The Sacramento Branch Presents
Factors Affecting 1,2,3-Trichloropropane in Groundwater in California
Karen Burow
Research Hydrologist with the US Geological Survey
PRESENTATION:
1,2,3-TCP is a volatile organic chemical of eminent concern due to its carcinogenic, mutagenic, and reproductive effects, and its frequent occurrence at concentrations of concern worldwide. California recently established a maximum contaminant level (MCL) for 1,2,3-TCP of 0.005 μg/L.
Statewide, 1,2,3-TCP was detected at concentrations above the MCL in 6.5% of 1,237 wells sampled by the U. S. Geological Survey (USGS). About 8% of domestic wells had a detection of 1,2,3-TCP, compared to 5% of public-supply wells. 1,2,3-TCP was detected at or above 0.005 μg/L in 5.5% of most recent samples from 7,787 public-supply well sources of the California State Water Resources Control Board Division of Drinking Water (DDW). Concentrations ranged from <0.005 to 2.7 μg/L.
Most of the detections occurred in the San Joaquin Valley, where 1,2,3-TCP was detected above the MCL in 16% of USGS sampled wells and 18% of DDW wells. In the San Joaquin Valley, 1,2,3-TCP occurrence and concentrations are related to legacy nonpoint source fumigant inputs and hydrogeologic factors. The highest concentrations of nonpoint-source 1,2,3-TCP are in young, shallow, oxic groundwater beneath primarily orchard/vineyard crops. These areas are in coarse-grained sediments that promote rapid recharge. 1,2,3-TCP frequently co-occurs with 1,2-dibromo-3-chloropropane (DBCP), 1,2-dichloropropane (1,2-DCP), simazine, and high nitrate concentrations. Analysis of groundwater age dates and temporal changes in 1,2,3-TCP indicate that 1,2,3-TCP is persistent throughout modern age groundwater, showing little evidence of degradation.
SPEAKER BIO:
Karen Burow is a Research Hydrologist with the US Geological Survey in Sacramento, where she serves as a senior technical specialist for the California Ambient Groundwater Monitoring and Assessment Project (GAMA). Karen has worked for the USGS since 1992 on assessment and trends in groundwater quality at local, regional, and national scales. Karen’s primary interests include the fate and transport of nitrate and pesticides in groundwater, and investigation of natural contaminants in regional aquifers. Karen has used a wide range of techniques to investigate hydrogeologic systems and to determine the physical and chemical processes affecting the vulnerability of groundwater drinking-water resources.
SCHOLASTIC SPONSOR:
ABOUT: Blaine Tech Services (WBE/WOSB)
Blaine Tech Services (WBE/WOSB) is a specialty contractor that focuses exclusively on field sampling and support services. Our trained technicians operate custom, purpose-built vehicles and can safely and efficiently execute the most complex field sampling procedures on the most challenging sites. Groundwater sampling services include Low-Flow sampling, PDB, HydraSleeve and CMT sampling, deep well sampling (1,000’ + bgs), Westbay System sampling and traditional purging & sampling. Related field services include Soil Vapor Sampling, In-Situ Remediation Support, Soil Sampling, Well Development, System O&M, Pump Test Support and Wellhead Repair & Maintenance Six offices in Washington, California and Arizona serve the West Coast and beyond. Visit us as www.blainetech.com.
For a quote or more information contact:
Dave Webb, bwebb@blainetech.com, 408-590-0572
Francis Thie, fthie@blainetech.com, 408-573-0555 x 201
ANNOUNCING SCHOLASTIC SPONSORSHIP OPPORTUNITIES:
All Proceeds to Benefit Science Students
The GRA Sacramento Branch has a history of supporting university-level science students. Our Scholastic Sponsorship Program is an opportunity to publicize your business while contributing toward a good cause. The cost is minimal; if interested, please contact Michael Bombard at (916) 865-5301 or Michael.Bombard@ghd.com.
AGENDA:
Social Hour - 5:30-6:30 p.m.
Announcements & Dinner - 6:30-7:30 p.m.
Presentation - 7:30-8:30 p.m.
Usual great food, including two meat entrées, salad, rice, potatoes, vegetable and iced tea. A no-host beer and wine bar will be available.
MEETING COSTS AND RSVP:
EARLY BIRD MEETING COSTS
Members: $27.00
Non-Members: $32.00
Students: $10.00
Cancellations must be made by Noon on Monday, September 9th.
If you register after Noon on Monday, September 9th, or walk-in, a $3.00 surcharge will be added to the meeting cost.
If you have questions about the meeting, please call Rodney Fricke at 916-407-8539 or email him at rodneyafricke@gmail.com. For questions about Sacramento Branch in general, including submittal of your ideas and/or desires for future presentations, please call Linda Bond at (530) 757-1500 or email her at Linda.Bond@water.ca.gov.
UPCOMING MEETINGS & EVENTS:
October 9, 2019: Laura Foglia, Ph.D., Understanding surface water/groundwater interactions: lesson learned from Scott Valley
November 13, 2019: Kent Parrish, Wood, Abandoned Mine Lands: What are they? How big of an issue? What’s the big deal?
December 11, 2019: Annual Joint GRA-AEG Holiday Meeting – 2019 NGWA McEllhiney Lecture Gary L. Hix, Drilling Disasters and What Can We Learn