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Brian J. Mailloux Nicholas A. Procopio Mark Bakker Therese Chen Imtiaz Choudhury Kazi Matin Ahmed M. Rajib H. Mozumder Tyler Ellis Steve Chillrud Alexander van Geen 《Ground water》2021,59(1):80-89
Geogenic arsenic in drinking water is a worldwide problem. For private well owners, testing (e.g., private or government laboratory) is the main method to determine arsenic concentration. However, the temporal variability of arsenic concentrations is not well characterized and it is not clear how often private wells should be tested. To answer this question, three datasets, two new and one publicly available, with temporal arsenic data were utilized: 6370 private wells from New Jersey tested at least twice since 2002, 2174 wells from the USGS NAWQA database, and 391 private wells sampled 14 years apart from Bangladesh. Two arsenic drinking water standards are used for the analysis: 10 µg/L, the WHO guideline and EPA standard or maximum contaminant level (MCL) and 5 µg/L, the New Jersey MCL. A rate of change was determined for each well and these rates were used to predict the temporal change in arsenic for a range of initial arsenic concentrations below an MCL. For each MCL and initial concentration, the probability of exceeding an MCL over time was predicted. Results show that to limit a person to below a 5% chance of drinking water above an MCL, wells that are ½ an MCL and above should be tested every year and wells below ½ an MCL should be tested every 5 years. These results indicate that one test result below an MCL is inadequate to ensure long-term compliance. Future recommendations should account for temporal variability when creating drinking water standards and guidance for private well owners. 相似文献
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Adaptation behavior in the face of global climate change: Survey responses from experts and decision makers serving the Florida Keys 总被引：2，自引：0，他引：2
We conduct a survey to elicit responses from experts and decision makers serving the Florida Keys regarding vulnerability to global climate change. Study findings reveal deep concern among federal, state and local experts and decision makers about adverse impacts at the local level. A large majority of respondents recognize the increasing likelihood of dynamic, potentially irreversible, socioeconomic and ecological repercussions for the Florida Keys. However, very few experts and decision makers report that their respective agencies have developed formal adaptation plans. Respondents identify significant institutional and social barriers to adaptation and convey their support for a host of strategic measures to facilitate adaptation on an urgent basis. The implications of our findings are discussed in the context of enhancing adaptive capacity and resilience in the Florida Keys and beyond. Information generated from this study can provide functional guidance for improving decision-support systems and promoting adaptation policies. 相似文献
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Chitrini Mozumder K. Venkata Reddy Deva Pratap 《Journal of the Indian Society of Remote Sensing》2013,41(2):269-277
There is a need for timely information about changes in the air pollution levels in cities for adopting precautionary measures. Keeping this in view, an attempt has been made to develop a model which will be useful to obtain air quality information directly from remotely sensed data easily and quickly. For this study pixel values, vegetation indices and urbanization index from IRS P6 LISS IV and Landsat ETM+ images were used to develop regression based models with Air Pollution Index (API), which were calculated from in-situ air pollutant information. It was found that among the 12 parameters of IRS, highest correlation exists between pixel values in NIR (Near Infra-Red) band (Pearson correlation ?0.77) and Normalized Difference Vegetation Index (NDVI) (Pearson correlation ?0.68) and both have inverse relationship with API. In case of Landsat, the highest correlation was observed in SWIR (Short Wave Infra-Red) band (Pearson correlation ?0.83) and NIR (Pearson correlation ?0.78). Both single and multivariate regression models were calibrated from best correlated variables from IRS and Landsat. Among all the models, multivariate regression model from Landsat with four most correlated variables gave the most accurate air pollution image. On comparison between the API modeled and API interpolated images, 90.5 % accuracy was obtained. 相似文献
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Evidence for Elevated Levels of Arsenic in Public Wells of Bangladesh Due To Improper Installation 
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下载免费PDF全文 I. Choudhury K. M. Ahmed M. Hasan M. R. H. Mozumder P. S. K. Knappett T. Ellis A. van Geen 《Ground water》2016,54(6):871-877
One of the mainstays of mitigation to reduce the exposure of the rural population of Bangladesh to arsenic (As) from private, mostly <90‐m deep wells over the past 15 years has been the installation of over 300,000 deeper community wells. A comprehensive testing campaign previously conducted across a 180 km2 of area of Bangladesh identified 9 out of total of 927 wells >90 m deep that contained >50 µg/L arsenic. We show here that for five of these nine wells, conductivity profiles obtained after spiking the well bore with salt indicate a shallow leak that could explain the high As in the well water. In two of the five leaky wells, the presence of additional screens at the depth of the leak was documented with a downhole camera. The downhole camera did not detect anomalies in the construction of the remaining three leaky wells or in the four wells that did not leak. The four wells that did not leak were all >150‐m deep and located in two villages separated by less than 500 m. Excluding these two villages and a handful of leaky wells, the results indicate an aquifer that is consistently low in As over a sizeable area at depths >90 m. Isolated cases of public wells that are elevated in As that have been reported elsewhere in Bangladesh may therefore reflect improper installation rather than actual contamination of the deep aquifer. 相似文献
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Thungyani N. Ovung Jyotisankar Ray Biswajit Ghosh Debabrata Mandal Pallab Dasgupta Madhuparna Paul 《Journal of the Geological Society of India》2017,90(2):154-158
Serpentinization is pervasive in the ultramafic rocks of Manipur ophiolite belt (MOB), Northeastern India. Electron microprobe data of a serpentinite from the Ukhrul-Nungbi sector of MOB shows Ni-rich serpentine mineral (NiO = 33.4-33.9 wt %, SiO2= 37.55-38.96 wt %, MgO= 14.83-16.89 wt %). The composition and X-ray diffraction pattern characterize this Ni-rich serpentine mineral as népouite which is suggested to be a hydrothermal alteration product of NiO-rich olivine in a fore-arc peridotite. The genesis of this NiO-rich olivine is attributed to the melt-rock interaction in a supra-subduction zone setting. 相似文献
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Facilitating adaptation to global climate change: perspectives from experts and decision makers serving the Florida Keys 总被引：2，自引：1，他引：1
Slivers of land amidst the world’s third largest barrier reef, the Florida Keys provide unique insights on the emerging challenges associated with adaptation to global climate change. While political will and public awareness are gradually shifting on the imposing risks, analysis of survey responses from experts and decision makers serving the Florida Keys (federal, state and local personnel) reveals insufficient resources, limited direction and leadership, and lack of institutional frameworks to facilitate the adaptation process. Against this backdrop, we investigate experts and decision makers’ interest in an array of adaptation measures including their willingness to support a proposed ‘Community Adaptation Fund’ (CAF) to mobilize resources and lay the foundation for adaptation initiatives in the Florida Keys. We also explore potential funding sources for establishing the proposed CAF, and test the feasibility of a diverse set of financing mechanisms. We discuss implications of our findings in the context of enhancing adaptive capacity in the Florida Keys and beyond. 相似文献
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