Central CaliforniaASBS Program

Annual ReportMay 13, 2015

Questions1. Are there spatial patterns in contaminants or

exceedances among reference sites or ASBS discharges?

2. How do exceedances compare to reference values?

3. Are exceedances caused by regulated stormwater discharges?

4. Are there patterns among discharge constituents that could inform choices about management practices?

Organized by Contaminant1. Trace metals

2. Polynuclear aromatic hydrocarbons (PAHs)

3. Pesticides – organophosphate pesticides and pyrethroids

4. Bivalve bioaccumulation – chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and acid-positive pharmaceuticals

5. Toxicity – bivalve larval development, urchin fertilization and kelp germination and growth

6. Fecal indicator bacteria (FIBs), nutrients and total suspended solids (TSS)

Trace Metals1. North-south gradients and consistent

correlations among traces suggest natural effects on trace metal concentrations

2. Concentrations of some trace metals did not different among sample types

3. Pre-storm to storm differences in concentration of only 4 trace metals exhibited significant associations with loads.

Patterns of Exceedances

Patterns of Exceedances

Patterns of ExceedancesDuxbury Reef: Only 5 of 17 exceedances were not

preceded by a pre-storm exceedance (Hg = 1/3)Greater discharge concentrations of As, Ni, Se

Pacific Grove: 33 out of 38 exceedances were not preceded by an pre-storm exceedance (Hg = 4/6)Greater discharge concentrations of Cu, Hg, Pb and

Zn

HgBy ASBS

Pre-storm samples: Duxbury Reef > Carmel Bay

Storm samples: No differences among ASBS

Stormwater discharges: No differences among ASBS

By Reference Region

All regions equal

By Sample Type

Storm > Reference = Pre-storm = Background

SourcesTrace metals wash off the land during storms

They can also be resuspended from bottom sediments during storms

SourcesTrace metals wash off the land during storms

They can also be resuspended from bottom sediments during storms

Metal-Metal CorrelationsDischarges: Hg-Pb, Hg & Pb-TSS, no Cu or Zn

Pre-storm: Hg-Pb, Hg-Cu, Pb-Cu, All 3-TSS, no Zn

Storm: Hg-Pb, Hg-Cu, Hg-Zn, Pb-Zn, Pb-Cu, No TSS

Background: Hg-Pb, Hg-Zn, Pb-Zn All 3-TSS

Hg and Pb travel together, usually with TSS

Hg versus Pb

Hg versus Zn

Hg versus Cu

Trace Metal Loads3 methods: Load/storm, Load/acre, Change in

receiving water concentration

Most of the highest values occurred in Pacific Grove and Carmel Bay

Only 4 trace metals had significant correlations between load and changes in receiving water concentrationAs-, Hg+, Pb+, Zn+

Sediment load reductions = Hg and Pb reductions

Source controls = Zn and Cu reductions

85th Percentile ComplianceWhat is waste? Many metals exhibited patterns

consistent with natural sources.

Consideration of pre-storm exceedances? Use-attainability studies may necessary.

What if natural sources prevent reductions below 85th percentile? There were no exceedances of Ocean Plan Instantaneous Maximum.

PAHs and PesticidesNone detected at quantifiable concentrations at

references sites

PAHs and PesticidesNone detected at quantifiable concentrations at

references sites Automatic exceedance for any detection in storm water

Patterns of Exceedance

pyrethroids and organophosphate pesticides were rarely detected

PAHs

PAHs in 7 samples exceeded Ocean Plan 30-day average objective

CorrelationsPAHs and summed Pyrethroids significantly

correlated with TSSLoad reductions possible through

sediment/TSS management

Compliance IssuesNo Ocean Plan Instantaneous Maximum for PAHs

PAH concentrations measured from grab samples do not accurately reflect actual ocean concentrations

No Ocean Plan objectives for pyrethroids or organophosphorous pesticides

BioaccumulationCollaboration with CCLEAN

6 sites, including Carmel Bay and Point Reyes

Mussels from Carmel River Beach has had among the lowest concentrations of measured organic pollutants over 13 years.

Some sites have exceeded human health alert levels, mostly in northern Monterey Bay

Acid-positive pharmaceuticals detected at every site, mostly from livestock or petsCaffeine highest concentration detected at The

Hook

Pollutants trending downward

ToxicityASBS samples rarely failed any of four tests

Toxicity rarely found at reference sites

Patterns of Toxicity

Several discharge samples and their corresponding receiving water samples from Pacific Grove and Carmel failed the urchin toxicity test during the February 2014 storm

Toxicity ComplianceHigh Cu and Zn concentrations in the failed

discharge and storm samples could be partly responsible

Neither Cu nor Zn can be controlled by reducing sediment loads

Nutrients, TSS and FIBsRare detection of ammonia and orthophosphate

= exceedances for any detection in storm samples

Urea was broadly detected, including at reference sites

Patterns in Nutrients, TSS & FIBs

Highest concentrations of all constituents occurred in ASBS storm samples

Differences rarely significant by ANOVA but ANOVA insignificance often contradicted by non-parametric test (6/8 significant)

ASBS storm concentrations of E. coli linearly associated with discharge concentrations

High nutrient concentrations in ASBS storm water could be due to resuspension during storms

General ConsiderationsEffects of meteorology and logistics

During very large storms some reference sites are inaccessible

Reduced range in reference values, especially for the storms most likely to have very high runoff

Large storm in December 2014No sampling along Big Sur coastVery high Hg concentrations at 2 northern reference

sitesIf include, Hg 85th percentile goes from 0.74 ng/L to

2.8 ng/L

General Considerations

Effects of natural processes on trace metal concentrations suggest more work needed before compliance should be enforced

Consideration recommended for exceedances in pre-storm samples

General consistency between ASBS storm samples and Background samples suggest area wide patterns in nearshore water quality

Priority for compliance should be on determining sources of and reductions in toxicity