A new method was developed for conducting aquifer tests in fractured-rock flow systems that have a pump-and-treat (P&T) operation for containing and removing groundwater contaminants. The method involves temporary shutdown of individual pumps in wells of the P&T system. Conducting aquifer tests in this manner has several advantages, including (1) no additional contaminated water is withdrawn, and (2) hydraulic containment of contaminants remains largely intact because pumping continues at most wells. The well-shutdown test method was applied at the former Naval Air Warfare Center (NAWC), West Trenton, New Jersey, where a P&T operation is designed to contain and remove trichloroethene and its daughter products in the dipping fractured sedimentary rocks underlying the site. The detailed site-scale subsurface geologic stratigraphy, a three-dimensional MODFLOW model, and inverse methods in UCODE_2005 were used to analyze the shutdown tests. In the model, a deterministic method was used for representing the highly heterogeneous hydraulic conductivity distribution and simulations were conducted using an equivalent porous media method. This approach was very successful for simulating the shutdown tests, contrary to a common perception that flow in fractured rocks must be simulated using a stochastic or discrete fracture representation of heterogeneity. Use of inverse methods to simultaneously calibrate the model to the multiple shutdown tests was integral to the effectiveness of the approach.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2009.00651.x","usgsCitation":"Tiedeman, C.R., Lacombe, P., and Goode, D., 2010, Multiple well-shutdown tests and site-scale flow simulation in fractured rocks: Groundwater, v. 48, no. 3, p. 401-415, https://doi.org/10.1111/j.1745-6584.2009.00651.x.","productDescription":"15 p.","startPage":"401","endPage":"415","ipdsId":"IP-014165","costCenters":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":332770,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"48","issue":"3","noUsgsAuthors":false,"publicationDate":"2010-04-28","publicationStatus":"PW","scienceBaseUri":"586cc698e4b0f5ce109fa95b","contributors":{"authors":[{"text":"Tiedeman, Claire R. 0000-0002-0128-3685 tiedeman@usgs.gov","orcid":"https://orcid.org/0000-0002-0128-3685","contributorId":196777,"corporation":false,"usgs":true,"family":"Tiedeman","given":"Claire","email":"tiedeman@usgs.gov","middleInitial":"R.","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":657371,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lacombe, Pierre J. placombe@usgs.gov","contributorId":2486,"corporation":false,"usgs":true,"family":"Lacombe","given":"Pierre J.","email":"placombe@usgs.gov","affiliations":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"preferred":false,"id":657372,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Goode, Daniel J. 0000-0002-8527-2456 djgoode@usgs.gov","orcid":"https://orcid.org/0000-0002-8527-2456","contributorId":2433,"corporation":false,"usgs":true,"family":"Goode","given":"Daniel J.","email":"djgoode@usgs.gov","affiliations":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"preferred":false,"id":657373,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70037608,"text":"70037608 - 2010 - Simulation and analysis of conjunctive use with MODFLOW's farm process","interactions":[],"lastModifiedDate":"2018-09-18T10:19:23","indexId":"70037608","displayToPublicDate":"2010-01-01T00:00:00","publicationYear":"2010","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Simulation and analysis of conjunctive use with MODFLOW's farm process","docAbstract":"The extension of MODFLOW onto the landscape with the Farm Process (MF-FMP) facilitates fully coupled simulation of the use and movement of water from precipitation, streamflow and runoff, groundwater flow, and consumption by natural and agricultural vegetation throughout the hydrologic system at all times. This allows for more complete analysis of conjunctive use water-resource systems than previously possible with MODFLOW by combining relevant aspects of the landscape with the groundwater and surface water components. This analysis is accomplished using distributed cell-by-cell supply-constrained and demand-driven components across the landscape within \" water-balance subregions\" comprised of one or more model cells that can represent a single farm, a group of farms, or other hydrologic or geopolitical entities. Simulation of micro-agriculture in the Pajaro Valley and macro-agriculture in the Central Valley are used to demonstrate the utility of MF-FMP. For Pajaro Valley, the simulation of an aquifer storage and recovery system and related coastal water distribution system to supplant coastal pumpage was analyzed subject to climate variations and additional supplemental sources such as local runoff. For the Central Valley, analysis of conjunctive use from different hydrologic settings of northern and southern subregions shows how and when precipitation, surface water, and groundwater are important to conjunctive use. The examples show that through MF-FMP's ability to simulate natural and anthropogenic components of the hydrologic cycle, the distribution and dynamics of supply and demand can be analyzed, understood, and managed. This analysis of conjunctive use would be difficult without embedding them in the simulation and are difficult to estimate a priori. Journal compilation ?? 2010 National Ground Water Association. No claim to original US government works.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ground Water","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1745-6584.2010.00730.x","issn":"0017467X","usgsCitation":"Hanson, R.T., Schmid, W., Faunt, C., and Lockwood, B., 2010, Simulation and analysis of conjunctive use with MODFLOW's farm process: Ground Water, v. 48, no. 5, p. 674-689, https://doi.org/10.1111/j.1745-6584.2010.00730.x.","startPage":"674","endPage":"689","numberOfPages":"16","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":218064,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1745-6584.2010.00730.x"},{"id":246044,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"48","issue":"5","noUsgsAuthors":false,"publicationDate":"2010-06-22","publicationStatus":"PW","scienceBaseUri":"505b8fe4e4b08c986b3191d6","contributors":{"authors":[{"text":"Hanson, R. T.","contributorId":91148,"corporation":false,"usgs":true,"family":"Hanson","given":"R.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":461895,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schmid, W.","contributorId":103479,"corporation":false,"usgs":true,"family":"Schmid","given":"W.","email":"","affiliations":[],"preferred":false,"id":461897,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Faunt, C.C. 0000-0001-5659-7529","orcid":"https://orcid.org/0000-0001-5659-7529","contributorId":103314,"corporation":false,"usgs":true,"family":"Faunt","given":"C.C.","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":461896,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lockwood, B.","contributorId":59660,"corporation":false,"usgs":true,"family":"Lockwood","given":"B.","email":"","affiliations":[],"preferred":false,"id":461894,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70003362,"text":"70003362 - 2009 - Investigating hydraulic connections and the origin of water in a mine tunnel using stable isotopes and hydrographs","interactions":[],"lastModifiedDate":"2021-03-25T18:36:07.567184","indexId":"70003362","displayToPublicDate":"2012-05-27T11:42:00","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":835,"text":"Applied Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Investigating hydraulic connections and the origin of water in a mine tunnel using stable isotopes and hydrographs","docAbstract":"Turquoise Lake is a water-supply reservoir located north of the historic Sugarloaf Mining district near Leadville, Colorado, USA. Elevated water levels in the reservoir may increase flow of low-quality water from abandoned mine tunnels in the Sugarloaf District and degrade water quality downstream. The objective of this study was to understand the sources of water to Dinero mine drainage tunnel and evaluate whether or not there was a direct hydrologic connection between Dinero mine tunnel and Turquoise Lake from late 2002 to early 2008. This study utilized hydrograph data from nearby draining mine tunnels and the lake, and stable isotope (δ18O and δ2H) data from the lake, nearby draining mine tunnels, imported water, and springs to characterize water sources in the study area. Hydrograph results indicate that flow from the Dinero mine tunnel decreased 26% (2006) and 10% (2007) when lake elevation (above mean sea level) decreased below approximately 3004 m (approximately 9855 feet). Results of isotope analysis delineated two meteoric water lines in the study area. One line characterizes surface water and water imported to the study area from the western side of the Continental Divide. The other line characterizes groundwater including draining mine tunnels, springs, and seeps. Isotope mixing calculations indicate that water from Turquoise Lake or seasonal groundwater recharge from snowmelt represents approximately 10% or less of the water in Dinero mine tunnel. However, most of the water in Dinero mine tunnel is from deep groundwater having minimal isotopic variation. The asymmetric shape of the Dinero mine tunnel hydrograph may indicate that a limited mine pool exists behind a collapse in the tunnel and attenutates seasonal recharge. Alternatively, a conceptual model is presented (and supported with MODFLOW simulations) that is consistent with current and previous data collected in the study area, and illustrates how fluctuating lake levels change the local water-table elevation which can affect discharge from the Dinero mine tunnel without physical transfer of water between the two locations.","language":"English","publisher":"Elsevier","doi":"10.1016/j.apgeochem.2009.09.015","usgsCitation":"Walton-Day, K., and Poeter, E., 2009, Investigating hydraulic connections and the origin of water in a mine tunnel using stable isotopes and hydrographs: Applied Geochemistry, v. 24, no. 12, p. 2266-2282, https://doi.org/10.1016/j.apgeochem.2009.09.015.","productDescription":"17 p.","startPage":"2266","endPage":"2282","temporalStart":"2002-01-01","temporalEnd":"2008-12-31","costCenters":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":257154,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","city":"Leadville","otherGeospatial":"Turquoise Lake","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -106.4688491821289,\n 39.19581074223468\n ],\n [\n -106.28929138183594,\n 39.19581074223468\n ],\n [\n -106.28929138183594,\n 39.313581716526485\n ],\n [\n -106.4688491821289,\n 39.313581716526485\n ],\n [\n -106.4688491821289,\n 39.19581074223468\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"24","issue":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3e68e4b0c8380cd63d63","contributors":{"authors":[{"text":"Walton-Day, Katherine 0000-0002-9146-6193","orcid":"https://orcid.org/0000-0002-9146-6193","contributorId":68339,"corporation":false,"usgs":true,"family":"Walton-Day","given":"Katherine","affiliations":[],"preferred":false,"id":347022,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Poeter, Eileen","contributorId":24616,"corporation":false,"usgs":true,"family":"Poeter","given":"Eileen","affiliations":[],"preferred":false,"id":347021,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":98027,"text":"tm6A33 - 2009 - GWM-2005 - A Groundwater-Management Process for MODFLOW-2005 with Local Grid Refinement (LGR) Capability","interactions":[],"lastModifiedDate":"2012-02-02T00:15:03","indexId":"tm6A33","displayToPublicDate":"2009-12-04T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":335,"text":"Techniques and Methods","code":"TM","onlineIssn":"2328-7055","printIssn":"2328-7047","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"6-A33","title":"GWM-2005 - A Groundwater-Management Process for MODFLOW-2005 with Local Grid Refinement (LGR) Capability","docAbstract":"This report describes the Groundwater-Management (GWM) Process for MODFLOW-2005, the 2005 version of the U.S. Geological Survey modular three-dimensional groundwater model. GWM can solve a broad range of groundwater-management problems by combined use of simulation- and optimization-modeling techniques. These problems include limiting groundwater-level declines or streamflow depletions, managing groundwater withdrawals, and conjunctively using groundwater and surface-water resources. GWM was initially released for the 2000 version of MODFLOW.\r\n\r\nSeveral modifications and enhancements have been made to GWM since its initial release to increase the scope of the program's capabilities and to improve its operation and reporting of results. The new code, which is called GWM-2005, also was designed to support the local grid refinement capability of MODFLOW-2005. Local grid refinement allows for the simulation of one or more higher resolution local grids (referred to as child models) within a coarser grid parent model. Local grid refinement is often needed to improve simulation accuracy in regions where hydraulic gradients change substantially over short distances or in areas requiring detailed representation of aquifer heterogeneity. GWM-2005 can be used to formulate and solve groundwater-management problems that include components in both parent and child models. Although local grid refinement increases simulation accuracy, it can also substantially increase simulation run times.","language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/tm6A33","usgsCitation":"Ahlfeld, D.P., Baker, K.M., and Barlow, P.M., 2009, GWM-2005 - A Groundwater-Management Process for MODFLOW-2005 with Local Grid Refinement (LGR) Capability: U.S. Geological Survey Techniques and Methods 6-A33, viii, 67 p., https://doi.org/10.3133/tm6A33.","productDescription":"viii, 67 p.","costCenters":[{"id":327,"text":"Groundwater Resources Program","active":false,"usgs":true}],"links":[{"id":125698,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/tm_6_a33.gif"},{"id":13225,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/tm/tm6a33/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b28e4b07f02db6b146b","contributors":{"authors":[{"text":"Ahlfeld, David P.","contributorId":49464,"corporation":false,"usgs":true,"family":"Ahlfeld","given":"David","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":303936,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Baker, Kristine M.","contributorId":21250,"corporation":false,"usgs":true,"family":"Baker","given":"Kristine","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":303935,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Barlow, Paul M. 0000-0003-4247-6456 pbarlow@usgs.gov","orcid":"https://orcid.org/0000-0003-4247-6456","contributorId":1200,"corporation":false,"usgs":true,"family":"Barlow","given":"Paul","email":"pbarlow@usgs.gov","middleInitial":"M.","affiliations":[{"id":493,"text":"Office of Ground Water","active":true,"usgs":true}],"preferred":true,"id":303934,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98023,"text":"sir20095063 - 2009 - Hydrogeology and Simulation of Groundwater Flow in the Plymouth-Carver-Kingston-Duxbury Aquifer System, Southeastern Massachusetts","interactions":[],"lastModifiedDate":"2018-05-17T13:38:48","indexId":"sir20095063","displayToPublicDate":"2009-12-04T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-5063","title":"Hydrogeology and Simulation of Groundwater Flow in the Plymouth-Carver-Kingston-Duxbury Aquifer System, Southeastern Massachusetts","docAbstract":"The glacial sediments that underlie the Plymouth-Carver-Kingston-Duxbury area of southeastern Massachusetts compose an important aquifer system that is the primary source of water for a region undergoing rapid development. Population increases and land-use changes in this area has led to two primary environmental effects that relate directly to groundwater resources: (1) increases in pumping that can adversely affect environmentally sensitive groundwater-fed surface waters, such as ponds, streams, and wetlands; and (2) adverse effects of land use on the quality of water in the aquifer. In response to these concerns, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, began an investigation in 2005 to improve the understanding of the hydrogeology in the area and to assess the effects of changing pumping and recharge conditions on groundwater flow in the Plymouth-Carver-Kingston-Duxbury aquifer system.\r\n\r\nA numerical flow model was developed based on the USGS computer program MODFLOW-2000 to assist in the analysis of groundwater flow. Model simulations were used to determine water budgets, flow directions, and the sources of water to pumping wells, ponds, streams, and coastal areas.\r\n\r\nModel-calculated water budgets indicate that approximately 298 million gallons per day (Mgal/d) of water recharges the Plymouth-Carver-Kingston-Duxbury aquifer system. Most of this water (about 70 percent) moves through the aquifer, discharges to streams, and then reaches the coast as surface-water discharge. Of the remaining 30 percent of flow, about 25 percent of the water that enters the aquifer as recharge discharges directly to coastal areas and 5 percent discharges to pumping wells.\r\n\r\nGroundwater withdrawals are anticipated to increase from the current (2005) rate of about 14 Mgal/d to about 21 Mgal/d by 2030. Pumping from large-capacity production wells decreases water levels and increases the potential for effects on surface-water bodies, which are affected by pumping and wastewater disposal locations and rates. Pumping wells that are upgradient of surface-water bodies potentially capture water that would otherwise discharge to these surface-water bodies, thereby reducing streamflow and pond levels. The areas most affected by proposed increases in groundwater withdrawals are in the Towns of Plymouth and Wareham where more than half of the proposed increase in pumping will occur.\r\n\r\nIn response to an increase of about 7 Mgal/d of pumping, groundwater discharge to streams is reduced by about 6 cubic feet per second (ft3/s) (about 4 Mgal/d) from a total of about 325 ft3/s. Reduction in streamflow is moderated by an increase of artificial recharge from wastewater returned to the aquifer by onsite domestic septic systems and centralized wastewater treatment facilities. It is anticipated that about 3 Mgal/d of the 7 Mgal/d of increase in pumped water will be returned to the aquifer as wastewater by 2030.\r\n\r\nCurrently (2005) about 3 percent of groundwater discharge to streams is from wastewater return flow to the aquifer during average conditions. During drought conditions, the component of streamflow augmented by wastewater return flow doubles as wastewater recharge remains constant and aquifer recharge rates decrease. Wastewater return flow, whether as direct groundwater discharge to streams or as an additional source of aquifer recharge, increases the height of the water table near streams, thereby moderating the effects of increased groundwater withdrawals on streamflow.\r\n\r\nAn analysis of a simulated drought similar to the 1960s drought of record indicates that the presence of streams moderates the effects on water levels of reduced aquifer recharge. The area where water-table altitudes were least affected by drought was in the Weweantic River watershed in the Town of Carver. Water levels decreased by less than 2 feet from current average conditions compared to decreases of greater than 5","language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/sir20095063","isbn":"9781411324336","collaboration":"Prepared in cooperation with the Massachusetts Department of Environmental Protection-Drinking Water Program","usgsCitation":"Masterson, J., Carlson, C.S., Walter, D.A., Other contributing authors: Bent, G.C., and Massey, A.J., 2009, Hydrogeology and Simulation of Groundwater Flow in the Plymouth-Carver-Kingston-Duxbury Aquifer System, Southeastern Massachusetts: U.S. Geological Survey Scientific Investigations Report 2009-5063, vi, 111 p., https://doi.org/10.3133/sir20095063.","productDescription":"vi, 111 p.","costCenters":[{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"links":[{"id":125592,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2009_5063.jpg"},{"id":13221,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2009/5063/","linkFileType":{"id":5,"text":"html"}}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -70.91666666666667,41.666666666666664 ], [ -70.91666666666667,42.166666666666664 ], [ -70.41666666666667,42.166666666666664 ], [ -70.41666666666667,41.666666666666664 ], [ -70.91666666666667,41.666666666666664 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4de4b07f02db6277a7","contributors":{"authors":[{"text":"Masterson, John P. 0000-0003-3202-4413 jpmaster@usgs.gov","orcid":"https://orcid.org/0000-0003-3202-4413","contributorId":1865,"corporation":false,"usgs":true,"family":"Masterson","given":"John P.","email":"jpmaster@usgs.gov","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":false,"id":303926,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Carlson, Carl S. 0000-0001-7142-3519 cscarlso@usgs.gov","orcid":"https://orcid.org/0000-0001-7142-3519","contributorId":1694,"corporation":false,"usgs":true,"family":"Carlson","given":"Carl","email":"cscarlso@usgs.gov","middleInitial":"S.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303924,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Walter, Donald A. 0000-0003-0879-4477 dawalter@usgs.gov","orcid":"https://orcid.org/0000-0003-0879-4477","contributorId":1101,"corporation":false,"usgs":true,"family":"Walter","given":"Donald","email":"dawalter@usgs.gov","middleInitial":"A.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303923,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Other contributing authors: Bent, Gardner C.","contributorId":106219,"corporation":false,"usgs":true,"family":"Other contributing authors: Bent","given":"Gardner","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":303927,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Massey, Andrew J. 0000-0003-3995-8657 ajmassey@usgs.gov","orcid":"https://orcid.org/0000-0003-3995-8657","contributorId":1862,"corporation":false,"usgs":true,"family":"Massey","given":"Andrew","email":"ajmassey@usgs.gov","middleInitial":"J.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303925,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":97937,"text":"sir20095205 - 2009 - Numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units in the Rapid City area, South Dakota","interactions":[],"lastModifiedDate":"2017-10-14T12:08:31","indexId":"sir20095205","displayToPublicDate":"2009-10-22T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-5205","title":"Numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units in the Rapid City area, South Dakota","docAbstract":"The city of Rapid City and other water users in the Rapid City area obtain water supplies from the Minnelusa and Madison aquifers, which are contained in the Minnelusa and Madison hydrogeologic units. A numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units in the Rapid City area was developed to synthesize estimates of water-budget components and hydraulic properties, and to provide a tool to analyze the effect of additional stress on water-level altitudes within the aquifers and on discharge to springs. This report, prepared in cooperation with the city of Rapid City, documents a numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units for the 1,000-square-mile study area that includes Rapid City and the surrounding area.\r\n\r\nWater-table conditions generally exist in outcrop areas of the Minnelusa and Madison hydrogeologic units, which form generally concentric rings that surround the Precambrian core of the uplifted Black Hills. Confined conditions exist east of the water-table areas in the study area.\r\n\r\nThe Minnelusa hydrogeologic unit is 375 to 800 feet (ft) thick in the study area with the more permeable upper part containing predominantly sandstone and the less permeable lower part containing more shale and limestone than the upper part. Shale units in the lower part generally impede flow between the Minnelusa hydrogeologic unit and the underlying Madison hydrogeologic unit; however, fracturing and weathering may result in hydraulic connections in some areas. The Madison hydrogeologic unit is composed of limestone and dolomite that is about 250 to 610 ft thick in the study area, and the upper part contains substantial secondary permeability from solution openings and fractures. Recharge to the Minnelusa and Madison hydrogeologic units is from streamflow loss where streams cross the outcrop and from infiltration of precipitation on the outcrops (areal recharge).\r\n\r\nMODFLOW-2000, a finite-difference groundwater-flow model, was used to simulate flow in the Minnelusa and Madison hydrogeologic units with five layers. Layer 1 represented the fractured sandstone layers in the upper 250 ft of the Minnelusa hydrogeologic unit, and layer 2 represented the lower part of the Minnelusa hydrogeologic unit. Layer 3 represented the upper 150 ft of the Madison hydrogeologic unit, and layer 4 represented the less permeable lower part. Layer 5 represented an approximation of the underlying Deadwood aquifer to simulate upward flow to the Madison hydrogeologic unit. The finite-difference grid, oriented 23 degrees counterclockwise, included 221 rows and 169 columns with a square cell size of 492.1 ft in the detailed study area that surrounded Rapid City. The northern and southern boundaries for layers 1-4 were represented as no-flow boundaries, and the boundary on the east was represented with head-dependent flow cells. Streamflow recharge was represented with specified-flow cells, and areal recharge to layers 1-4 was represented with a specified-flux boundary. Calibration of the model was accomplished by two simulations: (1) steady-state simulation of average conditions for water years 1988-97 and (2) transient simulations of water years 1988-97 divided into twenty 6-month stress periods.\r\n\r\nFlow-system components represented in the model include recharge, discharge, and hydraulic properties. The steady-state streamflow recharge rate was 42.2 cubic feet per second (ft3/s), and transient streamflow recharge rates ranged from 14.1 to 102.2 ft3/s. The steady-state areal recharge rate was 20.9 ft3/s, and transient areal recharge rates ranged from 1.1 to 98.4 ft3/s. The upward flow rate from the Deadwood aquifer to the Madison hydrogeologic unit was 6.3 ft3/s. Discharge included springflow, water use, flow to overlying units, and regional outflow. The estimated steady-state springflow of 32.8 ft3/s from seven springs was similar to the simulated springflow of 31.6 ft3/s, which included 20.5 ft3","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/sir20095205","isbn":"9781411325982","collaboration":"Prepared in cooperation with the city of Rapid City","usgsCitation":"Putnam, L.D., and Long, A.J., 2009, Numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units in the Rapid City area, South Dakota: U.S. Geological Survey Scientific Investigations Report 2009-5205, viii, 82 p., https://doi.org/10.3133/sir20095205.","productDescription":"viii, 82 p.","costCenters":[{"id":562,"text":"South Dakota Water Science Center","active":true,"usgs":true},{"id":34685,"text":"Dakota Water Science Center","active":true,"usgs":true}],"links":[{"id":126875,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2009_5205.jpg"},{"id":13109,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2009/5205/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"South Dakota","city":"Rapid City","otherGeospatial":"Madison hydrogeologic unit, Minnelusa unit","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -103.58333333333333,43.833333333333336 ], [ -103.58333333333333,44.416666666666664 ], [ -102.75,44.416666666666664 ], [ -102.75,43.833333333333336 ], [ -103.58333333333333,43.833333333333336 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e48d0e4b07f02db5465e9","contributors":{"authors":[{"text":"Putnam, Larry D. ldputnam@usgs.gov","contributorId":990,"corporation":false,"usgs":true,"family":"Putnam","given":"Larry","email":"ldputnam@usgs.gov","middleInitial":"D.","affiliations":[],"preferred":true,"id":303635,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Long, Andrew J. 0000-0001-7385-8081 ajlong@usgs.gov","orcid":"https://orcid.org/0000-0001-7385-8081","contributorId":989,"corporation":false,"usgs":true,"family":"Long","given":"Andrew","email":"ajlong@usgs.gov","middleInitial":"J.","affiliations":[{"id":622,"text":"Washington Water Science Center","active":true,"usgs":true},{"id":562,"text":"South Dakota Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303634,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":97938,"text":"sir20095172 - 2009 - The Mississippi Embayment Regional Aquifer Study (MERAS): Documentation of a groundwater-flow model constructed to assess water availability in the Mississippi embayment","interactions":[],"lastModifiedDate":"2023-04-18T19:44:21.11773","indexId":"sir20095172","displayToPublicDate":"2009-10-22T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-5172","title":"The Mississippi Embayment Regional Aquifer Study (MERAS): Documentation of a groundwater-flow model constructed to assess water availability in the Mississippi embayment","docAbstract":"The Mississippi Embayment Regional Aquifer Study (MERAS) was conducted with support from the Groundwater Resources Program of the U.S. Geological Survey Office of Groundwater. This report documents the construction and calibration of a finite-difference groundwater model for use as a tool to quantify groundwater availability within the Mississippi embayment. To approximate the differential equation, the MERAS model was constructed with the U.S. Geological Survey's modular three-dimensional finite-difference code, MODFLOW-2005; the preconditioned conjugate gradient solver within MODFLOW-2005 was used for the numerical solution technique. The model area boundary is approximately 78,000 square miles and includes eight States with approximately 6,900 miles of simulated streams, 70,000 well locations, and 10 primary hydrogeologic units. The finite-difference grid consists of 414 rows, 397 columns, and 13 layers. Each model cell is 1 square mile with varying thickness by cell and by layer. The simulation period extends from January 1, 1870, to April 1, 2007, for a total of 137 years and 69 stress periods. The first stress period is simulated as steady state to represent predevelopment conditions.\r\n\r\nAreal recharge is applied throughout the MERAS model area using the MODFLOW-2005 Recharge Package. Irrigation, municipal, and industrial wells are simulated using the Multi-Node Well Package. There are 43 streams simulated by the MERAS model. Each stream or river in the model area was simulated using the Streamflow-Routing Package. The perimeter of the model area and the base of the flow system are represented as no-flow boundaries. The downgradient limit of each model layer is a no-flow boundary, which approximates the extent of water with less than 10,000 milligrams per liter of dissolved solids.\r\n\r\nThe MERAS model was calibrated by making manual changes to parameter values and examining residuals for hydraulic heads and streamflow. Additional calibration was achieved through alternate use of UCODE-2005 and PEST. Simulated heads were compared to 55,786 hydraulic-head measurements from 3,245 wells in the MERAS model area. Values of root mean square error between simulated and observed hydraulic heads of all observations ranged from 8.33 feet in 1919 to 47.65 feet in 1951, though only six root mean square error values are greater than 40 feet for the entire simulation period. Simulated streamflow generally is lower than measured streamflow for streams with streamflow less than 1,000 cubic feet per second, and greater than measured streamflow for streams with streamflow more than 1,000 cubic feet per second. Simulated streamflow is underpredicted for 18 observations and overpredicted for 10 observations in the model. These differences in streamflow illustrate the large uncertainty in model inputs such as predevelopment recharge, overland flow, pumpage (from stream and aquifer), precipitation, and observation weights.\r\n\r\nThe groundwater-flow budget indicates changes in flow into (inflows) and out of (outflows) the model area during the pregroundwater-irrigation period (pre-1870) to 2007. Total flow (sum of inflows or outflows) through the model ranged from about 600 million gallons per day prior to development to 18,197 million gallons per day near the end of the simulation. The pumpage from wells represents the largest outflow components with a net rate of 18,197 million gallons per day near the end of the model simulation in 2006. Groundwater outflows are offset primarily by inflow from aquifer storage and recharge.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20095172","usgsCitation":"Clark, B.R., and Hart, R.M., 2009, The Mississippi Embayment Regional Aquifer Study (MERAS): Documentation of a groundwater-flow model constructed to assess water availability in the Mississippi embayment: U.S. Geological Survey Scientific Investigations Report 2009-5172, v, 62 p., https://doi.org/10.3133/sir20095172.","productDescription":"v, 62 p.","onlineOnly":"Y","costCenters":[{"id":129,"text":"Arkansas Water Science Center","active":true,"usgs":true},{"id":24708,"text":"Lower Mississippi-Gulf Water Science Center","active":true,"usgs":true},{"id":38131,"text":"WMA - Office of Planning and Programming","active":true,"usgs":true}],"links":[{"id":125672,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2009_5172.jpg"},{"id":415941,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_87505.htm","linkFileType":{"id":5,"text":"html"}},{"id":13110,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2009/5172/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Alabama, Arkansas, Kentucky, Louisiana, Mississippi, Missouri, Tennessee","otherGeospatial":"Mississippi embayment","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -94.0456,\n 31.5\n ],\n [\n -94.0456,\n 37.1667\n ],\n [\n -87.4167,\n 37.1667\n ],\n [\n -87.4167,\n 31.5\n ],\n [\n -94.0456,\n 31.5\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ac8e4b07f02db67b8ef","contributors":{"authors":[{"text":"Clark, Brian R. 0000-0001-6611-3807 brclark@usgs.gov","orcid":"https://orcid.org/0000-0001-6611-3807","contributorId":1502,"corporation":false,"usgs":true,"family":"Clark","given":"Brian","email":"brclark@usgs.gov","middleInitial":"R.","affiliations":[{"id":38131,"text":"WMA - Office of Planning and Programming","active":true,"usgs":true}],"preferred":true,"id":303636,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hart, Rheannon M. 0000-0003-4657-5945 rmhart@usgs.gov","orcid":"https://orcid.org/0000-0003-4657-5945","contributorId":5516,"corporation":false,"usgs":true,"family":"Hart","given":"Rheannon","email":"rmhart@usgs.gov","middleInitial":"M.","affiliations":[{"id":24708,"text":"Lower Mississippi-Gulf Water Science Center","active":true,"usgs":true},{"id":129,"text":"Arkansas Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303637,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":97898,"text":"tm4F2 - 2009 - AnalyzeHOLE - An Integrated Wellbore Flow Analysis Tool","interactions":[],"lastModifiedDate":"2012-02-02T00:15:03","indexId":"tm4F2","displayToPublicDate":"2009-10-03T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":335,"text":"Techniques and Methods","code":"TM","onlineIssn":"2328-7055","printIssn":"2328-7047","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"4-F2","title":"AnalyzeHOLE - An Integrated Wellbore Flow Analysis Tool","docAbstract":"Conventional interpretation of flow logs assumes that hydraulic conductivity is directly proportional to flow change with depth. However, well construction can significantly alter the expected relation between changes in fluid velocity and hydraulic conductivity. Strong hydraulic conductivity contrasts between lithologic intervals can be masked in continuously screened wells. Alternating intervals of screen and blank casing also can greatly complicate the relation between flow and hydraulic properties. More permeable units are not necessarily associated with rapid fluid-velocity increases. Thin, highly permeable units can be misinterpreted as thick and less permeable intervals or not identified at all. These conditions compromise standard flow-log interpretation because vertical flow fields are induced near the wellbore.\r\n\r\nAnalyzeHOLE, an integrated wellbore analysis tool for simulating flow and transport in wells and aquifer systems, provides a better alternative for simulating and evaluating complex well-aquifer system interaction. A pumping well and adjacent aquifer system are simulated with an axisymmetric, radial geometry in a two-dimensional MODFLOW model. Hydraulic conductivities are distributed by depth and estimated with PEST by minimizing squared differences between simulated and measured flows and drawdowns. Hydraulic conductivity can vary within a lithology but variance is limited with regularization. Transmissivity of the simulated system also can be constrained to estimates from single-well, pumping tests. Water-quality changes in the pumping well are simulated with simple mixing models between zones of differing water quality. These zones are differentiated by backtracking thousands of particles from the well screens with MODPATH. An Excel spreadsheet is used to interface the various components of AnalyzeHOLE by (1) creating model input files, (2) executing MODFLOW, MODPATH, PEST, and supporting FORTRAN routines, and (3) importing and graphically displaying pertinent results.","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Chapter 2 of Section F, Groundwater, Book 4, Hydrologic Analysis and Interpretation","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/tm4F2","usgsCitation":"Halford, K., 2009, AnalyzeHOLE - An Integrated Wellbore Flow Analysis Tool: U.S. Geological Survey Techniques and Methods 4-F2, Report: viii, 47 p.; Application Files (ZIP), https://doi.org/10.3133/tm4F2.","productDescription":"Report: viii, 47 p.; Application Files (ZIP)","onlineOnly":"N","additionalOnlineFiles":"Y","costCenters":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":118604,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/tm_4_f2.jpg"},{"id":13072,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/tm/tm4f2/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ac9e4b07f02db67c36f","contributors":{"authors":[{"text":"Halford, Keith 0000-0002-7322-1846","orcid":"https://orcid.org/0000-0002-7322-1846","contributorId":74845,"corporation":false,"usgs":true,"family":"Halford","given":"Keith","affiliations":[],"preferred":false,"id":303528,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":97852,"text":"sir20095183 - 2009 - Description and evaluation of numerical groundwater flow models for the Edwards Aquifer, south-central Texas","interactions":[],"lastModifiedDate":"2020-05-28T11:55:07.948529","indexId":"sir20095183","displayToPublicDate":"2009-09-29T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-5183","displayTitle":"Description and Evaluation of Numerical Groundwater Flow Models for the Edwards Aquifer, South-Central Texas","title":"Description and evaluation of numerical groundwater flow models for the Edwards Aquifer, south-central Texas","docAbstract":"A substantial number of public water system wells in south-central Texas withdraw groundwater from the karstic, highly productive Edwards aquifer. However, the use of numerical groundwater flow models to aid in the delineation of contributing areas for public water system wells in the Edwards aquifer is problematic because of the complex hydrogeologic framework and the presence of conduit-dominated flow paths in the aquifer. The U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality, evaluated six published numerical groundwater flow models (all deterministic) that have been developed for the Edwards aquifer San Antonio segment or Barton Springs segment, or both. This report describes the models developed and evaluates each with respect to accessibility and ease of use, range of conditions simulated, accuracy of simulations, agreement with dye-tracer tests, and limitations of the models. These models are (1) GWSIM model of the San Antonio segment, a FORTRAN computer-model code that pre-dates the development of MODFLOW; (2) MODFLOW conduit-flow model of San Antonio and Barton Springs segments; (3) MODFLOW diffuse-flow model of San Antonio and Barton Springs segments; (4) MODFLOW Groundwater Availability Modeling [GAM] model of the Barton Springs segment; (5) MODFLOW recalibrated GAM model of the Barton Springs segment; and (6) MODFLOW–DCM (dual conductivity model) conduit model of the Barton Springs segment. The GWSIM model code is not commercially available, is limited in its application to the San Antonio segment of the Edwards aquifer, and lacks the ability of MODFLOW to easily incorporate newly developed processes and packages to better simulate hydrologic processes. MODFLOW is a widely used and tested code for numerical modeling of groundwater flow, is well documented, and is in the public domain. These attributes make MODFLOW a preferred code with regard to accessibility and ease of use. The MODFLOW conduit-flow model incorporates improvements over previous models by using (1) a user-friendly interface, (2) updated computer codes (MODFLOW–96 and MODFLOW–2000), (3) a finer grid resolution, (4) less-restrictive boundary conditions, (5) an improved discretization of hydraulic conductivity, (6) more accurate estimates of pumping stresses, (7) a long transient simulation period (54 years, 1947–2000), and (8) a refined representation of high-permeability zones or conduits. All of the models except the MODFLOW–DCM conduit model have limitations resulting from the use of Darcy’s law to simulate groundwater flow in a karst aquifer system where non-Darcian, turbulent flow might actually dominate. The MODFLOW–DCM conduit model is an improvement in the ability to simulate karst-like flow conditions in conjunction with porous-media-type matrix flow. However, the MODFLOW–DCM conduit model has had limited application and testing and currently (2008) lacks commercially available pre- and post-processors. The MODFLOW conduit-flow and diffuse-flow Edwards aquifer models are limited by the lack of calibration for the northern part of the Barton Springs segment (Travis County) and their reliance on the use of the calibrated hydraulic conductivity and storativity values from the calibrated Barton Springs segment GAM model. The major limitation of the Barton Springs segment GAM and recalibrated GAM models is that they were calibrated to match measured water levels and springflows for a restrictive range of hydrologic conditions, with each model having different hydraulic conductivity and storativity values appropriate to the hydrologic conditions that were simulated. The need for two different sets of hydraulic conductivity and storativity values increases the uncertainty associated with the accuracy of either set of values, illustrates the non-uniqueness of the model solution, and probably most importantly demonstrates the limitations of using a one-layer model to represent the heterogeneous hydrostratigraphic units composing the Edwards aquifer. In general, the best matches or agreement between groundwater flow directions inferred by numerical model simulation, and by dye-tracer tests, are observed where model outputs accurately reproduce the configuration of the potentiometric surface with regard to the positions of major and minor groundwater troughs and divides. None of the models, with the possible exception of the MODFLOW–DCM conduit model, has a documented capability to accurately simulate travel times for conduit-dominated velocities in the Edwards aquifer. Public water system assessments of wells in the Barton Springs segment of the Edwards aquifer, and elsewhere where conduit-flow conditions are thought to dominate aquifer hydraulic behavior, might be enhanced by use of either the MODFLOW–DCM model or the newly developed U.S. Geological Survey MODFLOW Conduit-Flow Process module for MODFLOW–2005, because each incorporates a type of dual or triple hydraulic conductivity approach and has the capability to explicitly simulate turbulent flow and conduit hydraulic characteristics. |
To assess the effect that increased water use is having on the long-term availability of groundwater within the Ozark Plateaus aquifer system, a groundwater-flow model was developed using MODFLOW 2000 for a model area covering 7,340 square miles for parts of Arkansas, Kansas, Missouri, and Oklahoma. Vertically the model is divided into five units. From top to bottom these units of variable thickness are: the Western Interior Plains confining unit, the Springfield Plateau aquifer, the Ozark confining unit, the Ozark aquifer, and the St. Francois confining unit. Large mined zones contained within the Springfield Plateau aquifer are represented in the model as extensive voids with orders-of-magnitude larger hydraulic conductivity than the adjacent nonmined zones. Water-use data were compiled for the period 1960 to 2006, with the most complete data sets available for the period 1985 to 2006. In 2006, total water use from the Ozark aquifer for Missouri was 87 percent (8,531,520 cubic feet per day) of the total pumped from the Ozark aquifer, with Kansas at 7 percent (727,452 cubic feet per day), and Oklahoma at 6 percent (551,408 cubic feet per day); water use for Arkansas within the model area was minor. Water use in the model from the Springfield Plateau aquifer in 2005 was specified from reported and estimated values as 569,047 cubic feet per day. Calibration of the model was made against average water-level altitudes in the Ozark aquifer for the period 1980 to 1989 and against waterlevel altitudes obtained in 2006 for the Springfield Plateau and Ozark aquifers. Error in simulating water-level altitudes was largest where water-level altitude gradients were largest, particularly near large cones of depression. Groundwater flow within the model area occurs generally from the highlands of the Springfield Plateau in southwestern Missouri toward the west, with localized flow occurring towards rivers and pumping centers including the five largest pumping centers near Joplin, Missouri; Carthage, Missouri; Noel, Missouri; Pittsburg, Kansas; and Miami, Oklahoma.
Hypothetical scenarios involving various increases in groundwater-pumping rates were analyzed with the calibrated groundwater-flow model to assess changes in the flow system from 2007 to the year 2057. Pumping rates were increased between 0 and 4 percent per year starting with the 2006 rates for all wells in the model. Sustained pumping at 2006 rates was feasible at the five pumping centers until 2057; however, increases in pumping resulted in dewatering the aquifer and thus pumpage increases were not sustainable in Carthage and Noel for the 1 percent per year pumpage increase and greater hypothetical scenarios, and in Joplin and Miami for the 4 percent per year pumpage increase hypothetical scenarios.
Zone-budget analyses were performed to assess the groundwater flow into and out of three zones specified within the Ozark-aquifer layer of the model. The three zones represented the model part of the Ozark aquifer in Kansas (zone 1), Oklahoma (zone 2), and Missouri and Arkansas (zone 3). Groundwater pumping causes substantial reductions in water in storage and induces flow through the Ozark confining unit for all hypothetical scenarios evaluated. Net simulated flow in 2057 from Kansas (zone 1) to Missouri (zone 3) ranges from 74,044 cubic feet per day for 2006 pumping rates (hypothetical scenario 1) to 625,319 cubic feet per day for a 4 percent increase in pumping per year (hypothetical scenario 5). Pumping from wells completed in the Ozark aquifer is the largest component of flow out of zone 3 in Missouri and Arkansas, and varies between 88 to 91 percent of the total flow out of zone 3 for all of the hypothetical scenarios. The largest component of flow into Oklahoma (zone 2) comes from the overlying Ozark confining unit, which is consistently about 45 percent of the total. Flow from the release of water in storage, from general-head boundaries, and from zones 1 and 3 is considerably smaller values that range from 3 to 22 percent of the total flow into zone 2. The largest flow out of the Oklahoma part of the model occurs from pumping from wells and ranges from 52 to 69 percent of the total.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/sir20095148","isbn":"9781411325142","collaboration":"Prepared in cooperation with the Kansas Water Office","usgsCitation":"Czarnecki, J.B., Gillip, J.A., Jones, P.M., and Yeatts, D.S., 2009, Groundwater-flow model of the Ozark Plateaus aquifer system, northwestern Arkansas, southeastern Kansas, southwestern Missouri, and northeastern Oklahoma: U.S. Geological Survey Scientific Investigations Report 2009-5148, vi, 62 p., https://doi.org/10.3133/sir20095148.","productDescription":"vi, 62 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":129,"text":"Arkansas Water Science Center","active":true,"usgs":true}],"links":[{"id":125613,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2009_5148.jpg"},{"id":12955,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2009/5148/","linkFileType":{"id":5,"text":"html"}},{"id":345245,"rank":3,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2009/5148/pdf/SIR2009-5148.pdf","text":"Report","size":"14 MB","linkFileType":{"id":1,"text":"pdf"},"description":"Report"}],"country":"United States","state":"Arkansas, Kansas, Missouri, Oklahoma","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -90.703125,\n 38.634036452919226\n ],\n [\n -91.263427734375,\n 38.59970036588819\n ],\n [\n -92.63671875,\n 38.50519140240356\n ],\n [\n -93.3837890625,\n 38.30718056188316\n ],\n [\n -94.04296874999999,\n 38.09133660751176\n ],\n [\n -94.844970703125,\n 37.86618078529668\n ],\n [\n -95.2294921875,\n 37.46613860234406\n ],\n [\n -95.43823242187499,\n 37.15156050223665\n ],\n [\n -95.55908203125,\n 36.474306755095235\n ],\n [\n -95.49316406249999,\n 36.06686213257888\n ],\n [\n -95.16357421875,\n 35.71975793933433\n ],\n [\n -94.141845703125,\n 35.79108281624994\n ],\n [\n -91.7578125,\n 35.77325759103725\n ],\n [\n -91.01074218749999,\n 35.92464453144099\n ],\n [\n -90.582275390625,\n 36.34167804918315\n ],\n [\n -90.41748046874999,\n 36.80048816579081\n ],\n [\n -90.46142578125,\n 37.09023980307208\n ],\n [\n -90.3955078125,\n 37.61423141542417\n ],\n [\n -90.384521484375,\n 38.108627664321276\n ],\n [\n -90.384521484375,\n 38.41055825094609\n ],\n [\n -90.3955078125,\n 38.61687046392973\n ],\n [\n -90.703125,\n 38.634036452919226\n ]\n ]\n ]\n }\n }\n ]\n}","tableOfContents":"Twarakavi et al (2008) compared four packages that can be used to estimate recharge for regional-scale groundwater flow simulations using MODFLOW (Harbaugh, 2005). This comment is focused on the comparisons made between two of these packages, namely, UZF1 (Niswonger et al., 2006) and a derivative of HYDRUS referred to herein as HYDRUS (Seo et al., 2007). In their paper, Twarakavi et al. (2008) stated that HYDRUS more accurately simulates unsaturated flow processes and groundwater recharge as compared to UZF1. However, Twarakavi et al. (2008) did not address several important differences between these models that undermine the advantages of HYDRUS as compared to UZF1 for simulating recharge. These differences were not revealed by the comparisons presented by Twarakavi et al. because the test simulations used to compare the models were too simple
","language":"English","publisher":"Soil Science Society","doi":"10.2136/vzj2008.0155","usgsCitation":"Niswonger, R., and Prudic, D.E., 2009, Comment on \"Evaluating interactions between groundwater and vadose zone using the HYDRUS-based flow package for MODFLOW\" by Navin Kumar C. Twarakavi, Jirka Šimůnek and Sophia Seo: Vadose Zone Journal, v. 8, no. 3, p. 818-819, https://doi.org/10.2136/vzj2008.0155.","productDescription":"2 p.","startPage":"818","endPage":"819","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":245691,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f7e6e4b0c8380cd4cd75","contributors":{"authors":[{"text":"Niswonger, R.G.","contributorId":103393,"corporation":false,"usgs":true,"family":"Niswonger","given":"R.G.","affiliations":[],"preferred":false,"id":456728,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Prudic, David E. deprudic@usgs.gov","contributorId":3430,"corporation":false,"usgs":true,"family":"Prudic","given":"David","email":"deprudic@usgs.gov","middleInitial":"E.","affiliations":[{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true}],"preferred":true,"id":456727,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70000040,"text":"70000040 - 2008 - Coupled semivariogram uncertainty of hydrogeological and geophysical data on capture zone uncertainty analysis","interactions":[],"lastModifiedDate":"2012-03-08T17:16:35","indexId":"70000040","displayToPublicDate":"2010-09-28T23:11:19","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2341,"text":"Journal of Hydrologic Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Coupled semivariogram uncertainty of hydrogeological and geophysical data on capture zone uncertainty analysis","docAbstract":"This study investigates capture zone uncertainty that relates to the coupled semivariogram uncertainty of hydrogeological and geophysical data. Semivariogram uncertainty is represented by the uncertainty in structural parameters (range, sill, and nugget). We used the beta distribution function to derive the prior distributions of structural parameters. The probability distributions of structural parameters were further updated through the Bayesian approach with the Gaussian likelihood functions. Cokriging of noncollocated pumping test data and electrical resistivity data was conducted to better estimate hydraulic conductivity through autosemivariograms and pseudo-cross-semivariogram. Sensitivities of capture zone variability with respect to the spatial variability of hydraulic conductivity, porosity and aquifer thickness were analyzed using ANOVA. The proposed methodology was applied to the analysis of capture zone uncertainty at the Chicot aquifer in Southwestern Louisiana, where a regional groundwater flow model was developed. MODFLOW-MODPATH was adopted to delineate the capture zone. The ANOVA results showed that both capture zone area and compactness were sensitive to hydraulic conductivity variation. We concluded that the capture zone uncertainty due to the semivariogram uncertainty is much higher than that due to the kriging uncertainty for given semivariograms. In other words, the sole use of conditional variances of kriging may greatly underestimate the flow response uncertainty. Semivariogram uncertainty should also be taken into account in the uncertainty analysis. ?? 2008 ASCE.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrologic Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1061/(ASCE)1084-0699(2008)13:10(915)","issn":"10840699","usgsCitation":"Rahman, A., Tsai, F., White, C., and Willson, C.S., 2008, Coupled semivariogram uncertainty of hydrogeological and geophysical data on capture zone uncertainty analysis: Journal of Hydrologic Engineering, v. 13, no. 10, p. 915-925, https://doi.org/10.1061/(ASCE)1084-0699(2008)13:10(915).","startPage":"915","endPage":"925","costCenters":[],"links":[{"id":203393,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":18643,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1061/(ASCE)1084-0699(2008)13:10(915)"}],"volume":"13","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b00e4b07f02db698385","contributors":{"authors":[{"text":"Rahman, A.","contributorId":93171,"corporation":false,"usgs":true,"family":"Rahman","given":"A.","email":"","affiliations":[],"preferred":false,"id":344751,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tsai, F.T.-C.","contributorId":28343,"corporation":false,"usgs":true,"family":"Tsai","given":"F.T.-C.","email":"","affiliations":[],"preferred":false,"id":344748,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"White, C.D.","contributorId":46664,"corporation":false,"usgs":true,"family":"White","given":"C.D.","email":"","affiliations":[],"preferred":false,"id":344749,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Willson, C. S.","contributorId":90440,"corporation":false,"usgs":false,"family":"Willson","given":"C.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":344750,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70000405,"text":"70000405 - 2008 - Modeling axisymmetric flow and transport","interactions":[],"lastModifiedDate":"2012-03-08T17:16:36","indexId":"70000405","displayToPublicDate":"2010-09-28T23:09:23","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Modeling axisymmetric flow and transport","docAbstract":"Unmodified versions of common computer programs such as MODFLOW, MT3DMS, and SEAWAT that use Cartesian geometry can accurately simulate axially symmetric ground water flow and solute transport. Axisymmetric flow and transport are simulated by adjusting several input parameters to account for the increase in flow area with radial distance from the injection or extraction well. Logarithmic weighting of interblock transmissivity, a standard option in MODFLOW, can be used for axisymmetric models to represent the linear change in hydraulic conductance within a single finite-difference cell. Results from three test problems (ground water extraction, an aquifer push-pull test, and upconing of saline water into an extraction well) show good agreement with analytical solutions or with results from other numerical models designed specifically to simulate the axisymmetric geometry. Axisymmetric models are not commonly used but can offer an efficient alternative to full three-dimensional models, provided the assumption of axial symmetry can be justified. For the upconing problem, the axisymmetric model was more than 1000 times faster than an equivalent three-dimensional model. Computational gains with the axisymmetric models may be useful for quickly determining appropriate levels of grid resolution for three-dimensional models and for estimating aquifer parameters from field tests.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ground Water","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1745-6584.2008.00445.x","issn":"17456584","usgsCitation":"Langevin, C., 2008, Modeling axisymmetric flow and transport: Ground Water, v. 46, no. 4, p. 579-590, https://doi.org/10.1111/j.1745-6584.2008.00445.x.","startPage":"579","endPage":"590","costCenters":[],"links":[{"id":203481,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":18836,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1745-6584.2008.00445.x"}],"volume":"46","issue":"4","noUsgsAuthors":false,"publicationDate":"2008-07-04","publicationStatus":"PW","scienceBaseUri":"4f4e4b05e4b07f02db6999a3","contributors":{"authors":[{"text":"Langevin, C.D.","contributorId":25976,"corporation":false,"usgs":true,"family":"Langevin","given":"C.D.","email":"","affiliations":[],"preferred":false,"id":345662,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70000144,"text":"70000144 - 2008 - Permeameter data verify new turbulence process for MODFLOW","interactions":[],"lastModifiedDate":"2015-03-26T11:32:32","indexId":"70000144","displayToPublicDate":"2010-09-28T23:09:22","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Permeameter data verify new turbulence process for MODFLOW","docAbstract":"A sample of Key Largo Limestone from southern Florida exhibited turbulent flow behavior along three orthogonal axes as reported in recently published permeameter experiments. The limestone sample was a cube measuring 0.2 m on edge. The published nonlinear relation between hydraulic gradient and discharge was simulated using the turbulent flow approximation applied in the Conduit Flow Process (CFP) for MODFLOW-2005 mode 2, CFPM2. The good agreement between the experimental data and the simulated results verifies the utility of the approach used to simulate the effects of turbulent flow on head distributions and flux in the CFPM2 module of MODFLOW-2005.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ground Water","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1745-6584.2008.00458.x","issn":"0017467X","usgsCitation":"Kuniansky, E.L., Halford, K.J., and Shoemaker, W., 2008, Permeameter data verify new turbulence process for MODFLOW: Ground Water, v. 46, no. 5, p. 768-771, https://doi.org/10.1111/j.1745-6584.2008.00458.x.","startPage":"768","endPage":"771","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":203720,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":18690,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1745-6584.2008.00458.x"}],"volume":"46","issue":"5","noUsgsAuthors":false,"publicationDate":"2008-08-25","publicationStatus":"PW","scienceBaseUri":"4f4e4ae1e4b07f02db6885a3","contributors":{"authors":[{"text":"Kuniansky, Eve L. 0000-0002-5581-0225 elkunian@usgs.gov","orcid":"https://orcid.org/0000-0002-5581-0225","contributorId":932,"corporation":false,"usgs":true,"family":"Kuniansky","given":"Eve","email":"elkunian@usgs.gov","middleInitial":"L.","affiliations":[{"id":509,"text":"Office of the Associate Director for Water","active":true,"usgs":true},{"id":5064,"text":"Southeast Regional Director's Office","active":true,"usgs":true}],"preferred":true,"id":344966,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Halford, Keith J. 0000-0002-7322-1846 khalford@usgs.gov","orcid":"https://orcid.org/0000-0002-7322-1846","contributorId":1374,"corporation":false,"usgs":true,"family":"Halford","given":"Keith","email":"khalford@usgs.gov","middleInitial":"J.","affiliations":[{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true}],"preferred":true,"id":344965,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shoemaker, W. Barclay bshoemak@usgs.gov","contributorId":1495,"corporation":false,"usgs":true,"family":"Shoemaker","given":"W. Barclay","email":"bshoemak@usgs.gov","affiliations":[{"id":156,"text":"Caribbean Water Science Center","active":true,"usgs":true},{"id":269,"text":"FLWSC-Ft. Lauderdale","active":true,"usgs":true}],"preferred":true,"id":344964,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":97337,"text":"tm6A27 - 2008 - User Guide for HUFPrint, A Tabulation and Visualization Utility for the Hydrogeologic-Unit Flow (HUF) Package of MODFLOW","interactions":[],"lastModifiedDate":"2012-03-02T17:16:07","indexId":"tm6A27","displayToPublicDate":"2009-02-28T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":335,"text":"Techniques and Methods","code":"TM","onlineIssn":"2328-7055","printIssn":"2328-7047","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"6-A27","title":"User Guide for HUFPrint, A Tabulation and Visualization Utility for the Hydrogeologic-Unit Flow (HUF) Package of MODFLOW","docAbstract":"This report documents HUFPrint, a computer program that extracts and displays information about model structure and hydraulic properties from the input data for a model built using the Hydrogeologic-Unit Flow (HUF) Package of the U.S. Geological Survey's MODFLOW program for modeling ground-water flow. HUFPrint reads the HUF Package and other MODFLOW input files, processes the data by hydrogeologic unit and by model layer, and generates text and graphics files useful for visualizing the data or for further processing. For hydrogeologic units, HUFPrint outputs such hydraulic properties as horizontal hydraulic conductivity along rows, horizontal hydraulic conductivity along columns, horizontal anisotropy, vertical hydraulic conductivity or anisotropy, specific storage, specific yield, and hydraulic-conductivity depth-dependence coefficient. For model layers, HUFPrint outputs such effective hydraulic properties as horizontal hydraulic conductivity along rows, horizontal hydraulic conductivity along columns, horizontal anisotropy, specific storage, primary direction of anisotropy, and vertical conductance. Text files tabulating hydraulic properties by hydrogeologic unit, by model layer, or in a specified vertical section may be generated. Graphics showing two-dimensional cross sections and one-dimensional vertical sections at specified locations also may be generated. HUFPrint reads input files designed for MODFLOW-2000 or MODFLOW-2005.","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Chapter 27 of Book 6. Modeling Techniques, Section A. Ground Water","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/tm6A27","isbn":"9781411323339","usgsCitation":"Banta, E., and Provost, A., 2008, User Guide for HUFPrint, A Tabulation and Visualization Utility for the Hydrogeologic-Unit Flow (HUF) Package of MODFLOW: U.S. Geological Survey Techniques and Methods 6-A27, vi, 13 p., https://doi.org/10.3133/tm6A27.","productDescription":"vi, 13 p.","costCenters":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"links":[{"id":122422,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/tm_6_a27.gif"},{"id":12391,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/tm/06A27/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a17e4b07f02db60419c","contributors":{"authors":[{"text":"Banta, Edward R.","contributorId":49820,"corporation":false,"usgs":true,"family":"Banta","given":"Edward R.","affiliations":[],"preferred":false,"id":301739,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Provost, Alden M.","contributorId":85652,"corporation":false,"usgs":true,"family":"Provost","given":"Alden M.","affiliations":[],"preferred":false,"id":301740,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":97273,"text":"sir20075257 - 2008 - Use of inverse-modeling methods to improve ground-water-model calibration and evaluate model-prediction uncertainty, Camp Edwards, Cape Cod, Massachusetts","interactions":[],"lastModifiedDate":"2019-08-20T12:31:33","indexId":"sir20075257","displayToPublicDate":"2009-02-07T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2007-5257","title":"Use of inverse-modeling methods to improve ground-water-model calibration and evaluate model-prediction uncertainty, Camp Edwards, Cape Cod, Massachusetts","docAbstract":"Historical weapons testing and disposal activities at Camp Edwards, which is located on the Massachusetts Military Reservation, western Cape Cod, have resulted in the release of contaminants into an underlying sand and gravel aquifer that is the sole source of potable water to surrounding communities. Ground-water models have been used at the site to simulate advective transport in the aquifer in support of field investigations. Reasonable models developed by different groups and calibrated by trial and error often yield different predictions of advective transport, and the predictions lack quantitative measures of uncertainty. A recently (2004) developed regional model of western Cape Cod, modified to include the sensitivity and parameter-estimation capabilities of MODFLOW-2000, was used in this report to evaluate the utility of inverse (statistical) methods to (1) improve model calibration and (2) assess model-prediction uncertainty.\r\n\r\nSimulated heads and flows were most sensitive to recharge and to the horizontal hydraulic conductivity of the Buzzards Bay and Sandwich Moraines and the Buzzards Bay and northern parts of the Mashpee outwash plains. Conversely, simulated heads and flows were much less sensitive to vertical hydraulic conductivity. Parameter estimation (inverse calibration) improved the match to observed heads and flows; the absolute mean residual for heads improved by 0.32 feet and the absolute mean residual for streamflows improved by about 0.2 cubic feet per second. Advective-transport predictions in Camp Edwards generally were most sensitive to the parameters with the highest precision (lowest coefficients of variation), indicating that the numerical model is adequate for evaluating prediction uncertainties in and around Camp Edwards. The incorporation of an advective-transport observation, representing the leading edge of a contaminant plume that had been difficult to match by using trial-and-error calibration, improved the match between an observed and simulated plume path; however, a modified representation of local geology was needed to simultaneously maintain a reasonable calibration to heads and flows and to the plume path.\r\n\r\nAdvective-transport uncertainties were expressed as about 68-, 95-, and 99-percent confidence intervals on three dimensional simulated particle positions. The confidence intervals can be graphically represented as ellipses around individual particle positions in the X-Y (geographic) plane and in the X-Z or Y-Z (vertical) planes. The merging of individual ellipses allows uncertainties on forward particle tracks to be displayed in map or cross-sectional view as a cone of uncertainty around a simulated particle path; uncertainties on reverse particle-track endpoints - representing simulated recharge locations - can be geographically displayed as areas at the water table around the discrete particle endpoints. This information gives decisionmakers insight into the level of confidence they can have in particle-tracking results and can assist them in the efficient use of available field resources.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20075257","collaboration":"Prepared in cooperation with the Impact Area Groundwater Study Program of the National Guard Bureau and U.S. Army Environmental Command","usgsCitation":"Walter, D.A., and LeBlanc, D.R., 2008, Use of inverse-modeling methods to improve ground-water-model calibration and evaluate model-prediction uncertainty, Camp Edwards, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Report 2007-5257, viii, 49 p., https://doi.org/10.3133/sir20075257.","productDescription":"viii, 49 p.","costCenters":[{"id":377,"text":"Massachusetts-Rhode Island Water Science Center","active":false,"usgs":true},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":125651,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2007_5257.jpg"},{"id":12323,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2007/5257/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Massachusetts","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -70.71666666666667,41.46666666666667 ], [ -70.71666666666667,41.8 ], [ -70.11666666666666,41.8 ], [ -70.11666666666666,41.46666666666667 ], [ -70.71666666666667,41.46666666666667 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a18e4b07f02db60519c","contributors":{"authors":[{"text":"Walter, Donald A. 0000-0003-0879-4477 dawalter@usgs.gov","orcid":"https://orcid.org/0000-0003-0879-4477","contributorId":1101,"corporation":false,"usgs":true,"family":"Walter","given":"Donald","email":"dawalter@usgs.gov","middleInitial":"A.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":301551,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"LeBlanc, Denis R. 0000-0002-4646-2628 dleblanc@usgs.gov","orcid":"https://orcid.org/0000-0002-4646-2628","contributorId":1696,"corporation":false,"usgs":true,"family":"LeBlanc","given":"Denis","email":"dleblanc@usgs.gov","middleInitial":"R.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":301552,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}