Lake Koocanusa Selenium Modeling Framework

Transcription

1 Lake Koocanusa Selenium Modeling Framework Lake Koocanusa Monitoring and Research Working Group Meeting Cranbrook BC October 26, 2016 Karen E. Jenni, Science and Decisions Center, USGS With support from the Selenium Technical Subcommittee

2 Outline Goals and scope Background & Examples Draft framework Overview Mapping data (and data needs) to the framework Customizing the framework Potential sources of information Discussion 1

3 Modeling framework: Goals and Scope develop a modeling framework (conceptual model) that can be used to support the development of site-specific selenium criteria for Lake Koocanusa that is protective of sensitive fish and bird species. Focus is narrow relative to yesterday s discussions: Selenium only / criteria development focus Scope is limited Framework rather than a completely fleshed out site conceptual model (i.e., it is a starting point) Intent is to use the structure to Structure and identify connections among the existing data Highlight what can be done with information that we have Identify what additional information could improve understanding, increase confidence, and lead to a more defensible and appropriate site-specific Se criteria 2

4 Background: Ecosystemscale Selenium Model Source: Presser and Luoma,

5 Methodology description and some previous applications 4

6 Ecosystem-scale model and USEPA s conceptual model for translating egg-ovary FCV to water-column concentration Se toxicity guidelines Fish Se concentration Invertebrate concentration Particulate concentration Dissolved Se concentration 5

7 The math is straightforward, but details also matter 6

8 Details include: species, food webs, locations, seasonality, etc Sources: Presser and Luoma, 2013 / Presser

9 We ll come back to the details, but first Let s see what the basic structure gets us 8

10 Yesterday s ad hoc data in this context Dam operations & bathymetry Tributary sampling (?) Teck Se treatment results Tributary sampling LoadEst modeling Teck Baseline monitoring (Canada) LK study team 2016 monitoring (MT) MT FWP fisheries sampling (MT) Potential fish monitoring downstream of dam? USFWS Avian scouting trips Nutrients in the reservoir 9

11 What s missing? Dam operations & bathymetry Tributary sampling (?) Teck Se treatment results Tributary sampling LoadEst modeling Teck Baseline monitoring (Canada) LK study team 2016 monitoring (MT) MT FWP fisheries sampling (MT) Potential fish monitoring downstream of dam? USFWS Avian scouting trips Nutrients in the reservoir 10

12 Emerging priorities Dissolved / particulate Se concentration and Kd - At various locations within each modeling node? Fish whole-body to egg-ovary translation - At various locations within each modeling node? Understanding food web/diets of the species considered for modeling - At various locations within each modeling node? (Can we write this up as a research question for an academic project?) 11

13 Customizing the model (back to details) What sensitive fish and bird species should be the focus of the Se criteria definition? What locations / habitats within the reservoir are sufficiently different that they need to be considered separately in the modeling framework? Do we need to think about the downstream system in order to identify protective criteria for the reservoir? Does timing matter? If so, can / how do we incorporate timing considerations into recommended criteria? 12

14 Candidate species - fish To reduce data needs, the framework suggests that we should focus on species that are Present in the Lake Bioaccumulate Sensitive to Selenium Initial discussions among Se Technical Subcommittee identified a first draft list of: Westslope cutthroat trout Rainbow trout Mountain whitefish Burbot Sturgeon Yellow Perch Peamouth? 13

15 Candidate species - birds Per J. Skorupa s discussion yesterday, initial discussions among Se Technical Subcommittee identified a first draft list of: Spotted sandpiper Killdeer Swallows Osprey American Dipper? Unclear that we need to include birds specifically in the criteria development (though may be premature to rule it out) Does not appear that LK is a critically important habitat for any bird species Fish are more likely to be the limiting or determining factor/ 14

16 Location considerations Where hydrology/flow differ E.g., N-S gradient; river-like vs. lake-like conditions Where loading differs E.g., above/below Elk River Where sensitive species spend breeding seasons E.g., shorelines Practicality Not too many Places where monitoring data area already available (e.g., Teck baseline sites) 15

17 Timing considerations Both reservoir volume and loading vary seasonally Highest loadings appear to occur during breeding season for some sensitive fish species, and when the reservoir is being filled Baseline data from Teck monitoring program has not identified seasonal differences in Se concentration? 16

18 Next steps: customizing LK Se model Locations, species, timing Example: Locations 1. S. of Elk River 2. International Border 3. Forebay Physical system Reservoir levels Se loading 1 Fish species Westslope cutthroat 1,2,3 Burbot 1,2,3 Perch 1,2,3 framework (1) Primary locations Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep drawdown spawning stable / low Freshet / increasing Higher spawning Bird species Spotted sandpiper 1,2,3 breeding? Osprey 1,2,3 breeding? spawning? stable / high Food web elements??

19 Next steps: customizing LK Se model framework (2) Identify information sources, confidence, and gaps State of the Lake summary report would really help here! For selected species Determine final critical value 1 Estimate whole-body conversion factor 1 Determine / estimate food web components 2 Estimate Se concentrations in food web 3 Calculate species-specific TTF based on food web 1 Estimate Kd (EF) 3 1. Absent site-specific data, can we use values for closest related species from the USEPA criteria? 2. Does the general characterization of species as insectivorous, pescivorous, give a starting point? 3. Some site-specific data has been / is being collected 18

20 Additional issues Other contaminants that affect Se Kootenai River downstream of the Dam Trend over time Can, do, and how do we incorporate concerns about a trend of increasing concentrations over time into a protective criteria definition? 19

21 Discussion Dam operations & bathymetry Tributary sampling (?) Teck Se treatment resul Tributary sampling LoadEst modeling Teck Baseline monitoring (Canada) LK study team 2016 monitoring (MT) MT FWP fisheries sampling (MT) Potential fish monitoring downstream of dam? USFWS Avian scouting trips Nutrients in the reservoir 20

22 Optional additional discussion Using / quantifying the framework when very little data is available Can use a range of values to encompass uncertainty (e.g., TTFs?) Can use scenarios to address very large scale uncertainties (e.g., bioavailability scenarios? Future loading conditioned on treatment succeess?) Using the framework to identify the most important information needs How much would reducing uncertainty in a specific area reduce overall uncertainty and/or change what the protective criteria might be? 21