and Major Tributaries

swedishstreakMechanics

Feb 22, 2014 (3 years and 10 months ago)

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Toxic Chemicals in Puget Sound
and Major Tributaries

Tom Gries and David Osterberg

Washington State Department of Ecology

Introduction


Puget Sound Toxics Loading Analysis


Compiled relevant information, estimated loads,
identified data gaps


Developed box model for transport and fate of
toxic chemicals

(Poster session
10D
)


Estimated loading after land use
-
based water
quality monitoring in two watersheds

(Wed
6A
)


Estimated loading from ocean exchange and
from monitoring near mouths of major rivers


Synthesis

(Platform session
1A
)

Goals


Provide concentration data for toxic
chemicals entering Puget Sound


To reduce uncertainty of outputs from Puget
Sound Toxics Box Model →



Provide concentration data for toxic
chemicals in Puget Sound


To calibrate the Box Model

Objectives


Measure concentrations of toxics in:


Surface and deep waters of Puget Sound basins
and ocean boundary waters


Five largest tributaries to Puget Sound


Suspended particulate matter (SPM) at the
same marine and freshwater sites


Evaluate spatial and temporal variability in
concentrations


Calculate loads

Sampling Design: Marine Waters


7 stations representing

Box Model cells and

main ocean boundary


2 depths per station


3 seasons: summer,
fall, and winter


TSS
, organic carbon, and metals similar to other
studies; most organics seldom detected









POC
, total zinc, and
PBDEs

most variable


Total PCBs < recent Canadian study


Total PBDEs often 10X Canadian study

Results: Marine Water Column

Parameter

(
UOM
)

Det
.

Freq
.

Min
.

Median

Mean

CV

Max
.

TSS (mg/L)

100

0.8

1.6

1.7

0.6
0

6.0

DOC (mg/L)

10
0

0.61

0.75

0.76

0.12

0.97

POC (mg/L)

100

0.03

0.06

0.13

2.44

1.78

TOC (mg/L)

100

0.66

0.81

0.89

0.43

2.75

Total

A
rsenic

(
µ
g/L)

100

1.16

1.41

1.42

0.06

1.56

Total

C
admium

(
µ
g/L)

100

0.059

0.084

0.085

0.1
2

0.112

Total

C
opper

(
µg/L)

100

0.19

0.3
8

0.41

0.5
2

1.37

Total

Lead

(
µg/L)

88

0.015

0.07
0

0.085

0.6
4

0.23
0

Total

Zinc

(
µg/L)

100

0.41

0.69

0.86

1.2
3

7.4
4

Total PCBs (pg/L
)

100

6.09

24.0

26.3

0.57

75.1

Total PBDEs (pg/L)

24

51
.0

749

2
,
86
0

1.98

18
,
700


Results: Spatial Variability


DOC, copper, lead, PCBs: PS > OB


Cadmium: ocean boundary > Puget Sound




Deep > Surface


Arsenic, total lead


Total PCBs →


Surface > Deep


DOC in ocean
boundary waters

Results: Spatial Variability

Results: Ocean Exchange


Net exchange = Mass
exported



Mass
imported


Mass exported = volume
out
x

flow
-
weighted concentrations of
surface layer at Main, Whidbey and Hood Canal basin sites


Mass imported = volume
into

Puget Sound
x

concentrations of
deep layer at Haro Strait and San Juan de Fuca sites


EB
SI
CB

Boundaries


Admiralty Inlet


Deception Pass


2
-
layer circulation


Deep water flows
into

Puget Sound


Surface water flows
out
of

Puget Sound


Based on model
-
predicted water fluxes and

25
th
-
75
th

percentile concentrations













Most parameters
exported


Cadmium and lead
imported



Results: Ocean Exchange

Parameter

Estimated Net Exchange

(
mT
/yr
)

Direction of Net Transport

(based on current study)

TSS

+160
-
330 x10
3

Export

TOC

+240
-
400 x10
3

Total

Arsenic

+24
-
28

Total

Cadmium

-
3.2 to
-
3.9

Import

Total

Copper

+30
-
110

Export

Total Lead

-
18 to
-
20

Import

Total Zinc

0
-
150

Export

Total PAHs

-
6 to +9

Un
cert
a
in



based on ND

Total PCBs

-
0.001 to +0.001

Un
certain



insuff
icient

data

Total PBDEs

-
3.8 to
+0.2

Un
cert
a
in



data too variable


Sampling Design: Marine SPM

Sediment traps


Five sites and 1
-
2 depths


Represented Box Model
boundaries / cells


From Nov ‘09


Jan ‘10



Results: Marine
SPM



Only recovered deep Hood Canal traps
!


Analyzed
SPM

from ‘08 South Sound traps


Gross sedimentation < urban embayments


Chemical fluxes in Hood Canal < in South
Sound (except copper)


Rates can be compared to Box Model
-
predicted sedimentation losses

Conclusions: Marine Waters


Detected parameters found in low concentrations


Organic carbon, metals, and PCB concentrations
similar to other studies


Semivolatile

organics,
PAHs
, and chlorinated
pesticides seldom detected


PCBs greater in Puget Sound and at depth


PBDE concentrations relatively high and variable


Most parameters likely exported out of Puget
Sound (cadmium imported)


Sedimentary flux of toxics associated with SPM in
Hood Canal less than in more developed basins


Depth
-
integrated
samples at 3 quarter
points in channel


Surface grabs for
petroleum
-
related
compounds


Concentrations of most detectable
parameters low and similar to other studies


Petroleum
-
related compounds, BNAs and
chlorinated pesticides seldom detected


Organics detected more often in SPM


Some spatial and temporal differences


Most measured daily loads within ranges
estimated from monitoring studies

Summary


Low detection frequency for many organic
compounds in marine and river water


When detected, concentrations of toxics in marine
and river water generally low


Concentrations in Puget Sound often greater than
in ocean boundary waters


Concentrations in deep layers often greater than
in surface layers


Net export of toxic chemicals out of Puget Sound,
except cadmium and lead


Sedimentation and flux of toxic chemicals greater
in basins with more developed watersheds


Concentrations of conventionals, nutrients, and
metals in river water similar to other studies


Marine and river water results improve choice of
input values for the Puget Sound Box Model and
ability to calibrate it


Organic chemicals more likely to be detected in
SPM than in water samples

Summary
(continued)

Recommendations


To improve estimates of external loading:


Sample more intensively near model
boundaries and measure concentrations of
most variable toxics (PBDEs)


Sample more frequently (especially during
storm
-
related flows) and analyze fewer
chemicals


To improve detection frequency of
nonpolar

organic compounds, focus future
sampling on collection/analysis of SPM



Skim through report:

http://www.ecy.wa.gov/biblio/1103008.html

Recommendations

Acknowledgments

Ecology staff:

Bruce Barbour, Julia Bos, Randy Coots, Karin
Feddersen, Mya Keyzers, Stuart Magoon, Jim
Maroncelli, Dean Momohara, Dale Norton, Greg
Pelletier, Brian Pickering, Mindy Roberts, Nancy
Rosenbower, Dave Serdar, Janice Sloan, John
Weakland, Leon Weiks, Jeff Westerlund

Reserved Slides

Parameters Measured


Metals (dissolved and total arsenic, cadmium, copper,
lead, and zinc)


Organic compounds (33 chlorinated pesticides, 55
semivolatile organics, 22 PAHs, 209 PCB congeners, 26
PBDE congeners)


Conventional parameters (total suspended solids,
dissolved and total organic carbon)


Nutrients (nitrogen and phosphorus), hardness, and
petroleum
-
related compounds (TPH and oil and grease)
in river water only




Total PCB Concentrations


Range 6.9
-
75.1 pg/L (mean = 26.3 pg/L)


Puget Sound (30.7 pg/L) > Ocean Boundary (20.4
pg/L)


Ocean boundary < Dangerfield et al, 2007 (42 pg/L)


Deep layer (32.7 pg/L) > surface layer (15.1 pg/L)


Total PBDEs


Detection frequency <25%


Range 50
-
19,000 pg/L (mean = 2900 pg/L)


Measured concentrations highly variable


6/10 detections and two highest concentrations from
ocean boundary sites


Results often

10X greater than Dangerfield et al study

Results: Marine Water Column

Sampling
SPM

from Rivers

River SPM Results


Detection frequency


20% for petroleum
-
related
compounds, semivolatile organics, and chlorinated
pesticides


16 of 22 PAHs measured routinely detected in SPM
with 30
-
210 µg/Kg TPAH (mean = 120 µg/Kg)


Mean PCBs = 410 ng/Kg


Mean PBDEs = 1700 ng/Kg