Anacostia River Sediment Project Current Status. September 28, 2017

Transcription

1 Anacostia River Sediment Project Current Status September 28, 2017

2 2 Topics Introduction Conceptual Site Model (CSM) Phase 2 RI Data Human Health Risk Assessment Draft Summary Ecological Risk Assessment Draft Summary Manhole Investigations (Provisional Data) Tributary Studies (Provisional Data) Next Steps

3 3 Project Study Area Anacostia River Watershed- 170 square miles Subareas Main stem of Anacostia River (9 miles long) Kingman Lake (1.8 miles long) Washington Channel (2 miles long) 14 potential environmental

4 4 Study Area Reaches Reach 7 Reach 67 Kingman Lake Washington Channel Reach 456 Reach 123

5 5 Conceptual Site Model Schematic Sediment Transport Symbols Deposition Resuspension Suspended transport

6 6 CSM: Sedimentation Trends Zone of coarse-grained sediment deposition NE Branch & NW Branch: 86% of TSS input to tidal river Zone of equilibrium (no net deposition/erosion: sediment conveyor belt Transitional from equilibrium to total deposition Zone of total deposition Potomac River sedimentation influence

7 7 Characterization CSM Data Gaps and Phase 2 Sampling Medium Data Gap defined from Phase 1 Data Collected Phase 2 (2016) Surface Sediment Characterization of sediment toxicity to fish 31 samples collected for whole sediment toxicity assessment to early life stage fish, and 5 additional samples from the Potomac River Surface Sediment Pore Water Characterization of emerging chemicals to assess potential impacts on benthic invertebrates PECS characterization Forensic data needed to refine potential sources Characterization of additional chemicals to assess potential impacts on benthic invertebrates 95 samples collected; with other PECS samples added, combined Phase 1 and 2 dataset of samples collected in Anacostia River, 9 samples collected in Tidal Basin 92 samples collected 31 samples collected Subsurface Sediment PECS characterization Collected 109 cores (1,140 samples); with other PECS samples added, combined Phase 1 and 2 dataset of 2,023 samples Forensics data needed to refine potential Collected 260 samples collected sources Sedimentation rate data needed Collected 12 cesium cores Surface Water Uncertainties regarding potential Same day seasonal wet and dry sampling performed at 24 locations concentration trends Biota Fish background uncertainties 49 whole fish samples collected from non-tidal Anacostia River. Incorporated 18 Potomac River fish fillet samples reported by USFWS for DOEE (2014) Benthic tissue uncertainties Fish diet uncertainties Turtle tissue uncertainties Crayfish tissue uncertainties 9 Clam and 11 Snail composite samples collected covering all reaches Collected 9 Hester Dendy passive samplers covering all reaches Examined stomach contents of 61 fish from the tidal river Collected 7 snapping turtles Collected 8 crayfish samples

8 Characterization CSM Data Gaps and Phase 2 Sampling (Continued) 8 Medium Data Gap defined from Phase 1 Data Collected Phase 2 ( ) Upstream Source Characterization Tributary inputs Seasonal measurement of mass loading (storm conditions) of key site contaminants from suspended sediment and bottom sediment transport to the tidal river 5 gauged tributaries and 4 minor tributaries plus low flow CSS and MS4 inputs Bottom sediment sample collection from 27 MS4 and 16 CSS outfalls

9 9 Exposure Potential for People (Human Health Risk) Media of concern Surface sediment- first half foot of sediment, Surface water, and Fish fillet Receptors (People Exposed to the Media of Concern) Waders, Swimmers, Shoreline workers, and Fishermen/Anglers Potential avenues for exposure Incidental eating and skin contact sediment Drinking and skin contact surface water Eating fish

10 10 Draft Human Health Risk Results- Sediment and Surface Water Sediment Potential Risk to swimmers and shoreline workers in Reach 456 No significant risk with sediment in other river reaches Surface Water No significant risk to swimmers anywhere in the river

11 11 There are Potential Risks with Eating Fish Risk to fishermen in the tidal Anacostia River is greatest downstream of the CSX Bridge Risk to fishermen in the Potomac River is similar to risk to Tidal Anacostia River Risk to fisherman in the Upper Anacostia River in Maryland is less than the risk in the Tidal Anacostia River but there is still a risk to eating fish there too

12 12 Chemicals that are of Concern for People Polychlorinated Biphenyls and Dioxins Exposure Pesticides Exposure Total PCB Congeners Fish ingestion 4,4'-DDD Fish ingestion Dioxin-like PCBs Dioxins Metals Fish ingestion Sediment contact Fish ingestion Sediment contact 4,4'-DDE Aldrin Chlordane Dieldrin Fish ingestion Fish ingestion Fish ingestion Fish ingestion Arsenic Fish ingestion Heptachlor Epoxide Fish ingestion Gamma-BHC (Lindane) Fish ingestion

13 13 Conceptual Site Model- Food Web

14 14 Data Evaluated in the Ecological Risk Assessment Surface Sediment Surface water Pore Water Snail, clam, crayfish and turtle tissue Whole fish from the Anacostia River, Potomac River, and Upper Anacostia River Laboratory Toxicity Tests Benthic invertebrates- survival, growth, reproduction Bioaccumulation test- invertebrates Larval fish- survival and growth

15 15 Draft Ecological Risk Assessment Results Benthic Invertebrates Bioaccumulation- build up of chemicals in tissue- observed in snails, clams, and crayfish Impairment observed at most locations but no clear link to chemicals or other causes present Birds and Mammals Little or no risk Fish Biomagnification- increasing concentrations of chemicals lower in the food chain to fish higher in the food chain Little difference between non-tidal Anacostia background and tidal Anacostia Study Area Toxic effects were infrequently observed Fish diets composed of algae and benthic invertebrates as expected (fish stomach content assessment)

16 16 Chemicals of Ecological Concern Polychlorinated Biphenyls and Dioxins Exposure Pesticides 4,4'-DDD Exposure Invertebrates and Fish Total PCB Congeners Invertebrates and Fish 4,4'-DDE Invertebrates and Fish Total Aroclors Invertebrates and Fish 4,4'-DDT Invertebrates and Fish Dioxin-like PCBs Invertebrates and Fish Chlordane Invertebrates and Fish Dioxins Semivolatile Organic Compounds Total Polycyclic Aromatic Hydrocarbons Metals Mercury Invertebrates and Fish Invertebrates and Fish Invertebrates and Fish Dieldrin Endrin Endosulfan Sulfate Heptachlor Epoxide Gamma-BHC (Lindane) Invertebrates and Fish Invertebrates and Fish Invertebrates and Fish Invertebrates and Fish Invertebrates and Fish

17 17 Waste Disposal Practices Industrial Direct Discharges Storm Sewers Agricultural Chemical Use Landfills Illegal Dumping Contaminated Groundwater

18 18 Potential Sources Upstream Contamination from Tributaries- Studies On-going Agricultural and Urban Runoff Storm Sewers Discharge Pipes- Studies On-going 14 Potential Environmental Cleanup Sites- Studies On-going Contaminated Groundwater- Studies On-going

19 Manhole Studies- Current Status Reach Number of Manholes Accessed Number of Sediment Samples Collected Additional Manholes Completed in September 2017 Sampling Round Tidal Basin Washington Channel Reach Kingman Lake Reach Reach Reach Total

20 Outfalls/Manholes included in the Manhole Study

21 Total PCB Congener Concentrations in Outfall Manhole Bottom Sediment (Provisional data subject to change) Reach Outfalls Maximum Concentration (µg/kg) Kingman Lake F Reach 456 NPDES Reach 123 F Reach 123 NPDES Reach 123 F Reach 123 F Reach 123 F Reach 123 NPDES 006 No data Washington Channel F Washington Channel F Washington Channel F Tidal Basin F Tidal Basin F Tidal Basin F

22 Objectives of DOEE Tributary Study 1. Load of suspended sediment and organic contaminants in: NE and NW Branches of the Anacostia River Lower Beaverdam Creek Watts Branch Hickey Run PCBs, PAHs, Pesticides, Metals {Large Volume Samples} 2. Provide representative concentrations and loads in 4 smaller tributaries for TMDL model and track-down efforts Nash Run Pope s Branch Ft. DuPont Creek Ft. Stanton Creek

23 NWB NEB Hickey LBDC Watts Small Tributaries

24 Newly Installed LBDC Stream Gage and Sampling Station- September 2016

25 Gaging-Sampling Station on Lower Beaver Dam Creek Side-looking Acoustic Doppler Velocity Meter allows tidal influence to be removed from Q totals sampling only during periods of down-stream flow Real-time data Q, V, turbidity, SC Cellular control of samplers

26 Continued Calibration of LBDC Discharge >120 calibration measurements Discharge: 2.3 to 745 cfs Stage: 0.1 to >5.0 ft Maximum Velocities: 7.8 ft/s -1.0 ft/s ~Time from rain to rise: 30 to 60 minutes

27 Oct-Nov 2016 Samples Collected to Date LBDC Hickey Watts NEB NWB Low Flow Low Flow -- Low Flow Low Flow PCB/PAH Dec 16, 2017 Storm Storm Storm PCB/PAH Jan Storm Storm -- Storm Storm PCB/PAH March 31, 2017 April 6, 2017 Storm Storm Storm Storm Storm PCB/PAH Storm Storm (discrete) May 5, 2017 Storm Storm Storm Storm Storm July Low Flow PCB/PAH PCB/PAH Pesticides PCB/ Pesticides Watts Branch Low flow sample contains oil, will be resampling

28 Storms Sampled for Suspended Sediments (SS) and Particulate Organic Carbon (POC) Stream # Storms LBDC 13 Watts 13 Hickey 8 NEB 13 NWB 9 Needed for loading models relating SS/POC to Discharge (Q) and turbidity

29 Hickey Run, March 31- April 1, Gage height 4 Sampled interval 250 Turbidity Gage height, in feet Total sediment mass collected = 45.4 grams Total Q during event = 12.7 MG Total Q during sampling = 12.5 MG Percentage of discharge sampled = 98 % Turbidity, in NTU :00 6:00 12:00 18:00 0:00 6:00 12:00 0

30 Small Non-gaged Tributaries Sampled to Date Stream Low Flow Storm Nash Run 7/25/17 7/28/17 Pope s Branch 8/2/17 8/7/17 Ft. DuPont Creek TBD 8/12/17 9/2/17

31 Small Streams Difficult to sample during storms, rain passes quickly Evidence of considerable SS load, and GW inflow Ft. DuPont 8/12/ Gage height in feet PPT at Hickey Run 2 Hours Precipitation in inches 0 16:00 16:10 16:20 16:30 16:40 16:50 17:00 17:10 17:20 17:30 17:40 17:50 18:00 18:10 18:20 18:30 18:40 18:50 19:00 19:10 19:20 19:30 19:40 19:50 20:00 20:10 20:20 20:30 20:40 20:50 21:00 21:10 21:20 21:30 21:40 21:50 22:00 22:10 22:20 22:30 22:40 22:50 23:00 23:10 23:20 23:30 23:40 23:50 0

32 Ft. DuPont CSX Yard Storm Flow

33 Ft. DuPont During Dry Weather

34 Total PCB Concentrations in Sediment (Provisional Data subject to change) LOW FLOW Conc. ug/kg STORM Maximum Total Conc. ug/kg Maximum Congener In storm sample Conc. ug/kg LBDC /70/74/ HICKEY 1, /138/160/ 163 WATTS? 20 90/101/ NEB /138/160/ NWB /138/160/

35 35 Cleanup Process Preliminary Assessment Site Investigation Remedial Investigation Feasibility Study Proposed Plan Record of Decision Remedial Design Remedial Action Long-term Management

36 36 Current Project Status Phase 1 Remedial Investigation and 2015; Phase 2 Remedial Investigation Field Work Tributary Studies- On-going Manhole/Outfall Investigations- Complete Passive Samplers and Mussel Studies- On-going Passive Sampler Air Deposition Studies- On-going Draft RI Report- Winter 2018 Draft Feasibility Study Report Winter 2018 Updating ARARs Developing Remedial Action Objectives Developing Preliminary Remedial Goals Remedial Alternatives Screening Detailed Analysis of Retained Alternatives Record of Decision- 2018

37 37 Questions?