 7.03 www.tnrcc.state.tx.us/water/quality/tmdl/
Faith Hambleton, Program Manager [email protected]
Sandra Alvarado, Project Manager [email protected] 512/239-6643