Reports

A study in cooperation with the Papio-Missouri River Natural Resources District was completed in 2019 to determine the concentration of contaminants of emerging concern (CEC) in groundwater in the Papio-Missouri River Natural Resources District, eastern Nebraska. Each well was sampled twice (in June and October or November) in 2019, totaling 34 samples. Samples were analyzed for 132 CECs...

Manganese and 1,4-dioxane in groundwater underlying Long Island, New York, were modeled with machine learning methods to demonstrate the use of these methods for mapping contaminants in groundwater in the Long Island aquifer system. XGBoost, a gradient boosted, ensemble tree method, was applied to data from 910 wells for manganese and 553 wells for 1,4-dioxane. Explanatory variables...

The U.S. Geological Survey (USGS) Fundamental Science Practices (FSP) are a set of standard principles fundamental to how USGS conducts and carries out its science activities and how resulting information products and data are reviewed, approved, and released. These policies, practices, philosophical premises, and operational principles serve as the foundation for all USGS research and...

Groundwater samples were collected during 2019 and 2020 from 23 wells in the Great Miami buried-valley aquifer (GM-BVA) in southwestern Ohio by the U.S. Geological Survey, in cooperation with the Miami Conservancy District, Dayton, Ohio, to determine concentrations of selected per- and polyfluoroalkyl substances (PFAS). The GM-BVA is a glacial outwash and alluvial fill aquifer that is...

Wildfire affects many types of communities and is a particular concern for communities in the wildland urban interface (WUI), such as those of Park County, Colorado. The core intent of this project was to provide evidence to support the Platte Canyon Fire Protection District (PCFPD) and Fire Adapted Bailey in their wildfire mitigation and education programming. This report describes...

Introduction The Chesapeake Bay Program (CBP) has operated a geographic information system (GIS) program since the early 1990s to address the established and growing need for and use of geospatial data, maps, and analysis within the CBP Partnership. This report is intended to detail the standard operating procedures of the CBP GIS program and address the quality assurance, quality...

The Southern California Earthquake Center (SCEC) workshop “Dynamic Rupture TAG – Investigating New Ideas in Earthquake Source Mechanics” was convened on Zoom on January 12, 2023. A total of 60 people participated. Our workshop attendees included scientists from 28 institutions and 11 countries (United States of America, Australia, Brazil, Czech Republic, China, France, Germany, Japan...

Small and/or artificially reduced populations can suffer genetic erosion with long-term consequences to population fitness and persistence. However, managers must periodically remove free-roaming horses from the landscape to reduce the risk of habitat degradation. We developed an individual-based population simulation model to evaluate the expected change in genetic diversity after 100...

Des Moines Water Works (DMWW) is one of the largest water providers in Iowa and as population growth continues, demand for drinking water is increasing. DMWW uses groundwater and surface water as raw water sources to supply the City of Des Moines and surrounding communities. In response to current and future demands, DMWW is in need of a thorough understanding of local groundwater...

The use of field deployable fluorescence sensors by the U.S. Geological Survey has become increasingly common for a wide variety of surface water and groundwater investigations. This report addresses field deployable fluorometers that measure the fluorescence response of various substances in water exposed to incident light generated by the sensor. An introduction to the basic principles...

For more than 25 years, the U.S. Geological Survey (USGS) has used the remote-sensing capabilities of United States National Imagery Systems (USNIS) to obtain high-resolution electro-optical imagery to monitor Earth’s response to global environmental change. A major focus has been monitoring sea ice behavior in the Arctic Ocean and its marginal seas. In 1997 and 1998, under the direction...

The purpose of this report is to describe the assembly methods for an external acoustic transmitter attachment device that can be used during fish telemetry studies. External attachment is a simple procedure that can limit handling and reduce recovery times on fish. This report provides step-by-step directions to assemble devices; this assembly method can be used for telemetry studies...