Filters: Types: OGC WFS Layer (X) > partyWithName: Craig Brown (X)
2 results (8ms)|
Filters
Date Range
Extensions Types Contacts
Categories Tag Types
|
A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH and when coupled with long flow paths, results in the most alkaline conditions. Conversely, in areas where glacial sediments are thin and carbonate-poor, pH conditions remain acidic. At depths typical of drinking-water supplies, predicted pH > 7.5 – which is associated with arsenic mobilization – occurs more frequently...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted regression trees,
Calcite saturation index,
Connecticut,
Geochemistry,
Geochemistry,
PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites (springs and expressions) in areas adjacent to the Catskill Aqueduct. In the area near the Delaware Aqueduct, which has been determined by the USGS to have a water-tunnel contribution to flooding issues during periods of high precipitation, the NYCDEP plans to repair the leaks with a grouting procedure. However, without monitoring...
|
|
