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USGS2003

Methodology for estimating times of remediation associated with monitored natural attenuation

Natural attenuation processes combine to disperse, immobilize, and biologically transform anthropogenic contaminants, such as petroleum hydrocarbons and chlorinated ethenes, in ground-water systems. The time required for these processes to lower contaminant concentrations to levels protective of human health and the environment, however, varies widely between different hydrologic systems, different chemical contaminants, and varying amounts of contaminants. This report outlines a method for estimating timeframes required for natural attenuation processes, such as dispersion, sorption, and biodegradation, to lower contaminant concentrations and mass to predetermined regulatory goals in groundwater systems. The time-of-remediation (TOR) problem described in this report is formulated as three interactive components: (1) estimating the length of a contaminant plume once it has achieved a steady-state configuration from a source area of constant contaminant concentration, (2) estimating the time required for a plume to shrink to a smaller, regulatoryacceptable configuration when source-area contaminant concentrations are lowered by engineered methods, and (3) estimating the time needed for nonaqueous phase liquid (NAPL) contaminants to dissolve, disperse, and biodegrade below predetermined levels in contaminant source areas. This conceptualization was used to develop Natural Attenuation Software (NAS), an interactive computer aquifers. NAS was designed as a screening tool and requires the input of detailed site information about hydrogeology, redox conditions, and the distribution of contaminants. Because NAS is based on numerous simplifications of hydrologic, microbial, and geochemical processes, the program may introduce unacceptable errors for highly heterogeneous hydrologic systems. In such cases, application of the TOR framework outlined in this report may require more detailed, site-specific digital modeling. The NAS software may be downloaded from the Web site http://www.cee.vt.edu/NAS/ Application of NAS illustrates several general characteristics shared by all TOR problems. First, the distance of stabilization of a contaminant plume is strongly dependent on the natural attenuation capacity of particular ground-water systems. The time that it takes a plume to reach a steady-state configuration, however, is independent of natural attenuation capacity. Rather, the time of stabilization is most strongly affected by the sorptive capacity of the aquifer, which is dependent on the organic matter content of the aquifer sediments, as well as the sorptive properties of individual contaminants. As a general rule, a high sorptive capacity retards a plume.s growth or shrinkage, and increases the time of stabilization. Finally, the time of NAPL dissolution depends largely on NAPL mass, composition, geometry, and hydrologic factors, such as ground-water flow rates. An example TOR analysis for petroleum hydrocarbon NAPL was performed for the Laurel Bay site in South Carolina. About 500 to 1,000 pounds of gasoline leaked into the aquifer at this site in 1991, and the NAS simulations suggested that TOR would be on the order of 10 years for soluble and poorly sorbed compounds, such as benzene and methyl tertiary-butyl ether (MTBE). Conversely, TOR would be on the order of 40 years for less soluble, more strongly sorbed compounds, such as toluene, ethylbenzene, and xylenes (TEX). These TOR estimates are roughly consistent with contaminant concentrations observed over 10 years of monitoring at this site where benzene and MTBE concentrations were observed to decrease rapidly and are approaching regulatory maximum concentration limits, whereas toluene, ethylbenzene, and xylene concentrations decreased at a slower rate and have remained relatively high. An example TOR analysis for petroleum hydrocarbon NAPL was performed for the Laurel Bay site in South Carolina.

South Carolina↗
USGS1982

Evaluation of a predictive ground-water solute-transport model at the Idaho National Engineering Laboratory, Idaho

Aqueous chemical and radioactive wastes discharged to shallow ponds and to shallow or deep wells on the Idaho National Engineering Laboratory (INEL) since 1952 have affected the quality of the ground water in the underlying Snake River Plain aquifer. The aqueous wastes have created large and laterally dispersed concentration plumes within the aquifer. The waste plumes with the largest areal distribution are those of chloride, tritium, and with high specific conductance values. The data from eight wells drilled near the southern INEL boundary during the summer of 1980 were used to evaluate the accuracy of a predictive modeling study completed in 1973, and to simulate 1980 positions of chloride and tritium plumes. Data interpretation from the drilling program indicates that the hydrogeologic characteristics of the subsurface rocks have marked effects on the regional ground-water flow regimen and, therefore, the movement of aqueous wastes. As expected, the waste plumes projected by the computer model for 1980, extended somewhat further downgradient than indicated by well data due to conservative worst-case assumptions in the model input and inaccurate approximations of subsequent waste discharge and aquifer recharge conditions. (USGS)

Idaho↗
USGS1995

Deposition and simulation of sediment transport in the Lower Susquehanna River reservoir system

The Susquehanna River drains 27,510 square miles in New York, Pennsylvania, and Maryland and is the largest tributary to the Chesapeake Bay. Three large hydroelectric dams are located on the river, Safe Harbor (Lake Clarke) and Holtwood (Lake Aldred) in southern Pennsylvania, and Conowingo (Conowingo Reservoir) in northern Maryland. About 259 million tons of sediment have been deposited in the three reservoirs. Lake Clarke contains about 90.7 million tons of sediment, Lake Aldred contains about 13.6 million tons, and Conowingo Reservoir contains about 155 million tons. An estimated 64.8 million tons of sand, 19.7 million tons of coal, 112 million tons of silt, and 63.3 million tons of clay are deposited in the three reservoirs. Deposition in the reservoirs is variable and ranges from 0 to 30 feet. Chemical analyses of sediment core samples indicate that the three reservoirs combined contain about 814,000 tons of organic nitrogen, 98,900 tons of ammonia as nitrogen, 226,000 tons of phosphorus, 5,610,000 1tons of iron, 2,250,000 tons of aluminum, and about 409,000 tons of manganese. Historical data indicate that Lake Clarke and Lake Aldred have reached equilibrium, and that they no longer store sediment. A comparison of cross-sectional data from Lake Clarke and Lake Aldred with data from Conowingo Reservoir indicates that Conowingo Reservoir will reach equilibrium within the next 20 to 30 years. As the Conowingo Reservoir fills with sediment and approaches equilibrium, the amount of sediment transported to the Chesapeake Bay will increase. The most notable increases will take place when very high flows scour the deposited sediment. Sediment transport through the reservoir system was simulated with the U.S. Army Corps of Engineers' HEC-6 computer model. The model was calibrated with monthly sediment loads for calendar year 1987. Calibration runs with options set for maximum trap efficiency and a "natural" particle-size distribution resulted in an overall computed trap efficiency of 34 percent for 1987, much less than the measured efficiency of 71 percent.

Water-Resources Investigations Report↗
USGS1975

Water resources data for Maine, water year 1974

Water resources data for the 1974 water year for Maine including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, records of water-quality data on the chemical and physical characteristics of surface- and ground-water, and records of ground-water levels in index wells are given in this report. In Part 1, records are included for 63 gaging stations, of which 62 are streamflow discharge stations, and 1 is a lake station; also are included records for 22 crest-stage partial-record stations, and 14 miscellaneous sites. In Part 2, water quality data on chemical, physical, and biological characteristics of surface and ground water were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 60minute intervals. Records are given for 38 sampling stations of which 11 are continuous record stations, and 27 are miscellaneous sites. Records of chemical analyses are also given for 21 ground-water sites. In Part 3, water level data are shown for 11 ground-water wells. Locations of surface-water stations, water-quality stations, and ground-water wells are shown in figure 2. A few pertinent stations in bordering States and Provinces are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of G. S. Hayes, District Chief, succeeded by C. R. Wagner. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Maine.

Maine↗
USGS1974

Water resources data for Mississippi, water year 1973

Water resources data for the 1973 water year for Mississippi including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 79 gaging stations of which 75 are streamflow discharge stations, and 4 are reservoir or lake stations; also are included records for 58 low-flow partial-record stations, 139 crest-stage partial-record stations, and 79 miscellaneous sites. Locations of gaging stations are shown in Figure 1. In Part 2, data on the quality of surface water (chemical and temperature) were collected from designated sampling sites at predetermined intervals such as monthly, or less frequently. Records are given for 70 sampling stations of which 32 are continuous record stations, 26 are partial-record stations, and 12 are miscellaneous sites. Locations of water-quality stations are shown in Figure 1. A few pertinent stations (not included above) furnished by bordering States are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of L. E. Carroon, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Mississippi.

Mississippi↗
USGS1975

Water resources data for Iowa, water year 1974; Part II, Water quality records

Water resources data for the 1974 water year for Iowa including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface and ground water, are given in this report. In Part 1, records are included for 127 gaging stations of which 119 are streamflow discharge stations, and 8 are reservoir or lake stations; also included are records for 426 low-flow partial-record stations, 128 crest-stage partial-record stations, and 30 miscellaneous sites. Locations of gaging stations are shown in Figure 2. In Part 2, water quality data on chemical, physical, biological, and sediment characteristics of surface water were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently. Records are given for 353 sampling stations of which 23 are continuous record stations, 9 are partial-record stations, and 321 are miscellaneous sites. Locations of water-quality stations are shown in Figure 3. A summary of periodic water temperature data is given for 98 regular gaging stations. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of S.W. Wiitala, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Iowa.

Iowa↗
USGS1973

Water resources data for Missouri, water year 1972

Water resources data for the 1972 water year for Missouri including records of streamflow or lake storage at gaging stations, partial-record stations, and selected springs, and records of water-quality data on the chemical and physical characteristics of surface and ground water, are given in this report. In Part 1, records are included for 157 gaging stations of which 150 are streamflow discharge stations, and 7 are lake stations; also are included records for 104 crest-stage partial-record stations. Locations of gaging stations are shown in Figure 1. In Part 2, data on the quality of surface water (chemical, temperature, and sediment) were collected from designated sampling sites at predetermined intervals such as weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 30-, or 60-minute intervals. Records are given for 84 sampling stations of which 25 are partial-record stations and 5 are miscellaneous sites. Locations of water-quality stations are shown in Figure 2. A few pertinent stations (not included above) in bordering States are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Anthony Homyk, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Missouri.

Missouri↗
USGS1975

Water resources data for Mississippi, water year 1974

Water resources data for the 1974 water year for Mississippi including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, special information on the flood in south-central Mississippi in April, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 79 gaging stations of which 75 are streamflow discharge stations, and 4 are reservoir or lake stations; also are included records for 11 low-flow partial-record stations, 136 crest-stage partial-record stations, and 149 miscellaneous sites. Locations of continuous-record gaging stations are shown in figure 1 and locations of partial-record stations are shown in figure 2. In Part 2, water-quality data on chemical, physical, and biological characteristics of surface water are included for designated sampling sites at which samples were obtained at predetermined intervals such as daily, weekly, monthly, or less frequently. Records are given for 70 sampling stations of which 32 are continuous-record stations, 26 are partial-record stations, and 12 are miscellaneous sites. Locations of water-quality stations are shown in figure 1. A few pertinent stations (not included above) furnished by bordering States are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of L. E. Carroon, district chief. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Mississippi.

Mississippi↗
USGS1972

Water resources data for Mississippi, water year 1971

Water resources data for the 1971 water year for Mississippi including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 71 gaging stations of which 67 are streamflow discharge stations, and 4 are reservoir or lake stations; also are included records for 27 low-flow partial-record stations, 143 crest-stage partial-record stations, and 91 miscellaneous sites. Locations of gaging stations are shown in Figure 1. In Part 2, data on the quality of surface water (chemical and temperature) were collected from designated sampling sites at pre-determined intervals such as monthly, or less frequently, and at one site data were recorded on punched paper tape at 60-minute intervals. Records are given for 55 sampling stations of which 5 are continuous record stations, 26 are partial-record stations, and 3 are miscellaneous sites. Locations of water-quality stations are shown in Figure 1. A few pertinent stations (not included above) in bordering States are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of L. E. Carroon, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Mississippi.

Mississippi↗
USGS1975

Water resources data for Louisiana, water year 1974

Water resources data for the 1974 water year for Louisiana including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 355 gaging stations of which 74 are streamflow discharge stations, 8 are stage only streamflow stations, and 11 are reservoir or lake stations; also are included records for 110 flood-profile partial-record stations, 83 crest-stage partial-record stations, and 69 miscellaneous sites Locations of continuous-record gaging stations are shown in figure 1 and locations of crest-stage partial-record stations are shown in figure 2. In Part 2, water-quality data on chemical, physical, and biological characteristics of surface water were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 15- or 60-minute intervals. Records are given for sampling stations of which 12 are continuous-record stations, 50 are partial-record stations, and 103 are miscellaneous sites. Locations of water-quality stations are shown in figure 3. A few pertinent stations in bordering States are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Albert N. Cameron, district chief. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

Louisiana↗
USGS1975

Water resources data for Missouri, water year 1974

Water resources data for the 1974 water year for Missouri including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 144 gaging stations of which 137 are streamflow discharge stations, and 7 are reservoir or lake stations; also included are records for 105 crest-stage partial-record stations, and miscellaneous sites. Locations of gaging stations are shown in figure1. In Part 2, water-quality data on chemical, physical, and biological characteristics of surface water were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 15-, 30-, or 60-minute intervals. Records are given for 108 sampling stations of which 53 are continuous record stations, 30 are partial-record stations, and 25 are miscellaneous sampling sites. Locations of water-quality stations are shown in figure 1. A few pertinent stations in bordering states are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Anthony Homyk, district chief. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Missouri.

Missouri↗
USGS1972

Water resources data for West Virginia, water year 1971; Part 1. Surface water records; Part 2. Water quality records

Water resources data for the 1971 water year for West Virginia including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 111 gaging stations of which 105 are streamflow discharge stations, 1 is stage only streamflow station, and 5 are reservoir or lake stations; also included are records for 5 low-flow partial-record stations, 44 crest-stage partial-record stations, and 6 miscellaneous sites. Locations of gaging stations are shown in Figure 1. In Part 2, data on the quality of surface water (chemical, temperature, and sediment) were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorder on punched paper tape at 15-, 30-, or 60-minute intervals. Records are given for 23 sampling stations of which 10 are continuous record stations, 11 are partial-record stations, and 2 are miscellaneous sites. Locations of water-quality stations are shown in Figure 1. A few pertinent stations (not included above) in bordering States are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Edwin E. Harris, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in West Virginia.

West Virginia↗
USGS1983

Projected effects of proposed chloride-control projects on shallow ground water– Preliminary results for the Wichita River basin, Texas

The U.S. Army Corps of Engineers' plan to control the natural chloride pollution in the Wichita River basin includes the construction of Truscott Brine Lake on a tributary of the North Wichita River. In connection with the proposed brine lake, the U.S. Geological Survey was requested to: (1) Define the existing ground-water conditions in the shallow fresh-water system of the project area; and (2) project the post-construction effects of the proposed lake on the fresh-water aquifer, especially in relation to hydraulic-head changes but also with respect to possible changes in the chemical quality of the ground water. The fresh-water aquifer in the project area is a shallow water-table system with relatively fresh water (generally a calcium sulfate type) that contains approximately 500 to 5,000 milligrams per liter of dissolved solids. The aquifer consists of Permian rocks with very small values of hydraulic conductivity and overlies a brine system (sodium chloride type) that is even less permeable. A thin transition zone separates the fresh-water aquifer and the brine system. Small quantities of infiltration from precipitation throughout the area's watershed constitute the recharge to the aquifer. Discharge from the aquifer consists of the small base flow along creeks; well discharge is negligible. Two-dimensional mathematical computer models were developed for aquifer simulation of: (1) Steady-state conditions in a fresh-water system and (2) transient conditions in a brine- fresh-water system where the density effects of the brine are considered. The main results 'of projecting the effects of the proposed Truscott Brine Lake on the fresh-water aquifer are: (1) Hydraulic head rises of 5 to 40 feet would be confined to areas near the proposed dam and along the lake shoreline, and (2) migration of salt water downstream from the dam generally would be limited to less than 1 mile and apparently would not reach equilibrium during the 100-year duration of the project. The modeling efforts did not include possible effects related to hydrodynamic dispersion in the brine- fresh-water system. Possible changes in the hydraulic conductivity of the aquifer, due to physical and chemical interactions in the brine and fresh-water environments, also were not considered.

Texas↗
USGS2000

Computer-model analysis of ground-water flow and simulated effects of contaminant remediation at Naval Weapons Industrial Reserve Plant, Dallas, Texas

In June 1993, the Department of the Navy, Southern Division Naval Facilities Engineering Command (SOUTHDIV), began a Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) of the Naval Weapons Industrial Reserve Plant (NWIRP) in north-central Texas. The RFI has found trichloroethene, dichloroethene, vinyl chloride, as well as chromium, lead, and other metallic residuum in the shallow alluvial aquifer underlying NWIRP. These findings and the possibility of on-site or off-site migration of contaminants prompted the need for a ground-water-flow model of the NWIRP area. The resulting U.S. Geological Survey (USGS) model: (1) defines aquifer properties, (2) computes water budgets, (3) delineates major flowpaths, and (4) simulates hydrologic effects of remediation activity. In addition to assisting with particle-tracking analyses, the calibrated model could support solute-transport modeling as well as help evaluate the effects of potential corrective action. The USGS model simulates steadystate and transient conditions of ground-water flow within a single model layer. The alluvial aquifer is within fluvial terrace deposits of Pleistocene age, which unconformably overlie the relatively impermeable Eagle Ford Shale of Late Cretaceous age. Over small distances and short periods, finer grained parts of the aquifer are separated hydraulically; however, most of the aquifer is connected circuitously through randomly distributed coarser grained sediments. The top of the underlying Eagle Ford Shale, a regional confining unit, is assumed to be the effective lower limit of ground-water circulation and chemical contamination. The calibrated steady-state model reproduces long-term average water levels within +5.1 or –3.5 feet of those observed; the standard error of the estimate is 1.07 feet with a mean residual of 0.02 foot. Hydraulic conductivity values range from 0.75 to 7.5 feet per day, and average about 4 feet per day. Specific yield values range from 0.005 to 0.15 and average about 0.08. Simulated infiltration rates range from 0 to 2.5 inches per year, depending mostly on local patterns of ground cover. Computer simulation indicates that, as of December 31, 1998, remediation systems at NWIRP were removing 7,375 cubic feet of water per day from the alluvial aquifer, with 3,050 cubic feet per day coming from aquifer storage. The resulting drawdown prevented 1,800 cubic feet per day of ground water from discharging into Cottonwood Bay, as well as inducing another 1,325 cubic feet per day into the aquifer from the bay. An additional 1,200 cubic feet of water per day (compared to pre-remediation conditions) was prevented from discharging into the west lagoon, east lagoon, Mountain Creek Lake, and Mountain Creek swale. Particle-tracking simulations, assuming an aquifer porosity of 0.15, were made to delineate flowpath patterns, or contaminant “capture zones,” resulting from 2.5- and 5-year periods of remediation activity at NWIRP. The resulting flowlines indicate three such zones, or areas from which ground water is simulated to have been removed during July 1996–December 1998, as well as extended areas from which ground water would be removed during the next 2.5 years (January 1999– June 2001). Simulation indicates that, as of December 31, 1998, the recovery trench was intercepting about 827 cubic feet per day of ground water that—without the trench—would have discharged into Cottonwood Bay. During this time, the trench is simulated to have removed about 3,221 cubic feet per day of water from the aquifer, with about 934 cubic feet per day (29 percent) coming from the south (Cottonwood Bay) side of the trench.

Texas↗
USGS2002

Adaptive moving mesh methods for simulating one-dimensional groundwater problems with sharp moving fronts

Accurate modelling of groundwater flow and transport with sharp moving fronts often involves high computational cost, when a fixed/uniform mesh is used. In this paper, we investigate the modelling of groundwater problems using a particular adaptive mesh method called the moving mesh partial differential equation approach. With this approach, the mesh is dynamically relocated through a partial differential equation to capture the evolving sharp fronts with a relatively small number of grid points. The mesh movement and physical system modelling are realized by solving the mesh movement and physical partial differential equations alternately. The method is applied to the modelling of a range of groundwater problems, including advection dominated chemical transport and reaction, non-linear infiltration in soil, and the coupling of density dependent flow and transport. Numerical results demonstrate that sharp moving fronts can be accurately and efficiently captured by the moving mesh approach. Also addressed are important implementation strategies, e.g. the construction of the monitor function based on the interpolation error, control of mesh concentration, and two-layer mesh movement. Copyright ?? 2002 John Wiley and Sons, Ltd.

International Journal for Numerical Methods in Eng↗
USGS2008

NetpathXL - An excel interface to the program NETPATH

NetpathXL is a revised version of NETPATH that runs under Windows? operating systems. NETPATH is a computer program that uses inverse geochemical modeling techniques to calculate net geochemical reactions that can account for changes in water composition between initial and final evolutionary waters in hydrologic systems. The inverse models also can account for the isotopic composition of waters and can be used to estimate radiocarbon ages of dissolved carbon in ground water. NETPATH relies on an auxiliary, database program, DB, to enter the chemical analyses and to perform speciation calculations that define total concentrations of elements, charge balance, and redox state of aqueous solutions that are then used in inverse modeling. Instead of DB, NetpathXL relies on Microsoft Excel? to enter the chemical analyses. The speciation calculation formerly included in DB is implemented within the program NetpathXL. A program DBXL can be used to translate files from the old DB format (.lon files) to NetpathXL spreadsheets, or to create new NetpathXL spreadsheets. Once users have a NetpathXL spreadsheet with the proper format, new spreadsheets can be generated by copying or saving NetpathXL spreadsheets. In addition, DBXL can convert NetpathXL spreadsheets to PHREEQC input files. New capabilities in PHREEQC (version 2.15) allow solution compositions to be written to a .lon file, and inverse models developed in PHREEQC to be written as NetpathXL .pat and model files. NetpathXL can open NetpathXL spreadsheets, NETPATH-format path files (.pat files), and NetpathXL-format path files (.pat files). Once the speciation calculations have been performed on a spreadsheet file or a .pat file has been opened, the NetpathXL calculation engine is identical to the original NETPATH. Development of models and viewing results in NetpathXL rely on keyboard entry as in NETPATH.

Techniques and Methods↗
USGS2002

Visualization of Flow Alternatives, Lower Missouri River

Background The U.S. Army Corps of Engineers (COE) 'Missouri River Master Water Control Manual' (Master Manual) review has resulted in consideration of many flow alternatives for managing the water in the river (COE, 2001; 1998a). The purpose of this report is to present flow-management alternative model results in a way that can be easily visualized and understood. This report was updated in October 2001 to focus on the specific flow-management alternatives presented by the COE in the 'Master Manual Revised Draft Environmental Impact Statement' (RDEIS; COE, 2001). The original version (February 2000) is available by clicking here. The COE, U.S. Fish and Wildlife Service (FWS), Missouri River states, and Missouri River basin tribes have been participating in discussions concerning water management of the Missouri River mainstem reservoir system (MRMRS), the Missouri River Bank Stabilization and Navigation Project, and the Kansas River reservoir system since 1986. These discussions include general input to the revision of the Master Manual as well as formal consultation under Section 7 of the Endangered Species Act. In 2000, the FWS issued a Biological Opinion that prescribed changes to reservoir management on the Missouri River that were believed to be necessary to preclude jeopardy to three endangered species, the pallid sturgeon, piping plover, and interior least tern (USFWS, 2000). The combined Missouri River system is large and complex, including many reservoirs, control structures, and free-flowing reaches extending over a broad region. The ability to assess future impacts of altered management scenarios necessarily involves complex, computational models that attempt to integrate physical, chemical, biological, and economic effects. Graphical visualization of the model output is intended to improve understanding of the differences among flow-management alternatives.

Colorado, Iowa, Kansas, Missouri, Montana, Nebrask↗
USGS1973

Water resources data for Missouri, water year 1973

Water resources data for the 1973 water year for Missouri including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water, are given in this report. In Part 1, records are included for 146 gaging stations of which 139 are streamflow discharge stations, and 7 are reservoir or lake stations; also are included records for 106 crest-stage partial-record stations. Locations of gaging stations are shown in figure 1. In Part 2, data on the quality of surface water (chemical, temperature, and sediment) were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 30-, or 60minute intervals. Records are given for 114 sampling stations of which 25 are partial-record stations, and 30 are miscellaneous sites. Locations of water-quality stations are shown in figure 2. A few pertinent stations (not included above) in bordering states are also included in this report. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Anthony Homyk, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Missouri. Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports on a State-boundary basis. Water-quality records beginning with the 1964 water year have been similarly released either in separate reports or in conjunction with streamflow records. These reports are for limited distribution and are designed primarily for rapid release of data shortly after the end of the water year.

Missouri↗