Carol DiGiorgio DWR, Mercury Monitoring and Evaluation Section - PowerPoint PPT Presentation

Carol DiGiorgio DWR, Mercury Monitoring and Evaluation Section

DES—David Bosworth BDO—Jamie Anderson, En-Ching Hsu, Hari Rajbhandari, Nicky Sandhu, Tara Smith Cody Beals, Reed Harris, David Hutchinson 2

• Delta Mercury Control Program (DMCP) and Open Water • Model Development-Delta • Model Development-Yolo Bypass • From the Sierra to the Sea-Mine Remediation and Modeling Linkages 3

What is the Delta Mercury Control Program (DMCP)? 4

78% 44% 65% O% O% 82% 65% 5

• Methylmercury (MeHg) load allocations assigned to point and nonpoint sources. The DMCP requires reductions in annual loads. *Reductions required for: • NPDES facilities • California State Lands • Municipal storm water Commission • Agricultural lands • Central Valley Flood Protection Board • Wetlands • Department of Water Open Water • Open Water Resources Work group • US Army Corps of Engineers • US Bureau of *partial list Reclamation 6

Open water allocations apply to MeHg load fluxes from the sediment to the water column. Advection/Diffusion 7

Control Studies: Delta Flooded Yolo Bypass Impacted agencies required to evaluate what operational changes or other practices could be implemented to reduce MeHg in open waters. Difficult to do this in the field. Solution? 8

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• Use modeling to examine questions on State Water Project (SWP) and Yolo Bypass flooding on MeHg supply. • Provide working models of MeHg transport and fate. • Literature, field and laboratory studies to provide info for the model. • Determine most important drivers (Sensitivity analysis) • *Scenario testing. *(TBD; based on acceptance of validation results). 10

• Delta • DSM2 + Hg algorithms Yolo (DWR + Reed Harris Bypass Environmental, Ltd.) Model Delta Model • Yolo Bypass • TuFlow + Dynamic Mercury Cycling Model (D-MCM) (Reed Harris Environmental Ltd.) 11 Highlighted area s are approximate

Delta Modeling 12

Conceptual Models Understand processes Numerical Model Development Identify key processes Prioritize key processes Represent processes in DSM2 Simulate Existing Conditions Obtain available field data Identify data gaps Calibration/validation Sensitivity testing Scenario Testing How would changes in operations affect Items in yellow are in progress mercury methylation potential? 13

DWR: Update DSM2 with new General Transport Model Calibrate/validate Evaluate impacts of Add mercury cycling DSM2 with Hg management scenarios to DSM2 using field data on MeHg in the Delta Reed Harris: Create Mercury cycling code Tasks highlighted in yellow are currently in progress DSM2: Delta Simulation Model 2 Hg: Mercury , MeHg: methylmercury 14

Yolo Bypass 15

* Models key factors Predicts Hg cycling & • bioaccumulation in aquatic systems (lakes, rivers, wetlands, marine systems.) Major sources and sinks for • total mercury and MeHg Predicts response to changes • in.. Hg loading • Environmental conditions • (e.g. climate, pH) Trophic structure • Aquatic vegetation • *Partial list 16

Information Sources: Hydrodynamics from models and field data (e.g. Tuflow) Particle dynamics Water and sediment quality from literature, field data from literature and field data and models (e.g. TuFlow) D-MCM Mercury Modeling - Abiotic Total mercury and methylmercury in water and sediments Food web Mercury Modeling – Biota from literature 17

Land use Disked land Sediment mercury Land use & disking Wetting Frequency Water covering/uncovering (% days) cycling Sediment mercury

Model testing will determine its robustness Goal--Scenario Testing Will MeHg production increase? Will MeHg production decrease? Diamond in the rough. • First cut at a Hg model for the Delta and Yolo • Bypass. Points to data gaps requiring refinement. • Serves as a jumping off point for other users to • refine inputs and ask their own questions. 19

January 2017—Begin Delta model calibration and validation Oct. 2011 Feb. 2014 Oct. 2015 Oct. 2018 Promulgated Workplan Interim Report Final Report Accepted Summer 2015—Begin initial YB model calibration and validation w/ existing field data 20

Can we link models to evaluate upstream mine cleanup to downstream impacts? 21

How can others use DWR’s model? Within the Delta Use existing model Use scenario analysis to examine reductions • of one or more non-openwater mandated DMCP sources. Outside the Delta Extend modeling domain Upstream-mine drainage impacts. • Downstream—Delta effects to San Francisco • Bay. 22

DMCP Load Allocations 23

Extend Modeling Domain Gold Mines Reservoirs and Coast river transport Range Hg mines YB Estuary Delta dynamics Reservoirs and river transport 24 USGS Fact Sheet

US EPA Environment Canada 25

Environment Canada--Six ecosystems studied with integrated model framework for Hg 26 DMCP Load Allocations

In theory could model from Sierra to the Sea, however: Linked models for Hg previously applied to simpler systems • applied mostly to isolated watersheds w/out • many anthropogenic disturbances. Terrestrial models for Hg not as well developed as • aquatic Hg models. Garbage in, garbage out. You need data to calibrate, • validate and fine tune the models. 27

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