A risk-based groundwater modeling framework in coastal aquifers: a case study on Long Island, New York, USA

A methodology is proposed to define indices for quantifying risks under the threat of reducing in groundwater levels, the existence of saltwater intrusion (SWI), and an increasing nitrate contamination load in submarine groundwater discharge (SGD). The proposed methodology considers coastal regions under geological heterogeneity and it is tested on a groundwater system in Nassau County of Long Island, New York (USA). The numerical model is constructed with the SEAWAT code. The parameter uncertainty of this model is evaluated by coupling the Latin hypercube sampling method (as a sampling algorithm) and Monte Carlo simulation to consider the uncertainty in both hydraulic conductivity and recharge rate. The indices are presented in spatial maps that classify areas of risk to potential threats. The results show that two of the water districts have a high risk under conditions of decreasing groundwater level. Salinity occurs in the southern and southwestern parts of the Nassau County aquifer and a considerable area of high risk of SWI is identified. Furthermore, the average SGD rate with the associated fluxes of nitrate is estimated as 81.4 million m3/year (average 0.8 tons of nitrate through SGD per year), which can adversely affect the quality of life in the local coastal ecosystems. The framework developed in this study could help the water district managers to identify high-risk areas for short-term and long-term planning and is applicable to other coastal settings.

Holocaust Denial Literature Twenty Years Later: A Follow-up Investigation of Public Librarians' Attitudes Regarding Acquisition and Access

This study was undertaken to learn about public librarians' attitudes and opinions concerning the sometimes conflicting issues of intellectual freedom, collection balance, and controversial materials, and whether those attitudes and opinions have changed over twenty years. The investigation focused on Holocaust denial literature, a body of work which ranges from minimizing the Holocaust to outright denying that it happened. Public librarians in Nassau County, New York, were surveyed, and the results were compared with a similar survey from 1992. The results indicate that librarians are even more open to Holocaust denial literature than they were twenty years ago and, regardless of outside pressures, would acquire and provide ready access to this material in their libraries.