Year 1 Monitoring Report Diazinon and Pesticide-Related Toxicity

OCTOBER 2016

MARIN COUNTY STORMWATER POLLUTION PREVENTION PROGRAM AND CITY OF PETALUMA

Year 1 Monitoring Report

Diazinon and Pesticide-Related Toxicity TMDL Monitoring Program in Urban Creeks submitted to SAN FRANCISCO BAY REGIONAL WATER QUALITY CONTROL BOARD prepared by LARRY WALKER ASSOCIATES

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Table of Contents 1. Introduction ...... 1 2. Monitoring Methods, Stations, and Parameters ...... 2 2.1. Monitoring Stations ...... 2 2.2. Monitoring Events ...... 2 2.3. Monitoring Constituents ...... 4 2.4. Stream Flow Analysis ...... 4 2.5. Analytical Methods ...... 5 3. Event Summaries ...... 7 3.1. Event 1: January 5, 2016 ...... 7 3.2. Event 2: March 5, 2016 ...... 9 3.3. Event 3: June 9, 2016 ...... 12 4. Data Summary and Recommendations ...... 15 4.1. Water Quality Measurements ...... 15 4.2. Stage Height and Surface Water Velocity ...... 15 4.3. Conventional Parameters ...... 16 4.4. Pesticides...... 16 4.5. Recommendations for 2016-2017 ...... 19

Attachments: Attachment A: Applied Marine Sciences Event 1 Field Report, Field Data Sheets, and Chain of Custody Forms Attachment B: Applied Marine Sciences Event 2 Field Report, Field Data Sheets, and Chain of Custody Forms Attachment C: Applied Marine Sciences Event 3 Field Report, Field Data Sheets, and Chain of Custody Forms

MCSTOPPP and City of Petaluma i October2016 2015-2016 Urban Creek Monitoring Report List of Tables Table 1. Proposed Pesticide Monitoring Locations ...... 2 Table 2. Monitoring Constituents ...... 4 Table 3. Stream Flow Data Sources ...... 5 Table 4. Parameters Monitored in 2015-2016 ...... 6 Table 5. Event 1 Quality Control Samples ...... 7 Table 6. Event 1 Results – January 5, 2016 ...... 8 Table 7. Event 1 Flow at Marin County Urban Creek Sites – January 5, 2016 ...... 9 Table 8. Event 2 Quality Control Samples ...... 9 Table 9. Event 2 Results – March 5, 2016 ...... 11 Table 10. Event 2 Flow at Marin County Urban Creek Sites – March 5, 2016 ...... 12 Table 11. Event 3 Quality Control Samples ...... 12 Table 12. Event 3 Results – June 9, 2016 ...... 13 Table 13. Event 3 Flow at Marin County Urban Creek Sites – June 9th, 2016 ...... 14 Table 14. General Water Quality Parameters ...... 15 Table 15. Stage Height and Surface Water Velocity ...... 16 Table 16. Summary Statistics for Pesticide Results in East Marin Creeks and Petaluma River (ng/L) ...... 17 Table 17. Pesticide Water Quality Thresholds and Comparison with Year 1 Results ...... 18

List of Figures Figure 1. Monitoring Stations and Surrounding Watersheds...... 3

MCSTOPPP and City of Petaluma ii October2016 2015-2016 Urban Creek Monitoring Report 1. Introduction The Marin County Stormwater Pollution Prevention Program (MCSTOPPP) agencies as well as the City of Petaluma (Petaluma) are subject to the Municipal Separate Stormwater Sewer System (MS4) Phase II General Permit (Phase II Permit).1 MCSTOPPP and Petaluma are conducting regional monitoring efforts to satisfy Phase II Permit monitoring requirements for all MCSTOPPP member agencies and Petaluma. MCSTOPPP consists of the individual cities within Marin County and the unincorporated County areas. MCSTOPPP and Petaluma must comply with the 2005 Diazinon and Pesticide-Related Toxicity in Urban Creeks Total Maximum Daily Load (TMDL) monitoring requirements as described in Attachment G of the Phase II Permit: Monitor water and sediment for pesticides and associated toxicity in urban creeks via an individual or regional program designed to answer the following questions: 1) Are the TMDL toxicity targets being met? Is toxicity observed in urban creeks caused by a pesticide? 2) Is urban runoff the source of any observed toxicity in urban creeks? 3) How does observed pesticide-related toxicity in urban creeks (or pesticide concentrations contributing to such toxicity) vary in time and magnitude across urban creek watersheds, and what types of pest control practices contribute to such toxicity? 4) Are actions already being taken to reduce pesticide discharges sufficient to meet the targets, and if not, what should be done differently? All monitoring activities are conducted in accordance with the August 2015 MCSTOPPP and City of Petaluma Monitoring Plan and Quality Assurance Project Plan: Diazinon and Pesticide- Related Toxicity TMDL Monitoring Program in Urban Creeks (QAPP), unless otherwise noted in this report. The QAPP outlines the management aspects of the monitoring program, the design of the sampling process, the sample collection and handling processes, the analytical methods, the quality control, and the data management, validation, and review. The program aims to characterize pesticide concentrations and other water quality parameters during wet and dry season conditions in East Marin County creeks and the Petaluma River. This report describes the monitoring stations, methods used for sample collection and analysis, field activities conducted during the monitoring events, and the results of field and laboratory measurements produced during sampling season 2015-2016, the first year of a minimum two- year monitoring effort. The report relies on findings gathered by Applied Marine Sciences (AMS), the MCSTOPPP and Petaluma contractor for the sampling project. AMS produced field reports for each monitoring event (see Attachment A through C).

1www.waterboards.ca.gov/water_issues/programs/stormwater/docs/phsii2012_5th/order_final.pdf

MCSTOPPP and City of Petaluma 1 October 2016 2015-2016 Urban Creek Monitoring Report 2. Monitoring Methods, Stations, and Parameters Monitoring stations and methods used during the 2015-2016 monitoring program are summarized in this section. Field services in 2015-2016 were provided by AMS for MCSTOPPP while Petaluma used in-house staff.

2.1. MONITORING STATIONS Water quality samples were collected at locations in Novato Creek, San Rafael Creek, Ross Valley, Arroyo Corte Madera del Presidio, and Petaluma River watersheds. The stations are located downstream of urban areas at locations that can be safely accessed during storm runoff events. Along the Petaluma River, samples were also collected at a site upstream of most urban development in the area (PET310). Table 1 shows the monitoring stations and naming conventions. A map of the stations is provided in Figure 1. Characteristics of the tributary watersheds have been previously detailed in the QAPP.

Table 1. Proposed Pesticide Monitoring Locations

Creek Station Name Location ID Latitude Longitude Novato Creek Lee Gerner Park 206NOV160 38.1070 -122.5786 Arroyo Corte Madera Del Presidio La Goma Bridge 203ACM070 37.8976 -122.5350 Corte Madera Creek Lagunitas Road Bridge 203COR060 37.9632 -122.5571 San Rafael Creek D Street Overcrossing 203SNR180 37.9706 -122.5325 Petaluma River, Upstream Outlet Mall PET310 38.2558 -122.6515 Petaluma River, Downstream 500ft upstream of Ellis Creek PETC2A 38.2091 -122.5819 Recycled Water Facility outfall

2.2. MONITORING EVENTS East Marin County urban creeks (East Marin creeks) and the Petaluma River were monitored for general water quality characteristics and pesticide concentrations. The Petaluma River is heavily influenced by tides up to its confluence with Lynch Creek (past the railroad tracks); monitoring windows targeted lower tide intervals that would allow Petaluma crews access to the river sampling sites. The QAPP calls for collecting and analyzing water samples from three storm events and one dry weather event each monitoring season. However, due to a shortage of precipitation events that met mobilization criteria, only two wet weather events were sampled in Year 1: on January 5, 2016 and March 5, 2016. The dry season sampling was conducted on June 9, 2016.

MCSTOPPP and City of Petaluma 2 October 2016 2015-2016 Urban Creek Monitoring Report

Figure 1. Monitoring Stations and Surrounding Watersheds

MCSTOPPP and City of Petaluma 3 October 2016 2015-2016 Urban Creek Monitoring Report 2.3. MONITORING CONSTITUENTS All water samples were collected by direct immersion of sample bottles either by-hand or with a fiberglass extension pole (i.e. “grab” samples). Grab samples were assessed for the constituents listed in Table 2. Immediately prior to sample collection, handheld water quality meters were used to determine in-situ measurements of water temperature, pH, and dissolved oxygen concentration. Conductivity was also measured in the field for the East Marin creek samples; it was measured in the lab for the Petaluma River samples.

Table 2. Monitoring Constituents Pesticides Conventional Parameters Field Parameters Chlorpyrifos Total Organic Carbon Water Temperature Diazinon Dissolved Organic Carbon pH Allethrin Suspended Sediment Concentration Electrical Conductivity Bifenthrin Total Dissolved Solids Dissolved Oxygen Cyfluthrin Turbidity Lambda-Cyhalothrin Cypermethrin Deltamethrin:Tralomethrin Esfenvalerate:Fenvalerate Fenpropathrin Fipronil Fipronil desulfinyl Fipronil sulfide Fipronil sulfone Tau-Fluvalinate Permethrin Tetramethrin

2.4. STREAM FLOW ANALYSIS Stream flow was determined for each sampling event and location to assess the influence of urban runoff on the collected samples. Existing stream gauges are present at three of the monitored sites: Novato Creek, Corte Madera Creek, and Petaluma River. The QAPP also specifies a stream gauge at Arroyo Corte Madera (Marin Co. Station 5251) but following the first monitoring event, it was determined that there is no flow sensor associated with the stream gauge at this location. In subsequent sampling events, field crews estimated flows using channel geometry and surface velocity. Table 3 lists the stream gauges used in the course of the study and the web address where they can be accessed. To complement the gauged data, stream flow assessments were performed at San Rafael Creek and Arroyo Corte Madera, employing two methods: 1) manual stream rating per USGS methodology for wadeable conditions, and 2) cross-sectional area multiplied by surface velocity for non-wadeable conditions.

MCSTOPPP and City of Petaluma 4 October 2016 2015-2016 Urban Creek Monitoring Report Table 3. Stream Flow Data Sources Station Stream Gauge Data source 203COR060 Marin Co station 5255 https://marin.onerain.com/stage.php 203ACM070 Marin Co station 5251(1) https://marin.onerain.com/stage.php 206NOV160 USGS 11459500 http://nwis.waterdata.usgs.gov/ca/nwis/ PET310, PETC2A USGS station 11459150 http://nwis.waterdata.usgs.gov/ca/nwis/ (1) Flow sensor not available at station; only stage height available.

2.5. ANALYTICAL METHODS Aside from turbidity, which was analyzed by the City of Petaluma in-house lab, the water quality parameters in Table 2 were analyzed by Caltest Analytical Laboratory (Caltest) of Napa. For each measurement performed, the units, analytical method, reporting limit (RL), and method detection limit (MDL)—if applicable, are presented in Table 4.

MCSTOPPP and City of Petaluma 5 October 2016 2015-2016 Urban Creek Monitoring Report Table 4. Parameters Monitored in 2015-2016 Parameter Units MDL RL Analytical Method Conventionals Suspended Sediment Concentration mg/L 2 3 ASTMD 3977-97 Total Dissolved Solids mg/L 4 10 SM 2540C Turbidity NTU 0.1 0.1 SM 2130B Temperature ºC -- 0.1 Field Electrical Conductivity µs/cm -- 1 Field Total Organic Carbon mg/L 0.3 1 SM 5310B Dissolved Organic Carbon mg/L 0.3 1 SM 5310B Pesticides Allethrin ng/L 0.1 0.5 EPA 8270M-NCI Bifenthrin ng/L 0.1 0.5 EPA 8270M-NCI Cyfluthrin ng/L 0.2 1 EPA 8270M-NCI Lambda-Cyhalothrin ng/L 0.2 0.5 EPA 8270M-NCI Cypermethrin ng/L 0.2 0.5 EPA 8270M-NCI Deltamethrin:Tralomethrin ng/L 0.2 1 EPA 8270M-NCI Esfenvalerate:Fenvalerate ng/L 0.2 1 EPA 8270M-NCI Fenpropathrin ng/L 0.2 0.5 EPA 8270M-NCI Fipronil ng/L 0.5 1 EPA 8270M-NCI Fipronil Desulfinyl ng/L 0.5 1 EPA 8270M-NCI Fipronil Sulfide ng/L 0.5 1 EPA 8270M-NCI Fipronil Sulfone ng/L 0.5 1 EPA 8270M-NCI Tau-Fluvalinate ng/L 0.2 0.5 EPA 8270M-NCI Permethrin ng/L 2 10 EPA 8270M-NCI Tetramethrin ng/L 0.2 0.5 EPA 8270M-NCI Chlorpyrifos ng/L 0.5 1 EPA 8270M-NCI Diazinon ng/L 0.1 0.5 EPA 8270M-NCI

MCSTOPPP and City of Petaluma 6 October 2016 2015-2016 Urban Creek Monitoring Report 3. Event Summaries During the 2015-2016 monitoring season, two wet weather events were sampled on January 5, 2016 and March 5, 2016, and a dry sampling was conducted on June 9, 2016. The monitoring activities and results for each event are described in the following sections. Field monitoring reports are attached.

3.1. EVENT 1: JANUARY 5, 2016

3.1.1. Sampling Activities As detailed in the AMS Event 1 Field Report (Attachment A), sampling of all sites was successfully completed between 10:00 and 14:26 on January 5, 2016. Approximately two inches of rainfall were recorded during the twenty hours preceding water sample collection. Rainfall continued throughout the daylight hours of sampling, but at generally reduced intensity. Samples were delivered to the City of Petaluma (turbidity) and Caltest (all others) on the same day.

3.1.2. QA/QC Measures Quality assurance for the collected samples was performed through QA/QC samples collected per the Project QAPP specifications. The quality control samples are summarized in Table 5.

Table 5. Event 1 Quality Control Samples Analyte Equipment Blank Field Blank Field Duplicate MS/ MSD Pesticides 203ACM070 206NOV160 206NOV160 Suspended Sediment 206NOV160 TDS 206NOV160 TOC X 203ACM070 206NOV160 DOC 206NOV160 Turbidity 203ACM070 206NOV160 Note: The Flied Blank, Field Duplicate, and MS/ MSD columns specify the respective station for these samples. The Equipment Blank column uses “X” to indicate the analytes for which this type of QA sample was used.

Monitoring results were validated against measurements quality objectives (MQO) specified in the QAPP for sensitivity, lab blanks, accuracy, field blanks, field duplicates, and equipment blanks. There were no qualifiers needed for Event 1 results with respect to any of these MQOs. The only potential issue identified was the equipment blank (EB) sample that was collected and analyzed for TOC, the sole analysis for which a transfer container is employed in sample collection. The result of this analysis was reported slightly above RL (1.3 mg/L vs. 1 mg/L). The final TOC results were not qualified for two reasons: 1) results for field samples were not less than 5 times higher than EB results, consistent with QAPP quality control data validation; and 2) the results of the Field Blank sample collected associated with this event was below RL.

MCSTOPPP and City of Petaluma 7 October 2016 2015-2016 Urban Creek Monitoring Report 3.1.3. Water Quality Results The field and laboratory results for Event 1are shown in Table 6 below. Non-detect results are shown as ‘less than’ the respective MDL. Detected but no quantified (DNQ) results (above the MDL but below the RL) are qualified with a “J” in front of the reported value.

Table 6. Event 1 Results – January 5, 2016 Parameter Units 203ACM070 203COR060 203SNR180 206NOV160 PET310 PETC2A Field Measurements Temperature ºC 11.3 10.7 12.0 10.9 12.3 12.3 Electrical Conductivity µs/cm 132 131 229 187 462 9687 pH -- 7.6 7.8 7.5 7.7 7.2 7.7 Dissolved Oxygen mg/L 11.6 12.4 12.0 11.4 8.5 9.0 Conventionals Suspended Sediment mg/L 50 86 10 55 23 30 Total Dissolved Solids mg/L 120 130 190 190 340 7200 Turbidity NTU 28 47 14 51 24 24 Total Organic Carbon mg/L 7.1 8.9 12 13 10 8.1 Dissolved Organic 6.8 8.9 12 13 10 8.2 mg/L Carbon Pesticides Allethrin ng/L <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 Bifenthrin ng/L 0.7 0.8 J0.3 J0.3 <0.1 <0.1 Cyfluthrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Lambda-Cyhalothrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Cypermethrin ng/L <0.2 J0.4 <0.2 <0.2 <0.2 <0.2 Deltamethrin:Tralomethri <0.2 <0.2 <0.2 ng/L <0.2 <0.2 <0.2 n Esfenvalerate:Fenvalera <0.2 J0.3 <0.2 ng/L <0.2 <0.2 <0.2 te Fenpropathrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Fipronil ng/L 13 17 31 17 2.6 6.4 Fipronil Desulfinyl ng/L <0.5 <0.5 J0.7 1.1 J0.8 1.8 Fipronil Sulfide ng/L J0.8 J0.7 2.5 1.3 <0.5 J0.7 Fipronil Sulfone ng/L 7.4 6.4 23 13 2.4 5 Tau-Fluvalinate ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Permethrin ng/L J6.3 <0.2 <0.2 <0.2 <0.2 <0.2 Tetramethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Chlorpyrifos ng/L 6.6 J0.6 <0.5 <0.5 <0.5 <0.5 Diazinon ng/L <0.1 <0.1 <0.1 <0.1 <0.1 <0.1

MCSTOPPP and City of Petaluma 8 October 2016 2015-2016 Urban Creek Monitoring Report 3.1.4. Flow Determination

Water depth and flow, shown in Table 7 below, were determined based on measurements in the field or using online data sources for existing gauges at the sampling locations (See Section 2.4).

Table 7. Event 1 Flow at Marin County Urban Creek Sites – January 5, 2016 Station Sampling Time Data source Stage Height (ft) Flow (ft3/sec) 203ACM070 14:00 Marin Co station 5251(1) 3.81 Not measured 203COR060 10:10 Marin Co station 5255 9.91 376 206NOV160 11:40 USGS 11459500 3.92 51 203SNR180 13:00 Field estimated 0.50 22 PET310 10:30 USGS 11459150 4.92 65 PETC2A 15:25 USGS 11459150 0.31 213 (1) Flow sensor not available at station; only stage height available (see Section 2.4).

3.2. EVENT 2: MARCH 5, 2016

3.2.1. Sampling Activities As detailed in the AMS Event 2 Field Report (Attachment B), sampling of all sites was successfully completed between 11:35 and 16:34 on March 5, 2016. Approximately half an inch of rain was recorded during the eleven hours preceding sample collection. Samples were delivered to the City of Petaluma (turbidity) and Caltest (all others) on the same day.

3.2.2. QA/QC Measures Quality assurance for the collected samples was performed through QA/QC samples collected per the Project QAPP specifications. The quality control samples are summarized in Table 8.

Table 8. Event 2 Quality Control Samples Analyte Equipment Blank Field Blank Field Duplicate MS/ MSD Pesticides PETC2A PETC2A TOC X PETC2A PETC2A DOC X PETC2A Turbidity PETC2A Note: The Field Blank, Field Duplicate, and MS/ MSD columns specify the respective station for these samples. The Equipment Blank column uses “X” to indicate the analytes for which this type of QA sample was used.

Monitoring results were validated against MQOs specified in the QAPP for sensitivity, lab blanks, accuracy, field blanks, field duplicates, and equipment blanks. The only qualifier needed for Event 2 results was for analysis of DOC and TOC in Petaluma River samples which had recovery percentage of 74% and 77%, respectively, outside of the 80% to 120% range specified in the QAPP. Consequently, these QA samples were flagged by Caltest. Another potential issue is related to one non-detect suspended sediment concentration (SSC) result. Due to a change in

MCSTOPPP and City of Petaluma 9 October 2016 2015-2016 Urban Creek Monitoring Report lab capabilities, the SSC RL was 3 mg/L, above the QAPP target of 2 mg/L. As such, this non- detect was flagged as out of compliance with the MQOs; however, at 2 mg/L the analytical MDL was low and the RL value is not a critical issue.

3.2.3. Water Quality Results The field and laboratory results for Event 2 are shown in Table 9. Non-detect results are shown as ‘less than’ the respective MDL. DNQ results (above the MDL but below the RL) are qualified with a “J” in front of the reported value.

MCSTOPPP and City of Petaluma 10 October 2016 2015-2016 Urban Creek Monitoring Report Table 9. Event 2 Results – March 5, 2016 Parameter Units 203ACM070 203COR060 203SNR180 206NOV160 PET310 PETC2A Field Measurements Temperature ºC 14.3 15.1 15.7 15.6 15.8 16.6 Electrical Conductivity µs/cm 158 183 278 298 839 814 pH -- 7.5 7.5 7.6 7.8 7.6 7.8 Dissolved Oxygen mg/L 13.1 14.5 14.5 13.9 5.6 7.6 Conventionals Suspended Sediment mg/L 7.4 21 3.7 <2(1) 4.9 31 Total Dissolved Solids mg/L 110 120 200 190 530 4,900 Turbidity NTU 10.9 17.8 12.5 2.8 7.14 24.3 Total Organic Carbon mg/L 5 6.3 10 4.7 12(2) 12(2) Dissolved Organic Carbon mg/L 4.4 4.6 8.9 4.5 11(3) 12(3) Pesticides Allethrin ng/L <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 Bifenthrin ng/L J0.4 0.6 <0.1 J0.3 <0.1 <0.1 Cyfluthrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Lambda-Cyhalothrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Cypermethrin ng/L <0.2 J0.4 J0.3 <0.2 <0.2 <0.2 Deltamethrin:Tralomethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Esfenvalerate:Fenvalerate ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Fenpropathrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Fipronil ng/L 28 19 19 13 J0.9 1.1 Fipronil Desulfinyl ng/L J0.8 1.3 J0.7 1.5 J0.6 1.5 Fipronil Sulfide ng/L J0.9 1.3 2.3 1.5 <0.5 J0.6 Fipronil Sulfone ng/L 7.6 11 21 12 1.4 1.6 Tau-Fluvalinate ng/L <0.2 <0.2 J0.3 <0.2 <0.2 <0.2 Permethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Tetramethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Chlorpyrifos ng/L <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 Diazinon ng/L <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 QA/QC notes: (1) Due to a change in lab capabilities, the RL was 3 mg/L, above the QAPP target of 2 mg/L. As such, the result is flagged as out of compliance with the MQOs; however, at 2 mg/L the analytical MDL was low and the RL value is not a critical issue. (2) Recovery percentage of 74% is outside of the 80% to 120% range specified in the QAPP. (3) Recovery percentage of 77% is outside of the 80% to 120% range specified in the QAPP.

3.2.4. Flow Determination

Water depth and flow, shown in Table 10 below, were determined based on measurements in the field or using online data sources for existing gauges at the sampling locations (See Section 2.4).

MCSTOPPP and City of Petaluma 11 October 2016 2015-2016 Urban Creek Monitoring Report Table 10. Event 2 Flow at Marin County Urban Creek Sites – March 5, 2016 Station Sampling Time Data source Stage Height (ft) Flow (ft3/sec) 203ACM070 11:35 Marin Co station 5251(1) 3.39 40 203COR060 12:35 Marin Co station 5255 7.61 99 206NOV160 14:05 USGS 11459500 3.05 2.5 203SNR180 13:15 Field estimated 0.67 9 PET310 14:50 USGS 11459150 -1.03 162 PETC2A 16:34 USGS 11459150 -0.27 182 (1) Flow sensor not available at station; only stage height available. Flow is estimated as described in Section 2.4.

3.3. EVENT 3: JUNE 9, 2016

3.3.1. Sampling Activities As detailed in the AMS Event 3 Field Report (Attachment C), sampling of all sites was successfully completed between 10:15 and 15:35 on June 9, 2016. This was a dry season sample; no rain was recorded in the ten-day prior to sampling. Samples were delivered to the City of Petaluma (turbidity) and Caltest (all others) on the same day.

3.3.2. QA/QC Measures Quality assurance for the collected samples was performed through QA/QC samples collected per the Project QAPP specifications. The quality control samples are summarized in Table 11.

Table 11. Event 3 Quality Control Samples Analyte Equipment Blank Field Blank Field Duplicate MS/ MSD Pesticides PETC2A PET310 PETC2A Suspended Sediment PET310 TOC X PETC2A PET310 DOC PET310 TDS PET310 Note: The Field Blank, Field Duplicate, and MS/ MSD columns specify the respective station for these samples. The Equipment Blank column uses “X” to indicate the analytes for which this type of QA sample was used.

Monitoring results were validated against MQOs for sensitivity, lab blanks, accuracy, field blanks, field duplicates, and equipment blanks. The only qualifier needed for Event 3 results was for the SSC results at one of the Petaluma River sites. The relative percent difference (RPD) for the field sample / field duplicate pair at PET310 was 53%, exceeding the QAPP control limit of 25%. Consequently, these samples were flagged as not meeting the QAPP MQO. Another potential issue is related to the four non-detect SSC results recorded during this event. As in Event 2, the SSC RL was 3 mg/L, exceeding the QAPP target of 2 mg/L. The non-detects were flagged as out of compliance with the MQO; however, at 2 mg/L the analytical MDL was low and the RL value is not a critical issue.

MCSTOPPP and City of Petaluma 12 October 2016 2015-2016 Urban Creek Monitoring Report 3.3.3. Water Quality Results The field and laboratory results for Event 3 are shown in Table 12. Non-detect results are shown as ‘less than’ the respective MDL. Detected but no quantified (DNQ) results (above the MDL but below the RL) are qualified with a “J” in front of the reported value.

Table 12. Event 3 Results – June 9, 2016 Parameter Units 203ACM070 203COR060 203SNR180 206NOV160 PET310 PETC2A Field Measurements Temperature ºC 15.9 17.4 17.9 16.8 18.9 21.8 Electrical Conductivity µs/cm 261 415 512 453 1154 23280 pH -- 7.6 7.5 8.1 8.2 7.6 7.6 Dissolved Oxygen mg/L 11.7 10.1 10.8 12.1 5.4 6.6 Conventionals Suspended Sediment mg/L <2(1) <2(1) <2(1) <2(1) 19(2) 14 Total Dissolved Solids mg/L 240 270 220 260 680 15,000 Turbidity NTU 0.45 0.33 2.97 0.82 13.4 4.41 Total Organic Carbon mg/L 3.1 1.8 1.9 2.9 9.2 10 Dissolved Organic Carbon mg/L 3.2 1.7 1.7 1.4 9.1 10 Pesticides Allethrin ng/L <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 Bifenthrin ng/L <0.1 <0.1 J0.2 <0.1 <0.1 <0.1 Cyfluthrin ng/L <0.2 <0.2 J0.3 <0.2 <0.2 <0.2 Lambda-Cyhalothrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Cypermethrin ng/L <0.2 <0.4 0.7 <0.2 <0.2 <0.2 Deltamethrin:Tralomethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Esfenvalerate:Fenvalerate ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Fenpropathrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Fipronil ng/L 1.7 1.9 1.1 1.2 <0.5 <0.5 Fipronil Desulfinyl ng/L <0.5 J0.6 <0.5 <0.5 <0.5 <0.5 Fipronil Sulfide ng/L <0.5 J0.6 1 <0.5 <0.5 <0.5 Fipronil Sulfone ng/L 2.2 3.6 5.4 2.9 J0.6 J0.7 Tau-Fluvalinate ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Permethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Tetramethrin ng/L <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Chlorpyrifos ng/L <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 Diazinon ng/L <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 QA/QC notes: (1) Due to a change in lab capabilities, the RL was 3 mg/L, above the QAPP target of 2 mg/L. As such, the result is flagged as out of compliance with the MQOs; however, at 2 mg/L the analytical MDL was low and the RL value is not a critical issue. (2) The relative percent difference (RPD) for the field sample / field duplicate pair at PET310 was 53%, exceeding the QAPP control limit of 25%.

MCSTOPPP and City of Petaluma 13 October 2016 2015-2016 Urban Creek Monitoring Report 3.3.4. Flow Determination

Water depth and flow, shown in Table 13 below, were determined based on measurements in the field or using online data sources for existing gauges at the sampling locations (see Section 2.4).

Table 13. Event 3 Flow at Marin County Urban Creek Sites – June 9, 2016 Station Sampling Time Data source Stage Height (ft) Flow (ft3/sec) 203ACM070 10:15 Marin Co station 5251(1) 2.90 Insufficient Flow 203COR060 11:35 Marin Co station 5255 6.99 23 206NOV160 13:40 USGS 11459500 2.97 1.2 203SNR180 12:15 Field estimated 0.10 Insufficient flow PET310 15:35 USGS 11459150 -0.32 -105 PETC2A 13:15 USGS 11459150 -3.07 9 (1) Flow sensor not available at station; only stage height available. Flow is estimated as described in Section 2.4.

MCSTOPPP and City of Petaluma 14 October 2016 2015-2016 Urban Creek Monitoring Report 4. Data Summary and Recommendations A summary of results for each set of monitored constituents is provided below. There are insufficient data after one year to assess trends or impacts, and observations are provided only to identify patterns to evaluate further when additional data are available.

4.1. WATER QUALITY MEASUREMENTS Four water quality parameters (temperature, conductivity, pH, and DO) were measured immediately prior to water sample collection at each East Marin site and three parameters measured (temperature, pH, and DO) at the Petaluma River sites. Conductivity for Petaluma River samples was subsequently measured in the lab. Measurement results from all three events are summarized in Table 14. As expected, water temperature was coldest at each of the monitoring sites in January, and increased by at least 4˚C by the June sampling. As with temperatures, the specific conductivity increased steadily among the successive events. All recorded values were typical of ambient conditions in freshwater streams, which usually range from 100-500 µS/cm. pH did not vary greatly at the majority of sampling events at either East Marin or Petaluma sites. The East Marin creek sites corresponded to higher DO concentrations during the March sampling event relative to either the January or June events. The Petaluma sites both exhibited lower DO at each successive sampling event, attaining the lowest DO values among all sites in June. Notably, the downstream location (PETC2A) exhibited higher DO than the upstream location (PET310) at each of the sampling events. DO concentrations at all East Marin creek sites met the WQO for DO (7.0 mg/L). Measurements taken at PET310 sites in March and June, and at PETC2A in June were outside this objective, however.

Table 14. General Water Quality Parameters Temperature Conductivity Dissolved Oxygen (˚C) (µS/cm) pH (mg/L) Events Events Events Events Station 1 2 3 1 2 3 1 2 3 1 2 3 203ACM070 11.3 14.3 15.9 132 158 261 7.6 7.5 7.6 11.6 13.1 11.7 203COR060 10.7 15.1 17.4 131 183 415 7.8 7.5 7.5 12.4 14.5 10.1 203SNR180 12.0 15.7 17.9 229 278 512 7.5 7.6 8.1 12.0 14.5 10.8 206NOV160 10.9 15.6 16.8 187 298 453 7.7 7.8 8.2 11.4 13.9 12.1 PET310 12.3 15.8 18.9 462 839 1154 7.2 7.6 7.6 8.5 5.6 5.4 PETC2A 12.3 16.6 21.8 9687 814 23280 7.7 7.8 7.6 9.0 7.6 6.6

4.2. STAGE HEIGHT AND SURFACE WATER VELOCITY Surface velocity and water depth were determined for each event/location based on direct measurements in the field or using online data sources for existing staff gauges at the sampling locations. All sites were deepest and had the highest flow rates during the January sampling event. Both variables were considerably reduced at each successive event, attaining flow levels

MCSTOPPP and City of Petaluma 15 October 2016 2015-2016 Urban Creek Monitoring Report in June that were too low for estimation at the two East Marin sites without flow sensing staff gauges (203ACM070 and 203SNR180).

Table 15. Stage Height and Surface Water Velocity Gauge Height (ft) Velocity (ft3 per sec) Station Event 1 Event 2 Event 3 Event 1 Event 2 Event 3 203ACM070 3.81 3.39 2.90 Not measured 40 Insufficient flow 203COR060 9.91 7.61 6.99 376 99 23 203SNR180 0.50 0.67 0.10 22 9 Insufficient flow 206NOV160 3.92 3.05 2.97 51 2.5 1.2 PET310 4.92 1.03 -0.32 65 162 -105 PETC2A 0.31 -0.27 -3.07 213 182 9

4.3. CONVENTIONAL PARAMETERS Dissolved Organic Carbon (DOC) and Total Organic Carbon (TOC)

DOC and TOC were closely correlated at the majority of sampling locations with results ranged from 5 mg/L to 13 mg/L. Concentrations were higher in the wet season versus the dry season, especially for the East Marin creeks. Suspended Sediment Concentration (SSC) SSC varied between non-detect and 86 mg/L for the East Marin creek stations, with the highest ranges in January and lowest in June. SSC values at the Petaluma River sites ranged between 4.9 mg/L and 31 mg/L and did not exhibit as much variability between the wet and dry seasons. Total Dissolved Solids (TDS) TDS generally varied between 110 mg/L and 680 mg/L with one notable exception: PETC2A (Petaluma River downstream) with TDS values an order of magnitude outside this range. The highest TDS values from East Marin creeks were during the dry season. Turbidity Turbidity values ranged from below 1 NTU to 62 NTUs and decreases from the January to June sampling events.

4.4. PESTICIDES Summary statistics for all pesticide monitoring results are presented in Table 16. Results indicate that most concentrations were below the MDL or RL. Pesticides with at least one sample above the RL were chlorpyrifos, cypermethrin, bifenthrin, fipronil and all fipronil degradates. A more comprehensive analysis, including a breakdown of wet vs dry season, will be performed at the end of Year 2 when more data are available.

MCSTOPPP and City of Petaluma 16 October 2016 2015-2016 Urban Creek Monitoring Report Table 16. Summary Statistics for Pesticide Results in East Marin Creeks and Petaluma River (ng/L) Parameter Count Detected Min Max Ave Chlorpyrifos 18 2 <0.5 6.6 ID Diazinon 18 0 <0.1 <0.1 ND Allethrin 18 0 <0.1 <0.1 ND Bifenthrin 18 8 <0.1 0.8 0.26 Cyfluthrin 18 2 <0.2 J0.3 ID Lambda-Cyhalothrin 18 0 <0.2 <0.2 ND Cypermethrin 18 4 <0.2 0.7 0.18 Deltamethrin:Tralomethrin 18 0 <0.2 <0.2 ND Esfenvalerate:Fenvalerate 18 1 <0.2 J0.3 ID Fenpropathrin 18 0 <0.2 <0.2 ND Fipronil 18 16 <0.5 31 9.69 Fipronil Desulfinyl 18 11 <0.5 1.8 0.77 Fipronil Sulfide 18 12 <0.5 2.5 0.89 Fipronil Sulfone 18 18 J0.6 23 7.07 Tau-Fluvalinate 18 1 <0.2 J0.3 ID Permethrin 18 1 <2 J6.3 ID Tetramethrin 18 0 <0.2 <0.2 ND ND = non-detect; ID = insufficient data to calculate average; J = detected above MDL but below RL

Fipronil or fipronil degradates comprise 42 of 47 (89%) of the detected values. The range for fipronil and fipronil sulfone concentrations were <0.5 ng/L to 31 ng/L and 0.6 ng/L to 23 ng/L, respectively. Fipronil is a pesticide of concern based on detection in the water column and potential for aquatic life toxicity. Fipronil is a broad spectrum insecticide with many residential and commercial applications for controlling many pests such as ants, fleas, ticks, garden pests, and termites. It is also the leading replacement for pyrethroid pesticides in urban areas.

The results in this study are consistent with results from other studies of urban areas in California. Per a CASQA evaluation2 of statewide data from 2003 to 2012, the statewide average fipronil concentration (89.7 ng/L) is in fact higher than any concentrations observed in this study (31 ng/L). The evaluation showed 39% of samples detected fipronil though many of the studies evaluated by CASQA had higher detection limits than were used in this monitoring study. Percent detection is generally a poor indicator of impairments or for comparison purpose because they are highly dependent on the detection limits. It is better to compare results to water quality criteria; however none exist at this time for fipronil.

2 Ruby, Armand. Review of Pyrethroid, Fipronil and Toxicity Monitoring Data from California Urban Watersheds. Prepared for California Stormwater Quality Association. July 10, 2013. Accessed at https://www.casqa.org/sites/default/files/library/technical-reports/casqa_review_of_pyrethroid_fipronil_and_toxicity _ monitoring_ data_-_july_2013.pdf

MCSTOPPP and City of Petaluma 17 October 2016 2015-2016 Urban Creek Monitoring Report In the absence of water quality criteria, the monitoring results were compared against EPA benchmarks and thresholds referenced by the Central Valley Regional Water Quality Control Board (Central Valley Regional Water Board) in their current work towards establishing a TMDL guidelines to control pyrethroids in the Sacramento and San Joaquin river basins. The TMDL is tentatively scheduled for adoption in spring 2017. Table 17 shows several of the criteria and thresholds referenced by the Central Valley Regional Board in their TMDL development process as well as the lowest proposed criteria being considered. References for the values shown are included below the table.

Table 17. Pesticide Water Quality Thresholds and Comparison with Year 1 Results

Lowest EPA Proposed Water Quality Triggers TMDL Allocation Aquatic Life Based on UC Davis Studies (c) (a) Benchmark (b) Acute Chronic Value 2016 % Value 2016 % Value 2016 % Value 2016 % Parameter (ng/L) above (ng/L) above (ng/L) above (ng/L) above Diazinon 100 0% 105 0% ------Chlorpyrifos -- -- 40 0% ------Allethrin -- -- 1,050 0% ------Bifenthrin -- -- 1.3 0% 0.8 0% 0.1 44% Cyfluthrin -- -- 7.4 0% 0.8 0% 0.2 11% Lambda-Cyhalothrin -- -- 2 0% 0.7 0% 0.3 0% Cypermethrin -- -- 69 0% 1 0% 0.3 Deltamethrin: Tralomethrin -- -- 4.1 0% ------Esfenvalerate: Fenvalerate -- -- 1.7 0% 3 0% 0.3 17% Fenpropathrin -- -- 17 0% ------Fipronil -- -- 11 50% ------Fipronil Desulfinyl -- -- 590 0% ------Fipronil Sulfone -- -- 37 0% ------Tau-fluvalinate -- -- 100 0% ------Permethrin -- -- 1.4 13% 6 6% 1 6% Tetramethrin -- -- 1,850 0% ------Notes: ‘2016 % above’ refers to the percent of 2016 results above the indicate threshold value. ‘unk.’ indicates that the number of results above the threshold could not be determined. All results are non-detect and the threshold is lower than the MDL. ‘> ##%’ indicates that the detected concentration are above the threshold and that some of the non-detect values could be above the threshold as well. However, the threshold is lower than the MDL so it is unknown how many of the non-detect samples are above it. References: (a) Diazinon and Pesticide-Related Toxicity in Urban Creeks TMDL (b) Available at: https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks/aquatic-life-benchmarks- pesticide-registration#benchmarks (c) Central Valley Regional Water Quality Control Board, Pyrethroids Basin Plan Amendment Strawman Regulatory Approach, July 2016 Draft Framework available at: http://www.waterboards.ca.gov/centralvalley/water_issues/ tmdl/ central_valley_projects/central_valley_pesticides/pyrethroid_tmdl_bpa/2016_08_pyrbpa_strawman.pdf

MCSTOPPP and City of Petaluma 18 October 2016 2015-2016 Urban Creek Monitoring Report As seen in Table 17, with few exceptions, the 2016 observed concentrations meet the established TMDL allocation for Diazinon and the Lowest EPA Aquatic Life Benchmark (EPA benchmark)3. The exceptions are fipronil and permethrin where 50% and 13%, respectively, of the results are above the EPA benchmarks for these two constituents. If draft criteria proposed for pyrethroids are used for comparison instead of the established guidelines, most of the pyrethroid constituents would exceed those. The degree of exceedance is uncertain, given that the proposed pyrethroid criteria are lower than the MDLs used in this study. A more comprehensive analysis is planned at the end of Year 2 of the monitoring study when more data will be available and pyrethroid water quality objectives may be finalized. As mentioned, the pyrethroids results in this study are consistent with results from other studies of urban areas in California and it is important to note that even though control of pesticide discharges in urban runoff falls under the responsibility of municipalities and stormwater management agencies, local authorities such as MCSTOPPP and Petaluma have very limited control in pesticides sale and use. Local source control and runoff reduction efforts may not be able to reduce pesticide concentrations far enough to consistently meet water quality standards. However, a recent statewide effort is expected to have a far greater impact in reduction of pesticide discharge to surface waters. This effort, known as the Statewide Framework for Urban Pesticide Reduction4, was initiated by the State Water Resources Control Board in coordination with state and federal pesticide regulators such as the U.S. EPA Office of Pesticide Programs and the California Department of Pesticide Regulations (DPR). The Statewide Framework for Urban Pesticide Reduction aims to develop a statewide urban pesticides/toxicity monitoring framework and minimum pesticides source control requirements for urban storm water agencies. It is possible that a monitoring framework will be established with this study’s timeline. MCSTOPPP and Petaluma are closely following this state-wide effort through participation in the CASQA Pesticides Subcommittee. Relevant developments for the Statewide Framework for Urban Pesticide Reduction will be reported in the Year 2 Report as appropriate.

4.5. RECOMMENDATIONS FOR 2016-2017 Based on the review of sampling activities, analytical practices, and data observations for 2015- 2016, the following changes are proposed to monitoring in Year 2: Sampling Events Monitoring events for 2016-2017 should be increased to four wet-weather events and one dry weather event to compensate for the one event missed in Year 1. Wet weather sample collection timing should still target the rising portion of the hydrograph, but it is acceptable to sample at the peak or after the peak as long as flow conditions are known to be substantially storm-influenced.

3 Benchmarks, developed for baseline risk assessments, are estimates of the concentrations below which pesticides are not expected to harm aquatic life. These benchmarks are used to evaluate potential toxicity of a wide range of pesticides in fresh water but are not approved Office of Water Aquatic Life Criteria. 4 Information on the Statewide Framework for Urban Pesticide Reduction was accessed at: http://www.waterboards.ca.gov/water_issues/programs/stormwater/storms/obj6_proj6a.shtml

MCSTOPPP and City of Petaluma 19 October 2016 2015-2016 Urban Creek Monitoring Report Analytical Methods While reviewing the analytical methods employed in Year 1, it was noted that the 0.3 mg/L MDL for the TOC and DOC method is higher than the QAPP-specified MDL of 0.05 mg/L. Since all of TOC and DOC results were detected, this was not an issue for Year 1 sampling. Nevertheless, the issue should be clarified for Year 2. The MDL was incorrectly specified as 0.05 mg/L in the QAPP and will be revised to specify a 0.5 mg/L instead. The analytical laboratory developed a triple-quadrapole analytical method for pyrethroids to meet the lower detection limits soon to be required in the Central Valley and to improve detection rates. Because there were a large number of “not detected” pyrethroids this method should be employed for pyrethroid analysis in Year 2 if the new method performs adequately and all QAPP-specified constituents are included. Lower detection and quantification concentrations will better characterize conditions and improve comparison against the lower thresholds referenced or derived in the development of the pyrethroids TMDL (shown in Table 17).

MCSTOPPP and City of Petaluma 20 October 2016 2015-2016 Urban Creek Monitoring Report A TTACHMENT A Applied Marine Sciences Event 1 Field Report, Data Sheets, and Chain of Custody Forms Field Report

Diazinon and Pesticide-Related Toxicity TMDL Monitoring Program in Urban Creeks WY2016 Wet Season Event 1

January 8, 2016

Submitted to: Marin County Flood Control and Water Conservation District 3501 Civic Center Drive, Room 304 San Rafael, CA 94903 Attn: Terri Fashing

Submitted by:

4749 Bennett Drive, Suite L Livermore, CA 94551 925-373-7142

East Marin Pesticides Monitoring Field Report – WY2016 Event 1 1/8/15

1. Introduction Applied Marine Sciences, Inc. (AMS) was contracted by the Marin County Flood Control and Water Conservation District to conduct the Pesticide Water Quality Monitoring Project in East Marin Creeks. This work is being conducted in coordination with the City of Petaluma (COP), who is responsible for conduct of monitoring at two Petaluma River sites. This report summarizes activities associated with the first wet season monitoring event of 2016, conducted January 5, 2016.

1.1. Objectives The objectives of the sampling effort were as follows:

1. Collect storm-event ambient water samples from four sites for analysis of the following by Caltest Analytical (Caltest) • Pyrethroids, Fipronil, Diazinon, and Chlorpyrifos (pesticides) • Suspended Sediment Concentration (SSC) • Total Dissolved Solids (TDS) • Total Organic Carbon (TOC) • Dissolved Organic Carbon (DOC) 2. Collect storm-event ambient water samples from four sites for analysis of turbidity by COP. 3. Collect field measurements of temperature, dissolved oxygen, pH, and conductivity.

1.2. Personnel Personnel performing creek status monitoring are indicated in Table 1.

Table 1. Field Personnel for Wet Weather Event 1 Monitoring

Name Affiliation Duties Paul Salop AMS Sample collection Chris Atkins ADH Sample collection

Mr. Salop was responsible for oversight of sampling operations, compliance with QAPP and Monitoring Plan, maintenance of the sample field log, and chain-of-custody procedures.

1.3. Sampling Event Selection Sampling events are limited to daylight hours that are in close proximity to a lower low tide that allows COP to conduct monitoring on Petaluma River during a window around the predicted low tide. Between 2pm on January 4th and initiation of monitoring at 10am on January 5th, approximately 2” of rainfall were recorded at a rain gauge located at the San Rafael Country Club.1 Precipitation for the sampling date (January 5, 2016) and the ten-day period prior to sampling is shown in Figure 1.

1 Weather Underground station KCASANRA47, http://www.wunderground.com/personal-weather- station/dashboard?ID=KCASANRA47#history

East Marin Pesticides Monitoring Field Report – WY2016 Event 1 1/8/15

Precipitation Summary

2.5

1.5

0.5

0 12/25/15 12/27/15 12/29/15 12/31/15 1/2/16 1/4/16 1/6/16

Figure 1. Precipitation Record Sampling Date and Ten-day Antecedent Period. Precipitation data obtained from Weather Underground Station KCASANRA47.

1.4. Sampling Procedures All sampling conformed to protocols identified in the Project Quality Assurance Project Plan (QAPP) and Monitoring Plan (LWA 2015) and Sampling and Analysis Plan (SAP, AMS 2015).

1.5. Collection of Quality Assurance Samples As coordinated with COP and consistent with the Project QAPP and Monitoring Plan (LWA 2015), AMS collected all QA samples associated with implementation of Event 1 monitoring. QA samples are summarized in Table 2. By agreement with COP, COP will be responsible for collected QA samples at two of the remaining three events, to be coordinated on an ongoing basis.

Table 2. QA Samples Collected by AMS During Wet Weather Monitoring Event 1

Analyte QA Type / Frequency EB FB FD MS/MSD Pesticides X X X SSC X TDS X TOC X X X DOC X Turbidity X X

East Marin Pesticides Monitoring Field Report – WY2016 Event 1 1/8/15

1.6. Sampling Sites Locations of MCSTOPPP sites are shown in Figure 1. Sampling sites indicated by blue icons were sampled by AMS; those indicated by yellow icons were sampled by COP. Target and actual site coordinates for AMS sampling sites are listed in Table 2.

Figure 2. East Marin Creek Pesticides Monitoring Project Sampling Sites.

Table 3. Target and Actual Location Coordinates for MCSTOPPP Sampling Sites

Lat Long Site Code Site Name Target Actual Target Actual 206NOV160 Novato Creek at Lee Gerner Park 38.10700 -122.57863 203ACM070 Arroyo Corte Madera Del Presidio at La 37.89764 -122.53502 Goma Bridge 203COR060 Corte Madera Creek at Lagunitas Road 37.96321 -122.5571 Bridge 203SNR180 San Rafael Creek at D Street 37.97057 -122.53251 Overcrossing

East Marin Pesticides Monitoring Field Report – WY2016 Event 1 1/8/15

1.7. Sample Labeling The sample ID labeling system used for the Project is summarized below:

SITE-E#-NN

Where:

SITE = Site code E# = Event (i.e., E1, E2, E3, E4) NN = Successive sample number (e.g., 01, 02, 03)

1.8. Sample Handling After collection, sample containers were stored in a cooler and surrounded by double-bagged wet ice to speed cooling. Sample containers were hand-delivered to COP (turbidity) or Caltest (all others) immediately after conclusion of sampling operations.

1.9. Discussion Sampling of all sites was successfully completed between 10:00 am and 2:26 pm on January 5, 2016. As stated previously, approximately 2” of rainfall were recorded during the 20 hours preceding sample collection. Rainfall continued throughout the daylight hours of sampling, but at generally reduced intensity.

Flow determinations were made in the field by ADH at San Rafael Creek, which is the only Marin County monitoring station in this study without a local gauging station. Data were subsequently assembled for Corte Madera Creek using the local gauge data. It was determined after the first sampling event that there are no flow sensors at the Marin County stations at Arroyo Core Madera or Novato Creek. A USGS station is present less than 100m away from the monitoring site at Novato Creek, however. Thus these data are being used to assess flow for Novato Creek. There is no surrogate available for Arroyo Corte Madera (ACM). Therefore, for following sampling events, field staff will estimate flow at the time of sampling similar to San Rafael Creek, using channel geometry and surface velocity, then back up these data with rating calculations based on USGS methods over time. The City of Petaluma is responsible for determining flow at the two river sites. Flow measurements for MCSTOPPP sites are summarized below.

Field samples for assessment of turbidity and pesticide concentrations were collected at each of the sites. The respective laboratories reported EDDs on February 2, 2016.

East Marin Pesticides Monitoring Field Report – WY2016 Event 1 1/8/15

Table 4. Flow Information for MCSTOPPP Sampling Sites

Site Code Sampling Source of Flow Stage Height Flow (m3/s) Time Data (ft) 206NOV160 14:00 USGS Station 3.94 1.444 11459500 203ACM070 10:10 Marin County 3.97 N/A Station 5251 203COR060 11:40 Marin County 9.91 10.647 Station 5255 203SNR180 13:00 Field Estimated NA 0.625

2. References AMS, 2015. Sampling and Analysis Plan: Pesticide Water Quality Monitoring Project in East Marin Creeks and the Petaluma River. Prepared for MCSTOPPP. December 22, 2015.

LWA, 2015. BASMAA Monitoring Plan and Quality Assurance Project Plan: Diazinon and Pesticide- Related Toxicity TMDL Monitoring Program in Urban Creeks. Submitted to San Francisco Regional Water Quality Control Board. July 2015.

A TTACHMENT B Applied Marine Sciences Event 2 Field Report, Data Sheets, and Chain of Custody Forms Field Report

Diazinon and Pesticide-Related Toxicity TMDL Monitoring Program in Urban Creeks WY2016 Wet Season Event 2

March 9, 2016

Submitted to: Marin County Flood Control and Water Conservation District 3501 Civic Center Drive, Room 304 San Rafael, CA 94903 Attn: Terri Fashing

Submitted by:

4749 Bennett Drive, Suite L Livermore, CA 94551 925-373-7142

If you are a person with a disability and require an accommodation to participate in a County program, service, or activity, requests may be made by calling (415) 473-4381 (Voice), (415) 473-3232 (TDD/TTY), or by email at least four days in advance of the event. Copies of documents are available in alternative formats upon request

East Marin Pesticides Monitoring Field Report – WY2016 Event 2 4/8/16

1. Introduction Applied Marine Sciences, Inc. (AMS) was contracted by the Marin County Flood Control and Water Conservation District to conduct the Pesticide Water Quality Monitoring Project in East Marin Creeks. This work is being conducted in coordination with the City of Petaluma (COP), who is responsible for conduct of monitoring at two Petaluma River sites. This report summarizes activities associated with the second wet season monitoring event of 2016, conducted March 5, 2016.

1.1. Objectives The objectives of the sampling effort were as follows:

1.2. Personnel Personnel performing creek status monitoring are indicated in Table 1.

Table 1. Field Personnel for Wet Weather Event 2 Monitoring

Name Affiliation Duties Aroon Melwani AMS Sample collection Chris Atkins ADH Sample collection

Aroon Melwani was responsible for oversight of sampling operations, compliance with QAPP and Monitoring Plan, maintenance of the sample field log, and chain-of-custody procedures.

1.3. Sampling Event Selection Sampling events are limited to daylight hours that are in close proximity to a lower low tide that allows COP to conduct monitoring on Petaluma River during a window around the predicted low tide. Between 12am on March 5th and initiation of monitoring at 11am, approximately 0.5” of rainfall were recorded at a rain gauge located at the San Rafael Country Club. Precipitation for the sampling date (March 5, 2016) and the ten-day period prior to sampling is shown in Figure 1.

East Marin Pesticides Monitoring Field Report – WY2016 Event 2 4/8/16

Figure 1. Precipitation Record on Sampling Date and Ten-day Antecedent Period. Precipitation data obtained from Weather Underground Station KCASANRA47.

1.5. Collection of Quality Assurance Samples As coordinated with COP and consistent with the Project QAPP and Monitoring Plan (LWA 2015), COP collected all QA samples associated with implementation of Event 2 monitoring. QA samples are summarized in Table 2. COP will be responsible for QA samples at one of the remaining two events, to be coordinated on an ongoing basis.

Table 2. QA Samples Collected by COP During Wet Weather Monitoring Event 2

Analyte QA Type / Frequency EB FB FD MS/MSD Pesticides X X SSC TDS TOC X X DOC Turbidity X

East Marin Pesticides Monitoring Field Report – WY2016 Event 2 4/8/16

Figure 2. East Marin Creek Pesticides Monitoring Project Sampling Sites.

Table 3. Target and Actual Location Coordinates for MCSTOPPP Sampling Sites

Lat Long Site Code Site Name Target Actual Target Actual 206NOV160 Novato Creek at Lee Gerner Park 38.10700 38.10730 -122.57863 -122.57922 203ACM070 Arroyo Corte Madera Del Presidio at La 37.89764 37.89761 -122.53502 -122.53574 Goma Bridge 203COR060 Corte Madera Creek at Lagunitas Road 37.96321 37.96301 -122.5571 -122.5575 Bridge 203SNR180 San Rafael Creek at D Street 37.97057 37.97067 -122.53251 -122.53263 Overcrossing

East Marin Pesticides Monitoring Field Report – WY2016 Event 2 4/8/16

1.7. Sample Labeling The sample ID labeling system used for the Project is summarized below:

SITE-E#-NN

Where:

SITE = Site code E# = Event (i.e., E1, E2, E3, E4) NN = Successive sample number (e.g., 01, 02, 03)

1.8. Sample Handling After collection, sample containers were stored in a cooler and surrounded by blue ice blocks to speed cooling. Sample containers were hand-delivered to COP (turbidity) or Caltest (all others) immediately after conclusion of sampling operations.

1.9. Discussion Sampling of all sites was successfully completed between 11:30 am and 2:35 pm on March 5, 2016. As stated previously, approximately 0.5” of rainfall were recorded during the 20 hours preceding sample collection. Rainfall continued throughout the daylight hours of sampling, generally increasing in intensity.

Flow determinations were made in the field by ADH at Arroyo Corte Madera Del Presidio and San Rafael Creek, which are the two Marin County monitoring stations in this study without flow sensors. Data were subsequently assembled for Corte Madera Creek and Novato Creek using local gauge data. The City of Petaluma is responsible for determining flow at the two river sites. Flow measurements for MCSTOPPP sites are summarized below.

Field samples for assessment of turbidity and pesticide concentrations were collected at each of the sites. The respective laboratories reported EDDs on April 7th, 2016.

Table 4. Flow Information for MCSTOPPP Sampling Sites

Site Code Sampling Source of Flow Stage Height Flow (m3/s) Time Data (ft) 206NOV160 14:05 USGS Station 3.05 0.07 11459500 203ACM070 11:35 Field Estimated 3.39 1.14 203COR060 12:35 Marin County 7.86 2.80 Station 5255 203SNR180 13:15 Field Estimated 0.67 0.27

2. References AMS, 2015. Sampling and Analysis Plan: Pesticide Water Quality Monitoring Project in East Marin Creeks and the Petaluma River. Prepared for MCSTOPPP. December 22, 2015.

East Marin Pesticides Monitoring Field Report – WY2016 Event 2 4/8/16

A TTACHMENT C Applied Marine Sciences Event 3 Field Report, Data Sheets, and Chain of Custody Forms Field Report

Diazinon and Pesticide-Related Toxicity TMDL Monitoring Program in Urban Creeks WY2016 Event 3 – Dry Season Sampling

June 16, 2016

Submitted to: Marin County Flood Control and Water Conservation District 3501 Civic Center Drive, Room 304 San Rafael, CA 94903 Attn: Terri Fashing

Submitted by:

4749 Bennett Drive, Suite L Livermore, CA 94551 925-373-7142

East Marin Pesticides Monitoring Field Report – WY2016 Event 3 (Dry Season Sampling) 6/16/16

1. Introduction Applied Marine Sciences, Inc. (AMS) was contracted by the Marin County Flood Control and Water Conservation District to conduct the Pesticide Water Quality Monitoring Project in East Marin Creeks. This work is being conducted in coordination with the City of Petaluma (COP), who is responsible for conduct of monitoring at two Petaluma River sites. This report summarizes activities associated with the dry season monitoring event of 2016 (Event 3), conducted June 9, 2016.

1.1. Objectives The objectives of the sampling effort were as follows:

1. Collect dry-event ambient water samples from four sites for analysis of the following by Caltest Analytical (Caltest) • Pyrethroids, Fipronil, Diazinon, and Chlorpyrifos (pesticides) • Suspended Sediment Concentration (SSC) • Total Dissolved Solids (TDS) • Total Organic Carbon (TOC) • Dissolved Organic Carbon (DOC) 2. Collect dry-event ambient water samples from four sites for analysis of turbidity by COP. 3. Collect field measurements of temperature, dissolved oxygen, pH, and conductivity.

1.2. Personnel Personnel performing creek status monitoring are indicated in Table 1.

Table 1. Field Personnel for Wet Weather Event 3 Monitoring

Name Affiliation Duties Paul Salop AMS Sample collection Calvin Sandlin ADH Sample collection

Paul Salop was responsible for oversight of sampling operations, compliance with QAPP and Monitoring Plan, maintenance of the sample field log, and chain-of-custody procedures.

1.3. Sampling Event Selection Sampling events are limited to daylight hours that are in close proximity to a lower low tide that allows COP to conduct monitoring on Petaluma River during a window around the predicted low tide. Between 12am on June 1st and initiation of monitoring at 10am, 0” of rainfall were recorded at a rain gauge located at the San Rafael Country Club. The lack of precipitation for the sampling date (June 9, 2016) and the ten-day period prior to sampling is shown in Figure 1.

East Marin Pesticides Monitoring Field Report – WY2016 Event 3 (Dry Season Sampling) 6/16/16

Precipitation Summary 0.5

0.25

0 5/31/16 6/2/16 6/4/16 6/6/16 6/8/16 6/10/16

Figure 1. Precipitation Record on Sampling Date and Ten-day Antecedent Period. Precipitation data obtained from Weather Underground Station KCASANRA47.

Table 2. QA Samples Collected by COP During Wet Weather Monitoring Event 2

Analyte QA Type / Frequency EB FB FD MS/MSD Pesticides X X X SSC X TDS X TOC X X X DOC X Turbidity

East Marin Pesticides Monitoring Field Report – WY2016 Event 3 (Dry Season Sampling) 6/16/16

Figure 2. East Marin Creek Pesticides Monitoring Project Sampling Sites.

Table 3. Target and Actual Location Coordinates for MCSTOPPP Sampling Sites

Lat Long Site Code Site Name Target Actual Target Actual 206NOV160 Novato Creek at Lee Gerner Park 38.10700 38.10730 -122.57863 -122.57937 203ACM070 Arroyo Corte Madera Del Presidio at La 37.89764 37.89803 -122.53502 -122.53609 Goma Bridge 203COR060 Corte Madera Creek at Lagunitas Road 37.96321 37.96256 -122.5571 -122.55684 Bridge 203SNR180 San Rafael Creek at D Street 37.97057 37.97064 -122.53251 -122.53262 Overcrossing

East Marin Pesticides Monitoring Field Report – WY2016 Event 3 (Dry Season Sampling) 6/16/16

1.7. Sample Labeling The sample ID labeling system used for the Project is summarized below: SITE-E#-NN Where: SITE = Site code E# = Event (i.e., E1, E2, E3, E4) NN = Successive sample number (e.g., 01, 02, 03)

1.9. Discussion Sampling of all sites was successfully completed between 10:15 am and 1:40 pm on June 9, 2016. As stated previously, no precipitation was recorded during the preceding several days from sample collection. Rainfall had not been recorded at any of the sites since May 27, 2016. Prior to the 0.1” of precipitation on that day, there had not been any rain in the region since May 5, 2016. The general lack of precipitation in the region supports the rationale for the dry-season sampling that took place on June 9th.

Flow determinations were not possible at either Arroyo Corte Madera Del Presidio or San Rafael Creek, which are the two Marin County monitoring stations in this study without flow sensors. This was because surface velocity was too low at locations nearby to monitoring locations with uniform profiles to make accurate measurements. Data were subsequently assembled for Corte Madera Creek and Novato Creek using local gauge data. The City of Petaluma is responsible for determining flow at the two river sites. Flow measurements for MCSTOPPP sites are summarized below.

EDDs are expected from the respective laboratories in July 2016.

Table 4. Flow Information for MCSTOPPP Sampling Sites

Site Code Sampling Source of Flow Data Stage Flow Time Height (ft) (m3/s) 206NOV160 13:40 USGS Station 11459500 2.97 0.05 203ACM070 10:15 N/A 2.90 N/A 203COR060 11:35 Marin County Station 5255 6.99 0.65 203SNR180 12:15 N/A 0.67 N/A

2. References AMS, 2015. Sampling and Analysis Plan: Pesticide Water Quality Monitoring Project in East Marin Creeks and the Petaluma River. Prepared for MCSTOPPP. December 22, 2015.