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HomeMy WebLinkAbout1302_CabarrusCDLF_Phase3_4_DesignHydro_DIN27243_January2017 i Table of Contents 1. Purpose and Scope 1.1 Report Contents ............................................................................................................................................................. 1-1 1.2 Previous Investigations ............................................................................................................................................... 1-1 1.2.1 C&D Landfill Investigation – Phase 1 .................................................................................................... 1-2 1.2.2 C&D Landfill Investigation – Phase 2 .................................................................................................... 1-2 1.2.3 Monitoring Well Installation .................................................................................................................... 1-4 1.2.4 C&D Landfill – Phase 2 Expansion ......................................................................................................... 1-4 1.2.5 Monitoring Well Installation – Phase 2 Expansion ......................................................................... 1-5 1.2.6 Alternate Source Demonstration ............................................................................................................ 1-5 1.3 Current Investigation ................................................................................................................................................... 1-5 2. Methodology 2.1 Drilling Methods ............................................................................................................................................................. 2-1 2.1.1 Borehole Drilling ........................................................................................................................................... 2-1 2.1.1.1 Hollow-Stem Auger Drilling ................................................................................................. 2-1 2.1.1.2 Rock Coring ................................................................................................................................. 2-1 2.2 Piezometer Installations ............................................................................................................................................. 2-2 2.3 Water Level Measurements ...................................................................................................................................... 2-2 2.4 Piezometer Surveying .................................................................................................................................................. 2-2 2.5 Slug Tests .......................................................................................................................................................................... 2-4 2.6 Geotechnical Testing .................................................................................................................................................... 2-4 3. Current Investigation Results 3.1 Site Geology ...................................................................................................................................................................... 3-1 3.1.1 Drilling Observations .................................................................................................................................. 3-1 3.1.1.1 Residuum ..................................................................................................................................... 3-3 3.1.1.2 Saprolite ....................................................................................................................................... 3-3 3.1.1.3 Partially Weathered Rock ..................................................................................................... 3-3 3.1.1.4 Bedrock......................................................................................................................................... 3-4 3.2 Testing Program ............................................................................................................................................................. 3-7 3.2.1 Standard Penetration Testing .................................................................................................................. 3-7 3.2.2 Particle Size Analysis and Unified Soil Classification .................................................................... 3-7 3.2.3 Formation Descriptions ............................................................................................................................. 3-7 3.2.4 Geotechnical Laboratory Testing ........................................................................................................... 3-7 3.2.5 Dispersive Characteristics ......................................................................................................................... 3-9 3.3 Site Hydrogeology ...................................................................................................................................................... 3-10 3.3.1 Water Level Measurements ................................................................................................................... 3-10 3.3.1.1 Horizontal and Vertical Gradients ................................................................................. 3-10 3.3.1.2 Temporal Trends ................................................................................................................... 3-18 3.3.2 Slug Test Results......................................................................................................................................... 3-21 3.4 Hydrogeological Conceptual Model .................................................................................................................... 3-25 3.4.1 Precipitation and Groundwater Recharge....................................................................................... 3-25 3.4.2 Groundwater Flow ..................................................................................................................................... 3-28 3.4.2.1 Groundwater Velocity ......................................................................................................... 3-28 Phase 3 and Phase 4 Expansions – Design Hydrogeologic Report • Table of Contents ii 3.4.3 Surface Water Interactions and Groundwater Discharge ......................................................... 3-29 3.5 Groundwater Conditions ......................................................................................................................................... 3-29 3.5.1 Groundwater Quality ................................................................................................................................ 3-29 3.5.2 Groundwater Assessment and Remediation ...................................................................................... 3-31 4. Conclusions 4.1 Landfill Construction Considerations .................................................................................................................... 4-1 4.2 Water Quality Monitoring Plan Considerations ................................................................................................ 4-1 4.3 Piezometer and Monitoring Well Abandonment .............................................................................................. 4-1 5. References Phase 3 and Phase 4 Expansions – Design Hydrogeologic Report • Table of Contents iii List of Figures Figure 1-1 Site Map ............................................................................................................................................................. 1-3 Figure 3-1 Bedrock Contour Map ................................................................................................................................. 3-5 Figure 3-2 Groundwater Contour Map .................................................................................................................... 3-12 Figure 3-3 Average Monthly Precipitation ............................................................................................................ 3-20 Figure 3-4 Seasonal High GW ...................................................................................................................................... 3-22 Figure 3-5 Long-Term Seasonal High GW .............................................................................................................. 3-23 Figure 3-6 Cross-Section A-A’ ...................................................................................................................................... 3-26 Figure 3-7 Cross-Section B-B’ ...................................................................................................................................... 3-27 List of Tables Table 2-1 Piezometer and Monitoring Well Completion Summary ............................................................. 2-3 Table 3-1 Summary of Lithologic Data ..................................................................................................................... 3-2 Table 3-2 Summary of Rock Core Observations ................................................................................................... 3-6 Table 3-3 Summary of Geotechnical Testing Results ......................................................................................... 3-8 Table 3-4 Water Level Measurements ................................................................................................................... 3-11 Table 3-5 Historic MW Water Levels ..................................................................................................................... 3-13 Table 3-6 Monthly Precipitation Data Summary............................................................................................... 3-19 Table 3-7 Hydraulic Conductivity Summary ....................................................................................................... 3-24 Table 3-8 Summary of Calculated Groundwater Flow Velocities .............................................................. 3-30 Table 3-9 Groundwater Quality Data Summary ................................................................................................ 3-33 Phase 3 and Phase 4 Expansions – Design Hydrogeologic Report • Table of Contents iv Appendices Appendix A Bore Logs and Well Construction Diagrams Appendix B Geotechnical Laboratory Data Appendix C Field Notes Appendix D Slug Test Raw Data and Calculations Appendix E Analytical Laboratory Data – August 4, 2016 event Phase 3 and Phase 4 Expansions – Design Hydrogeologic Report • Table of Contents v This page intentionally left blank. 1-1 (revised January 2017) Section 1 Purpose and Scope Rule .0539(d)(3) of the North Carolina Solid Waste Management Rules requires that a Design Hydrogeologic Report be prepared in accordance with the requirements set forth in Rule .0538(b). This document is intended to fulfill all of the specified criteria delineated in this rule. The Design Hydrogeologic Report presented herein is designed to address the applicable Solid Waste Management Rules for the Permit to Construct for the Phase 3 and 4 Expansions of the Cabarrus County Construction & Demolition Debris (C&D) Landfill Facility. Both the Phase 3 and Phase 4 expansions encompass approximately 2 acres and are each designed to provide 5 years of disposal life based on recent disposal rates. The report compiles information from all field activities that have been conducted to date, summarizing data from previously submitted documents, as well as subsequent investigation activities, to provide a comprehensive characterization of the geology and hydrogeology at the landfill site. The goal of this investigation is to provide sufficient technical information to design a Water Quality Monitoring Plan for the Phase 3 and 4 Expansions as specified in Rule .0538(b)(2). 1.1 Report Contents Section 1 of the Design Hydrogeologic Report discusses the purpose and scope of the report, summarizes previous and current investigation activities, and provides a cross-reference between each applicable regulatory requirement set forth in Rule .0538(b) and corresponding sections of this report. Section 2 presents a summary of the methodologies used in this field investigation, as well as data collection and evaluation activities. Section 3 presents the results of this field investigation and data analysis activities. Conclusions derived from this and previous investigations are presented in Section 4, along with a discussion of hydrogeologic factors affecting the landfill design and development of the Water Quality Monitoring Plan. 1.2 Previous Investigations Investigations have been conducted on and adjacent to the proposed site on several occasions since 1993 for a Landfill Expansion Feasibility Study. The Study was done in order to determine the feasibility of expanding the existing landfill property for use in construction of a new Subtitle D lined landfill unit. It was determined that the crystalline rock at the site was shallow in areas and has little inherent porosity The study also determined that the occurrence and movement of groundwater in the bedrock is essentially controlled by openings within the rock mass created by weathering, mass wasting or tectonic processes (fractures). Groundwater level data indicated that the groundwater occurs at the site generally under unconfined conditions in the saprolite and partially weathered rock (PWR), as well as fractures within the less weathered bedrock. Localized semi-confined conditions may also be present within individual fractures or fracture zones depending upon the orientation and extent at which they are interconnected with the saprolite, PWR, or other fractures. Conditions were found to be suitable for Subtitle D landfill development, however, the County chose not to pursue the option. Section 1 • Purpose and Scope 1-2 (revised January 2017) A Groundwater Assessment for the Closed Unit 2 & 3 Landfill was completed in October 2000. Groundwater contamination was found to have extended beyond the 125-foot review boundary. As part of the Assessment, additional groundwater monitoring wells were installed further down- gradient of the compliance wells. Groundwater contamination was found to be localized in the areas around MW-E and MW-A. The site is currently undergoing remediation of contaminated groundwater from the Closed Unit 2/3 MSW landfill. Remediation is being completed by monitored natural attenuation and institutional controls paired with enhanced anaerobic bioremediation. 1.2.1 C&D Landfill Investigation – Phase 1 In November 2002, the feasibility of expansion of a C&D landfill to the west of the closed Unit 2/3 MSW landfill was investigated. Fourteen boreholes were drilled at twelve locations during the investigation. Boreholes were drilled using hollow-stem auger (HSA), air rotary drilling techniques, and conventional rock coring. Rock core samples were taken from B-10 at depths of 21-26 ft and 26-31 ft using conventional rock core techniques. Eight locations, B-1s, B-3, B-5, B-8, B-9, B-10, B-11, and B-12 were characterized using HSA and standard penetration testing (blow counts) with the exception of B-10 where additional conventional rock coring was done after auger refusal. Four locations, B-2, B-4, B-6, and B-7 were characterized using HSA and standard penetration testing, until auger refusal occurred, at which time air rotary drilling was utilized to complete the boring. Air rotary drilling was the only method used at locations B-1d and B-8d. Piezometers were installed in fourteen boreholes at twelve locations, providing two nested piezometer pairs. B-1s and B-1d, and B-8 and B-8d were the shallow and deep piezometers of the two nested pairs. Water level measurements were taken at each of the piezometers at time of boring, 24 hours after boring, during the semi-annual groundwater sampling event, and periodically thereafter. Piezometer measuring points were surveyed to state plane coordinates and mean sea level elevation. Piezometer locations are shown on Figure 1.1. Because of the proximity to the existing landfill and known groundwater contamination associated with the closed landfill, groundwater samples were collected from four piezometers (B-3, B-4, B-5, and B-6) and analyzed for Volatile Organic Compounds (VOCs) and Metals on June 11 and 25, 2003. Based on the groundwater sampling results, it was determined that the groundwater contamination from the old Unit 2/3 landfill was present in the initial proposed expansion area and the feasibility of C&D landfill development in this area was discontinued for the time being. 1.2.2 C&D Landfill Investigation – Phase 2 Since impacted groundwater was detected in the area to the west of the existing landfill, the proposed C&D landfill expansion area was moved to the area to the north of the existing MSW landfill. Several older monitoring wells and piezometers already existed in this area; however, no lithologic, well construction, or survey data was available for most of the existing points. In order to obtain lithology data and supplement groundwater elevation data in the new proposed expansion area, additional borings were required. Section 1 • Purpose and Scope 1-4 (revised January 2017) Prior to drilling any new piezometers in the area, one groundwater sample was collected from piezometer B-12 and analyzed for Volatile Organic Compounds (VOCs) in order to verify that pre- existing groundwater contamination was not present. Piezometer B-12 was installed as part of the original proposed location investigation, but was within the anticipated footprint of the existing C&D landfill. Based on the groundwater sampling results, it was determined that there was no groundwater contamination from the old Unit 2/3 landfill present and the feasibility of C&D landfill development could continue in this area. As part of the investigation, four boreholes were drilled at four locations. Boreholes were advanced using a truck-mounted drill rig utilizing HSA techniques. Piezometers were installed in each borehole. Water level measurements were taken at each of the piezometers at time of boring, 24 hours after boring, and during subsequent events. Both new piezometer measuring points and old existing wells were surveyed to state plane coordinates and mean sea level elevation (MSL). Evaluation of piezometers and monitoring wells in and around the proposed C&D Landfill expansion area suggested that groundwater movement was in a semi-radial pattern from the north, with discharge to the central drainage feature east of the existing C&D landfill. 1.2.3 Monitoring Well Installation In August and September 2006, installation of two background monitoring wells (CD-1s, -1d) and five downgradient compliance wells (CD-2, -3, -4, -5, and -6) for the active C&D Landfill was completed. The deep background well, CD-1d, was converted from piezometer B-13, which was installed during the Phase 2 investigation. Monitoring wells CD-1d, -3, and -5 were installed using HSA and standard penetration testing, until auger refusal occurred, at which time air rotary drilling was utilized to complete the boring. Monitoring wells CD-1s, -2, -4, and -6 were installed utilizing HSA methods and standard penetration testing. The wells were slug tested for estimation of hydraulic conductivity after development, with the exception of CD-1d and CD-6. In addition, each of the wells were surveyed to state plane coordinates and MSL elevation, and sampled. Borelogs, slug test and initial sampling results were forwarded to the SWS in a letter report dated October 11, 2006. However, the installation and sampling of CD-4, -5, and -6 were not discussed in the October 2006 submittal. Based on the groundwater sampling results, it was determined that the groundwater contamination from the closed Unit 2 MSW Landfill was present in the wells. Therefore, through subsequent discussions with the SWS, wells CD-4, -5, and -6 were added to the approved groundwater monitoring network for the closed Unit 2 MSW Landfill to monitor and assess groundwater quality. 1.2.4 C&D Landfill Investigation – Phase 2 Expansion The Phase 2 C&D Landfill expansion area consisted of approximately 2 acres south of the active C&D landfill. As part of the Phase 2 expansion investigation, three boreholes were drilled at 2 locations (B-18s/B-18d, B-19). All borings were converted to piezometers for groundwater elevation measurements and lithologic and geotechnical data was collected at each location. HSA drilling was used for lithologic and geotechnical data collection at each boring. Rock coring was performed at B-18d. Standard penetration tests were taken at all locations. In addition, at the request of the Solid Waste Section, one monitoring well (CD-4 rep) was installed to the northeast Section 1 • Purpose and Scope 1-5 (revised January 2017) of the Phase 1 expansion. CD-4 rep replaces monitoring well CD-4, which along with monitoring well CD-5, was abandoned prior to construction of the Phase 1 expansion. Other piezometers were also installed in the Phase 1 expansion area (B-17s/B-17d). These piezometers have been abandoned, but are referenced for supporting groundwater and lithologic information throughout this report. Water level measurements were taken at each of the piezometers at least seven days after boring and periodically thereafter. Water levels were not taken immediately after installation as the water table had not stabilized after development. Piezometer measuring points were surveyed to state plane coordinates and MSL elevation. 1.2.5 Monitoring Well Installation – Phase 2 Expansion As discussed in the Water Quality Monitoring Plan for the Phase 2 Expansion, monitoring well CD- 3 was abandoned and re-installed approximately 125-feet from the Phase 2 Expansion and piezometers B-7 and B-19 were converted to monitoring wells CD-7 and CD-8, respectively. No new monitoring wells were installed. 1.2.6 Alternate Source Demonstration In September 2013, an Alternate Source Demonstration (ASD) was submitted to the SWS for the area of future C&D expansion south of the active C&D landfill. The ASD concluded that it is apparent that all contamination located in the area adjacent to the existing C&D landfill is due to impact of leachate from the closed unlined Unit 2 & 3 MSW landfill. To date, groundwater monitoring wells immediately downgradient of the existing C&D landfill (CD-2, CD-3, CD-7, and CD-8) have not had detections of any contaminant of concern VOCs above their respective NC2L. 1.3 Current Investigation The current investigation focused on the proposed Phase 3 and 4 C&D Landfill expansion areas south of the existing Phase 2 area of the active C&D landfill. Due to the small size of the Phase 3 and 4 expansion areas and previous hydrogeologic investigations in the area, no additional borings were needed. Within and adjacent to the proposed Phase 3 and 4 expansion areas, there are six existing piezometers (B-1s/1d, B-3, B-6, and B-18s/18d), and four monitoring wells (CD-3, CD-6, CD-7, and CD-8). HSA drilling was used for lithologic and geotechnical data collection at each boring. Rock coring was performed at B-18d. Other piezometers installed in the existing C&D area have been abandoned, but are referenced for supporting groundwater and lithologic information throughout this report. There are also several existing piezometers in potential future expansion areas further south of the Phase 3 and 4 expansion areas. Water level measurements were taken at each of the existing piezometers and monitoring wells and the data was appended to existing measurements from the previous investigations. In addition, groundwater samples were collected from existing piezometers B-1s, B-1d, B-4, B-5, B- 6, B-18s, and B-18d, in order to track groundwater conditions described in the ASD. 2-1 (revised January 2017) Section 2 Methodology This section presents the methodology and data reduction used during the Phase 3 and 4 C&D Landfill expansions hydrogeologic field investigation. As described in Section 1.3, the current investigation water level measurements and groundwater sampling. Due to the small size of the expansion and previous work done in the area, no drilling or piezometer installation was required in the expansion areas. A discussion of methods used for the previous subsurface work in the expansion area are provided below. 2.1 Drilling Methods The following section details the drilling methods used to install borings and piezometers and collect geologic and hydrogeologic data for the Phase 3 and 4 C&D landfill expansions. 2.1.1 Borehole Drilling Borehole drilling methods for this investigation included hollow stem auger (HSA) and conventional rock coring. An onsite hydrogeologist observed the drilling operations and logged the borings. For the purposes of this investigation, the base of the saprolite unit has been defined as the depth at which soil penetration using a split-spoon sampler is greater than 50 blows per 6- inches. This definition is used to permit consistent identification of the saprolite/PWR contact. Boring logs from this and previous investigations within and adjacent to the Phase 3 and 4 expansion areas are provided in Appendix A. 2.1.1.1 Hollow-Stem Auger Drilling Lithologic information was obtained at all locations by HSA drilling methods. All HSA borings in the proposed Phase 3 and 4 expansion areas were advanced to the top of bedrock (auger refusal). An ATV-mounted Diedrich D-50 Turbo drill rig using 8-inch outer diameter augers was used to complete the HSA drilling. Lithologic information was obtained through split-spoon sampling at 5 foot intervals as outlined in ASTM D-1586. Blow counts were noted during the driving of the split- spoon sampler, and the sample was examined by the field hydrogeologist and described for color, grain size, texture, and moisture content. The field descriptions were entered into the field logbook. Borehole logs from HSA drilling are provided in Appendix A. The depth of the first encountered blow count of 50 within a 6-inch interval was used to define the top of PWR, and the depth of auger refusal was used to define the top of bedrock. 2.1.1.2 Rock Coring The Diedrich D-50 Turbo drill rig used for HSA drilling was also used for rock coring. During the investigation, bedrock was cored at B-18d. Standard rock coring techniques were utilized as described below. An HQ size double tube core barrel was attached to the bottom of the drill string and lowered to the bottom of the borehole. The desired coring interval was drilled using a carbide-toothed bit Section 2 • Methodology 2-2 (revised January 2017) and clear, potable water. When the desired interval had been penetrated, the entire core barrel and attached drill string were retrieved from the hole. The inner sample tube was extracted from the outer barrel and the core sample was then extruded and placed into a box labeled with the core ID and depth intervals. The rock core was described in the field and the percent recovery, rock quality designation (RQD), and frequency of fractures were noted. Observed fracture infilling or coatings, gross mineralogy, and other notable characteristics were also recorded. The RQD was determined by dividing the total length of rock fragment longer than four inches over the total core length. Logs of the core borings are contained in Appendix A and discussed further in Section 3.1.1.4. 2.2 Piezometer Installations As discussed in Section 1.3, 6 piezometers were installed at 4 locations and 4 monitoring wells were installed during previous investigations in the Phase 3 and 4 expansion areas. The piezometer and well locations are shown on Figure 1-1 along with those installed in and around the Phase 3 and 4 expansion areas during previous investigations. Table 2-1 provides a summary of piezometer completion data for the piezometers and monitoring wells installed during this and previous investigations. All piezometers and monitoring wells were constructed of 2-inch diameter PVC casing, with 5 or 10-foot, 0.010-inch slot PVC screen and bottom cap. A filter pack consisting of #2 silica sand was placed around the well screen to a minimum of 2 feet above the top of screen. The piezometer annulus above the filter pack was then sealed with a minimum of 2 feet of 3/8-inch hydrated bentonite pellets. The bentonite was allowed to set-up for at least several hours prior to grouting. The remainder of the annulus was then filled with a Portland cement/bentonite grout poured from the surface. Locking steel protective covers with a well ID placard and a 2-foot by 2-foot concrete pad were installed over all piezometers or monitoring wells. 2.3 Water Level Measurements Water level measurements were taken using an electronic water level meter with an accuracy of 0.01 feet. Water level measurements were taken relative to the north side of the top of each PVC well casing (TOC = top of casing). Water levels were monitored both during and after the piezometer completion. Water levels were collected after piezometer completion, when possible, 24 hours after completion, and at least seven days after completion. Measurement of water levels at precise time periods after completion was not always possible due to conflicts with other drilling operations and the expedited nature of the field investigation. However, adequate measurements were taken for the purposes of the installation. Water level measurements are discussed in detail in Section 3.3.1. 2.4 Piezometer Surveying CESI Land Development Services conducted the surveying. All of the piezometers and borings were surveyed to the TOC measuring point and to ground surface. Northing and easting coordinates were reported in the state plane coordinate system, and elevations were surveyed to MSL elevation. Ta b l e 2 - 1 Pi e z o m e t e r a n d M o n i t o r i n g W e l l C o m p l e t i o n S u m m a r y Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n We l l Co m p l e t i o n Da t e Dr i l l i n g Me t h o d Sc r e e n e d I n t e r v a l L i t h o l o g y To p o f P V C El e v a t i o n (f e e t m s l ) Gr o u n d Su r f a c e El e v a t i o n (f e e t m s l ) Bo r e h o l e De p t h (f e e t b l s ) Sc r e e n e d In t e r v a l (f e e t b l s ) To p o f Sc r e e n ( m s l ) Bo t t o m o f Sc r e e n ( m s l ) To p o f Sa n d ( f e e t bl s ) To p o f Se a l ( f e e t bl s ) Bo r e h o l e Dia m e t e r (in c h e s ) Ca s i n g Di a m e t e r (in c h e s ) B- 1 s 11 / 1 8 / 2 0 0 2 HS A Sa p r o l i t e / P W R 74 0 . 2 7 73 8 . 2 5 35 25 . 0 - 3 5 . 0 71 3 . 2 5 70 3 . 2 5 23 21 8 2 B- 1 d 11 / 1 9 / 2 0 0 2 Ai r Be d r o c k 74 0 . 8 7 73 8 . 2 5 52 42 . 0 - 5 2 . 0 69 6 . 2 5 68 6 . 2 5 40 38 6 2 B- 2 11 / 2 5 / 2 0 0 2 HS A / A i r Be d r o c k 75 0 . 9 1 74 8 . 4 0 45 35 . 0 - 4 5 . 0 71 3 . 4 0 70 3 . 4 0 33 31 8/ 6 2 B- 3 11 / 1 8 / 2 0 0 2 HS A PW R 76 1 . 7 6 75 9 . 2 4 57 47 . 0 - 5 7 . 0 71 2 . 2 4 70 2 . 2 4 45 43 8 2 B- 4 11 / 2 5 / 2 0 0 2 HS A / A i r Be d r o c k 75 5 . 7 7 75 4 . 0 3 72 42 . 0 - 6 2 . 0 71 2 . 0 3 69 2 . 0 3 40 38 8/ 6 2 B- 5 11 / 2 1 / 2 0 0 2 HS A PW R 72 2 . 2 3 72 0 . 9 3 26 16 . 0 - 2 6 . 0 69 4 . 9 3 68 4 . 9 3 14 12 8 2 B- 6 11 / 2 5 / 2 0 0 2 HS A / A i r Be d r o c k 76 2 . 6 7 76 1 . 1 7 72 52 . 0 - 7 2 . 0 70 9 . 1 7 68 9 . 1 7 50 48 8/ 6 2 B- 7 ( C D - 7 ) 11 / 2 5 / 2 0 0 2 HS A / A i r Be d r o c k 74 4 . 8 1 74 2 . 1 8 44 34 . 0 - 4 4 . 0 70 8 . 1 8 69 8 . 1 8 32 30 8/ 6 2 B- 8 s 11 / 2 0 / 2 0 0 2 HS A Sa p r o l i t e / P W R 72 5 . 5 7 72 3 . 7 1 21 11 . 0 - 2 1 . 0 71 2 . 7 1 70 2 . 7 1 9 7 8 2 B- 8 d 11 / 1 9 / 2 0 0 2 Ai r Be d r o c k 72 5 . 6 0 72 3 . 3 6 29 19 . 0 - 2 9 . 0 70 4 . 3 6 69 4 . 3 6 17 15 6 2 B- 9 11 / 2 0 / 2 0 0 2 HS A Sa p r o l i t e / P W R 74 2 . 8 2 73 9 . 9 4 30 20 . 0 - 3 0 . 0 71 9 . 9 4 70 9 . 9 4 18 16 8 2 B- 1 0 11 / 2 0 / 2 0 0 2 HS A / C o r e PW R / B e d r o c k 73 8 . 0 1 73 6 . 8 9 31 16 . 0 - 3 1 . 0 72 0 . 8 9 70 5 . 8 9 14 12 8/ 4 2 B- 1 1 11 / 2 0 / 2 0 0 2 HS A Sa p r o l i t e / P W R / B e d r o c k 73 3 . 9 8 73 1 . 8 3 25 15 . 0 - 2 5 . 0 71 6 . 8 3 70 6 . 8 3 13 11 8 2 B- 1 2 11 / 2 2 / 2 0 0 2 HS A Sa p r o l i t e / P W R 74 5 . 1 5 74 3 . 0 8 26 16 . 0 - 2 6 . 0 72 7 . 0 8 71 7 . 0 8 14 12 8 2 B- 1 3 ( C D - 1 d ) 7/ 2 1 / 2 0 0 4 HS A PW R 75 7 . 2 6 75 4 . 0 50 40 . 0 - 5 0 . 0 71 4 . 0 70 4 . 0 38 36 4 2 B- 1 4 7/ 2 1 / 2 0 0 4 HS A Sa p r o l i t e / P W R 75 5 . 0 8 75 2 . 3 37 27 . 0 - 3 7 . 0 72 5 . 3 71 5 . 3 25 23 4 2 B- 1 5 7/ 2 2 / 2 0 0 4 HS A Sa p r o l i t e / P W R 75 6 . 8 0 75 4 . 0 35 25 . 0 - 3 5 . 0 72 9 . 0 71 9 . 0 23 21 4 2 B- 1 6 7/ 2 2 / 2 0 0 4 HS A Sa p r o l i t e / P W R 74 1 . 7 4 73 8 . 7 25 20 . 0 - 2 5 . 0 71 8 . 7 71 3 . 7 18 16 4 2 B- 1 7 s 1/ 1 5 / 2 0 0 9 HS A Sa p r o l i t e / P W R 75 4 . 6 2 75 3 . 5 38 28 . 0 - 3 8 . 0 72 5 . 5 71 5 . 5 26 24 8 2 B- 1 7 d 1/ 1 5 / 2 0 0 9 HS A / C o r e Be d r o c k 75 4 . 6 9 75 3 . 3 47 42 . 0 - 4 7 . 0 71 1 . 3 70 6 . 3 40 38 8/ 4 2 B- 1 8 s 1/ 1 5 / 2 0 0 9 HS A PW R 74 3 . 3 4 74 2 . 1 38 28 . 0 - 3 8 . 0 71 4 . 1 70 4 . 1 26 24 8 2 B- 1 8 d 1/ 1 4 / 2 0 0 9 HS A / C o r e Be d r o c k 74 4 . 0 2 74 1 . 9 49 44 . 0 - 4 9 . 0 69 7 . 9 69 2 . 9 42 40 8/ 4 2 B- 1 9 1/ 1 3 / 2 0 0 9 HS A PW R 74 1 . 2 4 73 9 . 7 43 33 . 0 - 4 3 . 0 70 6 . 7 69 6 . 7 31 29 8 2 CD - 8 7/ 1 / 2 0 1 4 HS A PW R 73 8 . 3 9 73 9 . 0 43 33 . 0 - 4 3 . 0 70 6 . 0 69 6 . 0 31 29 6 2 CD - 1 s 8/ 7 / 2 0 0 6 HS A Sa p r o l i t e 75 5 . 0 75 2 28 18 . 0 - 2 8 . 0 73 4 . 0 72 4 . 0 16 14 8 2 CD - 2 9/ 1 2 / 2 0 0 6 HS A Sa p r o l i t e 73 3 73 0 24 9. 0 - 2 4 . 0 72 1 . 0 70 6 . 0 7 5 8 2 CD - 3 9/ 2 5 / 2 0 0 6 HS A / A i r Sa p r o l i t e / P W R 75 3 . 3 75 0 60 45 . 0 - 6 0 . 0 70 5 . 0 69 0 . 0 43 41 8 2 CD - 3 7/ 1 / 2 0 1 4 HA S / A i r Sa p r o l i t e / P W R 74 4 . 4 8 74 1 50 35 . 0 - 5 0 . 0 70 6 . 0 69 1 . 0 32 30 6 2 CD - 4 8/ 7 / 2 0 0 6 HS A Sa p r o l i t e / P W R 75 5 . 5 75 2 27 17 . 0 - 2 7 . 0 73 5 . 0 72 5 . 0 15 13 8 2 CD - 4 R e p 1/ 1 5 / 2 0 0 9 HS A Sa p r o l i t e 73 9 . 1 5 73 6 . 2 16 6. 0 - 1 6 . 0 73 0 . 2 72 0 . 2 4 2 8 2 CD - 5 9/ 2 5 / 2 0 0 6 HS A / A i r Sa p r o l i t e / P W R 75 8 . 7 75 5 60 45 . 0 - 6 0 . 0 71 0 . 0 69 5 . 0 43 41 8 2 CD - 6 9/ 1 1 / 2 0 0 6 HS A Sa p r o l i t e / P W R 74 1 . 4 73 8 40 25 . 0 - 4 0 . 0 71 3 . 0 69 8 . 0 23 21 8 2 MW - 2 10 / 6 / 1 9 8 7 HS A PW R 73 3 . 7 8 73 2 . 6 4 40 30 . 0 - 4 0 . 0 70 2 . 6 4 69 2 . 6 4 29 27 6 2 MW - A 9/ 1 6 / 1 9 9 4 HS A / A i r PW R / B e d r o c k 74 6 . 8 0 74 4 . 5 1 50 33 . 0 - 4 8 . 0 71 1 . 5 1 69 6 . 5 1 31 29 6 2 MW - J 9/ 3 / 1 9 9 9 Ai r Be d r o c k 72 8 . 4 7 72 5 . 5 5 32 29 . 0 - 3 2 . 0 69 6 . 5 5 69 3 . 5 5 28 25 6 2 MW - X 12 / 2 0 / 1 9 9 3 HS A / A i r Be d r o c k 71 0 . 2 8 70 8 . 1 5 30 20 . 0 - 3 0 . 0 68 8 . 1 5 67 8 . 1 5 18 16 6 2 P- 4 NA HS A Sa p r o l i t e 73 6 . 1 1 73 4 . 9 10 5. 0 - 1 0 . 0 * 72 9 . 9 72 4 . 9 NA NA NA 2 P- 8 NA HS A Sa p r o l i t e 74 2 . 0 1 73 8 . 9 12 7. 0 - 1 2 . 0 * 73 1 . 9 72 6 . 9 NA NA NA 2 M- 4 NA HS A Sa p r o l i t e 75 4 . 0 7 75 1 . 9 34 24 . 0 - 3 4 . 0 * 72 7 . 9 71 7 . 9 NA NA NA 2 No t e s : Pi e z o m e t e r s i n it a l i c h a v e b e e n a b a n d o n e d . Pi e z o m e t e r s i n bo l d a r e w i t h i n P h a s e 3 a n d 4 e x p a n s i o n a r e a s a n d w i l l b e a b a n d o n e d p r i o r t o c o n s t r u c t i o n . *- A s s u m e d s c r e e n i n t e r v a l . NA - D a t a u n k n o w n . N o b o r e l o g o r w e l l c o n s t r u c t i o n d a t a a v a i l a b l e . U s e d f o r g r o u n d w a t e r e l e v a t i o n d a t a o n l y . B- 1 9 a n d C D - 3 a b a n d o n e d d u r i n g P h a s e 2 e x p a n s i o n a c t i v i t e s a n d r e - l o c a t e d a t C D - 8 a n d C D - 3 . Ta b l e 2 - 1 Section 2 • Methodology 2-4 (revised January 2017) 2.5 Slug Tests Slug tests were not performed on the borings in the Phase 3 and 4 expansion areas. However, slug testing was performed on two piezometers installed within the Phase 1 expansion area (B-17s and B-17d) and CD-4 rep. Both slug-in (displacement) and slug-out (recovery) tests were conducted at each piezometer using a stainless steel solid slug and a transducer/data logger. The transducer/data logger was lowered to approximately 10 to 15 feet below the water level in the piezometer, taped into place, and a reference water level was collected. Immediately after starting the data logger, the slug was lowered to approximately 1.5 feet below the water surface and taped into place. The data logger was then monitored until water levels stabilized. The data logger was then re-started for the slug-out test and the slug was immediately withdrawn from the piezometer. The data logger was monitored until the water level stabilized. The data was then analyzed using the Bouwer and Rice method (Bouwer, 1989) to estimate horizontal hydraulic conductivity. Slug test results are discussed in Section 3.3.2. 2.6 Geotechnical Testing Undisturbed Shelby tube, jar samples and bulk samples collected during this investigation were analyzed for various geotechnical properties by Geotechnics geotechnical laboratory in Raleigh, North Carolina. The testing program consisted of analyses for grain size distribution, soil classification, Atterberg limits, porosity and in-situ and remolded hydraulic conductivity. Laboratory geotechnical data from the samples collected during this and previous investigations in and adjacent to the Phase 3 and 4 expansion areas are presented in Appendix B. Geotechnical testing results for samples collected during this investigation are discussed in Section 3.2. 3-1 (revised January 2017) Section 3 Current Investigation Results This section presents the results of the proposed Phase 3 and 4 expansion investigation areas which included borehole drilling, rock coring, geotechnical testing, piezometer installations, water level measurements, and aquifer characterization (slug testing). The regional geology and hydrogeology have been previously discussed in the existing C&D landfill Design Hydrogeologic Report (CDM, 2005), and, therefore, will not be re-iterated in this report. The site geology and drilling observations are discussed in Section 3.1. Laboratory testing results are discussed in Section 3.2. The site hydrogeology is evaluated in detail in Section 3.3 and includes water level results, potentiometric surface mapping, slug test analysis, and groundwater sampling analysis. Section 3.4 presents a hydrogeologic conceptual model for the site with hydrogeologic cross sections and discussions on groundwater recharge and discharge. 3.1 Site Geology Based on regional mapping of the Charlotte 1°x 2° quadrangle and geological mapping and data collection during this and previous subsurface explorations at the site, metamorphosed quartz diorite is the dominant bedrock lithology at the site. The metamorphosed quartz diorite is interlayered with schistose material and exhibits variable micaceous foliation. Natural processes have weathered the bedrock by chemical alteration of the rock minerals to form saprolite that extends to varying depths below the ground surface. The texture and depth of saprolite development varies with the degree of weathering, which in turn, is related to the mineralogic composition and structure of the native material (Gair, 1989) (CDM, 2005). Intrusive veins and irregularly shaped bodies of quartz and coarse-grained pegmatite ranging from less than 1-inch to a few feet in thickness are frequently observed in the metamorphosed quartz diorite. The quartz is rarely weathered but disaggregates to angular fragments of sand to boulder size. Feldspars in the pegmatic materials are typically altered by weathering to white, plastic clay. During past investigations of the site, a magnetic geophysical survey detected a previously unknown diabase dike approximately 3,500-feet south of the existing C&D Landfill. The dike is trending in a north-west/south-east direction, but does not appear to affect the landfill site. 3.1.1 Drilling Observations Four major lithologic distinctions have been made at the C&D Landfill expansion area based on observations from the previous subsurface investigations. These are: Residuum; saprolite; PWR; and bedrock. Descriptions of each material encountered at specific boring locations are provided in the boring logs contained in Appendix A. Each of these units is discussed in the following sections of the report. Table 3-1 lists all of the borings drilled at the C&D Landfill area and the depths at which the partially weathered rock and bedrock units were encountered. Table 3-1 Summary of Lithologic Data Cabarrus County Construction and Demolition Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Borehole Ground Surface Elev. (feet msl) Depth to PWR (feet bgs) PWR Elevation (feet msl) Depth to Bedrock (feet bgs) Bedrock Elevation (feet msl) B-1 738.25 34 704 35 703 B-2 748.40 25 723 34 714 B-3 759.24 40 719 57 702 B-4 754.03 35 719 40 714 B-5 720.93 10 711 26 695 B-6 761.17 35 726 54 707 B-7 (CD-7)742.18 25 717 35 707 B-8s 723.71 20 704 21 703 B-9 739.94 25 715 30 710 B-10 736.89 20 717 21 716 B-11 731.83 25 707 25 707 B-12 743.08 20 723 26 717 B-13/CD-1 754.0 25 729 >50 >704 B-14 752.3 15 737 >37 >715 B-15 754.0 29 725 >35 >719 B-16 738.7 24 715 >25 >713 B-17 753.5 24 730 39 715 B-18 742.1 28 714 38 704 B-19 (CD-8)739.7 34 706 44 696 CD-2 730 25 705 >25 >705 CD-3 750 25 725 60 690 CD-4 752 20 732 >28 >732 CD-4 rep 736.2 15 721 >16 >721 CD-5 755 33 722 58 697 CD-6 738 23 715 40 698 MW-A 744.5 22 723 48 697 MW-J 725.6 14 712 26 700 MW-X 708.2 4 704 12 696 MW-2 732.6 22 711 >40 >692 Table 3-1 Section 3 • Current Investigation Results 3-3 (revised January 2017) 3.1.1.1 Residuum Generally, the top two to six feet of soil at the site are described as residuum and consist of finer grained materials than the material below. The shallower, finer grained soils are typically described as red or orange clay or silts with little to no sand. The residuum was not present at all locations due to previous site activities in these areas. 3.1.1.2 Saprolite Below the residuum, saprolite is present at all boring locations. These soils are derived from the in-place chemical weathering of bedrock materials, and are characterized by the presence of relict mineral fabric from the original rock mass. These soils typically become more dense and coarser in texture as weathering decreases with depth. Most on-site saprolite soils grade to a silty sand with depth. Saprolite within the proposed expansion areas was observed to be dry to moist at most locations, but was wet near the PWR contact in some borings. Hard rock fragments, particularly quartz, are commonly present in the lower portion of the saprolite and become larger and more frequent with depth. The contact between the saprolite and underlying PWR or bedrock is gradational. The saprolite soils vary from reddish brown to white in color. As noted previously, for the purposes of this investigation, the base of the saprolite unit has been defined as the depth at which soil penetration using a split-spoon sampler is greater than 50 blows per 6-inches. This definition is used to permit consistent identification of the saprolite/PWR contact. Comparing lithologic data from piezometers within and adjacent to the proposed C&D Landfill expansion phases, saprolite was observed to range in thickness from 4 feet at MW-X to 40 feet at B-3, and averaged about 24 feet. Within the proposed Phase 3 and 4 C&D Landfill expansion areas, saprolite ranges from approximately 20 feet in thickness at CD-6 to approximately 34 feet in thickness at B-1, and averaged about 25 feet in thickness. 3.1.1.3 Partially Weathered Rock The PWR elevation and depth below ground surface for each boring in the C&D Landfill expansion area is presented in Table 3.1. At most locations, the saprolite transitionally grades into the parent bedrock from which it is derived. This transition zone has been designated the PWR unit. It is characterized by deeply weathered bedrock material that can be penetrated by augers but requires more than 50 blows to advance a split-spoon sampler 6-inches. The PWR at the proposed C&D Landfill expansion consists primarily of gray to brown/white/tan silty sands to sand in some areas. The PWR was observed to be moist to wet at all locations within the Phase 3 and 4 expansion areas. The PWR thickness within the proposed C&D Landfill expansion area ranges from approximately 1 foot at B-1 to 35 feet at CD-3. The average thickness within the Phase 3 and 4 expansion areas is approximately 15 feet. In most cases, the transition from silty/clayey saprolite to bedrock is relatively thick with the exception of borings located within borrow areas or drainage features. 3.1.1.4 Bedrock The 284.5 acre parcel of land owned by Cabarrus County is underlain by metamorphosed quartz diorite. Bedrock lithology in the C&D Landfill area was consistent with the drilling observations Section 3 • Current Investigation Results 3-4 (revised January 2017) and geologic mapping in the previous site investigations. Within the proposed Phase 3 and 4 expansion areas, depth from ground surface to the top of bedrock ranged from 35 feet at B-1 to 60 feet at CD-3. The average depth to bedrock is approximately 45 feet over the entire proposed C&D Landfill expansion area (existing C&D landfill and proposed future expansion areas). The depth to bedrock is generally shallow in drainage features and significantly deeper in the upland areas. Figure 3-1 is a contour map of the bedrock surface developed from depth to bedrock measurements observed in the exploratory borings drilled in and adjacent to the proposed C&D Landfill expansion areas. It shows that the bedrock surface over most of the site is a subdued reflection of surficial topography. During the previous C&D Landfill design hydrogeologic investigations, one rock core was collected at B-10. Bedrock was encountered at approximately 21 feet below land surface and was described as metamorphosed quartz diorite. Two five-foot core runs were collected and indicated that the top 10 feet of rock were moderately fractured. Recovery values for the two runs were 48 and 50 percent, respectively. RQD values were 25 and 40 percent, respectively. Rock cores were collected during subsequent investigations from B-17d and B-18d. Bedrock was encountered at approximately 38 and 39 feet, respectively, below land surface and was described as metamorphosed quartz diorite. Two five-foot coring runs were collected from each location. Recovery values for the two runs at B-17d were 100 and 98 percent, respectively and RQD values were 26 and 74 percent, respectively. Recovery values for the two runs at B-18d were 92 and 64 percent, respectively and RQD values were 58 and 35 percent, respectively. Observations from the rock cores collected during previous investigations from borings B-10, B- 17d, and B-18d generally showed a moderately fractured top 5 feet of bedrock with red and orange oxidation, likely iron or manganese oxides, observed between fractures. The oxidized fractures are indicative of water movement between the fractures. A summary of the rock core observations from the entire site is presented in Table 3-2. C A B A R R U S C O U N T Y N O R T H C A R O L I N A P H A S E I I I & I V U N L I N E D C & D L A N D F I L L E X P A N S I O N C A B A R R U S C O U N T Y C & D L A N D F I L L N XREFs: [CE_SURVEY, RC01STPL, RC09STPL] Images: []Last saved by: KOSKIAR Time: 1/4/2017 7:54:40 AMpw:\\DACPWAPP2:PW_PL1\1278\114357\04 Design Services NM_30%\02 Civil\10 CADD\FIG-3-1.dwg F I G U R E B E D R O C K C O N T O U R M A P D E S I G N H Y D R O G E O L O G I C I N V E S T I G A T I O N 3 - 1 Ta b l e 3 - 2 Su m m a r y o f R o c k C o r e O b s e r v a t i o n s Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n Bo r i n g Co r e R u n De p t h Re c o v e r y RQ D Ma t e r i a l D e s c r i p t i o n (f e e t ) (% ) (% ) In i t i a l C & D L a n d f i l l A r e a B- 1 0 21 . 0 - 2 6 . 0 48 25 Me t a m o r p h o s e d Q u a r t z D i o r i t e 26 . 0 - 3 1 . 0 50 40 Me t a m o r p h o s e d Q u a r t z D i o r i t e C& D L a n d f i l l P h a s e 1 E x p a n s i o n A r e a B- 1 7 d 38 . 0 - 4 3 . 0 10 0 26 Me t a m o r p h o s e d Q u a r t z D i o r i t e 43 . 0 - 4 8 . 0 98 74 Me t a m o r p h o s e d Q u a r t z D i o r i t e C& D L a n d f i l l P h a s e 3 E x p a n s i o n A r e a B- 1 8 d 39 . 0 - 4 4 . 0 92 58 Me t a m o r p h o s e d Q u a r t z D i o r i t e 44 . 0 - 4 9 . 0 64 35 Me t a m o r p h o s e d Q u a r t z D i o r i t e Ta b l e 3 - 2 Section 3 • Current Investigation Results 3-7 (revised January 2017) 3.2 Testing Program Table 3-3 summarizes the results of the geotechnical testing performed on samples in and around the proposed Phase 3 and 4 expansion areas during previous investigations. The following sections discuss Standard Penetration (SPT), particle size, soil classification (USCS), formation descriptions, and saturated hydraulic conductivity, porosity, effective porosity, and dispersive characteristics for each unit of the uppermost aquifer at the expansion site. 3.2.1 Standard Penetration Testing Standard Penetration Testing (SPT), in accordance with ASTM Standard D1586, was conducted at all boring locations during this investigation. SPT’s were conducted over 2-foot intervals, typically every 5-feet from ground surface to the termination of the boring. Blow counts were recorded for every 6-inches and recorded. The split spoon sample was placed in a sealed glass jar and labeled by boring number, sample number, depth interval, and blow count. Blow counts are presented on the boring logs in Appendix A. 3.2.2 Particle Size Analysis and Unified Soil Classification Within the proposed Phase 3 and 4 expansion areas, 2 split-spoon, 2 Shelby Tube, and 1 bulk sample were submitted for laboratory analysis for grain size, USCS classification, natural moisture content, and Atterberg limits. USCS classifications ranged from ML in B-18 (13-15) to SM in B-18 (21-23). Natural moisture content values ranged from 14% in B-18 (21-23) to 28% in B-19 (4-6). A summary of the geotechnical laboratory results is provided on Table 3-3. Copies of the laboratory data for the samples collected from the Phase 3 and 4 areas during the previous investigation are provided in Appendix B. 3.2.3 Formation Descriptions Formation descriptions were made in the field during drilling by an on-site geologist or geotechnical engineer. Formation descriptions were made according to moisture content, consistency, color, and grain size. Alterations to the field descriptions, where necessary, were made according to the geotechnical laboratory results. Boring logs are provided in Appendix A. Copies of the field notes for the previous investigation are provided in Appendix C. 3.2.4 Geotechnical Laboratory Testing The following section provides laboratory analysis data for hydraulic conductivity, porosity, and effective porosity. Porosity and hydraulic conductivity values were obtained from 2 Shelby Tube and 1 remolded samples collected from the Phase 3 expansion area during previous investigations. Porosity values in the Shelby Tube samples ranged from 37% in B-18 (21-23) to 48% in B-19 (4-6). The undisturbed hydraulic conductivity value ranged from 3.6x10-5 cm/sec in B-19 (4-6) to 8.9x10-6 cm/sec in B-18 (21-23). The average undisturbed hydraulic conductivity across the entire site is 9.6x10-6 cm/sec. Permeability value in the remolded sample from B-18 (0-10) was 1.6x10-7 cm/sec. The average remolded permeability value in samples across the entire site is 5.57x10-7 cm/sec. Ta b l e 3 - 3 Su m m a r y o f G e o t e c h n i c a l T e s t i n g R e s u l t s Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n Es t i m a t e d U n d i s t u r b e d R e m o l d e d At t e r b e r g L i m i t s Bo r i n g N o . D e p t h L i t h o l o g y Sa m p l e U S C S N a t u r a l P o r o s i t y E f f e c t i v e H y d r a u l i c H y d r a u l i c (f e e t ) Ty p e C l a s s i f i c a t i o n M o i s t u r e ( % ) P o r o s i t y C o n d u c t i v i t y C o n d u c t i v i t y L i q u i d P l a s t i c P l a s t i c i t y Co n t e n t (% ) (c m / s e c ) (c m / s e c ) Lim i t Li m i t In d e x B- 1 3 8 . 0 - 1 0 . 0 S a p r o l i t e S p l i t S p o o n S C 7. 2 25 32 2 3 9 B- 1 4 3. 0 - 5 . 0 R e s i d u u m S p l i t S p o o n C H 2 0 . 2 4 64 3 0 3 4 B- 1 4 1 5 . 0 - 1 7 . 0 PW R UD CL 1 1 . 3 7 34 1 9 1 5 B- 1 5 8 . 0 - 1 0 . 0 PW R UD SM 8. 6 8 NP N P N P B- 1 6 1 0 . 0 - 1 2 . 0 S a p r o l i t e UD MH 2 3 . 7 5 65 3 4 3 1 B- 1 7 4. 0 - 6 . 0 F i l l / R e s i d u u m S p l i t S p o o n C H 2 5 . 3 <1 59 2 9 3 0 B- 1 7 8 . 0 - 1 0 . 0 S a p r o l i t e UD ML 2 5 . 9 4 0 . 0 5 1 . 5 0 E - 0 6 36 3 4 2 B- 1 7 1 4 . 0 - 1 6 . 0 S a p r o l i t e S p l i t S p o o n S M 11 24 31 2 6 5 B- 1 7 2 9 . 0 - 3 1 . 0 PW R Sp l i t S p o o n S M 1 4 . 1 6 35 2 8 7 B- 1 7 0 . 0 - 1 0 . 0 F i l l / R e s i d u u m / S a p r o l i t e B u l k MH <1 5. 1 0 E - 0 7 5 5 3 0 2 5 B- 1 8 13 . 0 - 1 5 . 0 S a p r o l i t e S p l i t S p o o n M L 1 8 . 4 13 38 3 2 6 B- 1 8 21 . 0 - 2 3 . 0 S a p r o l i t e UD SM 14 3 7 . 0 2 5 8 . 9 0 E - 0 6 36 3 1 5 B- 1 8 33 . 0 - 3 5 . 0 PW R Sp l i t S p o o n M L 1 0 . 8 21 27 2 4 3 B- 1 8 0. 0 - 1 0 . 0 F i l l / S a p r o l i t e Bu l k ML <1 1. 6 0 E - 0 7 4 7 2 8 1 9 B- 1 9 4. 0 - 6 . 0 R e s i d u u m / S a p r o l i t e U D ML 28 4 8 . 0 1 8 3 . 6 0 E - 0 5 43 3 6 7 CD - 4 r e p 2 . 0 - 4 . 0 S a p r o l i t e UD CL 2 0 . 9 3 8 . 0 1 0 7 . 3 0 E - 0 6 48 2 7 2 1 CD - 4 r e p 4 . 0 - 6 . 0 S a p r o l i t e S p l i t S p o o n S M 1 4 . 7 14 35 2 5 1 0 MW - A 3 . 0 - 5 . 0 R e s i d u u m UD 15 . 3 3 9 . 6 MW - B 3 . 0 - 5 . 0 R e s i d u u m UD 20 . 3 4 2 . 7 MW - X 0 - 5 . 0 R e s i d u u m / S a p r o l i t e B u l k S M - C L 1 4 . 9 2 7 . 4 1. 0 E - 0 6 P- 2 4 19 . 0 - 2 1 . 0 Sa p r o l i t e UD 30 . 2 28 . 0 3. 7 0 E - 0 6 Av e r a g e 17 . 2 3 9 . 2 9 . 6 4 E - 0 6 5 . 5 7 E - 0 7 Ge o m e t r i c M e a n 15 . 9 3 8 . 6 4 . 2 1 E - 0 6 4 . 3 4 E - 0 7 Ta b l e i n c l u d e s b o r i n g s i n a n d a r o u n d C & D e x p a n s i o n s i t e . US C S - U n i f i e d S o i l C l a s s i f i c a t i o n S y s t e m UD - U n d i s t u r b e d S a m p l e ( S h e l b y T u b e ) PW R - P a r t i a l l y w e a t h e r e d r o c k *B e d r o c k p o r o s i t y v a l u e s e s t i m a t e d f o r F r a c t u r e d c r y s t a l l i n e r o c k a s r e p o r t e d b y D r i s c o l l 1 9 8 6 ( p . 6 7 ) P- 2 4 i n s t a l l e d i n 1 9 9 4 F e a s i b i l i t y S t u d y . - B l a n k s i n d i c a t e n o t c a l c u l a t e d Ta b l e 3 - 3 Section 3 • Current Investigation Results 3-9 (revised January 2017) Porosity values were calculated from the initial void ratio by using the equation: n= e/(1+e) where: n = porosity e = void ratio Values for effective porosity (ne) for these samples were estimated based on the grain size analyses applied to the soil classification triangle which illustrates the relationship between grain size and specific yield values (Johnson, 1967). Within the proposed expansion area, estimated effective porosity values ranged from 13% in the sandy silt saprolite (B-18 13-15) to 25% in the silty sand saprolite (B-18 21-23). Table 3-3 presents a summary of the results of the geotechnical laboratory testing for the previous investigations. 3.2.5 Dispersive Characteristics Estimates were made for longitudinal and transverse dispersivity for the uppermost aquifer at the site, which in this case is the saturated saprolite and PWR. Using an equation provided by the Solid Waste Section, longitudinal dispersivity (Dl) was estimated by the following calculation: Dl= C x L x Kdh nedl where: C = Constant (0.1) L = Length to compliance boundary K = hydraulic conductivity dh/dl = hydraulic gradient ne = effective porosity For this estimation, an average hydraulic conductivity value of 5.18x10-5 cm/sec (0.37 ft/day) was used. This value represents the average K of the piezometers installed during the current and previous investigations, based on slug test analyses. An average hydraulic gradient of 0.02 ft/ft was used. This value represents measurements collected from piezometers installed in and adjacent to the expansion areas during the current investigation. An average effective porosity of 14% was used. This value represents the average estimated effective porosity from samples collected from the saprolite and PWR. A length of 250 feet was used. This value represents the distance from the edge of waste to the compliance boundary. Using the estimations and calculation described above, an average longitudinal dispersivity of 1.3 ft was determined. Assuming that transverse dispersivity is 10% of longitudinal dispersivity, transverse dispersivity was estimated at 0.13 ft. Section 3 • Current Investigation Results 3-10 (revised January 2017) Longitudinal dispersivity was also estimated using an EPA calculator. Assuming a plume length of 250 feet, longitudinal dispersivity ranged from 0.41 ft to 1500 ft. And by using the formula from Xu and Eckstein (1995) on the EPA site, assuming a plume length of 250 feet, a longitudinal dispersivity of 12.5 ft was determined. Therefore, transverse dispersivity ranges from 0.041 ft to 150 ft. 3.3 Site Hydrogeology Results of investigation activities designed to characterize the hydrogeology beneath the Site are presented in this section. These activities included water level measurements and aquifer slug testing. 3.3.1 Water Level Measurements Water level measurements collected from the piezometers installed during previous investigations are provided in Table 3-4. These include measurements taken at least seven days after installation and ranges from November 2002 to August 4, 2016. Water levels were not taken after installation as stabilization after development had not occurred. The water level measurements taken during the August 4, 2016 event were used to construct the potentiometric contour map presented on Figure 3-2. Since installation, water table elevations have remained fairly constant. Table 3-4 also includes the highest recorded elevations for the piezometers and the monitoring wells installed during previous investigations. This includes water level measurements dating back to November 2002. Table 3-5 provides water level measurements for all monitoring wells at the adjacent Closed facility. 3.3.1.1 Horizontal and Vertical Gradients Horizontal Gradients Figure 3-2 presents a potentiometric surface contour map for the C&D Landfill Phase 3 and 4 expansion areas and adjacent areas. This map was constructed from water level data collected during the August 4, 2016 event. The contour map shows that the potentiometric surface, similar to the bedrock surface, is a subdued reflection of surface topography. Topographic divides are generally also groundwater divides and groundwater flow converges into the primary and secondary drainage features within the proposed C&D expansion areas. Groundwater flows radially away from topographically high areas. On the steep slopes, the hydraulic gradient steepens. The horizontal gradient within the Phase 3 and 4 areas from CD-1s toward B-18s was approximately 0.023 feet/foot (ft/ft). The horizontal gradient from B-18 toward the western drainage feature near MW-X was approximately 0.006 ft/ft. Previous gradient values across the proposed expansion areas averaged approximately 0.02 ft/ft. The 0.02 ft/ft values were used in velocity calculations for conservancy. Ta b l e 3 - 4 Wa t e r L e v e l M e a s u r e m e n t s Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n We l l To p o f C a s i n g Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Wa t e r L e v e l Es t i m a t e d Es t i m a t e d Ele v a t i o n (M S L ) 11 / 2 5 / 2 0 0 2 (M S L ) 6/ 1 1 / 2 0 0 3 (M S L ) 6/ 2 5 / 2 0 0 3 (M S L ) 7/ 7 / 2 0 0 4 (M S L ) 7/ 1 6 / 2 0 0 4 (M S L ) 7/ 2 8 / 2 0 0 4 (M S L ) 8/ 1 0 / 2 0 0 4 (M S L ) 8/ 2 4 / 2 0 0 4 (M S L ) 11 / 1 9 / 2 0 0 4 (M S L ) 1/ 1 3 / 0 5 (M S L ) 1/ 2 2 / 0 9 (M S L ) 2/ 1 2 / 0 9 (M S L ) 6/ 3 0 / 0 9 (M S L ) 3/ 2 2 / 1 2 (M S L ) 5/ 3 / 1 2 (M S L ) 8 / 4 / 1 6 ( M S L ) Se a s o n a l Hig h Ele v a t i o n LT S e a s o n a l Hi g h Ele v a t i o n B- 1 D 74 0 . 8 7 70 4 . 5 7 71 0 . 9 8 71 1 . 4 9 70 7 . 9 4 70 7 . 8 7 70 7 . 7 7 70 7 . 6 6 70 7 . 5 3 70 7 . 5 7 70 7 . 4 5 70 5 . 0 2 70 5 . 1 2 70 6 . 6 0 70 4 . 3 3 70 4 . 6 4 70 6 . 6 9 71 4 . 9 9 71 6 B- 1 S 74 0 . 2 7 70 5 . 3 7 71 1 . 1 0 71 1 . 5 4 70 7 . 9 9 70 7 . 8 8 70 7 . 7 7 70 7 . 7 4 70 7 . 5 8 70 7 . 2 7 70 7 . 5 0 70 5 . 0 4 70 5 . 1 3 70 6 . 6 3 70 4 . 3 3 70 4 . 7 3 70 6 . 7 2 71 5 . 0 4 71 6 B- 2 75 0 . 9 1 71 3 . 4 1 71 4 . 2 4 71 7 . 7 3 71 6 . 5 1 71 6 . 4 1 71 6 . 3 1 71 6 . 2 6 71 6 . 0 5 71 6 . 0 9 71 5 . 4 9 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 1 . 2 3 72 2 B-3 76 1 . 7 6 70 4 . 2 6 70 8 . 4 3 70 8 . 5 6 70 6 . 9 9 71 0 . 0 2 70 6 . 9 2 70 6 . 9 4 70 6 . 7 9 70 7 . 1 1 70 6 . 5 0 70 3 . 9 1 70 4 . 0 0 70 4 . 9 2 70 3 . 4 3 70 3 . 6 4 70 5 . 3 7 71 3 . 5 2 71 5 B- 4 75 5 . 7 7 70 1 . 6 7 70 5 . 7 3 70 5 . 3 2 70 4 . 9 7 70 4 . 8 7 70 4 . 8 2 70 4 . 7 7 70 4 . 6 0 70 4 . 5 9 70 4 . 3 9 70 3 . 2 3 70 3 . 3 8 70 5 . 2 1 70 4 . 9 6 70 5 . 1 0 70 5 . 8 5 70 9 . 3 5 71 0 B- 5 72 2 . 2 3 70 1 . 5 3 70 3 . 7 1 70 3 . 5 6 70 3 . 2 0 70 3 . 0 3 70 3 . 0 3 70 2 . 8 8 70 2 . 7 9 70 2 . 5 0 70 3 . 3 3 70 2 . 5 3 70 2 . 3 5 70 3 . 2 1 70 3 . 0 7 70 2 . 3 3 70 3 . 0 4 70 7 . 2 1 70 8 B-6 76 2 . 6 7 70 6 . 8 7 71 0 . 4 8 71 1 . 8 5 70 9 . 5 3 -- 70 9 . 3 9 70 9 . 2 7 70 9 . 2 0 70 8 . 9 9 70 8 . 8 4 70 6 . 6 0 70 6 . 6 4 70 7 . 4 5 70 6 . 6 6 70 6 . 9 4 70 8 . 2 0 71 5 . 3 5 71 6 B- 7 ( C D - 7 ) 74 4 . 8 1 70 4 . 5 1 70 8 . 7 9 70 8 . 8 9 70 6 . 1 5 70 5 . 0 8 70 6 . 0 1 70 5 . 9 8 70 5 . 9 0 70 6 . 6 6 70 5 . 8 7 70 4 . 3 2 70 4 . 3 3 70 4 . 7 0 70 3 . 7 4 70 3 . 8 6 70 5 . 0 4 71 2 . 3 9 71 3 B-8 D 72 5 . 6 0 72 3 . 3 0 72 4 . 8 5 72 4 . 4 7 72 2 . 2 8 72 2 . 2 0 72 2 . 2 5 72 1 . 3 0 71 6 . 1 4 72 2 . 3 7 72 2 . 3 0 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 4 . 8 5 72 5 B- 8 S 72 5 . 5 7 72 3 . 0 7 72 4 . 0 1 72 3 . 8 9 72 1 . 8 5 72 1 . 6 3 72 1 . 8 9 72 0 . 8 2 72 0 . 9 4 72 2 . 0 0 72 2 . 7 7 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 4 . 0 1 72 4 B- 9 74 2 . 8 2 72 0 . 5 2 72 6 . 7 3 72 7 . 0 8 72 4 . 9 0 -- 72 4 . 4 6 NM 72 4 . 0 2 72 3 . 7 0 72 3 . 9 6 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 0 . 5 8 73 2 B- 1 0 73 8 . 0 1 73 1 . 5 1 73 3 . 2 2 73 2 . 5 2 72 8 . 8 8 72 7 . 3 3 72 7 . 4 8 72 6 . 5 0 72 6 . 3 3 72 8 . 4 6 72 8 . 8 6 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 6 . 7 2 73 7 B- 1 1 73 3 . 9 8 71 4 . 9 8 71 5 . 8 7 72 0 . 8 7 72 0 . 0 4 71 9 . 7 1 71 9 . 7 0 71 9 . 3 1 71 9 . 1 5 71 9 . 7 1 72 0 . 2 2 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 4 . 3 7 72 5 B- 1 2 74 5 . 1 5 72 7 . 9 5 73 1 . 3 9 73 4 . 3 1 72 8 . 4 1 72 8 . 0 8 72 7 . 9 3 72 7 . 6 2 72 7 . 3 3 72 7 . 9 5 72 9 . 0 2 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 7 . 8 1 73 9 B- 1 3 75 7 . 2 6 -- -- -- -- -- 73 4 . 5 1 73 4 . 6 8 73 4 . 5 2 73 4 . 2 6 73 2 . 5 9 * * * * * * 73 8 . 1 8 73 9 B- 1 4 75 5 . 0 8 -- -- -- -- -- 72 8 . 3 8 73 4 . 1 2 73 3 . 9 6 73 3 . 8 3 73 4 . 0 8 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 7 . 6 2 73 9 B- 1 5 75 6 . 8 0 -- -- -- -- -- 73 1 . 7 0 73 2 . 4 5 73 2 . 3 5 73 2 . 6 8 73 3 . 0 0 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 6 . 5 0 73 8 B- 1 6 74 1 . 7 4 -- -- -- -- -- 73 1 . 0 9 73 1 . 9 4 NM 73 2 . 3 9 73 2 . 5 3 73 0 . 6 1 73 0 . 6 2 73 0 . 3 3 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 6 . 0 3 73 7 B- 1 7 s 75 4 . 6 2 -- -- -- -- -- -- -- -- -- -- 72 2 . 7 1 72 2 . 6 5 72 3 . 1 0 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 6 . 6 0 72 8 B- 1 7 d 75 4 . 6 9 -- -- -- -- -- -- -- -- -- -- 72 2 . 8 2 72 2 . 7 3 72 3 . 2 1 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 6 . 7 1 72 8 B- 1 8 s 74 3 . 3 4 -- -- -- -- -- -- -- -- -- -- 70 5 . 1 6 70 5 . 1 7 70 6 . 3 2 70 4 . 6 0 70 4 . 8 0 70 6 . 3 8 70 9 . 8 8 71 1 B-1 8 d 74 4 . 0 2 -- -- -- -- -- -- -- -- -- -- 70 5 . 1 7 70 5 . 1 9 70 6 . 3 4 70 4 . 5 9 70 4 . 8 4 70 6 . 4 3 70 9 . 9 3 71 1 B- 1 9 74 1 . 2 4 -- -- -- -- -- -- -- -- -- -- 70 4 . 9 4 70 4 . 9 1 70 6 . 0 4 70 4 . 2 9 70 4 . 4 7 Ab a n d o n e d 70 9 . 5 4 71 1 CD - 8 73 8 . 3 9 -- -- -- -- -- -- -- -- -- -- 70 6 . 4 7 70 9 . 9 7 71 1 CD - 1 s 75 5 . 0 -- -- -- -- -- -- -- -- -- -- 73 0 . 9 3 73 0 . 9 0 73 2 . 1 5 73 0 . 6 8 73 0 . 5 1 73 0 . 9 2 73 5 . 6 5 73 7 CD - 1 d 75 7 . 4 -- -- -- -- -- 73 4 . 5 1 73 4 . 6 8 73 4 . 5 2 73 4 . 2 6 73 2 . 7 3 73 0 . 6 6 73 0 . 6 8 73 1 . 9 1 73 0 . 4 6 73 0 . 2 8 73 0 . 6 4 73 8 . 1 8 73 9 CD - 2 73 3 . 0 -- -- -- -- -- -- -- -- -- -- 71 8 . 9 9 71 8 . 9 6 71 8 . 8 4 71 8 . 7 7 71 7 . 7 2 71 8 . 1 1 72 3 . 0 0 72 4 CD - 3 75 3 . 3 -- -- -- -- -- -- -- -- -- -- 70 5 . 0 3 70 5 . 0 5 70 6 . 1 3 70 4 . 4 5 70 4 . 6 2 Ab a n d o n e d 70 9 . 6 3 71 1 CD - 3 ( r e l o c a t e d ) 74 4 . 4 8 -- -- -- -- -- -- -- -- -- -- 70 6 . 1 70 9 . 6 0 71 1 CD - 4 75 5 . 5 0 -- -- -- -- -- -- -- -- -- -- 73 0 . 5 5 73 0 . 6 0 73 1 . 3 6 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 73 4 . 8 6 73 6 CD - 4 r e p 73 9 . 1 5 -- -- -- -- -- -- -- -- -- -- 72 9 . 3 4 72 9 . 4 8 72 9 . 2 0 72 9 . 4 5 72 8 . 8 4 72 8 . 7 0 73 2 . 9 8 73 4 CD - 5 75 8 . 7 0 -- -- -- -- -- -- -- -- -- -- 71 7 . 2 8 71 7 . 2 9 71 7 . 3 7 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 72 0 . 8 7 72 2 CD - 6 74 1 . 4 0 -- -- -- -- -- -- -- -- -- -- 70 7 . 8 4 70 7 . 8 6 70 9 . 0 9 70 7 . 2 2 70 7 . 5 1 NM 71 2 . 5 9 71 4 MW - 2 73 3 . 7 8 72 9 . 4 8 -- 72 8 . 3 6 70 6 . 9 4 70 6 . 7 8 70 6 . 5 1 70 6 . 3 3 70 6 . 2 3 70 7 . 1 3 72 7 . 7 5 72 5 . 1 7 72 6 . 0 7 72 2 . 4 3 NM NM Ab a n d o n e d 73 2 . 9 8 73 4 MW - A 74 6 . 8 0 70 6 . 0 0 -- 70 3 . 5 0 70 3 . 6 9 70 3 . 6 3 70 3 . 6 2 70 3 . 5 1 70 3 . 4 0 70 3 . 4 4 70 3 . 2 5 70 1 . 9 4 70 2 . 4 3 70 3 . 8 8 70 4 . 2 6 70 4 . 0 9 69 6 . 2 0 70 9 . 5 0 71 1 MW - J 72 8 . 4 7 69 8 . 9 7 70 3 . 9 2 70 1 . 4 5 70 0 . 4 4 70 0 . 2 3 70 0 . 1 7 70 0 . 1 0 69 9 . 9 6 70 0 . 1 3 70 0 . 3 2 69 8 . 6 7 69 9 . 1 0 69 9 . 6 9 69 9 . 2 6 69 8 . 5 2 NM 70 7 . 4 2 70 8 MW - X 71 0 . 2 8 69 4 . 3 9 69 6 . 7 3 69 8 . 3 8 69 7 . 9 5 69 8 . 3 0 69 7 . 8 8 69 7 . 8 3 69 7 . 8 4 NM 69 8 . 3 8 69 8 . 0 3 69 8 . 3 3 69 8 . 7 1 69 7 . 4 5 NM 70 2 . 2 1 70 3 P- 4 73 6 . 1 1 -- -- -- -- -- 73 0 . 7 9 73 0 . 6 6 73 0 . 5 6 73 0 . 4 3 73 0 . 6 1 72 7 . 7 4 72 7 . 7 9 72 8 . 1 3 NM NM NM 73 4 . 2 9 73 5 P- 6 76 9 . 7 2 -- -- -- DR Y DR Y DR Y DR Y DR Y DR Y DR Y NM NM NM NM NM NM -- -- P- 7 76 8 . 7 9 -- -- -- DR Y DR Y DR Y DR Y DR Y DR Y DR Y NM NM NM NM NM NM -- -- P- 8 74 2 . 0 1 -- -- -- 72 9 . 4 0 72 9 . 2 0 72 9 . 5 6 72 9 . 2 6 72 9 . 1 1 72 8 . 7 5 72 9 . 7 6 DR Y DR Y 73 0 . 6 3 NM NM NM 73 4 . 1 3 73 5 P- 9 75 6 . 9 3 -- -- -- DR Y DR Y DR Y DR Y DR Y DR Y DR Y Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d -- -- M- 2 75 5 . 1 8 -- -- -- -- -- 73 6 . 4 3 73 6 . 2 8 73 6 . 3 1 73 5 . 9 8 73 6 . 3 4 NM NM NM NM NM NM 73 9 . 9 3 74 1 M- 4 75 4 . 0 7 -- -- -- 73 9 . 7 9 73 9 . 5 5 73 9 . 5 3 73 9 . 4 0 73 9 . 1 0 73 4 . 5 3 73 1 . 4 2 Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d Ab a n d o n e d 74 3 . 2 9 74 4 M- 5 76 9 . 9 2 -- -- -- 72 2 . 2 2 72 2 . 1 4 72 1 . 9 9 72 1 . 8 7 72 1 . 7 2 73 7 . 4 2 73 7 . 7 2 NM NM NM NM NM NM 74 1 . 2 2 74 2 No t e s : MS L - M e a n S e a L e v e l NM - N o t M e a s u r e d * - B - 1 3 w a s c o n v e r t e d t o C D - 1 d . -- N o D a t a Ta b l e 3 - 4 C A B A R R U S C O U N T Y N O R T H C A R O L I N A N XREFs: [CE_SURVEY, RC09STPL] Images: []Last saved by: KOSKIAR Time: 1/4/2017 7:54:34 AMpw:\\DACPWAPP2:PW_PL1\1278\114357\04 Design Services NM_30%\02 Civil\10 CADD\FIG-3-2.dwg F I G U R E G R O U N D W A T E R C O N T O U R M A P D E S I G N H Y D R O G E O L O G I C I N V E S T I G A T I O N 3 - 2 P H A S E I I I & I V U N L I N E D C & D L A N D F I L L E X P A N S I O N C A B A R R U S C O U N T Y C & D L A N D F I L L Table 3-5 Historic Water Level Measurements - Site Monitoring Wells Cabarrus County Construction and Demolition Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Facility Permit Monitoring Well Top of Casing Number Code Elevation (AMSL) 13-02 MW-1 701.37 691.74 689.72 689.70 690.19 690.52 690.41 690.67 690.71 690.67 690.67 690.26 13-02 MW-3 670.37 13-02 MW-3 deep 668.33 13-02 MW-9 780.25 743.15 739.48 739.74 738.96 739.39 740.36 739.60 739.94 739.34 741.58 739.21 13-02 MW-A 746.80 709.35 705.83 705.74 705.36 705.52 705.29 704.98 705.20 704.86 705.82 704.94 13-02 MW-B 681.66 674.65 676.32 676.28 676.78 677.16 672.22 677.70 677.86 678.23 678.57 678.03 13-02 MW-C 694.98 686.83 685.02 684.81 685.35 686.02 685.98 685.65 686.77 685.31 687.13 684.05 13-02 MW-D 720.28 704.78 699.41 698.74 697.66 697.78 697.26 696.25 696.08 695.43 696.85 695.23 13-02 MW-E Rep 712.58 684.16 680.91 681.69 682.28 682.93 682.99 689.33 689.42 688.01 689.69 687.15 13-02 MW-E deep 705.70 13-02 MW-F 681.06 672.58 670.94 670.94 671.29 671.78 671.60 671.68 671.77 671.78 672.01 671.23 13-02 MW-G 695.19 687.89 686.34 686.22 686.99 687.68 687.52 687.02 687.04 686.76 687.31 686.11 13-02 MW-H 699.23 13-02 MW-H deep 699.17 13-02 MW-I 709.30 13-02 MW-J 728.47 13-02 MW-K 702.91 13-02 MW-L 669.54 13-02 MW-L deep 672.51 13-02 MW-M 668.49 13-02 MW-X 710.28 13-02 CD-1s (background well)755.00 13-02 CD-1d (background well)757.40 13-02 CD-4 755.50 13-02 CD-5 758.70 13-02 CD-6 741.40 13-02 AMW-1s 725.30 13-02 AMW-1d 725.80 13-02 AMW-2s 694.50 13-02 AMW-2d 694.50 Notes: 1. AMSL = Above Mean Sea Level NS = Not Sampled 2. Blank Cells - Water level not measured or well not installed 3. MW-E deep, -H, -H deep, -I, -J, -K, -L, were installed in June 1999. 4. Asessment wells CD-4, -5, and -6 were installed in September 2006. 5. Assessment wells AMW-1s, -1d, -2s, and -2d were installed in October 2009. 6. CD-4 and CD-5 were abandoned in July 2010. 7. The November 2012 sampling event was the first event that CD-1s/CD-1d replaced MW-9 as the background monitoring wells. 8. MW-9 was removed from the monitoring program in November 2012. 9. MW-E Rep was not sampled during the Novemver 2012 sampling event due to laboratory oversight. 11/13/1995Sampling Event 10/18/1994 2/14/1995 6/9/1995 10/24/1995 11/9/1998 Groundwater Elevation (AMSL) 1/26/1996 12/5/1996 5/2/1997 11/4/1997 4/18/1999 Page 1 of 5 Table 3-5 Table 3-5 Historic Water Level Measurements - Site Monitoring Wells Cabarrus County Construction and Demolition Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Facility Permit Monitoring Well Top of Casing Number Code Elevation (AMSL) 13-02 MW-1 701.37 13-02 MW-3 670.37 13-02 MW-3 deep 668.33 13-02 MW-9 780.25 13-02 MW-A 746.80 13-02 MW-B 681.66 13-02 MW-C 694.98 13-02 MW-D 720.28 13-02 MW-E Rep 712.58 13-02 MW-E deep 705.70 13-02 MW-F 681.06 13-02 MW-G 695.19 13-02 MW-H 699.23 13-02 MW-H deep 699.17 13-02 MW-I 709.30 13-02 MW-J 728.47 13-02 MW-K 702.91 13-02 MW-L 669.54 13-02 MW-L deep 672.51 13-02 MW-M 668.49 13-02 MW-X 710.28 13-02 CD-1s (background well)755.00 13-02 CD-1d (background well)757.40 13-02 CD-4 755.50 13-02 CD-5 758.70 13-02 CD-6 741.40 13-02 AMW-1s 725.30 13-02 AMW-1d 725.80 13-02 AMW-2s 694.50 13-02 AMW-2d 694.50 Notes: 1. AMSL = Above Mean Sea Level NS = Not Sampled 2. Blank Cells - Water level not measured or well not installed 3. MW-E deep, -H, -H deep, -I, -J, -K, -L, were installed in June 1999. 4. Asessment wells CD-4, -5, and -6 were installed in September 2006. 5. Assessment wells AMW-1s, -1d, -2s, and -2d were installed in October 2009. 6. CD-4 and CD-5 were abandoned in July 2010. 7. The November 2012 sampling event was the first event that CD-1s/CD-1d replaced MW-9 as the background monitoring wells. 8. MW-9 was removed from the monitoring program in November 2012. 9. MW-E Rep was not sampled during the Novemver 2012 sampling event due to laboratory oversight. Sampling Event 690.37 690.15 690.05 689.91 689.70 689.75 689.49 689.96 690.06 690.54 689.58 651.74 651.71 654.24 739.15 737.90 738.76 737.53 737.39 737.06 737.09 735.92 739.12 742.56 741.50 704.90 703.02 703.10 702.66 702.07 701.66 701.31 700.87 702.58 704.46 704.00 678.01 678.26 678.32 678.25 678.29 678.41 678.97 678.76 678.76 678.83 678.79 684.03 683.93 685.68 683.24 684.12 683.27 684.29 683.90 686.65 684.11 686.36 695.20 693.39 693.58 692.55 691.85 691.21 DRY DRY 692.98 693.96 694.07 687.13 684.12 684.08 682.97 681.65 NS 680.77 650.58 658.09 659.82 658.32 673.76 673.75 672.69 671.35 672.60 670.44 672.54 673.17 674.99 673.46 671.16 671.74 672.14 671.12 672.13 673.15 672.54 671.86 672.76 672.15 671.96 686.09 686.26 686.27 686.11 686.03 685.96 685.93 686.74 686.47 685.99 686.17 674.03 673.70 672.64 671.11 670.43 669.81 668.81 671.48 675.22 673.85 673.57 673.22 672.39 670.83 670.04 669.38 668.49 671.02 674.56 673.06 663.72 661.87 662.79 659.92 659.75 660.16 658.80 663.75 662.92 662.27 699.29 700.72 699.13 699.03 698.23 699.02 697.63 700.51 701.06 701.21 678.75 680.57 678.19 678.63 677.56 678.74 677.93 681.63 681.52 681.49 654.18 655.46 653.26 651.77 652.72 651.69 650.01 654.43 NS 653.16 654.62 649.33 697.85 700.05 698.98 NS NS NS NS NS 698.66 700.30 5/8/20013/31/1999 11/16/1999 4/24/2000 9/26/2000 Groundwater Elevation (AMSL) 4/23/2002 10/14/2002 4/25/2003 10/23/2003 4/21/200410/30/2001 Page 2 of 5 Table 3-5 Table 3-5 Historic Water Level Measurements - Site Monitoring Wells Cabarrus County Construction and Demolition Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Facility Permit Monitoring Well Top of Casing Number Code Elevation (AMSL) 13-02 MW-1 701.37 13-02 MW-3 670.37 13-02 MW-3 deep 668.33 13-02 MW-9 780.25 13-02 MW-A 746.80 13-02 MW-B 681.66 13-02 MW-C 694.98 13-02 MW-D 720.28 13-02 MW-E Rep 712.58 13-02 MW-E deep 705.70 13-02 MW-F 681.06 13-02 MW-G 695.19 13-02 MW-H 699.23 13-02 MW-H deep 699.17 13-02 MW-I 709.30 13-02 MW-J 728.47 13-02 MW-K 702.91 13-02 MW-L 669.54 13-02 MW-L deep 672.51 13-02 MW-M 668.49 13-02 MW-X 710.28 13-02 CD-1s (background well)755.00 13-02 CD-1d (background well)757.40 13-02 CD-4 755.50 13-02 CD-5 758.70 13-02 CD-6 741.40 13-02 AMW-1s 725.30 13-02 AMW-1d 725.80 13-02 AMW-2s 694.50 13-02 AMW-2d 694.50 Notes: 1. AMSL = Above Mean Sea Level NS = Not Sampled 2. Blank Cells - Water level not measured or well not installed 3. MW-E deep, -H, -H deep, -I, -J, -K, -L, were installed in June 1999. 4. Asessment wells CD-4, -5, and -6 were installed in September 2006. 5. Assessment wells AMW-1s, -1d, -2s, and -2d were installed in October 2009. 6. CD-4 and CD-5 were abandoned in July 2010. 7. The November 2012 sampling event was the first event that CD-1s/CD-1d replaced MW-9 as the background monitoring wells. 8. MW-9 was removed from the monitoring program in November 2012. 9. MW-E Rep was not sampled during the Novemver 2012 sampling event due to laboratory oversight. Sampling Event 689.42 689.61 689.14 688.35 689.18 689.43 688.76 689.38 688.61 689.63 651.24 652.13 650.90 650.28 650.65 652.92 650.19 651.34 650.54 652.17 NS 654.99 NS 654.26 NS 656.27 NS 654.84 NS 655.48 740.20 740.65 739.40 738.81 737.56 739.23 736.51 736.21 735.60 736.89 703.21 704.19 704.19 703.58 702.63 704.32 703.53 702.80 702.51 703.00 679.06 678.87 678.54 678.72 679.41 678.88 678.01 679.11 679.16 678.93 684.81 687.48 684.09 685.29 686.94 688.77 683.34 688.23 684.17 689.26 693.16 695.38 693.51 691.56 693.22 695.68 692.84 693.82 692.19 695.48 656.72 682.73 681.48 680.38 679.52 682.58 680.23 679.99 679.34 680.87 671.87 672.49 671.19 670.01 669.78 672.27 669.96 669.70 669.06 670.66 671.94 672.26 670.01 671.15 672.06 673.43 668.43 672.49 672.75 672.78 685.94 686.17 685.78 685.37 686.03 686.08 685.08 686.07 685.99 686.22 672.15 672.63 671.35 671.19 670.14 672.00 669.89 669.79 668.75 670.25 671.57 671.77 670.89 669.67 669.69 671.44 669.54 668.97 668.36 669.50 661.51 662.62 660.96 660.60 661.60 663.58 660.07 661.73 660.82 662.40 699.97 701.21 699.63 699.63 699.52 701.72 698.05 699.78 698.29 700.48 680.36 682.26 679.58 680.20 678.01 681.85 677.52 680.11 678.53 681.12 NS 653.80 NS 652.69 NS 652.70 NS 652.84 NS 653.43 NS 655.20 NS 654.11 NS 655.72 NS 654.09 NS 654.93 NS 649.79 NS 646.31 NS 650.30 NS 649.08 NS 650.34 698.18 699.92 697.73 697.67 698.25 700.31 697.74 698.58 696.84 699.75 732.30 733.22 731.09 731.30 729.54 731.60 732.05 732.98 730.87 731.02 730.34 731.37 731.53 732.09 730.56 730.80 730.37 731.10 719.21 719.02 718.32 717.58 713.47 717.00 710.88 711.68 707.72 708.30 708.10 708.16 4/23/2007 10/29/200710/20/2004 Groundwater Elevation (AMSL) 4/21/2008 11/19/2008 4/7/20094/25/2005 10/24/2005 4/18/2006 10/31/2006 Page 3 of 5 Table 3-5 Table 3-5 Historic Water Level Measurements - Site Monitoring Wells Cabarrus County Construction and Demolition Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Facility Permit Monitoring Well Top of Casing Number Code Elevation (AMSL) 13-02 MW-1 701.37 13-02 MW-3 670.37 13-02 MW-3 deep 668.33 13-02 MW-9 780.25 13-02 MW-A 746.80 13-02 MW-B 681.66 13-02 MW-C 694.98 13-02 MW-D 720.28 13-02 MW-E Rep 712.58 13-02 MW-E deep 705.70 13-02 MW-F 681.06 13-02 MW-G 695.19 13-02 MW-H 699.23 13-02 MW-H deep 699.17 13-02 MW-I 709.30 13-02 MW-J 728.47 13-02 MW-K 702.91 13-02 MW-L 669.54 13-02 MW-L deep 672.51 13-02 MW-M 668.49 13-02 MW-X 710.28 13-02 CD-1s (background well)755.00 13-02 CD-1d (background well)757.40 13-02 CD-4 755.50 13-02 CD-5 758.70 13-02 CD-6 741.40 13-02 AMW-1s 725.30 13-02 AMW-1d 725.80 13-02 AMW-2s 694.50 13-02 AMW-2d 694.50 Notes: 1. AMSL = Above Mean Sea Level NS = Not Sampled 2. Blank Cells - Water level not measured or well not installed 3. MW-E deep, -H, -H deep, -I, -J, -K, -L, were installed in June 1999. 4. Asessment wells CD-4, -5, and -6 were installed in September 2006. 5. Assessment wells AMW-1s, -1d, -2s, and -2d were installed in October 2009. 6. CD-4 and CD-5 were abandoned in July 2010. 7. The November 2012 sampling event was the first event that CD-1s/CD-1d replaced MW-9 as the background monitoring wells. 8. MW-9 was removed from the monitoring program in November 2012. 9. MW-E Rep was not sampled during the Novemver 2012 sampling event due to laboratory oversight. Sampling Event 688.79 689.23 688.92 689.08 689.35 689.82 688.87 690.81 689.03 689.32 651.06 652.87 651.45 652.20 651.67 654.06 652.48 654.70 654.34 656.75 NS 654.13 NS 655.15 NS 656.74 NS 657.43 NS 659.63 735.72 738.26 736.58 736.07 734.92 735.84 NS NS NS NS 704.08 704.95 704.08 703.02 702.39 703.59 703.09 702.45 703.45 705.01 679.38 678.61 677.64 679.04 679.56 678.34 677.44 679.71 678.96 678.96 690.07 686.35 684.02 686.66 683.43 684.58 682.88 690.12 683.78 688.55 696.37 695.21 693.40 692.88 691.48 693.12 691.60 692.15 692.58 696.21 679.75 682.54 680.82 679.94 679.07 682.38 NS 680.25 682.53 685.83 670.29 671.99 673.60 669.66 668.80 671.10 669.31 670.05 672.21 675.55 668.88 671.96 669.43 672.27 672.60 671.61 667.86 673.91 671.41 672.51 685.21 685.91 685.69 685.79 686.40 685.46 685.72 686.74 685.69 685.78 670.61 671.86 670.67 670.19 669.25 671.30 669.74 670.32 672.62 675.66 670.25 671.40 670.07 669.30 668.54 670.81 669.32 669.72 672.17 675.17 660.39 663.19 661.05 661.43 660.65 662.40 660.82 662.70 662.90 665.83 701.65 699.97 698.20 698.68 697.11 698.49 696.45 698.77 698.02 700.14 678.81 681.50 678.62 679.22 676.91 679.73 676.51 679.51 679.51 682.24 NS 653.86 652.74 653.13 651.96 654.24 652.71 655.24 655.24 657.83 NS 655.61 NS 654.62 NS 655.81 NS 656.74 656.74 659.35 NS 649.00 NS 647.85 NS 648.19 NS 649.98 649.98 650.69 700.27 698.54 696.93 697.62 700.80 697.38 695.25 699.28 699.28 698.95 730.59 731.50 730.72 730.81 729.60 730.65 728.94 729.28 729.28 731.82 730.39 732.22 730.53 730.49 729.46 730.96 728.75 729.09 729.09 731.54 730.28 731.52 ---------------- 717.43 715.22 ---------------- 708.65 710.60 709.15 707.71 706.81 707.55 706.10 706.02 706.02 710.20 671.18 673.32 671.80 670.87 670.00 672.32 670.00 671.30 671.30 676.79 668.09 673.10 671.60 670.58 669.77 672.03 670.34 671.05 671.05 676.62 668.20 670.09 668.74 668.16 667.10 669.38 667.78 671.47 671.47 673.40 668.87 670.67 669.24 668.49 667.68 669.90 668.32 669.12 669.12 673.95 10/14/2009 5/6/2010 11/1/2010 5/6/2013 11/4/2013 5/5/20145/3/2011 11/7/2011 5/7/2012 11/26/2012 Groundwater Elevation (AMSL) Page 4 of 5 Table 3-5 Table 3-5 Historic Water Level Measurements - Site Monitoring Wells Cabarrus County Construction and Demolition Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Facility Permit Monitoring Well Top of Casing Number Code Elevation (AMSL) 13-02 MW-1 701.37 13-02 MW-3 670.37 13-02 MW-3 deep 668.33 13-02 MW-9 780.25 13-02 MW-A 746.80 13-02 MW-B 681.66 13-02 MW-C 694.98 13-02 MW-D 720.28 13-02 MW-E Rep 712.58 13-02 MW-E deep 705.70 13-02 MW-F 681.06 13-02 MW-G 695.19 13-02 MW-H 699.23 13-02 MW-H deep 699.17 13-02 MW-I 709.30 13-02 MW-J 728.47 13-02 MW-K 702.91 13-02 MW-L 669.54 13-02 MW-L deep 672.51 13-02 MW-M 668.49 13-02 MW-X 710.28 13-02 CD-1s (background well)755.00 13-02 CD-1d (background well)757.40 13-02 CD-4 755.50 13-02 CD-5 758.70 13-02 CD-6 741.40 13-02 AMW-1s 725.30 13-02 AMW-1d 725.80 13-02 AMW-2s 694.50 13-02 AMW-2d 694.50 Notes: 1. AMSL = Above Mean Sea Level NS = Not Sampled 2. Blank Cells - Water level not measured or well not installed 3. MW-E deep, -H, -H deep, -I, -J, -K, -L, were installed in June 1999. 4. Asessment wells CD-4, -5, and -6 were installed in September 2006. 5. Assessment wells AMW-1s, -1d, -2s, and -2d were installed in October 2009. 6. CD-4 and CD-5 were abandoned in July 2010. 7. The November 2012 sampling event was the first event that CD-1s/CD-1d replaced MW-9 as the background monitoring wells. 8. MW-9 was removed from the monitoring program in November 2012. 9. MW-E Rep was not sampled during the Novemver 2012 sampling event due to laboratory oversight. Sampling Event 690.73 689.22 688.97 688.94 688.76 652.60 655.97 654.26 657.31 655.78 NS 658.99 657.48 660.27 659.10 NS NS NS NS NS 702.49 703.28 702.60 704.73 704.39 675.25 679.06 678.86 678.89 678.77 682.14 688.33 682.70 688.74 683.29 692.98 692.78 691.53 694.50 693.39 682.49 683.00 680.93 684.97 683.18 672.75 672.71 670.65 674.67 672.88 668.38 672.66 671.66 672.46 670.61 685.11 685.68 685.68 685.62 685.65 672.74 672.67 671.03 674.90 673.29 672.33 672.32 670.62 674.52 672.96 662.00 664.00 662.17 665.50 663.72 696.55 699.10 696.77 699.52 698.05 677.86 680.25 676.84 681.21 678.35 654.03 656.54 654.39 657.90 655.72 NS 658.15 656.14 659.50 657.51 NS 649.52 648.01 649.94 648.79 695.53 698.02 696.14 698.64 696.83 730.20 730.42 728.55 731.10 727.17 729.95 730.20 728.33 730.89 732.17 ---------- ---------- 709.30 707.64 706.65 708.75 708.44 674.05 674.06 672.00 676.07 674.31 673.02 673.85 671.73 675.85 674.09 670.29 671.07 669.09 672.97 671.18 670.70 671.60 669.65 673.53 671.82 10/31/2016 Groundwater Elevation (AMSL) 10/26/201511/3/2014 5/4/2015 5/16/2016 Page 5 of 5 Table 3-5 Section 3 • Current Investigation Results 3-18 (revised January 2017) Vertical gradient data is evaluated by comparing water levels from nested piezometer pairs. Nested piezometer pairs are present at the existing C&D landfill (CD-1s/1d), in the proposed Phase 3 and 4 expansion areas (B-18s/18d and B-1s/1d). Vertical gradients are calculated as the difference in water level elevation between two nested piezometers, divided by the vertical distance from the saturated midpoint of the sand filter pack of the shallower well to the saturated midpoint of the sand filter pack in the deeper well. The August 4, 2016 water level elevations indicated the presence of a very slight gradient (indicated by a negative gradient value) at well nests B-1s/B-1d and CD-1s/CD-1d and a very slight upward gradient at nests B-18s/B-18d. The downward gradients indicate areas that serve as recharge areas and groundwater is moving from the PWR to the bedrock. The upward gradients indicate that groundwater is discharging from the bedrock to the PWR, however, there were no seeps or springs visible near the well nests. Well Nest Shallow GW Elevation (MSL) Deep GW Elevation (MSL) GW Elevation Difference (ft) Shallow Screen Saturated Midpoint (MSL) Deep Screen Saturated Midpoint (MSL) Screen Midpoint Separation (ft) Calculated Vertical Gradient (ft/ft) CD-1s/1d 730.92 730.64 -0.28 727.46 710.00 17.46 -0.016 B- 18s/18d 706.38 706.43 +0.05 705.24 695.40 9.84 +0.005 B-1s/1d 706.72 706.69 -0.03 704.98 691.25 13.73 -0.002 GW – Groundwater MSL – Mean Sea Level 3.3.1.2 Temporal Trends Since 1994, the average annual precipitation in Concord, North Carolina is approximately 45 inches. From January 1994 to November 2016, the average monthly precipitation ranged from a low of 3.05 inches in November to a high of 5.38 inches in July. Long-term monthly precipitation summary statistics are provided in Table 3-6 and Figure 3-3. The precipitation data indicated that peak rainfall for this area would be expected to occur in the summer between June and September. Precipitation during the summer months generally falls in large amounts over short periods of time, which results in increased runoff; thus decreasing the amount of precipitation available for infiltration. Therefore, lower groundwater levels would also be expected to occur during this time due to less precipitation infiltration and the increased loss of water by evapotranspiration. Above average amounts of rainfall also occur during March and April. Since precipitation in the late winter/early spring months generally occurs as a slow, steady rainfall, and evapotranspiration is minimal, more precipitation is available for infiltration. Therefore, groundwater levels would change more rapidly in response to a precipitation event. It would be expected that the seasonal high water table would occur in late winter to early spring (January to March) in response to precipitation during this period. Historical groundwater data from the monitoring wells at the closed Units 1, 2, and 3 landfills indicate that the highest groundwater levels typically occur in April or May. Ta b l e 3 - 6 An n u a l P r e c i p i t a t i o n D a t a - C o n c o r d S t a t i o n Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n Ye a r JA N FE B MA R AP R MA Y JU N JU L AU G SE P OC T NO V DE C AN N U A L 19 9 4 4. 9 4 2. 7 7 6. 2 3 3. 9 6 1. 7 9 9. 7 2 6. 6 5 4. 9 7 2. 4 4 3. 6 7 2. 9 2 1. 5 3 51 . 5 9 19 9 5 4. 4 2 5. 9 4 2. 7 5 0. 8 3 3. 9 9 7. 0 8 3. 7 6 10 . 5 3. 8 5. 9 6 6. 1 2 1. 2 7 56 . 4 2 19 9 6 4. 8 3 2. 4 3 3. 4 5 3. 9 4 2. 4 3 3. 7 7 5. 7 1 4. 4 2 5. 2 9 3. 1 9 2. 8 8 2. 7 7 45 . 1 1 19 9 7 3. 5 4 3. 5 7 4. 3 4 7. 2 4 1. 4 5 3. 3 1 11 . 8 3 1. 0 2 6. 2 6 4. 9 1 4. 1 9 4. 1 55 . 7 6 19 9 8 7. 1 1 4. 0 8 3. 3 5. 4 4 2. 2 5 2. 6 2 2. 5 8 1. 3 4 5. 3 1 1. 2 5 2. 3 7 3. 9 8 41 . 6 3 19 9 9 4. 9 6 2. 1 7 1. 4 2 5. 2 1 1. 0 7 3. 5 2 2. 7 1. 8 7 6. 0 3 5. 8 1 1. 7 5 1. 7 7 38 . 2 8 20 0 0 4. 1 2 2. 5 4. 2 9 5. 4 8 3. 3 5 0. 9 5 3. 8 2 3. 2 7 9. 5 4 0 2. 8 8 0. 9 6 41 . 1 6 20 0 1 1. 7 9 2. 2 3 5. 5 3 1. 0 9 3. 2 4 7. 0 5 4. 5 3 5. 8 8 3. 2 4 0. 3 8 0. 6 3 2. 1 6 37 . 7 5 20 0 2 4. 7 7 1. 3 3 4. 2 9 1. 1 9 1. 9 4 0. 7 9 3. 8 2. 4 2 4. 9 2 8. 2 2 4. 2 7 5. 0 0 42 . 9 4 20 0 3 1. 5 9 3. 6 9 8. 2 8 9. 8 9 9. 9 7 7. 8 3 8. 0 8 4. 0 1 1. 6 7 2. 0 1 1. 2 2. 6 6 60 . 8 8 20 0 4 1. 2 9 3. 9 9 0. 8 1 1. 7 5 3. 1 8 6. 1 6 7. 3 4 4. 3 9 11 . 2 3 1. 8 1 3. 7 8 0. 7 1 46 . 4 4 20 0 5 1. 5 4 2. 8 7 4. 6 2. 8 8 1. 6 6 4. 7 8 6. 4 6 3. 7 7 0. 1 8 4. 7 3. 1 2 4. 9 9 41 . 5 5 20 0 6 2. 2 1 1. 1 2 1. 9 1 3. 4 4 1. 1 6 7. 0 3 3. 0 3 6. 8 4 3. 7 9 4. 2 1 6. 4 2. 4 6 43 . 6 20 0 7 3. 2 9 3. 0 5 3. 4 4 3. 9 1 2. 1 9 2. 6 3 3. 8 8 0. 3 9 0. 3 8 4. 6 5 0. 8 1 3. 6 9 32 . 3 1 20 0 8 1. 4 1 2. 8 6 3. 9 4. 6 3 3. 6 3. 4 9 6. 4 3 11 . 3 5 5. 2 4 1. 7 6 1. 5 5 4. 7 0 50 . 9 2 20 0 9 2. 6 7 2. 0 9 6. 2 8 3. 0 7 4. 2 4 3. 8 8 12 . 9 1 2. 1 3 1. 7 2. 2 6 6. 0 8 5. 8 5 53 . 1 6 20 1 0 6. 3 1 3. 6 8 3. 7 2 1. 4 4 3. 8 7 4. 0 2 5. 5 4 5. 3 4 2. 4 7 1. 0 8 0. 8 6 2. 0 5 40 . 3 8 20 1 1 1. 5 4 2. 2 8 4. 5 3 2. 3 6 4. 2 2 2. 9 8 2. 3 7 1. 8 5 6. 2 4. 3 3 4. 4 3 3. 4 1 40 . 5 20 1 2 2. 5 8 1. 9 6 2. 6 1. 8 3 6. 4 3 3. 2 7 2. 3 9 5. 6 3. 7 3 1. 1 8 0. 5 3 2. 8 1 34 . 9 1 20 1 3 4. 5 4 3. 5 9 3. 3 3. 7 6 3. 3 7 14 . 2 5. 8 1 4. 9 6 2. 5 5 0. 7 3 3. 0 9 1. 1 1 51 . 0 1 20 1 4 2. 7 9 1. 5 4. 0 3 5. 4 6 3. 8 9 1. 7 3 4. 5 1 3. 4 3 4. 2 8 0. 9 3 2. 8 7 2. 9 3 38 . 3 5 20 1 5 2. 7 8 2. 7 2. 3 9 4. 1 7 1. 2 1 3. 0 7 4. 1 5 3. 9 8 3. 0 0 8. 0 2 6. 9 6. 3 8 48 . 7 5 20 1 6 2. 2 1 3 . 3 6 1 . 3 5 1 . 8 1 7 . 1 6 4 . 0 0 5 . 5 4 3 . 0 6 4 . 3 6 3 . 1 0 0 . 4 2 36 . 3 7 Av e r a g e 3. 3 6 2. 8 6 3. 7 7 3. 6 9 3. 3 8 4. 6 9 5. 3 8 4. 2 1 4. 2 4 3. 2 2 3. 0 5 3. 0 6 44 . 9 1 No t e s : So u r c e - C l i m a t o l o g i c a l D a t a - A n n u a l S u m m a r y N o r t h C a r o l i n a MO N T H L Y P R E C I P I T A T I O N ( i n c h e s ) Ta b l e 3 - 6 . x l s x Fi g u r e 3 - 3 Av e r a g e M o n t h l y P r e c i p i t a t i o n Co n c o r d S t a t i o n Co n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n Fi g u r e 3 - 3 0. 0 0 1. 0 0 2. 0 0 3. 0 0 4. 0 0 5. 0 0 6. 0 0 JA N F E B M A R A P R M A Y J U N J U L A U G S E P O C T N O V D E C P r e c i p i t a t i o n ( i n c h e s ) Mo n t h Section 3 • Current Investigation Results 3-21 (revised January 2017) An evaluation of the historic water level measurements from the monitoring wells across the entire Cabarrus County landfill property indicate that in most cases, groundwater levels have been decreasing since 1994. However, water levels in monitoring wells near the drainage features tend to stay relatively stable. In order to maintain the required 4 foot separation between the landfill bottom and the seasonal high groundwater surface, a conservative value of 3.5 feet was added to the highest recorded elevation for each piezometer within and adjacent to the proposed Phase 3 and 4 expansion areas. The 3.5 foot value was attained by comparing the highest and lowest recorded elevation in the long-term monitoring well data (Table 3-5), dividing the average difference for all the monitoring wells by two, adding that value to the highest recorded value in the new C&D expansion areas and adding an additional foot. The conservative value of 3.5 ft added to the highest recorded elevation was used to develop the estimated seasonal high groundwater contour map. The seasonal high and long-term seasonal high values used for the previous landfill expansions have remained stable. In some instances, readings collected from some of the older existing wells and probes were erratic and most likely attributed to incorrect well call-out or operator error. Generally, these erroneous values were disregarded in the seasonal high estimations. The estimated seasonal high values for the existing monitoring wells and piezometers are included on Table 3-4. A seasonal high groundwater contour map is provided on Figure 3-2 and a long-term seasonal high groundwater contour map is provided on Figure 3-3. Long-term seasonal high values were estimated by adding 1 foot to the seasonal high values. In some cases, long-term estimated seasonal high elevations were higher than land surface and land surface was utilized as the maximum elevation. 3.3.2 Slug Test Results Slug tests were performed on select piezometers within and adjacent to the existing C&D Landfill expansion area. In addition, data from slug tests conducted during previous investigations adjacent to the current C&D Landfill were also reviewed. Given the lithologically similar conditions found at the proposed expansion areas and the active C&D Landfill, this data would likely be representative of the hydraulic conductivity expected at the proposed C&D Landfill expansion area. Slug tests were performed on piezometers B-17s, -17d, and CD-4 Rep, as well as the monitoring wells around the existing C&D Landfill. Using slug-out (recovery) data, hydraulic conductivity (K) values ranged from 0.10 feet per day (ft/day) at CD-4 Rep to 0.37 ft/day at B-17d. In addition, slug tests were also performed on abandoned monitoring wells CD-4 and CD-5, which were within the existing C&D landfill area. Using recovery data, K values were 0.27 ft/day at CD-4, and 0.16 ft/day at CD-5. The average K for all piezometers in areas adjacent to the proposed expansion areas was 0.23 ft/day. These values are similar to those seen adjacent to the active C&D Landfill. A summary of calculated K values is provided on Table 3-7. Calculations and graphs for the K values from B- 17s, B-17d, and CD-4 rep are provided in Appendix D. C A B A R R U S C O U N T Y N O R T H C A R O L I N A N XREFs: [CE_SURVEY, RC09STPL] Images: []Last saved by: KOSKIAR Time: 1/4/2017 7:54:27 AMpw:\\DACPWAPP2:PW_PL1\1278\114357\04 Design Services NM_30%\02 Civil\10 CADD\FIG-3-4.dwg F I G U R E E S T I M A T E D S E A S O N A L H I G H G R O U N D W A T E R C O N T O U R M A P D E S I G N H Y D R O G E O L O G I C I N V E S T I G A T I O N 3 - 4 P H A S E I I I & I V U N L I N E D C & D L A N D F I L L E X P A N S I O N C A B A R R U S C O U N T Y C & D L A N D F I L L C A B A R R U S C O U N T Y N O R T H C A R O L I N A N XREFs: [CE_SURVEY, RC01STPL] Images: []Last saved by: KOSKIAR Time: 9/6/2016 11:06:53 AMpw:\\DACPWAPP2:PW_PL1\1278\114357\04 Design Services NM_30%\02 Civil\10 CADD\FIG-6N.dwg F I G U R E L O N G - T E R M S E A S O N A L H I G H G R O U N D W A T E R C O N T O U R M A P D E S I G N H Y D R O G E O L O G I C I N V E S T I G A T I O N 3 - 5 P H A S E I I I & I V U N L I N E D C & D L A N D F I L L E X P A N S I O N C A B A R R U S C O U N T Y C & D L A N D F I L L Ta b l e 3 - 7 Hy d r a u l i c C o n d u c t i v i t y S u m m a r y Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n Bo r i n g D e p t h A q u i f e r M o n i t o r e d K K K K We l l I D (f t ) In t e r v a l (i n / s e c ) ( f t / m i n ) ( f t / d a y ) ( c m / s e c ) B- 1 7 s S l u g I n 38 Sa p r o l i t e / P W R 3 . 7 8 E - 0 5 1 . 8 9 E - 0 4 0 . 2 7 9 . 6 0 E - 0 5 B- 1 7 s S l u g O u t 38 Sa p r o l i t e / P W R 4 . 3 6 E - 0 5 2 . 1 8 E - 0 4 0 . 3 1 1 . 1 1 E - 0 4 B- 1 7 d S l u g I n 47 Be d r o c k 4 . 4 4 E - 0 5 2 . 2 2 E - 0 4 0 . 3 2 1 . 1 3 E - 0 4 B- 1 7 d S l u g O u t 47 Be d r o c k 5 . 0 8 E - 0 5 2 . 5 4 E - 0 4 0 . 3 7 1 . 2 9 E - 0 4 CD - 4 R e p S l u g I n 16 Sa r o l i t e 1 . 5 6 E - 0 5 7 . 8 2 E - 0 5 0 . 1 1 3 . 9 7 E - 0 5 CD - 4 R e p S l u g O u t 16 Sa p r o l i t e 1 . 3 4 E - 0 5 6 . 7 1 E - 0 5 0 . 1 0 3 . 4 1 E - 0 5 CD - 1 s S l u g I n 28 Sa r o l i t e 4 . 7 0 E - 0 6 2 . 3 5 E - 0 5 0 . 0 3 1 . 1 9 E - 0 5 CD - 1 s S l u g O u t 28 Sa p r o l i t e 3 . 4 0 E - 0 6 1 . 7 0 E - 0 5 0 . 0 2 8 . 6 4 E - 0 6 CD - 2 S l u g I n 24 Sa p r o l i t e 3 . 5 0 E - 0 6 1 . 7 5 E - 0 5 0 . 0 3 8 . 8 9 E - 0 6 CD - 2 S l u g O u t 24 Sa p r o l i t e 6 . 1 0 E - 0 6 3 . 0 5 E - 0 5 0 . 0 4 1 . 5 5 E - 0 5 CD - 3 S l u g I n 60 Sa p r o l i t e / P W R 3 . 7 0 E - 0 4 1 . 8 5 E - 0 3 2 . 6 6 9 . 4 0 E - 0 4 CD - 3 S l u g O u t 60 Sa p r o l i t e / P W R 1 . 2 0 E - 0 4 6 . 0 0 E - 0 4 0 . 8 6 3 . 0 5 E - 0 4 CD - 4 S l u g I n 27 Sa p r o l i t e / P W R 3 . 3 0 E - 0 5 1 . 6 5 E - 0 4 0 . 2 4 8 . 3 8 E - 0 5 CD - 4 S l u g O u t 27 Sa p r o l i t e / P W R 3 . 8 0 E - 0 5 1 . 9 0 E - 0 4 0 . 2 7 9 . 6 5 E - 0 5 CD - 5 S l u g I n 60 Sa p r o l i t e / P W R 2 . 3 0 E - 0 5 1 . 1 5 E - 0 4 0 . 1 7 5 . 8 4 E - 0 5 CD - 5 S l u g O u t 60 Sa p r o l i t e / P W R 2 . 2 0 E - 0 5 1 . 1 0 E - 0 4 0 . 1 6 5 . 5 9 E - 0 5 Av e r a g e E x i s t i n g C & D A r e a W e l l s 6 . 2 4 E - 0 5 3 . 1 2 E - 0 4 0 . 6 1 1 . 5 8 E - 0 4 Av e r a g e A l l W e l l s / P i e z o m e t e r s 5 . 1 8 E - 0 5 2 . 5 9 E - 0 4 0 . 3 7 1 . 3 2 E - 0 4 Ta b l e 3 - 7 Section 3 • Current Investigation Results 3-25 (revised January 2017) Slug tests were also performed on the permanent monitoring wells adjacent to the existing C&D Landfill during previous investigations. Hydraulic conductivity values were 0.02ft/d at CD-1s, 0.04 ft/day at CD-2, and 0.86 ft/day at CD-3. Wells CD-1s and CD-2 are screened within saprolite and CD-3 is screened across the saprolite/PWR interface. The average K for all monitoring wells at the active C&D Landfill was 0.61 ft/day. The average K for all piezometers and wells adjacent to the active C&D Landfill and within the proposed expansion areas was 0.37 ft/day. 3.4 Hydrogeologic Conceptual Model Cross-sections identifying hydrogeologic and stratigraphic units, stabilized water table elevations, and groundwater flow-nets are provided in Figure 3-5 and Figure 3-6. 3.4.1 Precipitation and Groundwater Recharge Factors affecting infiltration of precipitation include the rate of precipitation, slope, soil texture, and vegetative cover. Much of the site is covered with fine grained soils with some clay that inhibits infiltration. Areas of lower relief such as flat hilltops and drainage bottoms are expected to be the locations of greatest recharge. Areas covered by forest litter are also expected to enhance infiltration. These factors will affect the amount of infiltration to the greatest extent during periods of extended precipitation. The average monthly precipitation at the site varies over the year. However, precipitation during the summer months typically occurs as sporadic high intensity events of short duration, which leads to runoff. In addition, plant evapotranspiration in the summer leads to higher removal of soil moisture and decreases the potential for deep infiltration. Winter precipitation occurs as events of longer duration and lesser intensity; therefore infiltration and groundwater recharge should be greater in the winter months than in the summer months. This results in a higher groundwater table in the spring. Precipitation that infiltrates into the ground will seep downward as wetting fronts following precipitation. These wetting fronts will follow the path of least resistance through zones of relatively higher conductivity in the saprolite and PWR. Upon reaching a less permeable surface such as the top of hard, unfractured bedrock, the water will spread laterally until it finds another relatively higher conductivity pathway downward such as a weathered zone or a fracture, or until it is discharged to the surface water system. These discharges are generally intermittent, and occur in the secondary drainage features following precipitation events. As saturation is observed within zones of the saprolite materials, PWR, and bedrock, the fractured bedrock material at depth is apparently capable of transmitting water a rate equal to infiltration. The Phase 3 and 4 expansion areas are bounded by the existing C&D landfill to the north and the closed Unit 2 MSW to the east. Groundwater recharge in this area is expected to be less than that compared to other areas of the site. Section 3 • Current Investigation Results 3-28 (revised January 2017) 3.4.2 Groundwater Flow Across the site and within the expansion area, the saturated zone lies primarily within the PWR. At several topographic low areas the saturated zone occurs within the saprolite and PWR. The saturation found in these areas near the bottom of secondary drainage features likely represents water that has infiltrated in surrounding areas and moved laterally, possibly on the bedrock surface, until it accumulated in the lower elevation area. Within the regolith materials, the zone of highest conductance appears to lie immediately above the bedrock surface, due to the presence of lesser amounts of clay minerals in this interval than at the ground surface. Fractures within bedrock also create increased hydraulic conductivity zones. Throughout the expansion area, the PWR and portions of the saprolite are saturated, and represent the primary water-bearing unit of concern for the site. At other areas on the Cabarrus County property, the PWR and shallow fractured bedrock system are the primary water-bearing units. On a larger scale, shallow lateral flow within the fractured bedrock unit will be consistent with the potentiometric surface. However, local hydrogeologic conditions may cause groundwater to flow in different directions than large scale flow. Bedrock fracture flow is very complex and is dependent upon fracture size, orientation, degree of infilling, and connection with other fractures. Localized weathered zones will also affect bedrock fracture flow. Because bedrock fracture flow systems cannot be characterized by direct observation, indirect methods must be used. Data concerning the fracture flow system at the site was obtained through drilling observations, rock core samples, and water level measurements. 3.4.2.1 Groundwater Velocity The groundwater contour map shows that the potentiometric surface, similar to the bedrock surface, is a subdued reflection of surface topography. Topographic divides are generally also groundwater divides and groundwater flow converges into the primary and secondary drainage feature west of the proposed C&D expansion areas. Groundwater flows radially away from topographically high areas. On steeper slopes, the hydraulic gradient steepens. The horizontal gradient from the background wells (CD-1s and 1d) towards the wells in and adjacent to the proposed Phase 3 and 4 expansion areas was approximately 0.023 ft/ft. Using average hydraulic conductivity values from slug testing of wells and piezometers in the C&D area and horizontal hydraulic gradient information, groundwater velocity values were estimated. The average linear velocity of groundwater flow was calculated using the following formula: Vx = Kdh nedl Section 3 • Current Investigation Results 3-29 (revised January 2017) Where, Vx = average linear velocity K = hydraulic conductivity dh/dl = hydraulic gradient ne = effective porosity The average linear flow velocity is provided in Table 3-8. Average groundwater flow velocity in the surficial aquifer at the proposed Phase 3 and 4 C&D Landfill expansion area was approximately 0.3 ft/day. Average groundwater flow velocity in the bedrock aquifer at the existing Phase 2 C&D Landfill expansion was approximately 0.08 ft/day, based on results from B- 18d. The average hydraulic conductivity values were estimated from the slug test data presented in Table 3.7. The hydraulic gradient values were estimated using the potentiometric contour map (Figure 3-2) from August 2016 data. The effective porosity values were estimated based on average values for PWR and the discussion of fractured bedrock in Section 3.2. Using the velocity calculation as described above, the estimated time to travel 250 feet from the edge of waste to the compliance boundary would be about 850 days. This value suggests that a release of a conservative (nonretarded) contaminant from the landfill would likely take 2.5 years to reach the compliance boundary, after the release had reached groundwater. It should be noted that the estimated velocity rates are for average aquifer conditions and that actual velocity rates within bedrock fractures may vary significantly. 3.4.3 Surface Water Interactions and Groundwater Discharge No groundwater discharge features (seeps or springs) were identified in or near the proposed Phase 3 or 4 expansion areas. There is a drainage feature that flows to the south and discharges surface water runoff and discharged groundwater to a pond at the south side of the landfill property. There is a spring-fed pond to the north and west of the existing C&D landfill. Based on topography and groundwater flow, the pond is upgradient of the existing C&D landfill and the proposed expansion areas. 3.5 Groundwater Conditions The following sections discuss the current groundwater quality conditions at the Phase 3 expansion area and planned groundwater assessment monitoring and remedial actions. 3.5.1 Groundwater Quality Based on groundwater sampling results from monitoring wells and piezometers in and around the Phase 3 Expansion area, groundwater contamination from the closed Unit 2 portion of the MSW Landfill is present. An Alternate Source Demonstration (ASD) was submitted to the SWS in September 2013. The ASD summarized that based on the water quality information collected during previous investigations in the C&D landfill area, it is apparent that all contamination located in the area adjacent to the existing C&D landfill is due to impact of leachate from the closed unlined Unit 2 & 3 MSW landfill. Groundwater monitoring wells immediately Ta b l e 3 - 8 Su m m a r y o f C a l c u l a t e d G r o u n d w a t e r F l o w V e l o c i t i e s Ca b a r r u s C o u n t y C o n s t r u c t i o n a n d D e m o l i t i o n L a n d f i l l - P h a s e 3 a n d 4 E x p a n s i o n De s i g n H y d r o g e o l o g i c I n v e s t i g a t i o n Ho r i z o n t a l Es t i m a t e d Pi e z o m e t e r D e s i g n a t i o n Gr a d i e n t (1 ) Ef f e c t i v e (f t / f t ) Po r o s i t y (2 ) Ma x i m u m M i n i m u m A v e r a g e M a x i m u m M i n i m u m A v e r a g e CD - 7 0. 0 2 6 0. 1 1 2. 6 6 0. 2 7 1. 4 7 0. 6 3 0. 0 6 0. 3 5 B- 1 8 s 0. 0 2 3 0. 1 1 2. 6 6 0. 2 7 1. 4 7 0. 5 6 0. 0 6 0. 3 1 B- 1 8 d ( 3 ) 0. 0 2 3 0 . 1 0 0 . 3 7 0 . 3 2 0 . 3 5 0 . 0 9 0 . 0 7 0 . 0 8 CD - 8 0. 0 2 3 0. 1 1 2. 6 6 0. 2 7 1. 4 7 0. 5 6 0. 0 6 0. 3 1 CD - 3 0. 0 2 8 0. 1 1 2. 6 6 0. 2 7 1. 4 7 0. 6 8 0. 0 7 0. 3 7 No t e s : (1 ) H o r i z o n t a l G r a d i e n t c a l c u l a t e d f r o m A u g u s t 2 0 1 6 p o t e n t i o m e t r i c c o n t o u r s a n d d i s t a n c e s o n F i g u r e 3 - 2 . (2 ) - f r o m J o h n s o n S o i l T r i a n g l e ( T a b l e 3 - 3 ) . W e l l s a r e a l l s c r e e n e d i n t h e P W R . A n a v e r a g e v a l u e o f 1 1 % w a s u s e d b a s e d o n T a b l e 3 - 3 . (3 ) - A c o n s e r v a t i v e e f f e c t i v e p o r o s i t y v a l u e o f 1 0 % w a s u s e d b a s e d o n f r a c t u r e d c r y s t a l l i n e r o c k e s t i m a t e s b y D r i s c o l l (4 ) -E s t i m a t e d f r o m c a l c u l a t e d K v a l u e s p r o v i d e d o n T a b l e 3 - 7 . K v a l u e s r e p r e s e n t a v e r a g e s f o r w e l l s a c r o s s t h e C & D s i t e s c r e e n e d i n s i m i l a r l i t h o l o g y . Hy d r a u l i c C o n d u c t i v i t y (4 ) ( f t / d a y ) Av e r a g e L i n e a r V e l o c i t y ( f t / d a y ) Ta b l e 3 - 8 Section 3 • Current Investigation Results 3-31 (revised January 2017) downgradient of the existing C&D landfill (CD-2 and CD-8) have not had detections of any contaminant of concern VOCs. However, CD-3 and CD-7 have had low-level detections of VOC. As discussed in the ASD, the following VOCs are the contaminants of concern for the facility: benzene, 1,4-dichlorobenzene, 1,1-dichloroethane, 1,2-dichloroethane, 1,2-dichloropropane, cis- 1,2-dichloroethene, methylene chloride, tetrachloroethene (PCE), trichloroethene (TCE), and vinyl chloride. The ASD was approved by the SWS in the letter October 14, 2013. A summary of water quality data for wells and piezometers in the C&D area is provided on Table 3-9. Analytical data from the August 2016 sampling event is provided in Appendix E. 3.5.2 Groundwater Assessment and Remediation In December 2008, the Cabarrus County Sanitary Landfill Units 2 and 3 Assessment of Corrective Measures report was submitted to the SWS in accordance with Rule .1635. This report identified potential corrective measures to meet the requirements of Rule .1636. As part of the Assessment of Corrective Measures, several remedies to groundwater contamination and migration were discussed. These remedies included: no action, monitored natural attenuation (MNA), groundwater pump and treat, and in situ groundwater treatment. It was recommended that Cabarrus County pursue MNA and Institutional Controls paired with in situ remediation by enhanced anaerobic bioremediation (EAB) as the preferred remedy. A public meeting was held on March 23, 2009 as directed by Rule .1635(d) to review the results of the corrective measures assessment and receive public comment prior to the selection of remedy. No public comments were received during this process. Following the public meeting, a Selection of Remedy letter was sent to the SWS on March 31, 2009 recommending MNA coupled with Institutional Controls paired with in situ remediation by EAB as the preferred remedial selection due to the ease of implementation, reliability, safety, exposure control, and ability to protect human health and the environment and attain applicable groundwater protection standards. As a contingency plan, the recommended alternatives were in situ chemical remediation or groundwater extraction (CDM, 2009). In the area of the proposed C&D landfill expansion where the ASD was provided, MNA is currently utilized as the corrective action. The in situ remediation by EAB is utilized at the southern portion of the Cabarrus County Landfill facility, south of the closed Unit 3 MSW landfill. A North Carolina Solid Waste Groundwater Corrective Action Permit Modification Application with accompanying documentation was forwarded to the SWS in June 2009. A Corrective Action Plan (CAP) was also submitted to the SWS in June 2009. Review comments for the CAP were received in July 2009 and a revised CAP was submitted to the SWS in August 2009 and approved on September 3, 2009. An Injection Permit was received on October 2, 2009. Injection wells and associated monitoring wells were installed in late October 2009. Injection of EOS ® was completed between November 2 and November 5, 2009. An evaluation of the injection results indicated that as expected, the degradation of PCE, TCE, and dichloroethene happened fairly quickly and the concentrations of vinyl chloride have decreased. Although the injection reduced the concentration of PCE and TCE in bedrock below NC 2L Standards, other compounds continue to be detected above the standards. In accordance with the contingency plan presented in the CAP, an additional assessment will be performed to Section 3 • Current Investigation Results 3-32 (revised January 2017) evaluate the abundance and diversity of the dechlorinating microbial population in the injection area. Based on the biological assessment in the injection area, an additional injection will be performed that may include bioaugmentation. Routine groundwater and MNA sampling is ongoing. Table 3-9 Groundwater Quality Data Summary Cabarrus County C&D Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Fa c i l i t y P e r m i t N u m b e r Mo n i t o r i n g W e l l C o d e Sa m p l e D a t e Ac e t o n e Be n z e n e 2- B u t a n o n e Ch l o r o b e n z e n e Ch l o r o e t h a n e Ch l o r o f o r m 1,2 - D i c h l o r o b e n z e n e 1,4 - D i c h l o r o b e n z e n e 1, 1 - D i c h l o r o e t h a n e 1, 2 - D i c h l o r o e t h a n e 1, 1 - D i c h l o r o e t h e n e 1,2 - D i c h l o r o p r o p a n e cis - 1 , 2 - D i c h l o r o e t h e n e Et h y l b e n z e n e Me t h y l e n e C h l o r i d e tr a n s - 1 , 2 - D i c h l o r o e t h e n e Te t r a c h l o r o e t h e n e To l u e n e To t a l X y l e n e s 1,1 , 1 - T r i c h l o r o e t h a n e Tr i c h l o r o e t h e n e Tr i c h l o r o f l u o r o m e t h a n e Vi n y l C h l o r i d e Te t r a h y d r o f u r a n 6,000 1 4,000 50 3,000 70 20 6 6 0.4 7 0.6 70 600 5 100 0.7 600 500 200 3 2,000 0.03 NE 100 1 100 3 10 5 5 1 5 1 5 1 5 1 1 5 1 1 5 1 1 1 1 NE CD-1s 25-Sep-06 CD-1s 31-Oct-06 CD-1s 23-Apr-07 CD-1s 29-Oct-07 CD-1s 23-Apr-08 0.40J CD-1s 18-Nov-08 1.1 CD-1s 8-Apr-09 CD-1s 13-Oct-09 CD-1s 11-May-10 CD-1s 2-Nov-10 CD-1s 3-May-11 CD-1s 8-Nov-11 CD-1s 7-May-12 CD-1s 27-Nov-12 0.4J 0.2J CD-1s 7-May-13 CD-1s 17-May-16 CD-1s 1-Nov-16 CD-1d 4-Oct-06 CD-1d 31-Oct-06 CD-1d 23-Apr-07 CD-1d 29-Oct-07 CD-1d 23-Apr-08 0.43J CD-1d 18-Nov-08 1.2 CD-1d 8-Apr-09 CD-1d 13-Oct-09 CD-1d 11-May-10 CD-1d 2-Nov-10 CD-1d 3-May-11 CD-1d 8-Nov-11 CD-1d 7-May-12 CD-1d 27-Nov-12 CD-1d 7-May-13 CD-1d 17-May-16 CD-1d 1-Nov-16 CD-2 25-Sep-06 CD-2 31-Oct-06 CD-2 23-Apr-07 CD-2 29-Oct-07 CD-2 22-Apr-08 0.57J 0.29J 0.34J CD-2 18-Nov-08 1.2B CD-2 8-Apr-09 CD-2 13-Oct-09 CD-2 11-May-10 CD-2 2-Nov-10 CD-2 3-May-11 CD-2 8-Nov-11 CD-2 7-May-12 CD-2 27-Nov-12 0.4J CD-2 7-May-13 CD-2 17-May-16 CD-2 1-Nov-16 CD-3 26-Sep-06 CD-3 31-Oct-06 CD-3 23-Apr-07 CD-3 29-Oct-07 CD-3 22-Apr-08 0.32J 0.35J CD-3 18-Nov-08 1.2B CD-3 8-Apr-09 CD-3 13-Oct-09 0.5J CD-3 11-May-10 CD-3 2-Nov-10 CD-3 3-May-11 CD-3 8-Nov-11 16J CD-3 22-Mar-12 CD-3 7-May-12 CD-3 27-Nov-12 0.4J CD-3 7-May-13 CD-3 17-May-16 0.6J 2.1J CD-3 1-Nov-16 0.6J 5.9 CD-4 Rep 23-Jan-09 .16J .78J CD-4 Rep 4-Nov-10 CD-4 Rep 3-May-11 CD-4 Rep (dup)3-May-11 CD-4 Rep 8-Nov-11 CD-4 Rep 8-May-12 CD-4 Rep 28-Nov-12 0.3J CD-4 Rep 9-May-13 CD-4 Rep 17-May-16 CD-4 Rep 2-Nov-16 CD-4 8-Aug-06 8 51 41 1 3 CD-4 26-Sep-06 3 41 24 1 2 1 CD-4 31-Oct-06 32 14 CD-4 23-Apr-07 0.42J 2.01J 0.37J 41 0.49J 0.48J 4 1 3 CD-4 29-Oct-07 1 4.93J 0.65J 69 0.59J 0.43J 9 2 0.31J 1.1J 4 CD-4 22-Apr-08 0.50J 2.87J 0.38J 45 0.37J 5 1 2 CD-4 20-Nov-08 0.6J 4.8J 0.4J 48 0.7J 0.5J 4.2 1.4 0.1J 2.6 0.3J CD-4 9-Apr-09 29 0.5J 3.4B 1.0 1.6 CD-4 14-Oct-09 2J 38 0.5J 0.5J 2.3 1.8 2.4 CD-4 6-May-10 0.3J 2.4J 0.2J 0.6J 40 0.6J 0.6J 4.7 2.4 2.8 0.3J North Carolina 2L Standard Solid Waste Section Limit 13-02 13-02 13-02 13-02 13-02 13-02 Page 1 of 4 Table 3-9 Table 3-9 Groundwater Quality Data Summary Cabarrus County C&D Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Fa c i l i t y P e r m i t N u m b e r Mo n i t o r i n g W e l l C o d e Sa m p l e D a t e Ac e t o n e Be n z e n e 2- B u t a n o n e Ch l o r o b e n z e n e Ch l o r o e t h a n e Ch l o r o f o r m 1,2 - D i c h l o r o b e n z e n e 1,4 - D i c h l o r o b e n z e n e 1, 1 - D i c h l o r o e t h a n e 1, 2 - D i c h l o r o e t h a n e 1, 1 - D i c h l o r o e t h e n e 1,2 - D i c h l o r o p r o p a n e cis - 1 , 2 - D i c h l o r o e t h e n e Et h y l b e n z e n e Me t h y l e n e C h l o r i d e tr a n s - 1 , 2 - D i c h l o r o e t h e n e Te t r a c h l o r o e t h e n e To l u e n e To t a l X y l e n e s 1,1 , 1 - T r i c h l o r o e t h a n e Tr i c h l o r o e t h e n e Tr i c h l o r o f l u o r o m e t h a n e Vi n y l C h l o r i d e Te t r a h y d r o f u r a n 6,000 1 4,000 50 3,000 70 20 6 6 0.4 7 0.6 70 600 5 100 0.7 600 500 200 3 2,000 0.03 NE 100 1 100 3 10 5 5 1 5 1 5 1 5 1 1 5 1 1 5 1 1 1 1 NE North Carolina 2L Standard Solid Waste Section Limit CD-5 26-Sep-06 2 9 95 6 2 11 2 CD-5 31-Oct-06 12 59 6 CD-5 23-Apr-07 4.87J 59 0.73J 2.6J 2 2 6 0.36J CD-5 29-Oct-07 0.41J 1.65J 47 1.8J 0.44J 0.36J 3 CD-5 22-Apr-08 0.77J 0.14J 3.79J 81 0.35J 3.86J 0.38J 0.54J 0.42J 7 0.28J 0.58J CD-5 20-Nov-08 0.8J 6.4J 55 0.3J 3.3J 0.5J 0.4J 0.5J 5.9 0.4J 0.8J CD-5 9-Apr-09 31J 0.6J 25 30 3.4J 1.2B 0.4J 3.4 1.3 CD-5 14-Oct-09 39J 1.2 73 61 13 0.4J 0.8J 2.9 2.2 CD-5 6-May-10 12J 0.9J 33 0.4J 180 0.7J 18 2.0J 0.9J 17 0.6J 5.9 CD-6 26-Sep-06 1 CD-6 31-Oct-06 CD-6 23-Apr-07 0.37J 0.87J CD-6 29-Oct-07 CD-6 22-Apr-08 0.34J 0.80J 0.53J 0.19J CD-6 19-Nov-08 CD-6 7-Apr-09 0.6J CD-6 14-Oct-09 11J 0.3J CD-6 11-May-10 0.5J CD-6 2-Nov-10 0.3J 0.7J CD-6 3-May-11 0.7J 0.9J CD-6 8-Nov-11 1.7J 1.4 0.6J CD-6 22-Mar-12 1.86 1.5 CD-6 8-May-12 2.2J 1.7 0.9J CD-6 28-Nov-12 2.8J 0.4J 1.2 0.8J CD-6 9-May-13 3.6J 1.6 1 CD-6 17-May-16 1.5J 0.5J 0.7J CD-6 1-Nov-16 2.2J 0.6J 0.9J 13-02 MW-2 3-May-12 4.47J 0.14J 0.22J 0.17J 13-02 B-1s 22-Mar-12 B-1s 3-May-12 0.59J B-1s 4-Aug-16 0.62J 13-02 B-1d 22-Mar-12 1.96 2.46 16.4 3.54 2.20 1.29 B-1d 3-May-12 0.67J 0.53J 1.96 2.47 16.2 0.24J 0.30J 3.64 0.62J 2.38 1.37 B-1d 4-Aug-16 1.50 1.1J 7.2 0.69J 1.60 13-02 B-3 25-Jun-03 24 16 48 19 16 26 12 B-3 3-May-12 4.98 5 0.74J 1.14 24.3 4.83 1.73 1.35 57.3 20 0.67J 1.31 33.4 35 1.35 1.83 B-3 4-Aug-16 4.5 3.8 1.1J 23 2.3J 1.20 0.71J 30 41 0.67J 71 120 2.0 2.3 13-02 B-4 11-Jun-03 7 10 10 6 B-4 3-May-12 0.76J 0.72J 5.1 0.68J 11.2 0.13J 0.44J 2.87 0.36J 1.06J 5.17 0.79J B-4 4-Aug-16 2.1 0.98J 1.5 5.8 29 2 0.46J 1.5 6.1 6.4 5.1 0.67J 13-02 B-5 25-Jun-03 B-5 3-May-12 0.220J 1.33 0.590J B-5 4-Aug-16 3.5J 0.71J 5.2 1.1 13-02 B-6 25-Jun-03 8 20 8 120 160 72 18 B-6 3-May-12 1.09 2.06 0.48J 7.20 14.1 67.6 3.14 0.61J 3.01 182 0.19J 0.62J 3.04 1.28 0.75J 14.1 8.96 B-6 4-Aug-16 1.4 0.41J 2.6J 10 54 2.8 2.6 130 2.5J 0.71J 0.96J 3.3 3.1 13-02 B-7 22-Mar-12 B-7 3-May-12 0.65J 0.67J B-7 (CD-7)17-May-16 0.7J 1.0J B-7 (CD-7)1-Nov-16 1.2J 1.7J 13-02 B-17s 22-Jan-09 1.25J 5.2J 108 4.3J 4.9J 1.95J 5.75 13-02 B-17d 23-Jan-09 0.96J 3.54J 0.68J 66.7 3.32J 4.72 1.24J 4.54 B-18s 23-Jan-09 2.14 0.72J 1.18J 4.28J 28 1.38J 52.8 0.68J 0.74J 7.64 0.22J 0.46 27.4 1.78 B-18s 22-Mar-12 1.61 4.93 6.10 13.3 1.21 77.9 1.99 B-18s 3-May-12 15.3J 1.64 0.71J 3.93 6.83 12.5 0.79J 1.24 81.4 0.39J 0.72J 0.29J 0.53J 0.56J 1.59 B-18s 4-Aug-16 37J 0.64J 0.70J 2.2J 6.7 4.8J 0.94J 50 0.48J 1.2 1.3 B-18d 23-Jan-09 3.13J 1.46 0.17J 1.26J 4.23J 1.74J 33.1 42.5 0.73J 0.78J 8.3 0.15J 25.4 2.33 B-18d 22-Mar-12 1.84 2.22 4.20 28.9 1.30 94.4 1.17 1.04 18.3 2.68 B-18d 3-May-12 2.08 0.43J 2.31 4.17 31.4 1.06 0.27J 1.33 97.7 0.38J 1.35 1.88 0.24J 21.9 2.83 B-18d 4-Aug-16 1.1 0.52J 1.6J 4.9 20 1.3 0.96J 87 1.0J 7.1 1.0 B-19 22-Jan-09 0.22J 3.34J 2.84J 0.89J 2.2 1.21 B-19 22-Mar-12 1.13 2.24 1.03 B-19 3-May-12 0.18J 0.80J 1.51 0.90J B-19 (CD-8)4-Aug-16 B-19 (CD-8)1-Nov-16 13-02 13-02 13-02 13-02 13-02 Page 2 of 4 Table 3-9 Table 3-9 Groundwater Quality Data Summary Cabarrus County C&D Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Fa c i l i t y P e r m i t N u m b e r Mo n i t o r i n g W e l l C o d e Sa m p l e D a t e Ac e t o n e Be n z e n e 2- B u t a n o n e Ch l o r o b e n z e n e Ch l o r o e t h a n e Ch l o r o f o r m 1,2 - D i c h l o r o b e n z e n e 1,4 - D i c h l o r o b e n z e n e 1, 1 - D i c h l o r o e t h a n e 1, 2 - D i c h l o r o e t h a n e 1, 1 - D i c h l o r o e t h e n e 1,2 - D i c h l o r o p r o p a n e cis - 1 , 2 - D i c h l o r o e t h e n e Et h y l b e n z e n e Me t h y l e n e C h l o r i d e tr a n s - 1 , 2 - D i c h l o r o e t h e n e Te t r a c h l o r o e t h e n e To l u e n e To t a l X y l e n e s 1,1 , 1 - T r i c h l o r o e t h a n e Tr i c h l o r o e t h e n e Tr i c h l o r o f l u o r o m e t h a n e Vi n y l C h l o r i d e Te t r a h y d r o f u r a n 6,000 1 4,000 50 3,000 70 20 6 6 0.4 7 0.6 70 600 5 100 0.7 600 500 200 3 2,000 0.03 NE 100 1 100 3 10 5 5 1 5 1 5 1 5 1 1 5 1 1 5 1 1 1 1 NE North Carolina 2L Standard Solid Waste Section Limit MW-A 16-Sep-94 MW-A 18-Oct-94 MW-A 19-Dec-94 MW-A 14-Feb-95 MW-A 10-Jun-95 33 MW-A 24-Oct-95 MW-A 13-Nov-95 143 MW-A 25-Jan-96 182 MW-A 6-Dec-96 100 MW-A 4-May-97 17 9 7 78 MW-A 6-Nov-97 5.6 19 8 11 33 MW-A 20-Apr-98 13 13 16 9 14 26 MW-A 10-Nov-98 10 19 7.5 16 7 6 17 8.0 MW-A (dup)10-Nov-98 12 19 7.1 21 7 6 19 11 MW-A 1-Apr-99 22 30 12 10 7 16 6 MW-A 16-Nov-99 15 27 13 12 18 7 MW-A 26-Apr-00 6 22 42 28 5 11 21 7 MW-A 27-Sep-00 8 23 53 44 14 13 19 5 MW-A 8-May-01 9 20 58 53 13 12 20 5 MW-A (dup)8-May-01 8 19 59 53 13 12 21 6 MW-A 30-Oct-01 9 23 60 56 10 15 12 18 MW-A 23-Apr-02 9 22 72 59 14 14 12 18 13 MW-A 15-Oct-02 10 23 77 62 20 15 12 16 MW-A 23-Apr-03 14 31 150 96 45 24 19 23 MW-A 23-Oct-03 13 26 100 80 64 18 13 17 MW-A 21-Apr-04 12 24 94 92 46 18 8 18 MW-A 20-Oct-04 11 22 89 90 47 16 8 17 MW-A (dup)20-Oct-04 10 22 91 91 49 17 6.8 16 MW-A 25-Apr-05 13 26 100 110 62 21 9 18 MW-A 25-Oct-05 11 67 61 100 52 16 8 14 MW-A 18-Apr-06 11 16 69 110 67 14 13 MW-A 30-Oct-06 12 39 6 64 130 74 13 5 12 MW-A 23-Apr-07 12 12 10 71 0.45J 0.35J 3 120 14 0.84J 12 0.59J 7 11 0.34J 0.35J MW-A 30-Oct-07 11 1.23J 12 49 2 140 15 1.15J 10 8 9 1 MW-A 22-Apr-08 10 0.63J 9.84J 11 42 0.61J 0.18J 3 150 17 0.54J 7 0.20J 4.06J 6 0.24J 1 MW-A (dup)22-Apr-08 11 1.02J 18 11 37 0.20J 3 150 14 0.88J 9 0.48J 8 8 0.32J 3 MW-A 20-Nov-08 7.4 11 12 31 0.8J 2.8 100 1 0.6J 5.2 5.7 4.7 0.2J 0.8J MW-A 9-Apr-09 7.8 1.1JB 11 15 29 0.8J 2.9 120 1.9B 0.8J 6.2 6.8 5.4 1J MW-A 16-Oct-09 13J 8.9 14 16 27 140 0.4J 0.4J 5.4 7.8 4.3 1 MW-A 7-May-10 8.7 0.8J 17 14 19 2.1 0.2J 2.9 130 0.4J 4.6 0.3J 9.3 3.5 1.2 MW-A 2-Nov-10 8.3 5.3J 17 15 2.1 2.5 120 0.5J 5.4 3.1J 3.8 1.2 MW-A (dup)2-Nov-10 6.9 4.8J 15 14 1.9 2.2 110 0.4J 4.8 2.9J 3.4 0.2J 1 MW-A 3-May-11 7.4 1J 4.7J 12 14 2.2 2.2 110 0.8J 0.4J 3.9 3.1J 3.2 0.7J MW-A 9-Nov-11 9.2 1.4J 6.5J 16 18 2.8 2.4 120 2 0.6J 6.5 5.2 3.8 1J MW-A 9-May-12 8.8 1.1J 6.5J 17 26 3.8 0.5J 2.0 110 0.9J 0.4J 6.5 2.6J 0.5J 4.5 0.2J 1.1 MW-A 27-Nov-12 9.3 1.6J 6.9J 15 25 3.9 0.6J 2.2 130 0.4J 0.5J 0.5J 4.7 1.7J 0.4J 4.4 0.8J MW-A 7-May-13 9.1 1.3J 5.1J 22 23 3 0.4J 2.4 120 0.6J 0.8J 0.5J 6.2 0.3J 8 4.3 MW-A 17-May-16 9.7 1.5J 31 15 1.3 2.2 120 1.1 1 4.8 0.6J 5.2 3.7 0.8J MW-A 1-Nov-16 11 1.6J 5.7J 36 17 1.6 2.6 140 0.7J 1 0.5J 5.7 4.7J 3.8 0.9J MW-J 19-Nov-99 MW-J 26-Apr-00 MW-J 27-Sep-00 MW-J 9-May-01 MW-J 30-Oct-01 MW-J 23-Apr-02 MW-J 14-Oct-02 MW-J 24-Apr-03 MW-J 23-Oct-03 MW-J 21-Apr-04 MW-J 20-Oct-04 MW-J 26-Apr-05 MW-J 25-Oct-05 MW-J 18-Apr-06 MW-J 30-Oct-06 MW-J 23-Apr-07 MW-J 30-Oct-07 MW-J 21-Apr-08 0.48J 0.29J MW-J 19-Nov-08 MW-J 7-Apr-09 MW-J 16-Oct-09 MW-J 11-May-10 MW-J 2-Nov-10 MW-J 3-May-11 MW-J 8-Nov-11 MW-J 8-May-12 MW-J 28-Nov-12 0.8J MW-J 7-May-13 MW-J 17-May-16 MW-J 1-Nov-16 13-02 13-02 Page 3 of 4 Table 3-9 Table 3-9 Groundwater Quality Data Summary Cabarrus County C&D Landfill - Phase 3 and 4 Expansion Design Hydrogeologic Investigation Fa c i l i t y P e r m i t N u m b e r Mo n i t o r i n g W e l l C o d e Sa m p l e D a t e Ac e t o n e Be n z e n e 2- B u t a n o n e Ch l o r o b e n z e n e Ch l o r o e t h a n e Ch l o r o f o r m 1,2 - D i c h l o r o b e n z e n e 1,4 - D i c h l o r o b e n z e n e 1, 1 - D i c h l o r o e t h a n e 1, 2 - D i c h l o r o e t h a n e 1, 1 - D i c h l o r o e t h e n e 1,2 - D i c h l o r o p r o p a n e cis - 1 , 2 - D i c h l o r o e t h e n e Et h y l b e n z e n e Me t h y l e n e C h l o r i d e tr a n s - 1 , 2 - D i c h l o r o e t h e n e Te t r a c h l o r o e t h e n e To l u e n e To t a l X y l e n e s 1,1 , 1 - T r i c h l o r o e t h a n e Tr i c h l o r o e t h e n e Tr i c h l o r o f l u o r o m e t h a n e Vi n y l C h l o r i d e Te t r a h y d r o f u r a n 6,000 1 4,000 50 3,000 70 20 6 6 0.4 7 0.6 70 600 5 100 0.7 600 500 200 3 2,000 0.03 NE 100 1 100 3 10 5 5 1 5 1 5 1 5 1 1 5 1 1 5 1 1 1 1 NE North Carolina 2L Standard Solid Waste Section Limit MW-X 10-Nov-98 MW-X 19-Nov-99 MW-X 23-Oct-03 MW-X 21-Apr-04 MW-X 20-Oct-04 MW-X 26-Apr-05 MW-X 25-Oct-05 MW-X 18-Apr-06 MW-X 30-Oct-06 MW-X 23-Apr-07 MW-X 30-Oct-07 MW-X 21-Apr-08 0.39J MW-X 19-Nov-08 MW-X 7-Apr-09 MW-X 15-Oct-09 MW-X 11-May-10 MW-X 3-Nov-10 MW-X 3-May-11 MW-X 8-Nov-11 MW-X 8-May-12 MW-X 28-Nov-12 0.6J MW-X (dup)28-Nov-12 0.6J MW-X 7-May-13 MW-X 17-May-16 MW-X 1-Nov-16 Notes: 1. All units are in micrograms per liter (parts per billion). 2. Assessment Wells CD-4, CD-5, and CD-6 were installed in September 2006. 3. Assessment Wells CD-4 and CD-5 were abandoned in July 2010. 4. J - Indicates the analytical result is an estimated concentration between the method detection limit and the Solid Waste Section Reporting Limit. 5. B - Indicates constituent was detected in the batch blank above the method detection limit. 6. The November 2012 sampling event was the first event that CD-1s/CD-1d replaced MW-9 as the background monitoring wells. 7. MW-9 was removed from the monitoring program in November 2012. - Concentration exceeds North Carolina 2L Groundwater Standard - Indicates result below detection limit 13-02 Page 4 of 4 Table 3-9 4-1 (revised January 2017) Section 4 Conclusions This section presents conclusions based upon site investigation activities to date. These conclusions include considerations regarding the landfill design and considerations for the water quality monitoring plan. 4.1 Landfill Construction Considerations Based on the findings of presented in this report and previous reports, the C&D Landfill Phase 3 and 4 expansion areas are considered to be suitable for expansion of the Cabarrus County C&D Landfill facility. Similar to previous investigations for existing C&D, the following issues should be considered in the landfill design. Provisions must be made such that the expansions can be monitored separately from the closed MSW landfill. This will accomplished by utilizing existing monitoring wells and piezometers installed during previous investigations. The separation between the base of the landfill and the seasonal high water table surface or top of bedrock is not a concern for the Phase 3 or Phase 4 expansions due to the spatial limitations. Excavation beyond the existing ground surface will be minimal in the Phase 3 and 4 areas. After construction and final closure of the landfill, groundwater recharge will be expected to decrease due to the placement of a landfill cap in addition to improved run-off control, thus, reducing precipitation available for infiltration. This reduction in groundwater recharge may cause a lowering in the water table surface downgradient of the C&D landfill; however, no change of direction of groundwater flow is anticipated. With the decrease in the water table surface, a decrease in the hydraulic gradient beneath the landfill will occur. This will decrease the groundwater flow velocity and therefore increase the attenuation time for the existing groundwater contamination coming from the Unit 2 and 3 MSW landfill. 4.2 Water Quality Monitoring Plan Considerations The Phase 3 and 4 Expansion areas will be small and can be monitored with existing C&D monitoring wells in addition to installation of one additional down-gradient monitoring point, as described in the accompanying Water Quality Monitoring Plan. 4.3 Piezometer and Monitoring Well Abandonment All borings and monitoring wells intersecting groundwater at the site during this investigation have been constructed and maintained as permanent monitoring wells in accordance with NCAC 02C .0108. Section 4 • Conclusions 4-2 (revised January 2017) Rule .0538(b)(2)(J) requires that all borings at the site not converted to permanent monitoring wells shall be properly abandoned in accordance with the NCAC 02C .0113. Existing monitoring wells CD-3, CD-6, and CD-8 as well as existing piezometers B-1s/-1d and B-18s/-18d will be abandoned prior to construction of each expansion. Monitoring well CD-8 will be temporarily re- located down-gradient of the Phase 3 expansion. The remaining existing piezometers (B-3, B-4, B- 5, and B-6) that were installed during previous investigations will remain in order to assess groundwater conditions associated with the Unit 2 and 3 MSW landfill, as needed. 5-1 Section 5 References ASTM (American Society of Testing and Materials). Annual Book of Standards. Bouwer, H. 1989. The Bouwer and Rice Method - An Update. Groundwater. pp. 304-309. May - June. CDM (Camp Dresser & McKee). 1994. Cabarrus County, North Carolina, Draft Report, Landfill Expansion Study, Appendix E, CDM Draft Report “Onsite Investigations of Potential Landfill Expansion Sites,” Cabarrus County, North Carolina. September. CDM, 1994. Cabarrus County, North Carolina, Cabarrus County Sanitary Landfill, Initial Baseline Sampling Report. October. CDM, 2000. Cabarrus County, North Carolina, Cabarrus County Sanitary Landfill, Groundwater Assessment Report (Units 2&3). October. CDM, 2005. Cabarrus County, North Carolina, Proposed Construction and Demolition Landfill Expansion, Design Hydrogeologic Report. January. CDM, 2008. Cabarrus County, North Carolina, Cabarrus County Sanitary Landfill Units 2 and 3, Facility Permit #1302, Assessment of Corrective Measures Report. December. CDM, 2009. Cabarrus County, North Carolina, Cabarrus County Sanitary Landfill Units 2 and 3, Facility Permit #1302, Corrective Action Plan. Revised August. CDM Smith, 2013. Proposed Cabarrus County C&D Landfill Expansion, Alternate Source Demonstration, Facility Permit # 1302. September. CDM Smith, 2013. Cabarrus County C&D Landfill. Substantial Amendment and Phase 2 Permit to Construct Application. December. Daniel, III, C.C. 1987. Statistical Analysis Relating Well Yield to Construction Practices and Siting of Wells in the Piedmont and Blue Ridge Provinces of North Carolina. USGS Water Resources Report 86-4132. Driscoll, F.G. 1986. Groundwater and Wells. 2nd Edition. pp. 252-260. Gair, J.E., 1989. Mineral Resources of the Charlotte 1x2 Quadrangle, North Carolina and South Carolina, USGS Prof. Paper 1462, Geology of the Charlotte Quadrangle, p. 7-15. Goldsmith, R. et.al., 1988. Geologic Map of the Charlotte 1x2 Quadrangle, North Carolina and South Carolina, USGS Miscellaneous Map Series Map I-251E, 1:250,000. Section 5 • References 5-2 Heath, Ralph C. 1980. Basic Elements of Ground-Water Hydrology With References to Conditions in North Carolina. U.S. Geological Survey Water Resources Investigations. Open-File Report 80- 44. Hicks, H.T., 1985. Diabase Dikes – Subterranean Water Reservoirs in the Deep River Triassic Basin of North Carolina. U.S. Geological Survey Water Resources Investigations. Open File Report 80-44. Johnson, A.I. 1967. Specific Yields for Geologic Materials. USGS Water Supply Paper 1662-D. NCGS (North Carolina Geological Survey). 1985. Geologic Map of North Carolina.                   Appendix B  Geotechnical Laboratory Data                       Appendix D  Slug Test Raw Data and Calculations     Te r m U n i t s 2r c In c h e s 2. 0 6 7 2r W In c h e s 8 L w Fe e t 7. 6 L e Fe e t 10 H* Fe e t 7. 6 y 0 Fe e t 0. 2 4 t 0 Se c o n d s 0 y t Fe e t 0. 0 0 1 t Se c o n d s 1, 5 4 0 Te r m U n i t s Wa t e r T a b l e Wa t e r T a b l e 2r c y In p u t D a t a 3.15E-06 Ca l c u l a t i o n s Solutions 2.390 Hy d r a u l i c C o n d u c t i v i t y i n F e e t / S e c o n d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / D a y 2.72E-01 * - A s s u m e d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / M i n u t e 1.89E-04 L e /r W Fe e t / F o o t 3 0 . 0 0 A No n e 2 . 4 7 5 B N o n e 0 . 3 7 4 C N o n e 2 . 0 0 1 1 y 0 t y t Wh e r e 2r w B- 1 7 s F a l l - S l u g T e s t C a l c u l a t i o n s Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Im p e r m e a b l e ln ( R e / r W ) = { 1. 1 + C L e /r W} -1 ln ( L W /r W ) A Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n Fo r p a r t i a l p e n e t r a t i o n o r t h e e q u a t i o n b e l o w f o r f u l l p e n e t r a t i o n } -1 L e /r W 1. 1 ln ( L W /r W ) + ln ( R e / r W ) = { S c r e e n L w L e H B o r e h o l e B o r e h o l e ln Ge n e r a l E q u a t i o n s ln ( R e /r W )partial penetration = ln ( R e /r W )full penetration =2.390#NUM! K = A + B l n [ ( H - L W )/r W ] r c2 l n ( R e /r W ) 2L e 110 Y 0 ( f e e t )A Ti m e ( s e c ) B-17s Fall Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 0. 0 0 1 0. 0 1 0. 1 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 B ‐17s  Fall In-Situ Inc.MiniTroll Pro Report generated:1/26/2009 16:53:07 Report from file:...\SN07563 2009-01-23 180121 B-17s In.bin Win-Situ® Version 4.58.9.0 Serial number:7563 Firmware Version 3.09 Unit name: Test name:B-17s In Test defined on:1/23/2009 18:00:32 Test started on:1/23/2009 18:01:21 Test stopped on:N/A N/A Data gathered using Logarithmic testing Maximum time between data points: 4200.0Seconds. Number of data samples:129 TOTAL DATA SAMPLES 129 Channel number [1] Measurement type:Temperature Channel name: Channel number [2] Measurement type:Pressure Channel name:depth Sensor Range: 30 PSIG. Sensor Offset:0.000 psi Specific gravity:1 Mode:TOC User-defined reference:0 Feet H2O Referenced on:test start Pressure head at reference:6.487 Feet H2O ET (sec)Feet H2O yt (feet) --------------------------- 000 0.3 -0.006 0.006 0.6 -0.012 0.012 0.9 -1.107 1.107 1.2 -3.948 3.948 1.5 -1.411 1.411 1.8 -0.714 0.714 2.1 -0.132 0.132 2.4 -1.25 1.25 2.7 -1.286 1.286 3 -0.176 0.176 3.3 -0.17 0.17 3.6 -0.664 0.664 3.9 -0.364 0.364 4.2 -0.109 0.109 4.5 -0.332 0.332 4.8 -0.33 0.33 5.1 -0.197 0.197 5.4 -0.256 0.256 5.7 -0.288 0.288 B-17s Fall Data 6 -0.233 0.233 6.4 -0.248 0.248 6.7 -0.256 0.256 7.1 -0.239 0.239 7.5 -0.25 0.25 8 -0.245 0.245 8.4 -0.241 0.241 8.9 -0.245 0.245 9.5 -0.243 0.243 10 -0.237 0.237 10.6 -0.235 0.235 11.3 -0.233 0.233 11.9 -0.233 0.233 12.6 -0.233 0.233 13.4 -0.229 0.229 14.2 -0.229 0.229 15 -0.226 0.226 15.9 -0.226 0.226 16.8 -0.224 0.224 17.8 -0.226 0.226 18.9 -0.224 0.224 20 -0.224 0.224 21.2 -0.224 0.224 22.4 -0.222 0.222 23.8 -0.222 0.222 25.2 -0.22 0.22 26.7 -0.222 0.222 28.2 -0.222 0.222 29.8 -0.22 0.22 31.5 -0.218 0.218 33.3 -0.218 0.218 35.2 -0.218 0.218 37.3 -0.215 0.215 39.5 -0.215 0.215 41.8 -0.215 0.215 44.3 -0.215 0.215 46.9 -0.215 0.215 49.7 -0.215 0.215 52.6 -0.215 0.215 55.7 -0.213 0.213 59 -0.213 0.213 62.5 -0.211 0.211 66.2 -0.213 0.213 70.1 -0.211 0.211 74.3 -0.213 0.213 78.7 -0.21 0.21 83.4 -0.21 0.21 88.4 -0.21 0.21 93.7 -0.21 0.21 99.3 -0.208 0.208 105.2 -0.208 0.208 111.5 -0.208 0.208 118.1 -0.21 0.21 125.1 -0.208 0.208 132.6 -0.208 0.208 140.5 -0.208 0.208 148.9 -0.205 0.205 157.8 -0.207 0.207 167.2 -0.205 0.205 177.2 -0.203 0.203 187.8 -0.203 0.203 B-17s Fall Data 199 -0.2 0.2 210.9 -0.2 0.2 223.5 -0.203 0.203 236.8 -0.2 0.2 250.9 -0.2 0.2 265.8 -0.2 0.2 281.6 -0.2 0.2 298.4 -0.196 0.196 316.2 -0.196 0.196 335 -0.196 0.196 354.9 -0.194 0.194 376 -0.192 0.192 398.4 -0.191 0.191 422.1 -0.189 0.189 447.2 -0.187 0.187 473.8 -0.187 0.187 502 -0.185 0.185 531.9 -0.181 0.181 563.5 -0.181 0.181 597 -0.179 0.179 632.5 -0.177 0.177 670.1 -0.175 0.175 709.9 -0.172 0.172 752.1 -0.17 0.17 796.8 -0.168 0.168 844.2 -0.166 0.166 894.4 -0.162 0.162 947.5 -0.16 0.16 1003.8 -0.157 0.157 1063.4 -0.155 0.155 1126.6 -0.153 0.153 1193.5 -0.151 0.151 1264.4 -0.147 0.147 1339.5 -0.145 0.145 1419 -0.14 0.14 1503.3 -0.138 0.138 1592.6 -0.138 0.138 1687.1 -0.136 0.136 1787.2 -0.132 0.132 1893.3 -0.13 0.13 2005.7 -0.127 0.127 2124.7 -0.123 0.123 2250.8 -0.121 0.121 2384.4 -0.119 0.119 2525.9 -0.119 0.119 2675.8 -0.115 0.115 2834.6 -0.113 0.113 3002.8 -0.113 0.113 B-17s Fall Data Te r m U n i t s 2r c In c h e s 2. 0 6 7 2r W In c h e s 8 L w Fe e t 7. 6 L e Fe e t 10 H* Fe e t 7. 6 y 0 Fe e t 0. 0 8 8 t 0 Se c o n d s 0 y t Fe e t 0. 0 0 1 t Se c o n d s 1, 0 9 0 Te r m U n i t s Wa t e r T a b l e Wa t e r T a b l e 2r c y In p u t D a t a 3.64E-06 Ca l c u l a t i o n s Solutions 2.390 Hy d r a u l i c C o n d u c t i v i t y i n F e e t / S e c o n d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / D a y 3.15E-01 * - A s s u m e d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / M i n u t e 2.18E-04 L e /r W Fe e t / F o o t 3 0 . 0 0 A No n e 2 . 4 7 5 B N o n e 0 . 3 7 4 C N o n e 2 . 0 0 1 1 y 0 t y t Wh e r e 2r w B- 1 7 s R e c o v e r y - S l u g T e s t C a l c u l a t i o n s Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Im p e r m e a b l e ln ( R e / r W ) = { 1. 1 + C L e /r W} -1 ln ( L W /r W ) A Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n Fo r p a r t i a l p e n e t r a t i o n o r t h e e q u a t i o n b e l o w f o r f u l l p e n e t r a t i o n } -1 L e /r W 1. 1 ln ( L W /r W ) + ln ( R e / r W ) = { S c r e e n L w L e H B o r e h o l e B o r e h o l e ln Ge n e r a l E q u a t i o n s ln ( R e /r W )partial penetration = ln ( R e /r W )full penetration =2.390#NUM! K = A + B l n [ ( H - L W )/r W ] r c2 l n ( R e /r W ) 2L e 110 Y 0 ( f e e t )A Ti m e ( s e c ) B-17s Recovery Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 0. 0 0 1 0. 0 1 0. 1 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 B ‐17s  Recovery In-Situ Inc.MiniTroll Pro Report generated:1/26/2009 16:53:56 Report from file:...\SN07563 2009-01-23 185441 B-17s Out.bin Win-Situ® Version 4.58.9.0 Serial number:7563 Firmware Version 3.09 Unit name: Test name:B-17s Out Test defined on:1/23/2009 18:54:18 Test started on:1/23/2009 18:54:41 Test stopped on:N/A N/A Data gathered using Logarithmic testing Maximum time between data points: 4200.0Seconds. Number of data samples:130 TOTAL DATA SAMPLES 130 Channel number [1] Measurement type:Temperature Channel name: Channel number [2] Measurement type:Pressure Channel name:depth Sensor Range: 30 PSIG. Sensor Offset:0.000 psi Specific gravity:1 Mode:TOC User-defined reference:0 Feet H2O Referenced on:test start Pressure head at reference:3.453 Feet H2O ET (sec)Feet H2O yt (feet) --------------------------- 000 0.6 -0.455 2.507 0.9 -2.526 0.436 1.2 -1.259 1.703 1.5 -2.266 0.696 1.8 -1.894 1.068 2.1 -2.175 0.787 2.4 -2.3 0.662 2.7 -2.215 0.747 3 -2.523 0.439 3.3 -2.352 0.61 3.6 -2.61 0.352 3.9 -2.531 0.431 4.2 -2.645 0.317 4.5 -2.667 0.295 4.8 -2.671 0.291 5.1 -2.742 0.22 5.4 -2.717 0.245 5.7 -2.768 0.194 B-17s Recovery Data 6 -2.764 0.198 6.4 -2.787 0.175 6.7 -2.791 0.171 7.1 -2.81 0.152 7.5 -2.81 0.152 8 -2.825 0.137 8.4 -2.827 0.135 8.9 -2.833 0.129 9.5 -2.846 0.116 10 -2.844 0.118 10.6 -2.846 0.116 11.3 -2.848 0.114 11.9 -2.852 0.11 12.6 -2.855 0.107 13.4 -2.857 0.105 14.2 -2.863 0.099 15 -2.865 0.097 15.9 -2.867 0.095 16.8 -2.865 0.097 17.8 -2.871 0.091 18.9 -2.871 0.091 20 -2.876 0.086 21.2 -2.878 0.084 22.4 -2.88 0.082 23.8 -2.878 0.084 25.2 -2.88 0.082 26.7 -2.878 0.084 28.2 -2.882 0.08 29.8 -2.884 0.078 31.5 -2.882 0.08 33.3 -2.884 0.078 35.2 -2.886 0.076 37.3 -2.889 0.073 39.5 -2.89 0.072 41.8 -2.891 0.071 44.3 -2.893 0.069 46.9 -2.893 0.069 49.7 -2.895 0.067 52.6 -2.895 0.067 55.7 -2.897 0.065 59 -2.897 0.065 62.5 -2.897 0.065 66.2 -2.899 0.063 70.1 -2.899 0.063 74.3 -2.901 0.061 78.7 -2.901 0.061 83.4 -2.903 0.059 88.4 -2.904 0.058 93.7 -2.903 0.059 99.3 -2.906 0.056 105.2 -2.904 0.058 111.5 -2.906 0.056 118.1 -2.906 0.056 125.1 -2.908 0.054 132.6 -2.91 0.052 140.5 -2.908 0.054 148.9 -2.91 0.052 157.8 -2.91 0.052 167.2 -2.91 0.052 177.2 -2.912 0.05 187.8 -2.912 0.05 B-17s Recovery Data 199 -2.912 0.05 210.9 -2.914 0.048 223.5 -2.912 0.05 236.8 -2.914 0.048 250.9 -2.914 0.048 265.8 -2.914 0.048 281.6 -2.917 0.045 298.4 -2.917 0.045 316.2 -2.917 0.045 335 -2.919 0.043 354.9 -2.919 0.043 376 -2.921 0.041 398.4 -2.921 0.041 422.1 -2.921 0.041 447.2 -2.921 0.041 473.8 -2.921 0.041 502 -2.921 0.041 531.9 -2.923 0.039 563.5 -2.925 0.037 597 -2.925 0.037 632.5 -2.927 0.035 670.1 -2.929 0.033 709.9 -2.929 0.033 752.1 -2.929 0.033 796.8 -2.931 0.031 844.2 -2.931 0.031 894.4 -2.933 0.029 947.5 -2.933 0.029 1003.8 -2.933 0.029 1063.4 -2.935 0.027 1126.6 -2.935 0.027 1193.5 -2.937 0.025 1264.4 -2.942 0.02 1339.5 -2.941 0.021 1419 -2.943 0.019 1503.3 -2.943 0.019 1592.6 -2.946 0.016 1687.1 -2.945 0.017 1787.2 -2.945 0.017 1893.3 -2.947 0.015 2005.7 -2.949 0.013 2124.7 -2.952 0.01 2250.8 -2.952 0.01 2384.4 -2.954 0.008 2525.9 -2.956 0.006 2675.8 -2.958 0.004 2834.6 -2.96 0.002 3002.8 -2.96 0.002 3180.9 -2.962 0 B-17s Recovery Data Te r m U n i t s 2r c In c h e s 2. 0 6 7 2r W In c h e s 8 L w Fe e t 16 . 9 1 L e Fe e t 5 H* Fe e t 16 . 9 1 y 0 Fe e t 2. 6 t 0 Se c o n d s 0 y t Fe e t 0. 0 1 t Se c o n d s 3, 0 0 0 Te r m U n i t s 2.22E-04 In p u t D a t a 3.70E-06 Ca l c u l a t i o n s Solutions 2.690 Hy d r a u l i c C o n d u c t i v i t y i n F e e t / S e c o n d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / D a y 3.20E-01 * - A s s u m e d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / M i n u t e Wa t e r T a b l e Wa t e r T a b l e 2r c y L e /r W Fe e t / F o o t 1 5 . 0 0 A No n e 1 . 9 8 9 B N o n e 0 . 2 8 3 C N o n e 1 . 3 7 4 1 y 0 t y t Wh e r e 2r w K = A + B l n [ ( H - L W )/r W ] r c2 l n ( R e /r W ) 2L e ln Ge n e r a l E q u a t i o n s ln ( R e /r W )partial penetration = ln ( R e /r W )full penetration =2.690#NUM! S c r e e n L w L e H B o r e h o l e B o r e h o l e Fo r p a r t i a l p e n e t r a t i o n o r t h e e q u a t i o n b e l o w f o r f u l l p e n e t r a t i o n } -1 L e /r W 1. 1 ln ( L W /r W ) + ln ( R e / r W ) = { B- 1 7 d F a l l - S l u g T e s t C a l c u l a t i o n s Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Im p e r m e a b l e ln ( R e / r W ) = { 1. 1 + C L e /r W} -1 ln ( L W /r W ) A Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 110 Y 0 ( f e e t )A Ti m e ( s e c ) B-17d Fall Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 0. 0 1 0. 1 0 1 0 0 0 2 0 0 0 3 0 0 0 4 0 0 0 5 0 0 0 6 0 0 0 7 0 0 0 B ‐17d  Fall In-Situ Inc.MiniTroll Pro Report generated:1/26/2009 16:50:00 Report from file:...\SN04881 2009-01-23 151515 B-17d Slug In.bin Win-Situ® Version 4.58.9.0 Serial number:4881 Firmware Version 3.09 Unit name: Test name:B-17d Slug In Test defined on:1/23/2009 15:14:54 Test started on:1/23/2009 15:15:15 Test stopped on:N/A N/A Data gathered using Logarithmic testing Maximum time between data points: 4200.0Seconds. Number of data samples:142 TOTAL DATA SAMPLES 142 Channel number [1] Measurement type:Temperature Channel name:KS-6 weir Channel number [2] Measurement type:Pressure Channel name:KS-6 weir Sensor Range: 30 PSIG. Sensor Offset:0.000 psi Specific gravity:1 ET (sec)Feet H2O yt (feet) --------------------------- 0 13.987 0 0.3 17.124 3.103 0.6 18.103 4.082 1.2 16.457 2.436 1.5 17.068 3.047 1.8 16.233 2.212 2.1 16.861 2.84 2.4 16.481 2.46 2.7 16.679 2.658 3 16.631 2.61 3.3 16.603 2.582 3.6 16.631 2.61 3.9 16.611 2.59 4.2 16.611 2.59 4.5 16.611 2.59 4.8 16.603 2.582 5.1 16.603 2.582 5.4 16.599 2.578 5.7 16.598 2.577 B-17d Fall Data 6 16.598 2.577 6.4 16.592 2.571 6.7 16.592 2.571 7.1 16.59 2.569 7.5 16.588 2.567 8 16.587 2.566 8.4 16.585 2.564 8.9 16.583 2.562 9.5 16.581 2.56 10 16.576 2.555 10.6 16.574 2.553 11.3 16.572 2.551 11.9 16.568 2.547 12.6 16.567 2.546 13.4 16.565 2.544 14.2 16.563 2.542 15 16.546 2.525 15.9 16.554 2.533 16.8 16.555 2.534 17.8 16.555 2.534 18.9 16.552 2.531 20 16.548 2.527 21.2 16.544 2.523 22.4 16.543 2.522 23.8 16.541 2.52 25.2 16.537 2.516 26.7 16.535 2.514 28.2 16.532 2.511 29.8 16.528 2.507 31.5 16.524 2.503 33.3 16.521 2.5 35.2 16.519 2.498 37.3 16.513 2.492 39.5 16.511 2.49 41.8 16.506 2.485 44.3 16.502 2.481 46.9 16.496 2.475 49.7 16.493 2.472 52.6 16.487 2.466 55.7 16.482 2.461 59 16.476 2.455 62.5 16.471 2.45 66.2 16.463 2.442 70.1 16.456 2.435 74.3 16.452 2.431 78.7 16.445 2.424 83.4 16.435 2.414 88.4 16.428 2.407 93.7 16.421 2.4 99.3 16.413 2.392 105.2 16.402 2.381 111.5 16.393 2.372 118.1 16.382 2.361 125.1 16.371 2.35 132.6 16.361 2.34 140.5 16.348 2.327 148.9 16.337 2.316 157.8 16.324 2.303 167.2 16.311 2.29 177.2 16.3 2.279 187.8 16.28 2.259 B-17d Fall Data 199 16.263 2.242 210.9 16.245 2.224 223.5 16.223 2.202 236.8 16.206 2.185 250.9 16.186 2.165 265.8 16.165 2.144 281.6 16.143 2.122 298.4 16.125 2.104 316.2 16.11 2.089 335 16.097 2.076 354.9 16.082 2.061 376 16.065 2.044 398.4 16.045 2.024 422.1 16.021 2 447.2 15.989 1.968 473.8 15.96 1.939 502 15.926 1.905 531.9 15.893 1.872 563.5 15.858 1.837 597 15.821 1.8 632.5 15.784 1.763 670.1 15.743 1.722 709.9 15.704 1.683 752.1 15.66 1.639 796.8 15.619 1.598 844.2 15.571 1.55 894.4 15.53 1.509 947.5 15.48 1.459 1003.8 15.432 1.411 1063.4 15.382 1.361 1126.6 15.336 1.315 1193.5 15.284 1.263 1264.4 15.232 1.211 1339.5 15.18 1.159 1419 15.125 1.104 1503.3 15.071 1.05 1592.6 15.019 0.998 1687.1 14.96 0.939 1787.2 14.906 0.885 1893.3 14.851 0.83 2005.7 14.795 0.774 2124.7 14.741 0.72 2250.8 14.688 0.667 2384.4 14.634 0.613 2525.9 14.58 0.559 2675.8 14.529 0.508 2834.6 14.48 0.459 3002.8 14.432 0.411 3180.9 14.386 0.365 3369.6 14.343 0.322 3569.5 14.299 0.278 3781.2 14.26 0.239 4005.5 14.225 0.204 4243.1 14.188 0.167 4494.7 14.156 0.135 4761.3 14.127 0.106 5043.7 14.099 0.078 5342.8 14.077 0.056 5659.6 14.054 0.033 5995.2 14.036 0.015 6350.7 14.021 0 B-17d Fall Data Te r m U n i t s 2r c In c h e s 2. 0 6 7 2r W In c h e s 4 L w Fe e t 16 . 9 1 L e Fe e t 5 H* Fe e t 16 . 9 1 y 0 Fe e t 1. 3 t 0 Se c o n d s 0 y t Fe e t 0. 0 1 t Se c o n d s 2, 8 0 0 Te r m U n i t s 2.54E-04 In p u t D a t a 4.23E-06 Ca l c u l a t i o n s Solutions 3.281 Hy d r a u l i c C o n d u c t i v i t y i n F e e t / S e c o n d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / D a y 3.66E-01 * - A s s u m e d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / M i n u t e Wa t e r T a b l e Wa t e r T a b l e 2r c y L e /r W Fe e t / F o o t 3 0 . 0 0 A No n e 2 . 4 7 5 B N o n e 0 . 3 7 4 C N o n e 2 . 0 0 1 1 y 0 t y t Wh e r e 2r w K = A + B l n [ ( H - L W )/r W ] r c2 l n ( R e /r W ) 2L e ln Ge n e r a l E q u a t i o n s ln ( R e /r W )partial penetration = ln ( R e /r W )full penetration =3.281#NUM! S c r e e n L w L e H B o r e h o l e B o r e h o l e Fo r p a r t i a l p e n e t r a t i o n o r t h e e q u a t i o n b e l o w f o r f u l l p e n e t r a t i o n } -1 L e /r W 1. 1 ln ( L W /r W ) + ln ( R e / r W ) = { B- 1 7 d R e c o v e r y - S l u g T e s t C a l c u l a t i o n s Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Im p e r m e a b l e ln ( R e / r W ) = { 1. 1 + C L e /r W} -1 ln ( L W /r W ) A Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 110 Y 0 ( f e e t )A Ti m e ( s e c ) B-17d Recovery Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 0. 0 1 0. 1 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 4 0 0 0 4 5 0 0 5 0 0 0 B ‐17d  Recovery In-Situ Inc.MiniTroll Pro Report generated:1/26/2009 16:51:16 Report from file:...\SN04881 2009-01-23 170733 B-17d Slug Out.bin Win-Situ® Version 4.58.9.0 Serial number:4881 Firmware Version 3.09 Unit name: Test name:B-17d Slug Out Test defined on:1/23/2009 17:07:00 Test started on:1/23/2009 17:07:33 Test stopped on:N/A N/A Data gathered using Logarithmic testing Maximum time between data points: 4200.0Seconds. Number of data samples:137 TOTAL DATA SAMPLES 137 Channel number [1] Measurement type:Temperature Channel name:KS-6 weir Channel number [2] Measurement type:Pressure Channel name:KS-6 weir Sensor Range: 30 PSIG. Sensor Offset:0.000 psi Specific gravity:1 ET (sec)Feet H2O yt (feet) --------------------------- 0 10.495 0 0.3 11.97 1.644 0.6 12.829 0.785 0.9 12.708 0.906 1.2 12.44 1.174 1.5 12.364 1.25 1.8 12.416 1.198 2.1 12.465 1.149 2.4 12.469 1.145 2.7 12.46 1.154 3 12.462 1.152 3.3 12.465 1.149 3.6 12.464 1.15 3.9 12.465 1.149 4.2 12.473 1.141 4.5 12.475 1.139 4.8 12.476 1.138 5.1 12.48 1.134 5.4 12.478 1.136 B-17d Recovery Data 5.7 12.48 1.134 6 12.48 1.134 6.4 12.48 1.134 6.7 12.48 1.134 7.1 12.482 1.132 7.5 12.486 1.128 8 12.487 1.127 8.4 12.486 1.128 8.9 12.487 1.127 9.5 12.491 1.123 10 12.488 1.126 10.6 12.486 1.128 11.3 12.488 1.126 11.9 12.488 1.126 12.6 12.49 1.124 13.4 12.49 1.124 14.2 12.475 1.139 15 12.479 1.135 15.9 12.471 1.143 16.8 12.49 1.124 17.8 12.488 1.126 18.9 12.488 1.126 20 12.49 1.124 21.2 12.492 1.122 22.4 12.492 1.122 23.8 12.492 1.122 25.2 12.494 1.12 26.7 12.495 1.119 28.2 12.495 1.119 29.8 12.495 1.119 31.5 12.497 1.117 33.3 12.497 1.117 35.2 12.499 1.115 37.3 12.501 1.113 39.5 12.503 1.111 41.8 12.505 1.109 44.3 12.505 1.109 46.9 12.507 1.107 49.7 12.508 1.106 52.6 12.512 1.102 55.7 12.512 1.102 59 12.514 1.1 62.5 12.514 1.1 66.2 12.518 1.096 70.1 12.52 1.094 74.3 12.523 1.091 78.7 12.523 1.091 83.4 12.525 1.089 88.4 12.529 1.085 93.7 12.531 1.083 99.3 12.535 1.079 105.2 12.536 1.078 111.5 12.54 1.074 118.1 12.542 1.072 125.1 12.546 1.068 132.6 12.549 1.065 140.5 12.553 1.061 148.9 12.559 1.055 157.8 12.563 1.051 167.2 12.566 1.048 177.2 12.572 1.042 B-17d Recovery Data 187.8 12.575 1.039 199 12.581 1.033 210.9 12.587 1.027 223.5 12.592 1.022 236.8 12.598 1.016 250.9 12.603 1.011 265.8 12.609 1.005 281.6 12.616 0.998 298.4 12.624 0.99 316.2 12.631 0.983 335 12.638 0.976 354.9 12.648 0.966 376 12.655 0.959 398.4 12.664 0.95 422.1 12.674 0.94 447.2 12.685 0.929 473.8 12.694 0.92 502 12.705 0.909 531.9 12.718 0.896 563.5 12.729 0.885 597 12.74 0.874 632.5 12.755 0.859 670.1 12.77 0.844 709.9 12.783 0.831 752.1 12.798 0.816 796.8 12.814 0.8 844.2 12.831 0.783 894.4 12.848 0.766 947.5 12.866 0.748 1003.8 12.885 0.729 1063.4 12.903 0.711 1126.6 12.923 0.691 1193.5 12.946 0.668 1264.4 12.968 0.646 1339.5 12.988 0.626 1419 13.012 0.602 1503.3 13.036 0.578 1592.6 13.06 0.554 1687.1 13.086 0.528 1787.2 13.114 0.5 1893.3 13.14 0.474 2005.7 13.17 0.444 2124.7 13.197 0.417 2250.8 13.227 0.387 2384.4 13.259 0.355 2525.9 13.286 0.328 2675.8 13.32 0.294 2834.6 13.349 0.265 3002.8 13.381 0.233 3180.9 13.414 0.2 3369.6 13.445 0.169 3569.5 13.479 0.135 3781.2 13.507 0.107 4005.5 13.534 0.08 4243.1 13.562 0.052 4494.7 13.588 0.026 4761.3 13.614 0 B-17d Recovery Data Te r m U n i t s 2r c In c h e s 2. 0 6 7 2r W In c h e s 8 L w Fe e t 9 L e Fe e t 10 H* Fe e t 20 y 0 Fe e t 0. 3 1 t 0 Se c o n d s 0 y t Fe e t 0. 1 t Se c o n d s 70 0 Te r m U n i t s Wa t e r T a b l e Wa t e r T a b l e 2r c y In p u t D a t a 1.30E-06 Ca l c u l a t i o n s Solutions 2.175 Hy d r a u l i c C o n d u c t i v i t y i n F e e t / S e c o n d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / D a y 1.13E-01 * - A s s u m e d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / M i n u t e 7.82E-05 L e /r W Fe e t / F o o t 3 0 . 0 0 A No n e 2 . 4 7 5 B N o n e 0 . 3 7 4 C N o n e 2 . 0 0 1 1 y 0 t y t Wh e r e 2r w CD - 4 R e p F a l l - S l u g T e s t C a l c u l a t i o n s Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Im p e r m e a b l e ln ( R e / r W ) = { 1. 1 + C L e /r W} -1 ln ( L W /r W ) A Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n Fo r p a r t i a l p e n e t r a t i o n o r t h e e q u a t i o n b e l o w f o r f u l l p e n e t r a t i o n } -1 L e /r W 1. 1 ln ( L W /r W ) + ln ( R e / r W ) = { S c r e e n L w L e H B o r e h o l e B o r e h o l e ln Ge n e r a l E q u a t i o n s ln ( R e /r W )partial penetration = ln ( R e /r W )full penetration =2.4972.175 K = A + B l n [ ( H - L W )/r W ] r c2 l n ( R e /r W ) 2L e 10 Y 0 ( f e e t )A Ti m e ( s e c ) CD-4 Rep Fall Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 0. 1 1 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 4 0 0 0 CD ‐4  Rep  Fall In-Situ Inc.MiniTroll Pro Report generated:1/27/2009 11:04:17 Report from file:...\SN07563 2009-01-23 144556 CD-4 Rep.bin Win-Situ® Version 4.57.0.0 Serial number:7563 Firmware Version 3.09 Unit name: Test name:CD-4 Rep Test defined on:1/23/2009 14:44:57 Test started on:1/23/2009 14:45:56 Test stopped on:1/23/2009 15:49:16 Data gathered using Logarithmic testing Maximum time between data points: 4200.0Seconds. Number of data samples:133 TOTAL DATA SAMPLES 133 Channel number [1] Measurement type:Temperature Channel name: Channel number [2] Measurement type:Pressure Channel name:depth Sensor Range: 30 PSIG. Sensor Offset:0.000 psi Specific gravity:1 Mode:TOC User-defined reference:0 Feet H2O Referenced on:test start Pressure head at reference:8.47 Feet H2O ET (sec)Feet H2O yt (feet) --------------------------- 000 0.3 -0.898 0.898 0.6 -2.43 2.43 0.9 -1.596 1.596 1.2 -0.52 0.52 1.5 -0.763 0.763 1.8 -1.756 1.756 2.1 -1.212 1.212 2.4 -0.242 0.242 2.7 -0.455 0.455 3 -0.944 0.944 3.3 -0.59 0.59 3.6 -0.231 0.231 3.9 -0.431 0.431 4.2 -0.566 0.566 4.5 -0.362 0.362 4.8 -0.286 0.286 5.1 -0.391 0.391 5.4 -0.396 0.396 5.7 -0.317 0.317 CD-4 Rep Fall Data 6 -0.32 0.32 6.4 -0.355 0.355 6.7 -0.324 0.324 7.1 -0.32 0.32 7.5 -0.33 0.33 8 -0.317 0.317 8.4 -0.322 0.322 8.9 -0.317 0.317 9.5 -0.317 0.317 10 -0.307 0.307 10.6 -0.307 0.307 11.3 -0.305 0.305 11.9 -0.303 0.303 12.6 -0.303 0.303 13.4 -0.301 0.301 14.2 -0.299 0.299 15 -0.299 0.299 15.9 -0.297 0.297 16.8 -0.297 0.297 17.8 -0.297 0.297 18.9 -0.295 0.295 20 -0.295 0.295 21.2 -0.293 0.293 22.4 -0.293 0.293 23.8 -0.293 0.293 25.2 -0.293 0.293 26.7 -0.291 0.291 28.2 -0.291 0.291 29.8 -0.291 0.291 31.5 -0.291 0.291 33.3 -0.288 0.288 35.2 -0.288 0.288 37.3 -0.288 0.288 39.5 -0.288 0.288 41.8 -0.288 0.288 44.3 -0.286 0.286 46.9 -0.286 0.286 49.7 -0.287 0.287 52.6 -0.287 0.287 55.7 -0.287 0.287 59 -0.287 0.287 62.5 -0.287 0.287 66.2 -0.283 0.283 70.1 -0.285 0.285 74.3 -0.283 0.283 78.7 -0.283 0.283 83.4 -0.283 0.283 88.4 -0.281 0.281 93.7 -0.281 0.281 99.3 -0.281 0.281 105.2 -0.281 0.281 111.5 -0.281 0.281 118.1 -0.281 0.281 125.1 -0.281 0.281 132.6 -0.279 0.279 140.5 -0.279 0.279 148.9 -0.28 0.28 157.8 -0.277 0.277 167.2 -0.28 0.28 177.2 -0.277 0.277 187.8 -0.278 0.278 CD-4 Rep Fall Data 199 -0.278 0.278 210.9 -0.278 0.278 223.5 -0.276 0.276 236.8 -0.276 0.276 250.9 -0.276 0.276 265.8 -0.274 0.274 281.6 -0.276 0.276 298.4 -0.274 0.274 316.2 -0.276 0.276 335 -0.274 0.274 354.9 -0.274 0.274 376 -0.274 0.274 398.4 -0.274 0.274 422.1 -0.274 0.274 447.2 -0.274 0.274 473.8 -0.274 0.274 502 -0.277 0.277 531.9 -0.277 0.277 563.5 -0.274 0.274 597 -0.274 0.274 632.5 -0.277 0.277 670.1 -0.277 0.277 709.9 -0.281 0.281 752.1 -0.28 0.28 796.8 -0.28 0.28 844.2 -0.282 0.282 894.4 -0.28 0.28 947.5 -0.282 0.282 1003.8 -0.282 0.282 1063.4 -0.284 0.284 1126.6 -0.284 0.284 1193.5 -0.286 0.286 1264.4 -0.286 0.286 1339.5 -0.288 0.288 1419 -0.288 0.288 1503.3 -0.29 0.29 1592.6 -0.292 0.292 1687.1 -0.292 0.292 1787.2 -0.294 0.294 1893.3 -0.294 0.294 2005.7 -0.296 0.296 2124.7 -0.296 0.296 2250.8 -0.298 0.298 2384.4 -0.298 0.298 2525.9 -0.3 0.3 2675.8 -0.302 0.302 2834.6 -0.302 0.302 3002.8 -0.302 0.302 3180.9 -0.302 0.302 3369.6 -0.304 0.304 3569.5 -0.306 0.306 3781.2 -0.308 0.308 CD-4 Rep Fall Data Te r m U n i t s 2r c In c h e s 2. 0 6 7 2r W In c h e s 8 L w Fe e t 9 L e Fe e t 10 H* Fe e t 20 y 0 Fe e t 0. 2 t 0 Se c o n d s 0 y t Fe e t 0. 0 0 1 t Se c o n d s 3, 8 2 0 Te r m U n i t s Wa t e r T a b l e Wa t e r T a b l e 2r c y In p u t D a t a 1.12E-06 Ca l c u l a t i o n s Solutions 2.175 Hy d r a u l i c C o n d u c t i v i t y i n F e e t / S e c o n d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / D a y 9.66E-02 * - A s s u m e d Hy d r a u l i c C o n d u c t i v i t y i n F e e t / M i n u t e 6.71E-05 L e /r W Fe e t / F o o t 3 0 . 0 0 A No n e 2 . 4 7 5 B N o n e 0 . 3 7 4 C N o n e 2 . 0 0 1 1 y 0 t y t Wh e r e 2r w CD - 4 R e p R e c o v e r y - S l u g T e s t C a l c u l a t i o n s Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Im p e r m e a b l e ln ( R e / r W ) = { 1. 1 + C L e /r W} -1 ln ( L W /r W ) A Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n Fo r p a r t i a l p e n e t r a t i o n o r t h e e q u a t i o n b e l o w f o r f u l l p e n e t r a t i o n } -1 L e /r W 1. 1 ln ( L W /r W ) + ln ( R e / r W ) = { S c r e e n L w L e H B o r e h o l e B o r e h o l e ln Ge n e r a l E q u a t i o n s ln ( R e /r W )partial penetration = ln ( R e /r W )full penetration =2.4972.175 K = A + B l n [ ( H - L W )/r W ] r c2 l n ( R e /r W ) 2L e 110 Y 0 ( f e e t )A Ti m e ( s e c ) CD-4 REP Recovery Ca b a r r u s C o u n t y C & D L a n d f i l l E x p a n s i o n Si t e H y d r o g e o l o g i c I n v e s t i g a t i o n 0. 0 0 1 0. 0 1 0. 1 0 1 0 0 0 2 0 0 0 3 0 0 0 4 0 0 0 5 0 0 0 6 0 0 0 7 0 0 0 8 0 0 0 CD ‐4  Rep  Recovery In-Situ Inc.MiniTroll Pro Report generated:1/26/2009 16:52:00 Report from file:...\SN07563 2009-01-23 155106 CD-4 Rep Out.bin Win-Situ® Version 4.58.9.0 Serial number:7563 Firmware Version 3.09 Unit name: Test name:CD-4 Rep Out Test defined on:1/23/2009 15:50:01 Test started on:1/23/2009 15:51:06 Test stopped on:N/A N/A Data gathered using Logarithmic testing Maximum time between data points: 4200.0Seconds. Number of data samples:143 TOTAL DATA SAMPLES 143 Channel number [1] Measurement type:Temperature Channel name: Channel number [2] Measurement type:Pressure Channel name:depth Sensor Range: 30 PSIG. Sensor Offset:0.000 psi Specific gravity:1 Mode:TOC User-defined reference:0 Feet H2O Referenced on:test start Pressure head at reference:8.913 Feet H2O ET (sec)Feet H2O yt (feet) --------------------------- 000 0.3 2.469 2.142 0.6 1.509 1.182 0.9 0.809 0.482 1.2 2.106 1.779 1.5 0.823 0.496 1.8 1.412 1.085 2.1 1.423 1.096 2.4 0.857 0.53 2.7 1.383 1.056 3 1.014 0.687 3.3 0.978 0.651 3.6 1.149 0.822 3.9 0.857 0.53 4.2 0.971 0.644 4.5 0.935 0.608 4.8 0.796 0.469 5.1 0.858 0.531 5.4 0.778 0.451 5.7 0.756 0.429 CD-4 Rep Recovery Data 6 0.78 0.453 6.4 0.706 0.379 6.7 0.721 0.394 7.1 0.67 0.343 7.5 0.64 0.313 8 0.647 0.32 8.4 0.642 0.315 8.9 0.626 0.299 9.5 0.615 0.288 10 0.611 0.284 10.6 0.602 0.275 11.3 0.594 0.267 11.9 0.587 0.26 12.6 0.581 0.254 13.4 0.579 0.252 14.2 0.573 0.246 15 0.566 0.239 15.9 0.564 0.237 16.8 0.558 0.231 17.8 0.555 0.228 18.9 0.551 0.224 20 0.549 0.222 21.2 0.545 0.218 22.4 0.543 0.216 23.8 0.536 0.209 25.2 0.536 0.209 26.7 0.532 0.205 28.2 0.532 0.205 29.8 0.53 0.203 31.5 0.528 0.201 33.3 0.526 0.199 35.2 0.526 0.199 37.3 0.522 0.195 39.5 0.52 0.193 41.8 0.52 0.193 44.3 0.517 0.19 46.9 0.513 0.186 49.7 0.515 0.188 52.6 0.513 0.186 55.7 0.511 0.184 59 0.511 0.184 62.5 0.511 0.184 66.2 0.509 0.182 70.1 0.509 0.182 74.3 0.507 0.18 78.7 0.505 0.178 83.4 0.507 0.18 88.4 0.505 0.178 93.7 0.504 0.177 99.3 0.502 0.175 105.2 0.5 0.173 111.5 0.5 0.173 118.1 0.502 0.175 125.1 0.5 0.173 132.6 0.5 0.173 140.5 0.498 0.171 148.9 0.497 0.17 157.8 0.497 0.17 167.2 0.497 0.17 177.2 0.495 0.168 187.8 0.493 0.166 CD-4 Rep Recovery Data 199 0.495 0.168 210.9 0.493 0.166 223.5 0.493 0.166 236.8 0.491 0.164 250.9 0.491 0.164 265.8 0.49 0.163 281.6 0.488 0.161 298.4 0.488 0.161 316.2 0.486 0.159 335 0.486 0.159 354.9 0.484 0.157 376 0.484 0.157 398.4 0.482 0.155 422.1 0.482 0.155 447.2 0.48 0.153 473.8 0.48 0.153 502 0.48 0.153 531.9 0.475 0.148 563.5 0.476 0.149 597 0.474 0.147 632.5 0.474 0.147 670.1 0.471 0.144 709.9 0.47 0.143 752.1 0.468 0.141 796.8 0.466 0.139 844.2 0.464 0.137 894.4 0.459 0.132 947.5 0.458 0.131 1003.8 0.457 0.13 1063.4 0.455 0.128 1126.6 0.453 0.126 1193.5 0.451 0.124 1264.4 0.449 0.122 1339.5 0.446 0.119 1419 0.444 0.117 1503.3 0.442 0.115 1592.6 0.44 0.113 1687.1 0.438 0.111 1787.2 0.434 0.107 1893.3 0.432 0.105 2005.7 0.427 0.1 2124.7 0.425 0.098 2250.8 0.421 0.094 2384.4 0.419 0.092 2525.9 0.415 0.088 2675.8 0.41 0.083 2834.6 0.408 0.081 3002.8 0.404 0.077 3180.9 0.398 0.071 3369.6 0.396 0.069 3569.5 0.389 0.062 3781.2 0.386 0.059 4005.5 0.381 0.054 4243.1 0.377 0.05 4494.7 0.373 0.046 4761.3 0.364 0.037 5043.7 0.36 0.033 5342.8 0.352 0.025 5659.6 0.346 0.019 5995.2 0.335 0.008 6350.7 0.333 0.006 CD-4 Rep Recovery Data 6727.2 0.327 0 CD-4 Rep Recovery Data