Acquisition Activity and Raw Data Report on 1997 Annual Water Level Measurements: Kansas Geological Survey's Portion
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The primary measurement trip was completed in nine days by a crew of six people (Figure 2). Each person was equipped with a vehicle, GPS, field notes, maps, steel measuring tape, and associated miscellaneous supplies. The far northwestern counties (Cheyenne, Sherman, and Wallace) were completed during the first two days, requiring overnights in St. Francis, Goodland, and Syracuse. The third day of measurements ended in Garden City and saw the completion of measurements in three counties (Hamilton, Kearny, and Grant). The fifth field day began in Garden City and ended in Liberal with completion of one county (Finney). The sixth day ended in Meade, with four more counties (Seward, Stevens, Haskell, and Grant) completed. The seventh day concluded in Dodge City after completing one more county (Meade). The eighth and ninth days both ended in Larned finishing five counties on the eighth day (Ford, Gray, Finney, Hodgeman, and Ness) and the last two counties (Pawnee and Barton) on the ninth day.
The six crew members were divided into three teams (Figure 2). Each team was responsible for 18 to 32 wells per day along predesignated closed routes. The routes were designed so team members would meet somewhere along the route. Team members met along the route after all the wells on a route were visited. This method attempts to balance workloads by compensating for differing degrees of measuring difficulty (variable amounts of time necessary to actually measure individual wells), insures no wells were overlooked during the primary measurement trip, and minimizes the number of miles traveled per well. Once a team had completed its route, the other teams were contacted to determine if assistance was necessary to insure all routes were completed prior to sunset. Distribution of the crew members was such that no crew member was more than 15 to 20 miles from another crew member. This pro-vided increased safety and minimized the time necessary to complete a county. Once a team completed their route and any assistance requested, they proceeded to a pre-designated motel. The day's work sheets, route maps, and GPS measurements were collected and checked for completeness and problems encountered. Approximately 12,700 miles were logged during the primary measurement trip with the average crew member visiting 11.7 wells per day and spending about 55 minutes per well (average time per well values include on-site and travel time).
The QA/QC trip was completed in four days by three people. The QC covered 14 counties and included 72 wells (Figure 4). The QC re-visits resulted in confirmation or successful measurements on 62 wells previously unmeasurable or out-of-trend as determined from primary measurement trip data. Final measurements at these 62 wells took an average of nearly two hours per well and as a group were situated along routes that required a total of about 4,160 miles of vehicle travel to visit. QC re-visit wells were determined through careful examination of primary trip measurements, remeasuring any well that met at least one of the following criteria:
Well and Measurement Point Information
As part of the KGS portion of the 1997 annual measurement program, a few well statistics have been noted for incorporation into future efforts to improve the overall quality of the network. The wells measured include 405 irrigation wells, 102 unused wells (monitor or abandoned), 23 stock wells, and 8 household wells. Of the 562 wells included in the 1997 acquisition list, 64 were measured through a slant pipe, 21 through measurement tubes, 336 through access holes on or within the pump base, 114 directly into open casing, and 23 with flip-style covers over access holes. The water depth distribution places 206 wells with recorded depths less than 100 ft, 243 between 100 and 200 ft, 79 between 200 and 300 ft, and 14 with measured depths greater than 300 ft. Drill depth of measured wells is also an important characteristic. For the group of wells reported here, 97 wells have an unknown depth while 85 are less than 100 ft, 89 are between 100 ft and 200 ft, 128 are between 200 and 300, 91 are between 300 and 400, and 72 are greater than 400 ft.
Unique to the 1997 measurement program was the recording of latitude and longitude using a handheld GPS unit and photographing of each well site. A total of 537 GPS-determined latitudes and longitudes were recorded at wells measured during January 1997. Photographs of 512 wells will be used to provide a visual record for future measurements. Incorporation of the GPS system, detailed site comments, and photographs into a digital database will greatly enhance well familiarity and identification regardless of experience with a particular well. On-site information available digitally will include not only photographs, but also measurement subtleties, downhole dangers, environmental cautions, and other concerns/comments of previous measurers.
During the 1997 measurement program several characteristics of each measurement were recorded for each well. The presence of oil on the water was encountered in 86 (15 percent) of the measured wells in sufficient quantity to be easily recognizable on the measurement tape. Also noted were the ease of access to the measurement point and downhole access. Seventy-three wells had difficult downhole access; 60 had difficult measurement point access. Of the 562 wells with attempted measure-ments during the 1997 campaign, 130 were reported as difficult to measure with prob-lems such as hangs, restrictions, snags, or catches.
An attempt was made this year to provide feedback on the quality of individual measurement. If confidence in the measurement was not high or if the measurement did not fall within the local and/or historical trends, a remeasurement was made. A total of 446 wells were measured once, 73 wells had two measurements, 17 had three, and six had four depths to water calculated. A total of 745 measurements were made during primary and QC measurement trips. Another 48 measurements were made during the QA visits. The actual water line left on the tape after retrieving it from a well was judged based on sharpness and the interpreter's confidence in the location where the water marked (or cut) the chalk on the steel tape. A total of 341 measurements were judged to be excellent, 162 good, and 39 fair. Comparing measurement quality and consistency provides insight into the accuracy of interpre-tations made using this data set.
A great deal of significance has been placed on the historical record of individual wells. In field determinations of measurement, quality was based in part on the previous three years' water levels. Thirty-eight wells were measured in 1997 that were not measured as part of the 1996 annual measurement program. Eleven measured in 1997 were not measured in 1996 or 1995 and one measured in 1997 had not been measured in 1996, 1995, or 1994. In reverse, 12 wells measured during the 1996 annual program were not measured in 1997.
A issue of importance for maintaining the long-term health of the network is the identification of wells needing replacements and immediate identification of acceptable replacements. The well replacement process allows current spatial distributions to be maintained. A total of 23 wells have been identified as strong candidates for replacement (Table 1). Of the 23 wells in need of replacement, 11 were unmeasurable in 1997 but have recorded measurements in 1996. Nine of the remaining 12 have not been measured in at least the last two years. The remaining three were measured during 1997 but due to plugging or access difficul-ties will not be visited as part of the 1998 annual measurement program.
Table 1--Wells Requiring Replacement and Reason
|03S 40W 09BAA||Measurement questionable.|
|03S 42W 26CCD||Bad obstruction at ~170 ft.|
|07S 41W 07BCB||Well sounder stuck in well.|
|22S 24W 14BBC||Various restrictions. Cannot measure.|
|22S 24W 16ADB||Collapsed well.|
|22S 39W 03BBB||Dirt filled in up to ~181 ft.|
|24S 32W 35DD||Pumping daily for Brookover Inc.|
|24S 33W 22BCC||Reported by property manager to be cemented.|
|26S 24W 32CBA||Cannot find. Referenced windmill is gone.|
|26S 31W 36CAB||Dry well confirmed by landowner.|
|27S 38W 23CBB||Took alternate well, cannot find 23CBB.|
|28S 34W 15DAB||Dry well. No major obstructions.|
|28S 35W 05BCC||Well plugged. Irrigation well 40 ft away, but with many restrictions, cannot measure.|
|29S 32W 19CCC||Rex Brown's well. Too crooked to continue measuring.|
|29S 32W 26CBB||Tape hung at 290 ft. Cannot get past obstruction.|
|30S 29W 23CAD||Dry well. Tape hangs at 200 ft and cannot get past.|
|30S 31W 24BBC||Reported plugged by landowner.|
|31S 32W 03DAD||Various restrictions; cannot measure.|
|31S 34W 18BBB||Got measurement, but bad catches at 20 ft intervals.|
|32S 38W 23BDD||Casing broken off. Well recently covered.|
|32S 39W 02BBB||No blockage, no water, no measurement.|
|33S 36W 26DDD||Dry, no measurement possible.|
|33S 37W 23CDB||Cannot find.|
1997 Water Levels
A total of 542 of the 562 wells that make up the KGS portion of the 1997 annual water level measurement program have confident depth-to-water levels reported in this document (Appendix A). Wells are divided by county and then cataloged according to well ID (township, range, section system). The levels reported in Appendix A represent the highest confidence measurement taken at that well during the annual measurement period. In some cases a single well may have as many as four recorded measurements. Determination of the best value was made by the field person(s) who measured the well. The best measurement on each well was based on quality of cut, difficulty reaching the hold line and retrieving the tape from below water level, pre-cut moisture, level of confidence that the tape was hanging unimpaired in the borehole, and accuracy of measurement point hold. No weight was given to historical or local water level trends.
The data in its most basic form includes the tape hold, water cut, and measurement point correction for each measurement taken at a particular well (Appendix B). Each well is listed by county and includes all primary measurement data and any QC re-visit data and QA measurements. In a few cases depth to water as calculated in Appendix B will not be consistent with measurements made by the Division of Water Resources (DWR) in equivalent wells. This is due to the fact that some DWR depth to water values are not corrected for measurement point elevation. In such a case, since the hold and cut are known, by adding the MP correction to the KGS calculated depth to water, direct comparisons can be made.
Direct comparison of primary measurements and the QA measurements reveals important information about the accuracy of the database as a whole (Appendix C). The 48 wells with both primary and QA measurements are listed without measurement dates. In general, the time separation between the primary measurements and the QA measurements is about 10 days to two weeks.
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