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!!!!! !!!!! ! !!!!!! ! !!!!!!!!!!! !!!!!!!!!!!!!!!!!!! North Carolina Ground Water Resources Monitoring Well Network 2012$Annual$Report! Susan Laughinghouse, L.G. North Carolina Department of Environment and Natural Resources Division of Water Resources September 2012 ! Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 1 1.0 Introduction The State of North Carolina (the State) relies on ground water for approximately 50 percent of its drinking (potable) water use. In addition, the State has thousands of agricultural and industrial ground water users. Since 1998, the North Carolina Department of Environment and Natural Resources (DENR), Division of Water Resources (DWR) has monitored and maintained a statewide network of monitoring wells to assess North Carolina’s ground water supply. The operation of this monitoring well network is an essential part of DWR’s mission to ensure that the State has an adequate water supply for its citizens. Information (data) collected quarterly from this well network include the following: • Evaluating climatic influences on the State’s ground water supply, including effects of drought and recharge-discharge relationships; • Monitoring human-induced effects on the State’s ground water supply, particularly in the regional aquifer systems of the Coastal Plain physiographic province. These effects include local and regional water level declines as well as migration of the fresh water-salt water interface within various aquifers; • Providing supporting data for enforcement and creation of current and future ground water usage regulations, such as the Central Coastal Plain Capacity Use Area rules; and • Providing high quality ground water data to local governments, ground water professionals, and the general public to use in making informed decisions in ground water related issues. Data collected from the network are available to the public through DWR’s Internet website, www.ncwater.org. These data include ground water levels, chloride measurements, well construction information, borehole log construction (lithological and geophysical), ground water monitoring station locations, and geophysical/lithological data collection from non-DWR well sites. 2.0 Purpose and Scope The 2012 Annual Report summarizes field activities and conclusions derived from activities performed during the July 1, 2011 through June 30, 2012 fiscal year. These activities include water level and water quality data statistics, monitoring well installations including new installations, monitoring equipment usage and evaluations, and site surveys. 3.0 Background The Division of Water Quality (DWQ) and its predecessor agencies initially operated the statewide Ground Water Resource Monitoring Program. DWQ installed the original network wells in the 1960s and is responsible for installation of approximately 66 per cent of the current monitoring well network. DWQ actively monitored the network through the early 1990s, collecting a portion of the ground water data currently contained within the network database. The program was transferred to DWR in 1998. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 2 The U.S. Geological Survey (USGS) has also contributed to the monitoring of the State’s ground water resources under a cooperative agreement between the State of North Carolina and the Federal government. The cooperative well network consists of 13 monitoring wells, many of which are also part of the DWR statewide network. 4.0 DWR Statewide Monitoring Well Network Overview 4.1 Description The monitoring well network currently consists of 596 wells at 198 monitoring stations (sites), divided into five regions, comprising 61 counties (Figure 1). There are 28 wells located in the Piedmont and Mountain physiographic provinces (Piedmont and Mountain) and 568 wells located in the Coastal Plain physiographic province (Coastal Plain). The Coastal Plain relies more heavily on ground water supplies than either the Piedmont or Mountains. Subsequently, ground water monitoring and research has been more concentrated in the Coastal Plain. In the past few years, more resources have been invested in monitoring the Piedmont and Mountain ground water conditions to better understand the impact of drought cycles on ground water supplies and their contribution to surface water flow. There are 30 wells within the monitoring well network used to assess drought conditions (Figure 2). Of the 198 monitoring stations, 61 are on State or Federal property, 51 are located on property owned by local governments, 84 are located on private property through agreements with landowners and 2 stations are located on properties where landowner indicates that the land property ownership may change. In the past, some wells have been abandoned at the landowner’s request due to changes in land use or ownership. Due to the high cost of well construction combined with the fact that the wells are most valuable when they are monitored continuously over a period of decades, every attempt is made to put new stations in secure, stable locations. A scale has been developed to rank new and existing well sites for potential well abandonment due to land-use issues in the future (Table 1). It is preferred that new wells be installed at sites with a susceptibility rating of 1 or 2. Laurel Springs Station, Alleghany County Wilkesboro Station, Wilkes County North Pitt High School Station, Pitt County Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 3 4.2 Monitoring The statewide monitoring network is divided into five regions (Figure 1). One staff member is responsible for each region. Staff member responsibilities include visiting the wells quarterly to collect water level data, performing routine site maintenance, keeping automatic data recorders in working order and keeping sites accessible and esthetically pleasing. Additional site activities (i.e. recorder removal/replacement, weed/grass maintenance, video-logging, etc.) are conducted on an as needed basis. Video-Logging at Hope Plantation, Bertie County Depth to ground water level measurements are collected from the network in two different ways. Manual water levels are measured using electronic water level indicators. Hourly water level measurements are collected using one of two types of automatic water level recorders (shaft encoders or submersible pressure transducers, vented and unvented). Hourly water level data are extremely valuable in assessing aquifer recharge, impacts of large storms on ground water conditions, and delineation of aquifer boundaries. DWR typically publishes only the manual water level readings and daily water level data from recorders on the website. However, hourly data is available upon request for specific wells. Table 2 summarizes site and recorder distribution by region. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 4 Triennial chloride samples are collected from select wells in the Coastal Plain. The samples are analyzed using the Quantab field method. Field results are used to monitor the migration of the fresh water-salt water interface in the Coastal Plain aquifers. Additional chloride samples are collected for field analyses when new monitoring wells are installed and as needed for special projects. The next chloride sampling event will occur September 2013. In addition, a special chloride sampling is being conducted in September 2012. Section 5.2 summarizes the 2010 chloride sampling event. 5.0 2011-2012 Well Network Statistics 5.1 Ground Water Data Collection Depth to ground water was measured in 594 wells in the July 1, 2011 through June 30, 2012 fiscal year. The following wells were not measured for four consecutive quarters during the 2011/2012 fiscal year: • P17E4, Whitley Farms, was dry for two consecutive quarters (August and November 2011), therefore, depth to ground water could not be measured in this well. The well was placed on the inactive list and abandoned in the spring of 2012. • O10W1, Hydeland, was interpreted to be a hybrid well and placed on the inactive well list in 2010. However, water levels were collected from this well in February, May, and August of 2011. Monitoring well O10W1 is scheduled for replacement. • O17I3, Bath, was interpreted to be a hybrid well and placed on the inactive list. Water levels were collected from this well in May and August of 2012. • V26W1, Robert Black Residence, was placed on the inactive list in December 2011. Water levels were collected from well O17I3 in August and November of 2011. Manual water level collection. Electronic water level recorder (Hobo connected to Shuttle) Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 5 • CC30P2, Wilmington Airport, was damaged in the fall of 2011. Partial electronic data was collected during the 2011/2012 fiscal year, however, DWR personnel were unable to collect manual water levels. This well was abandoned in January 2012. Table 3 contains DWR monitoring well network statistics from January 1, 2005 through June 30, 2012. Statistics may vary in comparison to previous years due to additional data entry in the DWR database as older field books are scanned and unrecorded data entered. Figure 3 compares the number of wells monitored to the water level data collected from the network from 1967 to present. Hourly water level data is not included in this graph. Calendar year 2011 represents the most water level data collected in any single year since starting the monitoring well network operation. This is due to the gradual increase in the number of wells monitored and the increased use of automatic data recorders. The 2012 data was collected through June 2012. Archived water level recorder charts obtained from DWQ with records dating from the 1960s through 1980s continue to be digitized and data recorded into DWR online database. Additional continued digitized information recorded in the database includes, but is not limited to, well construction records, well development, chloride sampling events, memorandums of agreement, and field notes. 5.2 Triennial Chloride Sampling The triennial chloride sampling was performed in September and October 2010. Ground water from 245 wells within the network was sampled for chlorides using Quantab® chloride titrators. Field data were collected for pH, conductivity, and salinity using YSI® portable probes. Chloride Sampling Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 6 The intention of the triennial chloride sampling is to assess the position of the fresh water-salt water interface within each of the major coastal plain aquifers. Current results are compared to results of previous sampling events to evaluate potential landward migration of the fresh water-salt water interface due to aquifer overuse. Chloride sampling results are posted in the database and the DWR website. Sampling results indicate that there continues to be concern for salt-water encroachment, especially near larger pumping centers located near the fresh water-salt water interface (250 parts per million (ppm) chloride is considered salt water). The September 2010 chloride field sampling results associated with wells near larger pumping centers illustrate these type of issues: • Chloride concentrations from October 2010 in the lower Castle Hayne aquifer well Q16G4 at the Godley Station continue to indicate salt water intrusion with levels of 531 ppm which exceed the 250 ppm threshold for salt water. This station is located near PCS Phosphate Inc. at Aurora, NC in Beaufort County. • Chloride concentrations from the Peedee aquifer well Y25Q4 at the Folkstone Station show a large decrease in chlorides from 252 ppm on September 2007 to BDL (below detection limit of 33 ppm) in September 25, 2010. This station is located near the ONWASA Dixon well field in Onslow County. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 7 • Chloride concentrations from the Upper Cape Fear aquifer well J22P5 at the Gold Point Station decreased from 162 ppm in September 2007 to 54 ppm in September 2010. This station is located near the town of Robersonville in Martin County. • Chloride concentrations from the Upper Cape Fear aquifer well R23X9 at the Cove City station increased from 352 ppm in October 2007 to 463 ppm in September 2010. This well is located near the town of Cove City, North Carolina. Table 4 summarizes the chloride field analysis to date. Chloride sampling will take place again in September and October 2012. 5.3 Well Installation From March through May 2012, the following monitoring wells were installed: • Ivanhoe Station, Ivanhoe, Duplin County, one well, Y34P7; • Camp Glenn Station in Morehead City, Carteret County, one well, X17J7; • Whitley Farms in Beaufort County, one well, P17E5; and • Farmville Marlboro Rd. Station in Farmville, Pitt County, five wells, M27U13, M27U14, M27U15, M27U16 and M27U17. The wells were installed using 4-inch PVC riser and 10 or 20 feet of 4 to 4.5-inch stainless steel continuous wire wrap V-slot screen (wells greater than 70 feet) or 4 inch .020 slot PVC screen (wells less than 70 feet). The wells were constructed of a gravel pack extending from the bottom of the screen to a minimum of five feet, but no more than ten feet, above the screen. A minimum of ten feet of bentonite overlay the top of the gravel pack in order to provide a sufficient bentonite seal in the well. Table 5 summarizes the monitoring well construction information. Slotted Screen with Tail Pipe Gravel Pack Installation Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 8 A pilot hole was not advanced prior to installing the wells at the Ivanhoe, Camp Glenn, and Whitley Farms stations since these stations had pilot holes advanced in previous years and geophysical logging was conducted. Pilot holes were advanced and geophysical logging conducted at the Farmville Marlboro Rd. station prior to well installation. Geophysical and lithologic log interpretation enabled the DWR staff to assess well screen intervals and the number of wells to be installed. Borehole advancement and well installation included well development and chloride measurement collection. Monitoring wells at Ivanhoe (Y34P7), Camp Glenn (X17J7), and Whitley Farms (P17E5), were developed from March through June 2012 by pumping. Development removes fine-grained sediments from the vicinity of the well screen and ensures proper hydraulic connection with the aquifer. In addition, field data were collected for pH, conductivity, salinity, and temperature in thirty minute or hourly intervals. Field data exhibiting overall consistency was used to assist in the decision to stop well development. Pressure grouting using bentonite grout Samples for lithologic interpretation Geophysical Logger Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 9 5.4 Well Maintenance The well network requires continual maintenance to keep active monitoring stations usable. Many of the wells exceed 30 years in age and are constructed of materials that are susceptible to corrosion, especially in acidic or saline ground water conditions. Some older wells were constructed with outdated, less than desirable construction practices including backfilling boreholes with cuttings instead of neat cement or bentonite grout. Boreholes backfilled with cuttings form an inadequate seal and allow other aquifers to influence the water level and water quality in that well. Another outdated practice included well construction using telescoped casing. Telescoped casing uses a reducer to trim the well to a smaller diameter casing at depth apparently to save money during well construction. Telescoped wells are very susceptible to blockage at the depth of the reducer. Approximately 152 wells in the network were constructed with reducers. DWR has implemented a long-term program for replacing damaged or unsuitably constructed wells with new properly constructed wells. In addition to replacing monitoring wells, DWR was able to repair wells in order to make them usable. The following wells were repaired between February and June 2012: • Winsteadville Station, Beaufort County, O15N5, replaced outer casing & shale trap; • Clark’s Station, Craven County, S22J5, replaced/repaired shale trap; • Arapahoe Station, Pamlico County, S18U10, removed bent casing and replaced with new casing and; • Cox Crossroads Station, Beaufort County, P19M4, installed shale trap and installed protective sleeve on outer casing. The shale trap is a bell shaped piece of rubber which is clamped to the PVC casing and placed below the damaged area of the well. The inside of the shale trap is grouted from where it is attached to the casing to the surface, in order to seal the damaged area of the well and maintain the well’s integrity. Well Development Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 10 Installation of new and replacement monitoring wells occupies a large portion of DWR’s resources. Table 5 lists the new wells installed during the 2011-2012 fiscal year. The new wells are included on Figure 1. 5.5 Automatic Water Level Recorders Automatic water level recorders play an integral role in the DWR monitoring program. They allow for economical collection of near-continuous data at remote well stations. Four primary recorders are utilized and are included Table 6. Hobo including barometer, shuttle and water level indicator Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 11 Sutron including card reader, 12-volt battery and voltage meter Global Water WL16 including iPAQ, field book and calculator Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 12 5.6 Site Surveys Concrete survey monuments continue to be installed at each of the 198 monitoring well stations within the network. Once installation is complete, the monuments will be surveyed using Survey Grade Global Positioning System (GPS) to calculate the most accurate horizontal and vertical location data possible. At the end of the fiscal year, 190 monuments had been installed. It is anticipated that this work will be completed by the end of the year 2012. Surveying of the monuments will take place once monument installation at each well station is complete. 6.0 Planned Activities for FY 2012-2013 6.1 New Well Installation Monitoring well network expansion efforts for FY 2012-2013 will be focused on Beaufort, Bladen, Chowan, Columbus, Duplin, New Hanover, Pender, Pitt, Sampson, Scotland, Washington, and Wayne Counties. In addition, some wells throughout the network that cannot be used due to bad construction, screening in multiple aquifers, etc., may be abandoned during this upcoming fiscal year. Table 7 summarizes the possible upcoming expansion of the network in 2012-2013. 6.2 Well Abandonment The following wells were abandoned during FY 2011-2012: Whitley Farms, Beaufort County, P17E4 and Wilmington Airport, New Hanover County, CC30P2. Gas auger and monument Top of monument - survey point Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 13 7.0 Summary and Conclusions The NCDENR, DWR has maintained and monitored a statewide network of ground water monitoring wells used to assess North Carolina’s ground water supply since 1998. Data collected from the network are available to the public through DWR’s Internet website, www.ncwater.org. These data include, but are not limited to, ground water levels, chloride measurements, well construction information, borehole log construction (lithological and geophysical), ground water monitoring station locations, and geophysical/lithological data collected from other (non-DWR) well sites. The well network consists of 596 monitoring wells at 198 individual stations. From July 2011 through June 2012, ground water level data were collected from 594 wells within the network. These data include manual measurements taken quarterly from wells, plus hourly water levels collected using automatic data recorders from 498 wells. A total of eight monitor wells have been installed at four different stations. One monitoring well was installed at Ivanhoe (Duplin County), one monitoring well was installed at Camp Glenn (Carteret County), one well was installed at Whitley Farms (Beaufort County), and five monitoring wells were installed at Farmville Marlboro Rd. (Pitt County). Borehole advancement and well installation included, but was not limited to, well development and collection of chloride measurements. A total of two wells were abandoned at two different stations: well P17E4 at Whitley Farms, Beaufort County and well CC30P2 at Wilmington Airport, New Hanover County. Archived water level recorder charts obtained from the DWQ with records dating from the 1960s through 1980s continue to be digitized and data recorded into the DWR online database. Survey monuments continue to be installed at each of the well stations with plans to survey each monument using Survey Grade GPS. The triennial chloride sampling was performed on 245 wells in September/October 2010. Thirteen additional samples were collected from the new well installations between in December and May 2011. One additional sample was collected from the new installation in April 2012. Sampling results indicated that there continues to be concern for saltwater encroachment especially near larger pumping centers located near the fresh-salt water interface. Chloride sampling will occur again in September 2012. DWR has tentative plans to expand the monitoring well network by installing thirteen to twenty-six wells at seven to ten sites in fiscal year 2012/2013. In addition several wells in the network may be scheduled for abandonment, replacement, and repair. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report FIGURES Legend New or Improved Monitoring Stations Active Monitoring Stations Regions 1 2 3 4 5 Fall Line 0 50 100 150 200 250 Miles Figure 1: North Carolina Division of Water Resources Monitoring Stations August 2011 NCDENR Division of Water Resources NC Ground Water Resources Monitoring Well Network 2012 Annual Report 0 20,000 40,000 60,000 80,000 100,000 120,000 140,000 160,000 0 100 200 300 400 500 600 700 Number of Daily Water Levels Collected Number of Network Wells Measured Year FIGURE 3 Water&Level&Data&Collected&from&196752012& (Plot&includes&both&DWR&and&USGS&Data)& No. of Wells No. Daily Water levels (includes both DWR and USGS wells) Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLES Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 1 Site Susceptibility Rating North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Susceptibility Rating Description 1 Secure—station is located on State or Federal government property 2 Secure—station is located on local government or school property 3 Moderately secure—station is located on private property, but landowner does not give any indication that land use or property ownership may change 4 Tenuous—station is located on public or private property and landowner is giving indications that land use or property ownership may change 5 Imminent threat—station is on public or private property and landowner desires abandonment of well station. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 2 Site and Recorder Distribution by Region through 6/30/12 North Carolina Division of Ground Water Resources Monitoring Well Network 2012 Annual Report Region Parameter Number % of Region % of Network Wells 122 20.5 Sites 41 20.7 Sutrons 0 0.0 0.0 1 WL15s 0 0.0 0.0 WL16s 50 41.0 8.4 Hobos 48 39.3 8.1 All Recorders 98 80.3 16.4 Wells 154 25.8 Sites 41 20.7 Sutrons 3 1.9 0.5 2 WL15s 19 12.3 3.2 WL16s 50 32.5 8.4 Hobos 55 35.7 9.2 All Recorders 127 82.5 21.3 Wells 112 18.8 Sites 26 13.1 Sutrons 3 2.7 0.5 3 WL15s 4 3.6 0.7 WL16s 42 37.5 7.0 Hobos 25 22.3 4.2 All Recorders 74 66.1 12.4 Wells 131 22.0 Sites 42 21.2 Sutrons 0 0.0 0.0 4 WL15s 9 6.9 1.5 WL16s 24 18.3 4.0 Hobos 46 35.1 7.7 All Recorders 79 60.3 13.3 Wells 77 12.9 Sites 46 23.2 Sutrons 6 7.8 1.0 5 WL15s 10 13.0 1.7 WL16s 16 20.8 2.7 Hobos 29 37.7 4.9 All Recorders 61 79.2 10.2 Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 18 TABLE 3 DWR Monitoring Well Network Statistics (1-1-05) through (6-30-12) North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Parameter 2005 2006 2007 2008 2009 2010 2011 2012 Number of monitored wells 542 544 555 565 575 579 591 594 Manual water levels (tapedowns) 2,633 2,738 2,618 2,468 2,556 2,911 2627 1394 Daily water levels (automatic recorders 89,088 92,827 95,333 107,883 122,969 131,325 136,209 61,746 Total hourly water levels 2,141,368 2,229,355 2,294,909 2,591,483 2,961,371 3,163,229 3,276,498 1,479,961 Chloride Samples 17 22 175 12 17 251 21 1 Geophysical & lithologic logs at new stations 2 1 3 1 1 0 2 1 Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 19 TABLE 4 Chloride Field Analysis to Date Wells Q16G4, Y25Q4, J22P5 and R23X9 Ground Water Resources Monitoring Well Network 2012 Annual Report Station Date Chlorides (ppm) 10/04/2010 531 10/01/2007 564 Godley 09/15/2004 137 Station 10/07/1999 91 Q16G4 07/14/1998 174 02/23/1981 No Reading Available 09/22/2010 BDL of 33 09/25/2007 252 Folkstone 09/14/2004 266 Station 10/12/1999 35 Y25Q4 08/06/1998 11 09/25/1982 No Reading Available 10/04/2010 54 Gold Point 09/24/2007 162 Station 09/30/2004 BDL of 28 ** J22P5 09/15/2004 BDL of 28 06/10/2002 10 09/20/2010 463 Cove City 10/05/2007 352 Station 09/13/2004 309 R23X9 10/04/2000 30 Chloride Level for Salt Water 250 **Collected after well development Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 20 TABLE 5 Well Construction Information Ivanhoe, Sampson County, Camp Glenn, Carteret County, Whitley Farms, Beaufort County and Farmville Marlboro Rd., Pitt North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Well ID Station Name Date Installed Well Diameter (inches) Well Depth (ft bls) Screened Interval (x to y ft bls) Measuring Pt. (MP) (ft) Aquifer Water Level (from MP) (ft) Measured - 6/26/12 Y34P7 Ivanhoe 04/13/12 4 135 110-130 2.92 Pee Dee 5.55 Measured – 5/23/12 X17J7 Camp Glenn 03/27/12 4 17 10-15 3.00 Surficial 7.36 Measured – 5/29/12 P17E5 Whitley Farms 04/19/12 4 35 20-30 2.79 Surficial 9.05 M27U13 Farmville Marlboro Rd. 05/15/12 4 329 314-324 2.98 To Be Determined Not Measured M27U14 Farmville Marlboro Rd. 05/29/12 4 245 230-240 2.82 To Be Determined Not Measured M27U15 Farmville Marlboro Rd. 06/06/12 4 145 130-140 2.96 To Be Determined Not Measured M27U16 Farmville Marlboro Rd. 05/07/12 4 55 40-50 3.13 To Be Determined Not Measured M27U17 Farmville Marlboro Rd. 05/03/12 4 30 15-25 2.96 Surficial Not Measured Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 21 TABLE 6 Automatic Water Level Recorders North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Recorder Type Number in Service* Sutron Corporation Model 8400A 12 Global Water Instrumentation, Inc. Model WL15 42 Global Water Instrumentation, Inc. Model WL16 182 HOBO U20 Water Level Logger (including separate barometer per station installed 262 (59 barometers) *As of June 30, 2012 Note: Due to the large number of recorders employed by DWR, there are, at any given time, a number of units that are being serviced or replaced. These units are not reflected in the above totals. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 FY 2012-2013 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 100-110 Yorktown Pocosin Lake Area Washington 200-210 Castle Hayne (upper) 350-360 Castle Hayne (lower saltwater) 500-510 Beaufort 600 Pilot Hole Ivanhoe Sampson 440-450 Upper Cape Fear 20-30 Surficial Vicinity of Walnut 45-55 Black Creek or Surficial Creek Wayne 100-110 Black Creek 220-230 Upper Cape Fear 350 Pilot Hole (Top of Basement) Burgaw Pender 20-30 Surficial 630-640 Upper Cape Fear Kelly Bladen 280-290 Surficial 448-458 Upper Cape Fear 20-30 Surficial 90-100 Castle Hayne North Central New Hanover County New Hanover 220-230 Upper Pee Dee 350-360 Lower Pee Dee 450 Pilot Hole Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 (continued) FY 2011-2012 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 30-40 Pee Dee Vicinity of Faison/Warsaw Northwestern Duplin County 140-150 Black Creek 265-275 Upper Cape Fear 400-410 Lower Cape Fear 448 Pilot Hole 20-30 Surficial 80-90 Yorktown Between DWR Godley and Aurora Beaufort 250-260 Castle Hayne (upper) 440-450 Castle Hayne (lower) 610-620 Beaufort 650-660 Pee Dee 700 Pilot Hole 20-30 Surficial Nakina Columbus 380-390 Black Creek 844-854 Lower Cape Fear 20-30 Surficial USGS Core Hole Site at Fort Fisher/Kure Beach New Hanover 95-105 Castle Hayne 160-170 Pee Dee Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 (continued) FY 2011-2012 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 110-120 Pee Dee Vicinity of Moore’s Creek National Park Pender County 330-340 Black Creek 590-600 Upper Cape Fear 630 Pilot Hole 20-30 Surficial Turkey Sampson 318-328 Upper Cape Fear 432-442 Lower Cape Fear 20-30 Surficial Vicinity of Salemburg Sampson 80-90 Black Creek 206-216 Upper Cape Fear 20-30 Surficial Town of Laurinburg Scotland 120-130 Black Creek 332-342 Upper Black Creek 20-30 Surficial 80-90 Yorktown Vicinity of Valhalla Chowan 220-230 Castle Hayne 320-330 Beaufort 450-460 Upper Cape Fear 850-860 Lower Cape Fear 1200-1210 Lower Cretaceous 1300 Pilot Hole Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 (continued) FY 2011-2012 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 124-134 Yorktown 244-254 Castle Hayne (upper) Belhaven Beaufort 312-322 Castle Hayne (lower) 388-398 Beaufort 540-550 Pee Dee 720-730 Black Creek 900 Pilot 20-30 Surficial 46-56 Yorktown River Park North Pitt 110-120 Pee Dee 150-160 Upper Black Creek 252-262 Lower Black Creek 380-390 Upper Cape Fear
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Title | North Carolina ground water resources monitoring well network... annual report |
Date | 2012-09 |
Description | 2012 |
Digital Characteristics-A | 15.5 MB; 29 p. |
Digital Format |
application/pdf |
Pres File Name-M | pubs_serial_ncgroundwaterresources2012.pdf |
Full Text | !!!!! !!!!! ! !!!!!! ! !!!!!!!!!!! !!!!!!!!!!!!!!!!!!! North Carolina Ground Water Resources Monitoring Well Network 2012$Annual$Report! Susan Laughinghouse, L.G. North Carolina Department of Environment and Natural Resources Division of Water Resources September 2012 ! Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 1 1.0 Introduction The State of North Carolina (the State) relies on ground water for approximately 50 percent of its drinking (potable) water use. In addition, the State has thousands of agricultural and industrial ground water users. Since 1998, the North Carolina Department of Environment and Natural Resources (DENR), Division of Water Resources (DWR) has monitored and maintained a statewide network of monitoring wells to assess North Carolina’s ground water supply. The operation of this monitoring well network is an essential part of DWR’s mission to ensure that the State has an adequate water supply for its citizens. Information (data) collected quarterly from this well network include the following: • Evaluating climatic influences on the State’s ground water supply, including effects of drought and recharge-discharge relationships; • Monitoring human-induced effects on the State’s ground water supply, particularly in the regional aquifer systems of the Coastal Plain physiographic province. These effects include local and regional water level declines as well as migration of the fresh water-salt water interface within various aquifers; • Providing supporting data for enforcement and creation of current and future ground water usage regulations, such as the Central Coastal Plain Capacity Use Area rules; and • Providing high quality ground water data to local governments, ground water professionals, and the general public to use in making informed decisions in ground water related issues. Data collected from the network are available to the public through DWR’s Internet website, www.ncwater.org. These data include ground water levels, chloride measurements, well construction information, borehole log construction (lithological and geophysical), ground water monitoring station locations, and geophysical/lithological data collection from non-DWR well sites. 2.0 Purpose and Scope The 2012 Annual Report summarizes field activities and conclusions derived from activities performed during the July 1, 2011 through June 30, 2012 fiscal year. These activities include water level and water quality data statistics, monitoring well installations including new installations, monitoring equipment usage and evaluations, and site surveys. 3.0 Background The Division of Water Quality (DWQ) and its predecessor agencies initially operated the statewide Ground Water Resource Monitoring Program. DWQ installed the original network wells in the 1960s and is responsible for installation of approximately 66 per cent of the current monitoring well network. DWQ actively monitored the network through the early 1990s, collecting a portion of the ground water data currently contained within the network database. The program was transferred to DWR in 1998. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 2 The U.S. Geological Survey (USGS) has also contributed to the monitoring of the State’s ground water resources under a cooperative agreement between the State of North Carolina and the Federal government. The cooperative well network consists of 13 monitoring wells, many of which are also part of the DWR statewide network. 4.0 DWR Statewide Monitoring Well Network Overview 4.1 Description The monitoring well network currently consists of 596 wells at 198 monitoring stations (sites), divided into five regions, comprising 61 counties (Figure 1). There are 28 wells located in the Piedmont and Mountain physiographic provinces (Piedmont and Mountain) and 568 wells located in the Coastal Plain physiographic province (Coastal Plain). The Coastal Plain relies more heavily on ground water supplies than either the Piedmont or Mountains. Subsequently, ground water monitoring and research has been more concentrated in the Coastal Plain. In the past few years, more resources have been invested in monitoring the Piedmont and Mountain ground water conditions to better understand the impact of drought cycles on ground water supplies and their contribution to surface water flow. There are 30 wells within the monitoring well network used to assess drought conditions (Figure 2). Of the 198 monitoring stations, 61 are on State or Federal property, 51 are located on property owned by local governments, 84 are located on private property through agreements with landowners and 2 stations are located on properties where landowner indicates that the land property ownership may change. In the past, some wells have been abandoned at the landowner’s request due to changes in land use or ownership. Due to the high cost of well construction combined with the fact that the wells are most valuable when they are monitored continuously over a period of decades, every attempt is made to put new stations in secure, stable locations. A scale has been developed to rank new and existing well sites for potential well abandonment due to land-use issues in the future (Table 1). It is preferred that new wells be installed at sites with a susceptibility rating of 1 or 2. Laurel Springs Station, Alleghany County Wilkesboro Station, Wilkes County North Pitt High School Station, Pitt County Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 3 4.2 Monitoring The statewide monitoring network is divided into five regions (Figure 1). One staff member is responsible for each region. Staff member responsibilities include visiting the wells quarterly to collect water level data, performing routine site maintenance, keeping automatic data recorders in working order and keeping sites accessible and esthetically pleasing. Additional site activities (i.e. recorder removal/replacement, weed/grass maintenance, video-logging, etc.) are conducted on an as needed basis. Video-Logging at Hope Plantation, Bertie County Depth to ground water level measurements are collected from the network in two different ways. Manual water levels are measured using electronic water level indicators. Hourly water level measurements are collected using one of two types of automatic water level recorders (shaft encoders or submersible pressure transducers, vented and unvented). Hourly water level data are extremely valuable in assessing aquifer recharge, impacts of large storms on ground water conditions, and delineation of aquifer boundaries. DWR typically publishes only the manual water level readings and daily water level data from recorders on the website. However, hourly data is available upon request for specific wells. Table 2 summarizes site and recorder distribution by region. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 4 Triennial chloride samples are collected from select wells in the Coastal Plain. The samples are analyzed using the Quantab field method. Field results are used to monitor the migration of the fresh water-salt water interface in the Coastal Plain aquifers. Additional chloride samples are collected for field analyses when new monitoring wells are installed and as needed for special projects. The next chloride sampling event will occur September 2013. In addition, a special chloride sampling is being conducted in September 2012. Section 5.2 summarizes the 2010 chloride sampling event. 5.0 2011-2012 Well Network Statistics 5.1 Ground Water Data Collection Depth to ground water was measured in 594 wells in the July 1, 2011 through June 30, 2012 fiscal year. The following wells were not measured for four consecutive quarters during the 2011/2012 fiscal year: • P17E4, Whitley Farms, was dry for two consecutive quarters (August and November 2011), therefore, depth to ground water could not be measured in this well. The well was placed on the inactive list and abandoned in the spring of 2012. • O10W1, Hydeland, was interpreted to be a hybrid well and placed on the inactive well list in 2010. However, water levels were collected from this well in February, May, and August of 2011. Monitoring well O10W1 is scheduled for replacement. • O17I3, Bath, was interpreted to be a hybrid well and placed on the inactive list. Water levels were collected from this well in May and August of 2012. • V26W1, Robert Black Residence, was placed on the inactive list in December 2011. Water levels were collected from well O17I3 in August and November of 2011. Manual water level collection. Electronic water level recorder (Hobo connected to Shuttle) Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 5 • CC30P2, Wilmington Airport, was damaged in the fall of 2011. Partial electronic data was collected during the 2011/2012 fiscal year, however, DWR personnel were unable to collect manual water levels. This well was abandoned in January 2012. Table 3 contains DWR monitoring well network statistics from January 1, 2005 through June 30, 2012. Statistics may vary in comparison to previous years due to additional data entry in the DWR database as older field books are scanned and unrecorded data entered. Figure 3 compares the number of wells monitored to the water level data collected from the network from 1967 to present. Hourly water level data is not included in this graph. Calendar year 2011 represents the most water level data collected in any single year since starting the monitoring well network operation. This is due to the gradual increase in the number of wells monitored and the increased use of automatic data recorders. The 2012 data was collected through June 2012. Archived water level recorder charts obtained from DWQ with records dating from the 1960s through 1980s continue to be digitized and data recorded into DWR online database. Additional continued digitized information recorded in the database includes, but is not limited to, well construction records, well development, chloride sampling events, memorandums of agreement, and field notes. 5.2 Triennial Chloride Sampling The triennial chloride sampling was performed in September and October 2010. Ground water from 245 wells within the network was sampled for chlorides using Quantab® chloride titrators. Field data were collected for pH, conductivity, and salinity using YSI® portable probes. Chloride Sampling Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 6 The intention of the triennial chloride sampling is to assess the position of the fresh water-salt water interface within each of the major coastal plain aquifers. Current results are compared to results of previous sampling events to evaluate potential landward migration of the fresh water-salt water interface due to aquifer overuse. Chloride sampling results are posted in the database and the DWR website. Sampling results indicate that there continues to be concern for salt-water encroachment, especially near larger pumping centers located near the fresh water-salt water interface (250 parts per million (ppm) chloride is considered salt water). The September 2010 chloride field sampling results associated with wells near larger pumping centers illustrate these type of issues: • Chloride concentrations from October 2010 in the lower Castle Hayne aquifer well Q16G4 at the Godley Station continue to indicate salt water intrusion with levels of 531 ppm which exceed the 250 ppm threshold for salt water. This station is located near PCS Phosphate Inc. at Aurora, NC in Beaufort County. • Chloride concentrations from the Peedee aquifer well Y25Q4 at the Folkstone Station show a large decrease in chlorides from 252 ppm on September 2007 to BDL (below detection limit of 33 ppm) in September 25, 2010. This station is located near the ONWASA Dixon well field in Onslow County. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 7 • Chloride concentrations from the Upper Cape Fear aquifer well J22P5 at the Gold Point Station decreased from 162 ppm in September 2007 to 54 ppm in September 2010. This station is located near the town of Robersonville in Martin County. • Chloride concentrations from the Upper Cape Fear aquifer well R23X9 at the Cove City station increased from 352 ppm in October 2007 to 463 ppm in September 2010. This well is located near the town of Cove City, North Carolina. Table 4 summarizes the chloride field analysis to date. Chloride sampling will take place again in September and October 2012. 5.3 Well Installation From March through May 2012, the following monitoring wells were installed: • Ivanhoe Station, Ivanhoe, Duplin County, one well, Y34P7; • Camp Glenn Station in Morehead City, Carteret County, one well, X17J7; • Whitley Farms in Beaufort County, one well, P17E5; and • Farmville Marlboro Rd. Station in Farmville, Pitt County, five wells, M27U13, M27U14, M27U15, M27U16 and M27U17. The wells were installed using 4-inch PVC riser and 10 or 20 feet of 4 to 4.5-inch stainless steel continuous wire wrap V-slot screen (wells greater than 70 feet) or 4 inch .020 slot PVC screen (wells less than 70 feet). The wells were constructed of a gravel pack extending from the bottom of the screen to a minimum of five feet, but no more than ten feet, above the screen. A minimum of ten feet of bentonite overlay the top of the gravel pack in order to provide a sufficient bentonite seal in the well. Table 5 summarizes the monitoring well construction information. Slotted Screen with Tail Pipe Gravel Pack Installation Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 8 A pilot hole was not advanced prior to installing the wells at the Ivanhoe, Camp Glenn, and Whitley Farms stations since these stations had pilot holes advanced in previous years and geophysical logging was conducted. Pilot holes were advanced and geophysical logging conducted at the Farmville Marlboro Rd. station prior to well installation. Geophysical and lithologic log interpretation enabled the DWR staff to assess well screen intervals and the number of wells to be installed. Borehole advancement and well installation included well development and chloride measurement collection. Monitoring wells at Ivanhoe (Y34P7), Camp Glenn (X17J7), and Whitley Farms (P17E5), were developed from March through June 2012 by pumping. Development removes fine-grained sediments from the vicinity of the well screen and ensures proper hydraulic connection with the aquifer. In addition, field data were collected for pH, conductivity, salinity, and temperature in thirty minute or hourly intervals. Field data exhibiting overall consistency was used to assist in the decision to stop well development. Pressure grouting using bentonite grout Samples for lithologic interpretation Geophysical Logger Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 9 5.4 Well Maintenance The well network requires continual maintenance to keep active monitoring stations usable. Many of the wells exceed 30 years in age and are constructed of materials that are susceptible to corrosion, especially in acidic or saline ground water conditions. Some older wells were constructed with outdated, less than desirable construction practices including backfilling boreholes with cuttings instead of neat cement or bentonite grout. Boreholes backfilled with cuttings form an inadequate seal and allow other aquifers to influence the water level and water quality in that well. Another outdated practice included well construction using telescoped casing. Telescoped casing uses a reducer to trim the well to a smaller diameter casing at depth apparently to save money during well construction. Telescoped wells are very susceptible to blockage at the depth of the reducer. Approximately 152 wells in the network were constructed with reducers. DWR has implemented a long-term program for replacing damaged or unsuitably constructed wells with new properly constructed wells. In addition to replacing monitoring wells, DWR was able to repair wells in order to make them usable. The following wells were repaired between February and June 2012: • Winsteadville Station, Beaufort County, O15N5, replaced outer casing & shale trap; • Clark’s Station, Craven County, S22J5, replaced/repaired shale trap; • Arapahoe Station, Pamlico County, S18U10, removed bent casing and replaced with new casing and; • Cox Crossroads Station, Beaufort County, P19M4, installed shale trap and installed protective sleeve on outer casing. The shale trap is a bell shaped piece of rubber which is clamped to the PVC casing and placed below the damaged area of the well. The inside of the shale trap is grouted from where it is attached to the casing to the surface, in order to seal the damaged area of the well and maintain the well’s integrity. Well Development Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 10 Installation of new and replacement monitoring wells occupies a large portion of DWR’s resources. Table 5 lists the new wells installed during the 2011-2012 fiscal year. The new wells are included on Figure 1. 5.5 Automatic Water Level Recorders Automatic water level recorders play an integral role in the DWR monitoring program. They allow for economical collection of near-continuous data at remote well stations. Four primary recorders are utilized and are included Table 6. Hobo including barometer, shuttle and water level indicator Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 11 Sutron including card reader, 12-volt battery and voltage meter Global Water WL16 including iPAQ, field book and calculator Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 12 5.6 Site Surveys Concrete survey monuments continue to be installed at each of the 198 monitoring well stations within the network. Once installation is complete, the monuments will be surveyed using Survey Grade Global Positioning System (GPS) to calculate the most accurate horizontal and vertical location data possible. At the end of the fiscal year, 190 monuments had been installed. It is anticipated that this work will be completed by the end of the year 2012. Surveying of the monuments will take place once monument installation at each well station is complete. 6.0 Planned Activities for FY 2012-2013 6.1 New Well Installation Monitoring well network expansion efforts for FY 2012-2013 will be focused on Beaufort, Bladen, Chowan, Columbus, Duplin, New Hanover, Pender, Pitt, Sampson, Scotland, Washington, and Wayne Counties. In addition, some wells throughout the network that cannot be used due to bad construction, screening in multiple aquifers, etc., may be abandoned during this upcoming fiscal year. Table 7 summarizes the possible upcoming expansion of the network in 2012-2013. 6.2 Well Abandonment The following wells were abandoned during FY 2011-2012: Whitley Farms, Beaufort County, P17E4 and Wilmington Airport, New Hanover County, CC30P2. Gas auger and monument Top of monument - survey point Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 13 7.0 Summary and Conclusions The NCDENR, DWR has maintained and monitored a statewide network of ground water monitoring wells used to assess North Carolina’s ground water supply since 1998. Data collected from the network are available to the public through DWR’s Internet website, www.ncwater.org. These data include, but are not limited to, ground water levels, chloride measurements, well construction information, borehole log construction (lithological and geophysical), ground water monitoring station locations, and geophysical/lithological data collected from other (non-DWR) well sites. The well network consists of 596 monitoring wells at 198 individual stations. From July 2011 through June 2012, ground water level data were collected from 594 wells within the network. These data include manual measurements taken quarterly from wells, plus hourly water levels collected using automatic data recorders from 498 wells. A total of eight monitor wells have been installed at four different stations. One monitoring well was installed at Ivanhoe (Duplin County), one monitoring well was installed at Camp Glenn (Carteret County), one well was installed at Whitley Farms (Beaufort County), and five monitoring wells were installed at Farmville Marlboro Rd. (Pitt County). Borehole advancement and well installation included, but was not limited to, well development and collection of chloride measurements. A total of two wells were abandoned at two different stations: well P17E4 at Whitley Farms, Beaufort County and well CC30P2 at Wilmington Airport, New Hanover County. Archived water level recorder charts obtained from the DWQ with records dating from the 1960s through 1980s continue to be digitized and data recorded into the DWR online database. Survey monuments continue to be installed at each of the well stations with plans to survey each monument using Survey Grade GPS. The triennial chloride sampling was performed on 245 wells in September/October 2010. Thirteen additional samples were collected from the new well installations between in December and May 2011. One additional sample was collected from the new installation in April 2012. Sampling results indicated that there continues to be concern for saltwater encroachment especially near larger pumping centers located near the fresh-salt water interface. Chloride sampling will occur again in September 2012. DWR has tentative plans to expand the monitoring well network by installing thirteen to twenty-six wells at seven to ten sites in fiscal year 2012/2013. In addition several wells in the network may be scheduled for abandonment, replacement, and repair. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report FIGURES Legend New or Improved Monitoring Stations Active Monitoring Stations Regions 1 2 3 4 5 Fall Line 0 50 100 150 200 250 Miles Figure 1: North Carolina Division of Water Resources Monitoring Stations August 2011 NCDENR Division of Water Resources NC Ground Water Resources Monitoring Well Network 2012 Annual Report 0 20,000 40,000 60,000 80,000 100,000 120,000 140,000 160,000 0 100 200 300 400 500 600 700 Number of Daily Water Levels Collected Number of Network Wells Measured Year FIGURE 3 Water&Level&Data&Collected&from&196752012& (Plot&includes&both&DWR&and&USGS&Data)& No. of Wells No. Daily Water levels (includes both DWR and USGS wells) Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLES Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 1 Site Susceptibility Rating North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Susceptibility Rating Description 1 Secure—station is located on State or Federal government property 2 Secure—station is located on local government or school property 3 Moderately secure—station is located on private property, but landowner does not give any indication that land use or property ownership may change 4 Tenuous—station is located on public or private property and landowner is giving indications that land use or property ownership may change 5 Imminent threat—station is on public or private property and landowner desires abandonment of well station. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 2 Site and Recorder Distribution by Region through 6/30/12 North Carolina Division of Ground Water Resources Monitoring Well Network 2012 Annual Report Region Parameter Number % of Region % of Network Wells 122 20.5 Sites 41 20.7 Sutrons 0 0.0 0.0 1 WL15s 0 0.0 0.0 WL16s 50 41.0 8.4 Hobos 48 39.3 8.1 All Recorders 98 80.3 16.4 Wells 154 25.8 Sites 41 20.7 Sutrons 3 1.9 0.5 2 WL15s 19 12.3 3.2 WL16s 50 32.5 8.4 Hobos 55 35.7 9.2 All Recorders 127 82.5 21.3 Wells 112 18.8 Sites 26 13.1 Sutrons 3 2.7 0.5 3 WL15s 4 3.6 0.7 WL16s 42 37.5 7.0 Hobos 25 22.3 4.2 All Recorders 74 66.1 12.4 Wells 131 22.0 Sites 42 21.2 Sutrons 0 0.0 0.0 4 WL15s 9 6.9 1.5 WL16s 24 18.3 4.0 Hobos 46 35.1 7.7 All Recorders 79 60.3 13.3 Wells 77 12.9 Sites 46 23.2 Sutrons 6 7.8 1.0 5 WL15s 10 13.0 1.7 WL16s 16 20.8 2.7 Hobos 29 37.7 4.9 All Recorders 61 79.2 10.2 Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 18 TABLE 3 DWR Monitoring Well Network Statistics (1-1-05) through (6-30-12) North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Parameter 2005 2006 2007 2008 2009 2010 2011 2012 Number of monitored wells 542 544 555 565 575 579 591 594 Manual water levels (tapedowns) 2,633 2,738 2,618 2,468 2,556 2,911 2627 1394 Daily water levels (automatic recorders 89,088 92,827 95,333 107,883 122,969 131,325 136,209 61,746 Total hourly water levels 2,141,368 2,229,355 2,294,909 2,591,483 2,961,371 3,163,229 3,276,498 1,479,961 Chloride Samples 17 22 175 12 17 251 21 1 Geophysical & lithologic logs at new stations 2 1 3 1 1 0 2 1 Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 19 TABLE 4 Chloride Field Analysis to Date Wells Q16G4, Y25Q4, J22P5 and R23X9 Ground Water Resources Monitoring Well Network 2012 Annual Report Station Date Chlorides (ppm) 10/04/2010 531 10/01/2007 564 Godley 09/15/2004 137 Station 10/07/1999 91 Q16G4 07/14/1998 174 02/23/1981 No Reading Available 09/22/2010 BDL of 33 09/25/2007 252 Folkstone 09/14/2004 266 Station 10/12/1999 35 Y25Q4 08/06/1998 11 09/25/1982 No Reading Available 10/04/2010 54 Gold Point 09/24/2007 162 Station 09/30/2004 BDL of 28 ** J22P5 09/15/2004 BDL of 28 06/10/2002 10 09/20/2010 463 Cove City 10/05/2007 352 Station 09/13/2004 309 R23X9 10/04/2000 30 Chloride Level for Salt Water 250 **Collected after well development Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 20 TABLE 5 Well Construction Information Ivanhoe, Sampson County, Camp Glenn, Carteret County, Whitley Farms, Beaufort County and Farmville Marlboro Rd., Pitt North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Well ID Station Name Date Installed Well Diameter (inches) Well Depth (ft bls) Screened Interval (x to y ft bls) Measuring Pt. (MP) (ft) Aquifer Water Level (from MP) (ft) Measured - 6/26/12 Y34P7 Ivanhoe 04/13/12 4 135 110-130 2.92 Pee Dee 5.55 Measured – 5/23/12 X17J7 Camp Glenn 03/27/12 4 17 10-15 3.00 Surficial 7.36 Measured – 5/29/12 P17E5 Whitley Farms 04/19/12 4 35 20-30 2.79 Surficial 9.05 M27U13 Farmville Marlboro Rd. 05/15/12 4 329 314-324 2.98 To Be Determined Not Measured M27U14 Farmville Marlboro Rd. 05/29/12 4 245 230-240 2.82 To Be Determined Not Measured M27U15 Farmville Marlboro Rd. 06/06/12 4 145 130-140 2.96 To Be Determined Not Measured M27U16 Farmville Marlboro Rd. 05/07/12 4 55 40-50 3.13 To Be Determined Not Measured M27U17 Farmville Marlboro Rd. 05/03/12 4 30 15-25 2.96 Surficial Not Measured Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report 21 TABLE 6 Automatic Water Level Recorders North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Recorder Type Number in Service* Sutron Corporation Model 8400A 12 Global Water Instrumentation, Inc. Model WL15 42 Global Water Instrumentation, Inc. Model WL16 182 HOBO U20 Water Level Logger (including separate barometer per station installed 262 (59 barometers) *As of June 30, 2012 Note: Due to the large number of recorders employed by DWR, there are, at any given time, a number of units that are being serviced or replaced. These units are not reflected in the above totals. Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 FY 2012-2013 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 100-110 Yorktown Pocosin Lake Area Washington 200-210 Castle Hayne (upper) 350-360 Castle Hayne (lower saltwater) 500-510 Beaufort 600 Pilot Hole Ivanhoe Sampson 440-450 Upper Cape Fear 20-30 Surficial Vicinity of Walnut 45-55 Black Creek or Surficial Creek Wayne 100-110 Black Creek 220-230 Upper Cape Fear 350 Pilot Hole (Top of Basement) Burgaw Pender 20-30 Surficial 630-640 Upper Cape Fear Kelly Bladen 280-290 Surficial 448-458 Upper Cape Fear 20-30 Surficial 90-100 Castle Hayne North Central New Hanover County New Hanover 220-230 Upper Pee Dee 350-360 Lower Pee Dee 450 Pilot Hole Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 (continued) FY 2011-2012 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 30-40 Pee Dee Vicinity of Faison/Warsaw Northwestern Duplin County 140-150 Black Creek 265-275 Upper Cape Fear 400-410 Lower Cape Fear 448 Pilot Hole 20-30 Surficial 80-90 Yorktown Between DWR Godley and Aurora Beaufort 250-260 Castle Hayne (upper) 440-450 Castle Hayne (lower) 610-620 Beaufort 650-660 Pee Dee 700 Pilot Hole 20-30 Surficial Nakina Columbus 380-390 Black Creek 844-854 Lower Cape Fear 20-30 Surficial USGS Core Hole Site at Fort Fisher/Kure Beach New Hanover 95-105 Castle Hayne 160-170 Pee Dee Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 (continued) FY 2011-2012 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 110-120 Pee Dee Vicinity of Moore’s Creek National Park Pender County 330-340 Black Creek 590-600 Upper Cape Fear 630 Pilot Hole 20-30 Surficial Turkey Sampson 318-328 Upper Cape Fear 432-442 Lower Cape Fear 20-30 Surficial Vicinity of Salemburg Sampson 80-90 Black Creek 206-216 Upper Cape Fear 20-30 Surficial Town of Laurinburg Scotland 120-130 Black Creek 332-342 Upper Black Creek 20-30 Surficial 80-90 Yorktown Vicinity of Valhalla Chowan 220-230 Castle Hayne 320-330 Beaufort 450-460 Upper Cape Fear 850-860 Lower Cape Fear 1200-1210 Lower Cretaceous 1300 Pilot Hole Division of Water Resources NC Ground Water Resources Monitoring Well Network September 2012 2012 Annual Report TABLE 7 (continued) FY 2011-2012 Network Expansion North Carolina Ground Water Resources Monitoring Well Network 2012 Annual Report Station Name/Quad County Proposed New Well Screens (ft bls) Aquifer 20-30 Surficial 124-134 Yorktown 244-254 Castle Hayne (upper) Belhaven Beaufort 312-322 Castle Hayne (lower) 388-398 Beaufort 540-550 Pee Dee 720-730 Black Creek 900 Pilot 20-30 Surficial 46-56 Yorktown River Park North Pitt 110-120 Pee Dee 150-160 Upper Black Creek 252-262 Lower Black Creek 380-390 Upper Cape Fear |
OCLC number | 840919482 |