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Control of Toxic Chemicals in Puget Sound

Phase 3: Targeting Priority Toxic Sources

Ecology and its partners have continued in Phase 3 to develop their strategy to measure and control the sources of toxic chemicals in Puget Sound. Several of these projects have included collection and analyses of environmental samples of fresh and marine waters, sediments, atmospheric deposition, and various plants and animals. We have also continued to improve the fate and transport models of toxics chemicals in Puget Sound.

At the completion of Phase 3, a "synthesis" report will pull together the findings from all of the toxics loading studies and summarize the overall conclusions and recommendations.

Sub-Task Reports

(3A) Toxic Chemical Loadings via Surface Runoff

Purpose: To determine through seasonal sampling and analyses the actual loadings of toxic chemicals through surface runoff from 16 sub-watersheds representative of four typical land use areas (residential, commercial/industrial, agricultural, and undeveloped forest/field/other).

(3B) Modeling Surface Runoff in Pilot Watersheds

Purpose: To assist local jurisdictions to develop tools for managing stormwater, using the sub-watersheds that we studied in Sub-Task 3A. For project details, please see SUSTAIN Modeling for Controlling Toxic Chemicals in Small Streams

(3C) Evaluate Air Deposition

Purpose:Tto assess the flux of toxic chemicals directly to Puget Sound marine waters.

(3D) Toxic Chemicals in Marine Waters and from Ocean Exchange

Purpose: To evaluate the concentrations of toxics chemicals in the marine waters of Puget Sound and the exchange of those chemicals between the Sound and the Pacific Ocean. Collect marine water seasonally at two depths from three locations in the Straits of Juan de Fuca and Georgia and from four locations within Puget Sound.

Collect and analyze freshwater seasonally from the mouths of five major rivers discharging to Puget Sound to evaluate the loading of toxic chemicals to Puget Sound and the partitioning of those chemicals between the water and suspended sediments.

(3E) Numerical Models and Scenarios

Purpose: To extend the Puget Sound Toxics Box Model to include PBDEs (polybrominated diphenyl ethers), incorporate data collected in Phases 2 and 3 into the model, and use the updated model to predict possible environmental outcomes from different toxics reduction alternatives. Work is ongoing.

(3F) Priority Pollutant Scans for Publicly-Owned Treatment Works (POTWs)

Purpose: To screen representative discharges for toxic chemicals not routinely monitored and improve the loading estimates for them.

(3G) Primary Sources of Toxic Chemicals

Purpose:  To identify the primary sources of chemicals released to the environment and estimate the amounts released. This information, along with information on loading and the transport of chemicals, will help decision-makers prioritize source control activities.

(3H) Pharmaceuticals and Personal Care Products (PPCP)

Purpose: To characterize the loading of pharmaceuticals and personal care products (PPCP), and conduct preliminary assessment of wastewater treatment.

(3J) Persistent Organic Pollutants (POPs)

Purpose: To assess the effects of stormwater on biota, and determine the toxic chemical concentrations that have accumulated within certain species to better understand how various trophic levels interact within the Puget Sound food web. The subject species include: marine mammals (harbor seals), marine mammal prey (fish), plankton, and various life stages of salmonids.

(3K) Assessment Report

Purpose: To synthesize all key information from the Puget Sound Toxics Loading Studies into a single report in order to help guide an overall control strategy for toxic chemicals in the Puget Sound basin. Integrate the information on toxic chemical sources, loading, and pathways with an evaluation of the relative hazards of chemicals to identify priorities for near-term actions. The report also includes broad recommendations to address the most important chemicals and sources, and identifies data needs.

(3L) Direct Groundwater Discharge

Purpose: To develop estimates of the loading of toxic chemicals to Puget Sound through the direct discharge of groundwater to the Sound. Improving our understanding of the relative importance of the various pathways through which toxic chemicals travel to the marine environment will help guide our decisions about how best to direct resources for controlling toxics within the Puget Sound basin.


For more information about the Puget Sound Partnership's program to control toxic chemicals in Puget Sound, contact Scott.Redman at 360-464-1230

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