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Lane B. Simmons

Publications and source records attributed to Lane B. Simmons.

3 recordsLinked to original sources

The US XPD-24–200—An isokinetic suspended-sediment and water-quality collapsible-bag sampler with point- or depth-integrating sampling capabilities

Accurate collection of fluvial suspended‑sediment and water‑quality samples is essential for understanding transport processes, evaluating river health, quantifying loads, and supporting regulatory and management decisions. Since 1939, the Federal Interagency Sedimentation Project (FISP) has led the development and standardization of sediment‑sampling equipment and methods across Federal agencies. Although substantial advancements have been made, the most recent point‑integrating sampler developed in 2006 has notable limitations, including insufficient sample volume for low‑concentration analyses and a mechanically complex pressure‑equalization system required for a rigid-bottle sample container. To address these limitations, FISP collaborated with Carnet Technology to design, fabricate, and test a new collapsible‑bag sampler capable of collecting larger sample volumes and operating as either a point‑integrating or depth‑integrating sampler. The resulting sampler, the US XPD‑24‑200, was evaluated through controlled tow‑tank tests and field testing in a lake environment. Results indicate that the US XPD‑24‑200 can collect a 5.5-fold increase in maximum sample volume than a pre-existing point sampler developed in 2006. The US XPD‑24‑200 performs isokinetically within the expected intake efficiency (IE) range under most conditions. Approximately 73 percent of IEs fell within the target range of 0.9–1.1. A mild bias was observed with IE values outside this range that were predominantly lower than 0.9 and occurred most frequently at the lower test velocities, whereas only 2 percent of IEs exceeded 1.1, primarily at the highest velocities tested. Tow‑tank tests produced tightly clustered IE values with low variability, demonstrating stable performance under controlled conditions. Lake towing tests exhibited more variability, reflecting natural environmental influences such as turbulence, temperature gradients, and unsteady inflow. Collectively, the results demonstrate that the US XPD‑24‑200 provides reliable IEs comparable to existing samplers while offering increased sample volume, reduced mechanical complexity, and enhanced operational flexibility.

Open-File Report

Revisions to suspended-sediment concentration, percent smaller than 0.063 millimeter, and instantaneous suspended-sediment discharge reported for a cooperative program between the U.S. Geological Survey and the U.S. Army Corps of Engineers in the lower Mississippi-Atchafalaya River Basin, October 1989 to February 2015

This report presents revised results for four parameters reported for suspended-sediment samples that were collected in the lower Mississippi-Atchafalaya River Basin as part of a cooperative program between the U.S. Army Corps of Engineers, Mississippi Valley Division, New Orleans District and the U.S. Geological Survey (USGS). The cooperative program has been active since 1973 at seven sites: two sites on the main stem of the Mississippi River, three sites on the Atchafalaya River, one site on the Old River Outflow Channel, and one site on the lower Red River above the confluence with the Old River Outflow Channel. The four parameters—suspended-sediment concentration, percent by mass of the sediment that passes through a 0.063-millimeter (US 230) sieve, instantaneous stream discharge, and instantaneous suspended-sediment discharge—reported for 2,895 samples have been modified to reflect the findings of a full review of the cooperative program, which was initiated by both agencies in January 2015. The revised results are for samples collected from October 1989 through February 2015. Ninety-four percent of the revised values for suspended-sediment concentration are lower than their corresponding original reported values, indicating that less suspended sediment moves through the lower Mississippi River system than was previously reported. For example, the median revised instantaneous suspended-sediment discharge at the Mississippi River at Tarbert Landing, Miss. (USGS station 07295100), was 315,000 short tons per day, compared to 378,000 short tons per day as originally reported. At the Atchafalaya River at Simmesport, La. (USGS station 07381490), the median revised suspended-sediment discharge was 105,000 short tons per day, compared to 143,000 short tons per day as originally reported. The systematic downward revision in instantaneous suspended-sediment discharge values was due to a systematic downward revision in the suspended fine (less than 0.063 millimeter) sediment concentration. The effect of the revision on the suspended-sand concentration and instantaneous suspended-sand discharge was weaker. Any model of sediment load or transport processes in the basin that uses data from the affected samples should be reevaluated on the basis of the revised results.

Lower Mississippi basin

Quality of water in domestic wells in the Chicot and Chicot equivalent aquifer systems, southern Louisiana and southwestern Mississippi, 2000-2001

In 2000-2001, water-quality data were collected from 60 randomly selected domestic wells in the Acadian-Pontchartrain Study Unit, as part of the National Water-Quality Assessment Program. The data were collected from wells screened in shallow sands (less than 350 feet below land surface) in two major aquifer systems--the Chicot aquifer system in southwestern Louisiana and the Chicot equivalent aquifer system in southeastern Louisiana and southwestern Mississippi. The Chicot equivalent aquifer system is part of the Southern Hills regional aquifer system, and both the Chicot aquifer system and the Southern Hills regional aquifer systems are designated as sole-source aquifers by the U.S. Environmental Protection Agency (USEPA). The well depths ranged from 40 to 340 feet below land surface with a median depth of 120 feet. The ground-water-quality data included 5 physiochemical properties, dissolved solids, 9 major inorganic ions, 24 trace elements, 6 nutrients, dissolved organic carbon, 109 pesticides and degradation products, and 85 volatile organic compounds (VOC's); and a subset of the wells were sampled for radon, chlorofluorocarbons, and stable isotopes. Water from 35 of the 60 domestic wells sampled had pH values less than the USEPA Seconday Maximum Contaminant Level (SMCL) range of 6.5 to 8.5 standard units. Specific conductance ranged from 17 to 1,420 microsiemens per centimeter at 25 degrees Celsius. Dissolved-solids concentrations in water from two wells exceeded the SMCL of 500 mg/L (milligrams per liter); the maximum concentration was 858 mg/L. Sodium and calcium were the dominant cations, and bicarbonate and chloride were the dominant anions. One chloride concentration (264 mg/L) exceeded the SMCL of 250 mg/L. One arsenic concentration (55.3 micrograms per liter) exceeded the USEPA Maximum Contaminant Level (MCL) of 10 micrograms per liter. Iron concentrations in water from 22 wells exceeded the SMCL of 300 micrograms per liter; the maximum concentration was 8,670 micrograms per liter. Manganese concentrations in water from 26 wells exceeded the SMCL of 50 micrograms per liter; the maximum concentration was 481 micrograms per liter. Health Advisories have been established for six of the trace elements analyzed; no concentrations were greater than these nonenforceable standards. Radon concentrations in water from 9 of 50 wells sampled were greater thanthe proposed USEPA MCL of 300 picocuries per liter. Concentrations of ammonia, ammonia plus organic nitrogen, and nitrite plus nitrate in water from four wells were greater than 2 mg/L, a level that might indicate anthropogenic influences. The median dissolved organic carbon concentration was an estimated 0.30 mg/L, which indicated naturally occurring dissolved organic carbon conditions in the study area. Eight pesticides and two degradation products were detected in water from five wells. Twenty-four VOC's were detected in water from 44 wells. All concentrations of pesticides and VOC's were less than USEPA drinking-water standards. Quality-control samples, which included field-blank samples, replicates, and field and laboratory spikes, indicated no bias in ground-water data from collection procedures or analyses. VAriance between the environmental sampls and he corresponding replicate samples was typically less than 5 percent, indicating and acceptable degree of laboratory precision and data collection reproducibility. The Mann-Whitney rank-sum test was used to compare depth to top of screen and selected physicochemical properties and chemical constituents between six groups of wells. Values for selected physicochemical and chemical constituents were typically greater in wells located in the Chicot aquifer system than in the Chicot equivalent aquifer system. Values for specific conductance, pH, calcium, sodium, bicarbonate, chloride, dis

Water-Resources Investigations Report