Hydrogeologic. Valley Waste Disposal Company Cymric Field. Characterization Workplan Easton Drive. t ý4k. Prepared for.

Transcription

1 z 8 NOW Hydrogeologic Characterization Workplan Valley Waste Disposal Company Cymric Field t. Prepared for Walley Waste Disposal Company 400 Easton Drive Suite 39-B Bakersfield CA August 200 atr k wl t ý4k t tx 4L.t..c... i ý.ý MTh -

2 egomega-2995 Baseline Road Suite 202 Boulder CO Tel Fax August 200 Mr. Larry Bright Manager Valley Waste Disposal Company 400 Easton Drive Suite 39-B Bakersfield CA Dear Larry Attached are eight 8 copies of the final Hydrogeologic Characterization Workplan Valley Waste Disposal Company Cymric Field. This workplan was developed to fulfill Central Valley Regional Water Quality Control Board requirements outlined in a letter from Mr. Jim Dowdall dated April The final workplan incorporates comments received from the Valley Waste Groundwater Committee and also from Mr. Dowdall in letter dated July Please note that in an effort to reduce redundancy this final workplan does not include Appendicies A and B State guidelines for installing monitoring wells and collecting groundwater samples from our previous submittal. It appears that the Safety Kleen facility on Lokern Road is down slope and downgradient of the ponds in question. Historic groundwater monitoring data from this RCRA facility can be incorporated into our study to help characterize the alluvial aquifer system adjacent to Cymric. Call me at x03 if you have any further questions concerning this work plan. As always it has been my pleasure to have the opportunity to work with you. Sincerely Jeffrey A. Anderson Principal Hydrogeologist CA R.G. No QED GF GZG Attachments jr JEFFREY A. ANDERSON o 9 FOPCA-ý4O TO Good Science Hard Work Creative Thinking

3 Hydrogeologic Characterization Workplan Valley Waste Disposal Company Cymric Field Prepared for Valley Waste Disposal Company 400 Easton Drive Suite 39-B Bakersfield CA Prepared by Geomega Inc Baseline Road Suite 202 Boulder CO 80303

4 Hydrogeologic Characterization Workplan Valley Waste Disposal Company Cymric Field Table of Contents Section Page INTRODUCTION FIELD PROGRAM BOREHOLE DRILLING SOIL SAMPLING GEOPHYSICAL LOGGING WELL CONSTRUCTION MONITORING WELL DEVELOPMENT GROUNDWATER SAMPLING AQUIFER SLUG TESTS OFFICE WORK WATER QUALITY ANALYSES ANALYZE SLUG TESTS PREPARE TABLES PREPARE GRAPHS PREPARE MAPS REPORT WRITING SCHEDULE REFERENCES List of Figures Figure. Cymric site and proposed monitoring well locations Figure 2. Proposed time schedule for hydrogeologic characterization List of Appendices not included in final revised version Appendix A State accepted well construction and development procedures Appendix B State accepted groundwater sampling procedures

5 4 a i Introduction A surface geophysical investigation was performed on the Valley Waste Disposal Company VWDC McKittrick -3 facilities located just east of the Cymric oilfield to determine the areal and vertical extent of produced water infiltration downgradient of this percolation pond system Strata Geophysical However the surface geophysical survey was ambiguous in delineating produced water impacts at this site. VWDC forwarded recommendations to the California Regional Water Quality Control Board RWQCB that a conventional subsurface investigation of the area be performed to characterize the hydrogeologic conditions near the ponds. The RWQCB concurred with this recommendation and requested that a work plan be developed for a more conventional subsurface investigation which includes borings geophysical logs and groundwater samples RWQCB April 200. The following workplan proposes additional characterization of the area to determine the hydrogeologic conditions and the lateral extent of the mixing front of native groundwater with produced oilfield water disposed at the Cymric facility. The objectives of this investigation are to. Gather hydrogeology and geochemistry data in the Cymric area to characterize the hydrogeologic conditions adjacent to the VWDC McKittrick -3 disposal facilities. 2. Delineate the extent of the produced water mixing front downgradient of the VWDC McKittrick -3 disposal facilities. The recommended approach of this study is to acquire field data from three wells situated in a triangular pattern northeast of the McKittrick -3 ponds Figure. Hydrogeologic and geochemical data will be obtained from each of these proposed wells - 3

6 to characterize the groundwater flow system and to determine the extent of the mixing front of produced water. It is recommended that the following data be gathered Whole core intervals adjacent to the water table from each wellbore Geophysical logs Collection of water samples and analyses for inorganic organic and stable oxygen/hydrogenisotopes Insitu aquifer testing slug test I -2 ýr4.

7 L 2 Field Program 2. Borehole Drilling On the basis of the Safety Kleen facility groundwater monitoring data Chevron Eklund USL 56-8 well log and topography maps of the area the following depths are anticipated for each well. Total depths were estimated for the boreholes assuming that each well penetrate 00 feet into the saturated zone for geophysical logging. Well prefixes are assigned to match the study area. Well No. Location -GS Elev ft -Depth to GW ft -Total Depth ft CYM-IF F S20T29SR22E CYM-2J J S7T29SR22E CYM-3D D S20T29SR22E These boreholes are proposed to characterize the groundwater hydrology conditions at the site and to determine the extent of the produced water mixing front downgradient of the Cymric ponds. Existing groundwater monitoring of the shallow alluvial aquifer is available from the Safety Kleen facility located in Section 6 T29S R22E approximately.5 miles northeast of the McKittrick and -3 ponds. These data will be incorporated into this investigation to better characterize the hydrogeology of the shallow aquifer in the area. Each borehole will be drilled from ground surface to the first occurrence of groundwater using air rotary drilling. After encountering first groundwater the casing advanced for air drilling will be pulled and drilling will switch to the mud rotary method to total depth of the bore. A 50-foot surface conductor casing will be left in the hole to control the shallow unconsolidated sediments and minimize lost circulation problems. This combination of drilling methods will provide a definitive interpretation of the local water table and it. will allow for a complete suite of geophysical logs to be obtained in each borehole. 2-

8 2.2 Soil sampling A continuous core sample will be collected near the water table in each proposed well bore. A 94-mm diameter Christensen coring system will be employed to collect the soil core samples. Core will be retrieved in 5-foot barrels via a wire line run inside the drill pipe. The amount of core obtained in each borehole will be determined in the field by the supervising geologist and verbal agreement with VWDC representatives. Core samples will be analyzed for lithology presence of water and selection for additional soil property laboratory testing. 2.3 Geophysical Logging Geophysical logs will be acquired from each borehole from total depth to the base of the conductor casing. Resistivity spontaneous potential natural gamma ray caliper bulk density and neutron porosity logs will be obtained. Logs curves will be used to identify lithologies the presence of groundwater and aquifer-like zones capable of transmitting groundwater. These logs will also be employed to correlate the shallow stratigraphy with the limited historic well logs in the area. 2.4 Well construction In general the wells will be completed across the water table with 60 feet of factory machined 0.02-inch slots. The screen will approximately straddle the water table to allow for groundwater fluctuations either up or down. Monitoring wells will be constructed with 5-inch diameter schedule 80 PVC pipe. The following procedures will be performed for well construction. Determine desired completion interval based on geology description core samples and geophysical logs. 2. Plug back bottom of borehole using cement grout and bentonite pellets. 2-2

9 3. Assemble well screen with blank and end cap into borehole on blank casing to approximate completion depth. 4. Gravel pack well by pumping No. 3 Monterey sand from plug-backed total depth to 5 feet above the top of the well screen. 5. Pump 0-foot bentonite seal above the gravel pack. 6. Cement annulus from top of bentonite seal to ground surface with a mixture of Type I/II cement and bentonite in 00 foot lifts to ensure the PVC does not collapse or melt. Lifts should cure for sufficient time to gain compressive strength to support subsequent lifts. 7. Pull out conductor casing and cut PVC pipe approximately 3 feet above ground surface. Install steel cover with lock over PVC stub and burn well number in top plate with welder. 8. Pour concrete apron with traffic guard. 9. Survey well location ground surface elevation and top of casing. State accepted procedures will be strictly followed during well construction and development Appendix A. 2.5 Monitoring well development After each well has properly cured the monitoring well will be developed using a combination of air lift swabbing and pumping to remove drilling mud and fine grained material from the well screen and filter pack. During well development field parameters including ph temperature and specific conductance will be monitored. The well will not be considered fully developed until the field parameters stabilize within 5 percent of the previous reading. 2.6 Groundwater sampling After the monitoring wells have been properly developed and allowed to recharge a representative groundwater sample will be collected using a submersible pump or bailer. 2-3

10 Appropriate water samples will be collected for the following laboratory analyses general inorganics total petroleum hydrocarbons aromatic hydrocarbons BTEX and stable oxygen/hydrogen isotopes Static water level and well total depth will be measured during the sampling event. Each sample will be properly labeled to document well number date time and sampler. Samples will be stored in an insulated container at 4C as appropriate. The containers will be transported under appropriate chain of custody to state-certified laboratories. State accepted groundwater sampling procedures will be followed Appendix B. 2.7 Aquifer slug tests Upon proper construction development and sampling of each monitoring well aquifer slug tests will be performed. A slug of water will be rapidly removed with a positive displacement mechanism from the well bore and the water level rebound measured rising head test with an electronic pressure transducer and data logger. The water table return will be measured until it is within 5 percent of the original water level. A second rising head test will be performed after the water table has recovered as confirmation for the initial test. L 2-4 tf

11 3 Office work 3. Water quality analyses Each groundwater sample will be analyzed for general inorganics including major anions/cations total dissolved solids and boron. It is recommended that these wells be analyzed for BTEX compounds total petroleum hydrocarbons and stable isotopes of oxygen and hydrogen during this initial sampling round to establish baseline conditions for the site. 3.2 Analyze slug tests Aquifer slug test data will be processed and analyzed using software with appropriate curve-fit analytical solutions for tests of this nature. The Bouwer and Rice analytical solution is generally the appropriate evaluation tool for slug tests. Time and head data will be to the later time data and transmissivity calculated from the analysis. 3.3 Prepare tables A groundwater database for the Cymric area will be developed on the basis of the newly acquired field data and the available Safety Kleen groundwater monitoring data. Tables will be prepared to summarizewell construction water level water quality and aquifer properties. 3.4 Prepare graphs Standard geochemistry Piper diagrams and Stiff plots will be constructed for the inorganic water samples collected in the study area. A graph of del 08 and del D will be constructed for all isotopic samples to demonstrate their relationship to the meteoric water line. 3-

12 s 3.5 Prepare maps Geographic information system GIS predicated maps will be constructed for an appropriate geologic marker the water table and chloride isoconcentration. 3.6 Report writing A report will be prepared that documents the findings of this proposed hydrogeologic characterization of Cymric. Graphs maps tables and narrative will be included in the final report which will be submitted to the Central Valley RWQCB for review. x. S i 3-2

13 I t 4 Schedule A proposed schedule for implementation of the above-described hydrogeologic characterization for the Cymric west pond facilities is included for your review Figure 2. Field work will consist of Selecting a drilling contractor Project planning Well drilling and sampling Office work will consist of Analyses and interpretation of data Report writing A series of Central Valley RWQCB review and comment periods have been incorporated into the schedule. 4-

14 I L 5 References RWQCB April Letter from Mr. James K. Dowdall and Mr. Shelton R. Gray to Mr. Larry Bright Valley Waste Disposal Company. Strata Geophysical Inc. November Electrical Geophysical Survey Valley Waste Disposal Company Percolation Ponds McKI McK -3 Kern County California. 5-

15 2.5 Monitoring well development After each well has properly cured the monitoring well will be developed using a combination of air lift swabbing and pumping to remove drilling mud and fine grained material from the well screen and filter pack. During well development field parameters including ph temperature and specific conductance will be monitored. The well will not be considered fully developed until the field parameters stabilize within 5 percent of the previous reading. 2.6 Groundwater sampling I After the monitoring wells have been properly developed and allowed to recharge a representative groundwater sample will be collected using a submersible pump or bailer. Appropriate water samples for general inorganics total petroleum hydrocarbons aromatic hydrocarbons BTEX and stable oxygen/hydrogen isotopes will be collected in laboratory supplied containers. Static water level and well total depth will be measured during the sampling event. Each sample will be properly labeled to document well number date time and sampler. Samples will be stored in an insulated container at 4C as appropriate. The containers will be transported under appropriate chain of custody to state-certified laboratories. State accepted groundwater sampling procedures will be followed Appendix B. 2.7 Aquifer slug tests Upon proper construction development and sampling of each monitoring well aquifer slug tests will be performed. A slug of water will be rapidly removed with a positive displacement mechanism from the well bore and the water level return measured rising head test with an electronic pressure transducer and data logger. The water table return will be measured until it is within 5 percent of the original water level. A second rising head test will be performed after the water table has recovered as confirmation for the initial test. 2-3

16 S Figures i y

17 Cymric i i i i i f l i i f LRiDGýý McKittrick Ponds Proposed Monitoring 4-Existing rwell Locations Well Fields Oil Kleen Facility Safety Aqueducts I East Ponds Range -Section Drainages Township A 5 State Highway Light Duty Road N 56-8 r6n Chey 33Kleen Other Road Miles 0 % laci3tty.. JI okern Road Lokern Road 3D CY v WDC McKittrick -F/ 2 2-I Y r ý3 ckittrick k. LL / N 4 3K S T -ý Generation - well locations. proposed monitoring and Site Valley Waste. Figure Date 8/2/0 Geomega \\dm\t\projects\valleyw ste\cymic.apr cymric site layout f

18 38 Proposed Time Schedule Hydrogeologic Characterization VWDC Cymric Field 2. Figure Task Name Duration 08/0/0 Wed 0 ID days 65 Field work days 20 Project planning 2 days 45 sampling and Well drilling 3 days 60 Office work 4 5 days 30 interpretation and Analyses 6 days 30 Report writing 7 days days 0 Board to II II report Submit Phase 8 02b0 70 report Phase of Board review 9 0 Split External Tasks Up Rolled f Task Milestone Milestone Project Summary Up Project schedule Split Summary Rolled Date 08/0/0 Wed Progress Up Task Rolled Up Progress Rolled p\vwd\cymric\workplan\ workplan schedule.mpp Page