TIE and TMDL Approaches for Legacy Sediment Contaminants: Arsenic and Petrochemical Case Studies

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1 SETAC 2002 TIE and TMDL Approaches for Legacy Sediment Contaminants: Arsenic and Petrochemical Case Studies BW Brooks, PK Turner, JK Stanley, WT Waller, TW La Point, R Palachek & JA Sullivan UNT Institute of Applied Sciences, Parsons Engineering Sciences, Inc, & Tx CEQ

2 Background to Study Study purpose: to assess presence and causes of aqueous and sediment toxicity in Texas rivers; Develop approaches to sediment toxicity identification evaluations; Focus on complex sites: Alligator Bayou and Finfeather Lake.

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5 Alligator Bayou Study Site A freshwater tributary upstream of a salt water barrier, near Port Arthur, TX. Alligator Bayou receives discharges from municipal and industrial facilities, plus smaller amount of agricultural runoff. An urban, industrial river.

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7 Finfeather Lake Study Site A small municipal waterbody located in Bryan, TX, upstream of Bryan Municipal Lake. Historically, arsenic has been the parameter of concern due to surface and groundwater contamination.

8 Standard TIE Procedures

9 TIE Procedures in this Study Initial Acute or Chronic Dilution Toxicity Test Phase I TIE Treatments at Appropriate Dilution Level Thiosulfate EDTA SIR SIR Baseline Aeration 3 Toxicity Test EDTA SIR-300 Filtration C 18 SPE Ambersorb Does TIE Treatment Statistically Improve Toxicity Relative to Corresponding Baseline Dilution Level? Yes Phase II Procedures Including Analytical Measures of Effective TIE Treatments to Screen for Suspected Toxicants Phase III Confirmation Procedures

10 TIE Procedures in this Study Treatment Chemical(s) Identified Filtration Ambersorb 563/C 18 columns SIR-300, -900/EDTA chelation Particulates/Sorptive chemicals Nonpolar organics (PAH) Metals Oxidant reduction w/thiosulfate Aeration Halides/Metals Volatile organics/surfactants

11 SIR-300 Resin Used as a parallel TIE treatment to EDTA. A cation exchange resin, styrene & divinylbenzene copolymer with iminodiacetic functional group in the sodium form, chelates divalent metal cations. Reported affinity for metals: Hg 2+ >Cu 2+ > V 2+ >Pb 2+ >Ni 2+ >Zn 2+ >Co 2+ >Cd 2+ >Fe 2+ >Be 2+ Mn 2+ >Mg 2+ = Ca 2+ > Sr 2+ >Ba 2+ >Na 2+. We found Mg 2+ and Ca 2+ to be taken out. 2+ =

12 Alligator Bayou: Effective Acute TIE Treatments Test Date Test Type/Station Organism Treatment(s) Porewater/10643 C. dubia Aeration + EDTA, C Porewater/10643 C. dubia S300, EDTA, Aeration + EDTA Sediment/10643 H. azteca None Porewater/14410 C. dubia Filt, S300, A563@24hr Porewater/10643 C. dubia C18, Filt,

13 Water Quality Criteria Used To Calculate Alligator Bayou Station 10643, Porewater Acute Toxic Units. Metal Acute Criterion 1 Source Al 991 TCEQ As 360 TCEQ Cd 104 TCEQ Cr 1000 USEPA Cu 48.6 TCEQ Fe 1000 USEPA Pb 269 TCEQ Ni 3348 TCEQ Zn 274 TCEQ 1 Acute criterion (µg/l) based on water hardness of 280 mg/l (25% station porewater) where appropriate.

14 Metal Chemistry of Alligator Bayou Sediment Porewater TIE 1 48-hour C. dubia test Metal Sed (mg/kg) 100%Base Aeration SIR 300 SIR Aeration Al As 8130 ND ND ND ND Cd 636 ND ND ND ND Cr ND ND ND Cu ND ND ND ND Fe Pb Ni ND ND Zn ND % porewater dilutions

15 Metal Toxic Units of Alligator Bayou Sediment Porewater TIE 1 48-hour C. dubia test Metal 25%Base Aeration SIR 300 SIR Aeration Al As ND ND ND ND Cd ND ND ND 0.68 Cr ND ND ND Cu ND ND ND ND Fe Pb Ni ND ND Zn ND % porewater dilutions

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18 Alligator Bayou: Results TIE identified significant toxicity reduction at 25% porewater dilution using EDTA, SIR-300 and Aeration + EDTA, but not by Aeration treatments. Toxicity reduction with these treatments suggests that metals are causative toxicants to Ceriodaphnia dubia. Chemical analysis on baseline porewater,, Aeration, SIR-300 and Aeration + SIR-300 samples indicates that SIR-300 reduced or removed Al, Cr, Fe, Pb,, Ni, & Zn.

19 Finfeather Lake: Effective Chronic TIE Treatments Test Date Test Type/Station Organism Treatment(s) Porewater/11798 C. dubia None Porewater/11798 C. dubia SIR-300, SIR Porewater/11798 C. dubia SIR-300, SIR Sediment/11798 H. azteca SIR Porewater11798 C. dubia EDTA, SIR Porewater/11800 C. dubia EDTA

20 Water Quality Criteria Used to Calculate Finfeather Lake, Station 11798, Porewater Chronic Toxic Units Hardness (mg/l as CaCO 3 ) Metal 60 mg/l 1 80 mg/l 120 mg/l 128 mg/l Al NL NL NL NL As Ba Cd Cr Cu Fe Pb Hg Ni Se Ag Zn Reconstituted moderately hard water after treatment with SIR 300 and calcium and magnesium reintroduced.

21 Finfeather Lake: Results Consistent sediment toxicity to C. tentans and H. azteca; SIR-300 and SIR-900 significantly increased C. dubia reproduction and H. azteca growth; Cu, Zn and Pb (not As) are the major players; Phase III TIE

22 Study Conclusions Currently, TSWQS do not include applicable promulgated sediment criteria. There are insufficient procedures or methods to manage Alligator Bayou sediment issues under the existing TMDL program. Alligator Bayou will require an innovative approach to solving the sediment toxicity issue. Real Issue: how to deal with legacy toxicants?!

23 Overall Recommendations TIE and Resins/Adsorbent Media Look promising: Research needed for porewaters and whole sediments TMDL approach to historical contamination: a valid approach? How to link TIE and Sediment Triad?