## Blue Mountain Horticultural Society Annual Meeting

Walla Walla Watershed 2009 Pesticide Monitoring Summary

Kevin Masterson, DEQ

(503) 229-5615 masterson.kevin@deq.state.or.us February 2, 2010 

# Presentation Overview

• Background on Monitoring Program and

Related Activities • 2009 and Historical Monitoring Results

Æ Organophosphate Insecticides • Results from Testing of Expanded List of

Pesticides • Plans for 2010 and Beyond



## Water Monitoring Context: Pesticide Stewardship Partnerships

Using collaborative

partnerships, local expertise and voluntary actions to produce measurable water quality improvements
Everyone’s Goal : General decrease in pesticide

levels in streams over time 

## Pesticide Stewardship Partnership Approach

Monitor for current use pesticides in surface waters from drift & runoff
Identify streams with elevated pesticide concentrations

Collaborate to implement voluntary best management practices

Follow-up monitoring to determine water quality improvements over time



## Walla Walla Project Began in 2005

• Walla Walla Basin Watershed Council – Water sampling, weather stations, outreach • OSU Extension & Blue Mountain Hort Society – Technical assistance, trai ning and implementation • Oregon Department of Environmental Quality – Laboratory analysis, data evaluation & communication • Oregon Department of Agriculture – Technical support • US EPA – Grant funding support 

## Related Stewardship Activities 2006-2009

• Weather Stations • Technical assistance – e.g., March 2007 Spray

Calibration Workshop • Waste Pesticide &

Empty Container Collection Events – 18,000 lbs of pesticides – 6,000 lbs of empty

containers for recycling

## Pesticide Monitoring in Watershed

• Monitoring Locations – 4 mainstem Walla Walla River – 1 on Little WW River in town (at “Frog’) – 4 on “distributaries” in orchard areas • Typical monitoring period Æ late March - June • In 2009 pesticides tested increased from 12 to

over 100 – New ones include herbicides & fungicides with

multiple uses – New lab methods resulted in higher detection limit

for OPs 

# Organophosphate Monitoring

• Chlorpyrifos (Lorsban) and Azinphosmethyl (Guthion) of primary interest – In-Stream Standards at very low levels – Still found in watersheds throughout state 

### • Diazinon and Dimethoate – Detected regularly in previous years – Few recent detections of both in the Walla

Walla watershed

Walla Walla Basin - 2009 Azinphos-Methyl Detections

0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.704/2/094/6/094/10/094/14/094/18/094/22/094/26/094/30/095/4/095/8/095/12/095/16/095/20/095/24/095/28/096/1/096/5/096/9/096/13/096/17/096/21/096/25/09Azinphos-Methyl (ug/L) Little WW River, West Branch/Crockett Little WW River, Midwest Prong W. Prong Little WW River, S. Stateline Rd East Little WW River, N. of Stateline Rd. WQ StandardWalla Walla Watershed: Number of Detections Above Standards/Guidance Values*

2006 2007 2008 2009 Chlorpyrifos (Lorsban) 12 7 7 8

Azinphos-Methyl (Guthion) 14 3 6 10

Diazinon 8 1 10

* Chronic aquatic life values (OAR 340-041-0033) 

## Walla Walla OP Insecticide Monitoring: Summary of 2009 Findings

• Levels of chlorpyrifos (Lorsban) increased in Little

WW distributaries after 2 years of steady declines • Azionphos-methyl (Guthion) still detected multiple

times above standard (0.01 ug/l) in distributaries • Diazinon not detected* & 1 dimethoate detection • No 2009 Walla Walla River detections of OPs

– 3 chlorpyrifos detects in 2008 w/ lower detection limit • 4 low level detections of herbicide Simazine – Can accentuate impacts of OPs

* 2009 lab detection limit higher than in previous years



# New Pesticides Analyzed in 2009

• Over 100 pesticides analyzed • 14 detected in Walla Walla Watershed – 4 from historical suite Æ 3 OPs + Simazine – 10 from new analytical suite 

### • No water quality standards exist the 10

newly analyzed pesticides detected • Multiple registered uses for 10 new ones – Many likely not originating from fruit orchards 

## Detections of New 2009 Pesticides in Walla Walla Watersheds

Insecticides

• Endosulfan sulfate (breakdown product): – 1 detection = 0.032 ug/l – Little WW River, West Branch/Crockett

• Carbaryl : – 13 detections, Max = 0.135 ug/l – All in various Little WW Distributaries

• Imadicloprid : – 1 detection = 0.040 ug/l – Little WW River, West Branch/Crockett



## Detections of New 2009 Pesticides in Walla Walla Watersheds

Herbicides

• Diuron – 46 detections, max = 1.26 ug/l – 2 at WW River at Pepper’s Br. & remainder in distributaries

• Bromacil – 1 detection = 0.038 ug/l – E. Little WW River, N. Stateline Rd.

• Terbacil – 2 detections, max = 0.077 ug/l – Little WW River, West Branch/Crockett

• Dacthal – 1 detection = 0.025 ug/l at WW River, Grove School 

## Detections of New 2009 Pesticides in Walla Walla Watersheds

Fungicides

• Propiconazole – 2 detections, max = 0.070 ug/l – Little WW River at West Branch/Crockett

• Pyraclostrobin – 9 detections, max = 0.019 ug/l – Little WW River distributaries Miscellaneous

• DEET – 4 detections, Max = 0.064 ug/l – All in Little WW Distributaries

# Summary of “New” Pesticide Findings in Walla Walla

• Results provide a baseline for future monitoring • EPA Office of Pesticide Benchmarks can be

used as general screening levels – 2009 results all below draft benchmarks – Inter-agency state team (ODA, DEQ, ODF, State Health) also assessing benchmarks • Unknown issue Æ additive and synergistic

effects of multiple chemicals in water 

## Possible future Partnership Actions: 2010 and Beyond

• Maintain most of existing monitoring network to

track improvements • Consider moving one or two monitoring sites to

other areas in the watersheds (i.e. other land uses) • New pesticide stewardship training and assistance

opportunities ...? • Identify funding for additional waste pesticide

collections • Others?