Paul Kirby, P.G. Daniel B. Stephens & Associates, Inc. with. Fayette County GCD Pecan Valley GCD. August 29, 2018

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1 Paul Kirby, P.G. Daniel B. Stephens & Associates, Inc. with Fayette County GCD Pecan Valley GCD August 29, 2018

2 Typical GCD Mission To provide for the conservation, preservation, protection, recharging, and prevention of waste of groundwater and groundwater reservoirs...protecting, preserving and conserving aquifers......manage and protect the groundwater resources...

3 Protecting Groundwater Most districts have active groundwater level monitoring programs Fewer are developing datasets of baseline water quality Quantity and quality are important Is there enough water? Is it safe to use?

4 Statewide Historic Water Quality Samples Source: TWDB Database

5 Single-District Water Quality Studies Fayette County GCD approved a study in 2013; concluded in 2017

6 Single-District Water Quality Studies Pecan Valley GCD (DeWitt County) approved a study in 2014; concluded in 2018

7 Purpose of Studies Collect new data to provide additional baseline water quality measurements Establish baseline measurements for activities of concern (fracking, uranium mining, etc.) Evaluate current water quality data and compare to historical studies/data

8 Project Tasks Define project objectives Review historic data Identify wells to sample and contact well owners Field work Analytical Reporting

9 Project Objectives What aquifers will be evaluated? Sampling distribution goals Water quality issues/potential issues to address Develop appropriate analytical suites to evaluate general water quality as well as any specific issues identified

10 FCGCD Hydrogeologic Units System Series Group Quaternary Tertiary Pleistocene and Recent Miocene Formation / Aquifers Approximate Thickness (feet) Hydrogeologic Units Alluvium 0 to 60± Alluvium Oakville Sandstone and 0 to 950 Lagarto Clay Catahoula Tuff 0 to 500 Gulf Coast Oligocene Frio Clay 0 to 520 Jackson Jackson 0 to 1,100 Yegua 0 to 900+ Yegua - Jackson Cook Mountain 0 to 450+ Sparta Sand 0 to 275 Sparta Claiborne Weches 50 to 150 Eocene Queen City Sand 480 to 750 Queen City Wilcox Recklaw 225 to 500+ Carrizo Sand 200 to 300+ Calvert Bluff Simsboro 2,400 to 3,800 Hooper Carrizo-Wilcox

11 Aquifer Location

12 Sample Distribution Goal

13 PVGCD Wells Sampled

14 Water Quality Issues to Evaluate

15 Analytical Suites Basic inorganic suite Additional analytic suites for issues of concern Hydraulic Fracking Uranium Mining SVOCs Other?

16 Historic Data Review Geology and hydrostratigraphy Location and extent of aquifers Historic water quality studies/data Wells previously sampled or measured water levels Other reports/sources?

17 Well Selection After determining desired distribution of wells, identify candidate wells Can be difficult- depends on data quality available for wells Contact well owners for permission to sample Involves extensive PR This effort very useful in developing relationships with well owners

18 Time to go sample!!

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20 Purge well for 15 minutes Collect samples directly from faucet Preserve-Label-Seal- Store (on ice) Deliver to lab Sampling Protocol

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22 Analytical Results Review and QA/QC Any detections of concern that warrant confirmation sampling? Begin compiling your data for analysis and reporting Data evaluation Assess by aquifer Comparison to drinking water standards Comparison to historic data/studies Analysis of geographic trends (if any)

23 Drinking Water Standards Primary Standards MCLs (maximum contaminant levels) Legally enforceable Health-based limits set by the USEPA Secondary Standards EPA or state standards Not enforceable Relate mainly to aesthetics (taste, color, odor, etc.)

24 Primary Drinking Water Standards Analyte Primary MCL (mg/l) Fluoride 4 Nitrate 10 Arsenic 0.01 Barium 2 Beryllium Cadmium Chromium 0.1 Mercury Lead (Action Level) Antimony Selenium 0.05 Thallium 0.002

25 Secondary Drinking Water Standards Analyte Standard (mg/l) Aluminum Chloride 300 Copper 1 Fluoride 2 Iron 0.3 Manganese 0.05 ph Silver 0.1 Sulfate 300 TDS 1,000 Zinc 5

26 Comparison to Historical Results Historical water quality data from TWDB Previous studies (TWDB reports, other reports)

27 FCGCD Results Primary Analytes Analyte TWDB Historic Range (mg/l) Range from Study (mg/l) Calcium 1-1, Magnesium Potassium Sodium 3-1, ,020 Iron ND - 18 ND Chloride 5-3, Fluoride ND Sulfate ND - 1,664 ND - 1,430 Nitrate ND ND - 87 Total Dissolved Solids 50-8, ,710 Alkalinity, Bicarbonate ND - 1,147 ND ph

28 FCGCD Results Primary Analytes Analyte Drinking Water Standard Primary Secondary Range (mg/l) Number above DWS Calcium Magnesium Sodium Potassium Iron 0.3 ND Fluoride 4 2 ND Chloride Sulfate 300 ND - 1, Alkalinity, Bicarbonate ND Total Dissolved Solids 1, Nitrate 10 ND ph

29 Analytes Detected Above DWS Numerous analytes exceeded applicable DWS Primary standard (MCL) Arsenic and nitrate Other analytes sporadically exceeded Secondary standards TDS, chloride, sulfate, iron, manganese Other analytes sporadically exceeded

30 Confirmation Sampling Detections in selected wells may be resampled to confirm presence of certain analyte(s) Done in coordination with the GCD and well owner.

31 Geographic Trends Assessment of data for trends- primarily TDS Geographic trends generally not discernable in PVGCD In FCGCD, attempted to determine downdip 1,000 mg/l TDS line

32 PVGCD Historic TDS

33 PVGCD Current Study TDS

34 FCGCD Jackson Aquifer TDS

35 FCGCD Yegua Formation TDS

36 Summary Successfully sampled 277 wells in Fayette County and 164 wells in DeWitt County Good distribution across study area and by aquifer system Results generally in line with historic TWDB data and/or previous studies Valuable data set to establish county-wide baseline for water quality Expands number of wells with historic data

37 Summary A few wells above primary drinking water standard (MCL)- arsenic, nitrate, chromium, fluoride, lead, selenium Numerous wells above the secondary drinking water standards - TDS, chloride, sulfate, iron, manganese - not unexpected

38 Summary Significant groundwater quality data collection studies being done by the state are at a much larger scale--will not have a lot of data in each county It is up to individual districts to collect and assess this data within their district This includes baseline water quality data and data to assess any unique issues a district may be concerned about

39 Questions?????