scholarly journals Relations that affect the probability and prediction of nitrate concentration in private wells in the glacial aquifer system in the United States

2010 ◽  
Author(s):  
Kelly L. Warner ◽  
Terri L. Arnold
Keyword(s):  
United States ◽  
Nitrate Concentration ◽  
The United States ◽  
Aquifer System ◽  
Private Wells

scholarly journals Giardiasis in the United States – an epidemiologic and geospatial analysis of county-level drinking water and sanitation data, 1993–2010

2015 ◽  
Vol 14 (2) ◽  
pp. 267-279 ◽  
Author(s):  
Kerry Schnell ◽  
Sarah Collier ◽  
Gordana Derado ◽  
Jonathan Yoder ◽  
Julia Warner Gargano
Keyword(s):  
United States ◽  
Negative Binomial ◽  
Parasitic Infection ◽  
The United States ◽  
Incidence Rates ◽  
County Level ◽  
Septic System ◽  
Water And Sanitation ◽  
South Central ◽  
Private Wells

Giardiasis is the most commonly reported intestinal parasitic infection in the United States. Outbreak investigations have implicated poorly maintained private wells, and hypothesized a role for wastewater systems in giardiasis transmission. Surveillance data consistently show geographic variability in reported giardiasis incidence. We explored county-level associations between giardiasis cases, household water and sanitation (1990 census), and US Census division. Using 368,847 reported giardiasis cases (1993–2010), we mapped county-level giardiasis incidence rates, private well reliance, and septic system reliance, and assessed spatiotemporal clustering of giardiasis. We used negative binomial regression to evaluate county-level associations between giardiasis rates, region, and well and septic reliance, adjusted for demographics. Adjusted giardiasis incidence rate ratios (aIRRs) were highest (aIRR 1.3; 95% confidence interval 1.2–1.5) in counties with higher private well reliance. There was no significant association between giardiasis and septic system reliance in adjusted models. Consistent with visual geographic distributions, the aIRR of giardiasis was highest in New England (aIRR 3.3; 95% CI 2.9–3.9; reference West South Central region). Our results suggest that, in the USA, private wells are relevant to giardiasis transmission; giardiasis risk factors might vary regionally; and up-to-date, location-specific national data on water sources and sanitation methods are needed.

scholarly journals State-level policies concerning private wells in the United States

Water Policy ◽  
2019 ◽  
Vol 21 (2) ◽  
pp. 428-435 ◽  
Author(s):  
Kristina Bowen ◽  
Tara Krishna ◽  
Lorraine Backer ◽  
Kate Hodgins ◽  
Lance A. Waller ◽  
...  
Keyword(s):  
United States ◽  
Water Policy ◽  
State Level ◽  
The United States ◽  
Construction Safety ◽  
State Agencies ◽  
Well Drilling ◽  
Federal Policies ◽  
Geographic Differences ◽  
Private Wells

Abstract Currently, no federal policies exist in the United States regarding private wells; this authority is devolved to states. This study inventoried state-level policies governing private wells in the United States in order to identify the topics addressed by each state, division of responsibilities across state agencies, and geographic differences in policy comprehensiveness. From May to August 2018, two independent reviewers conducted an online search followed by directly contacting state agencies (98% response) to identify all state-level policies in the United States that directly reference private wells. The search, updated in April 2018, confirmed the existing water policy list and identified 23 additional policies. Policies were then coded according to nine not-mutually-exclusive classifications. The results indicate that all states had at least one policy addressing private well drilling or construction. Significant geographic differences exist in maintenance related policies. In conclusion, although drilling and construction safety are addressed by each state, some policy domains are addressed inconsistently across states, and other policy domains are absent in most states.

Silver Sorption by Manganese Oxide

1996 ◽  
Vol 432 ◽  
Author(s):  
R. Ravikumar ◽  
D. W. Fuerstenau
Keyword(s):  
United States ◽  
Manganese Oxide ◽  
Ph Value ◽  
Nitrate Concentration ◽  
Background Electrolyte ◽  
Oxide Phase ◽  
The United States ◽  
Potassium Nitrate ◽  
Solution Chemistry ◽  
Sorption Data

AbstractSilver-manganese oxide ores are present in western United States, Mexico, South America, and Sumatra. The amount of silver varies between a few parts per million (ppm) to thousands of ppm. However, these ores are not compatible with conventional metallurgical treatment for the extraction of silver. This research is the study of the nature of silver binding with one model manganese oxide phase, cryptomelane. Cryptomelane is widely present in the United States and in parts of Colorado, with silver-bearing cryptomelane ore bodies containing up to a maximum of 1 wt% of silver. In order to better understand the nature of silver binding in cryptomelane, synthetic samples of cryptomelane were prepared and characterized, and then used for silver sorption experiments. The silver uptake appears to be a function of the solution chemistry conditions, pH and potassium nitrate concentration. The sorption of silver was found to increase with decreasing pH and at a fixed pH value, the sorption density was higher at a lower potassium nitrate concentration. Kinetics and equilibrium sorption data from lithium and sodium nitrate background electrolyte demonstrates three main results: firstly, most of the uptake of silver is compensated by release of potassium; secondly, the exchange for silver with protons and potassium ions is almost stoichiometric; and lastly, the importance of tunnel sites for the sorption reaction in cryptomelane. An ion-exchange model for the uptake of silver onto cryptomelane will also be discussed.

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