Assessment of Nitrate Contamination of Groundwater Using Lumped-parameter Models

Environmental Modelling & Software, Volume 24, Issue 9, September 2009, Pages 1073-1087

Lubna Hajhamad and Mohammad N. Almasri

“In this paper, lumped-parameter models (LPMs) were developed and utilized to simulate nitrate concentration in the groundwater of Gaza City and Jabalia Camp (GCJC) in the Gaza Coastal Aquifer (GCA) in Palestine. In the GCJC area, nitrate levels exceed the maximum contaminant level (MCL) of 10 mg/L NO3-N (45 mg/L NO3) in many wells. Elevated nitrate concentrations in the groundwater of GCJC area are due to the disposal of untreated wastewater, the existence of heavy agriculture in the surrounding areas, and the use of cesspits for wastewater disposal. The developed LPMs utilize monthly time steps and take into consideration all the sources and sinks of water and nitrate in the study area. The main outcomes of the LPMs are the average temporal water table elevation and nitrate concentration. In order to demonstrate LPMs usability, a set of management options to reduce nitrate concentration in the groundwater of the study area were proposed and evaluated using the developed LPMs. Four broad management options were considered where these options tackle the reduction of nitrate concentration in the lateral inflow, rehabilitation of the wastewater collection system, reduction in cesspit usage, and the restriction on the use of nitrogen-based fertilizers. In addition, management options that encompass different combinations of the single management options were taken into account. Different scenarios that correspond to the different management options were investigated. It was found based on the LPMs that individual management options were not effective in meeting the MCL of nitrate. However, the combination of the four single management options with full rehabilitation and coverage of the wastewater collection network along with at least 60% reduction in both nitrate concentration in the lateral inflow and the use of nitrogen-based fertilizers would meet the MCL constraint by the end of the management period.”

Introduction of Threat Analysis into the Land-use Planning Process

Journal of Hazardous Materials, Volume 163, Issues 2-3, 30 April 2009, Pages 683-700

Davor Kontić and Branko Kontić

“The subject of this paper is a method for introducing risk assessment into the land-use planning (LUP) process. Due to adaptations of the results of risk assessment, which are needed to make the risk assessment usable by land-use planners, we term the overall process threat analysis. The key features of the threat analysis can be summarised as follows. (i) It consists of three main steps. The first is determination of the threat intensity level of an accident, the second is analysis of the environmental vulnerability of the surroundings of an accident, and the third, integrating the previous two, is determination of a threat index in the accident impact zone. All three are presented in GIS based maps, since this is a common expression in LUP. (ii) It can and should be applied in the early stages of the LUP process. The methodology is illustrated by an example in the context of renewal of a land-use plan for the Municipality of Koper in Slovenia. The approach of threat analysis follows directions of the Article 12 of the Directive 96/82/EC of the European Commission (the Seveso II Directive).”

2010 Thacher Environmental Research Contest Entries Due by April 5, 2010

“The Institute for Global Environmental Strategies (IGES) announces the 2010 Thacher Environmental Research Contest. This national competition for secondary school students was founded in honor of former IGES board member Peter Thacher, who died in 1999. Peter Thacher was former deputy executive director of the United Nations Environment Program, NASA advisor, and, at the time of his death, president of the Earth Council Foundation/U.S. He was a leader in promoting the use of satellite remote sensing. Read about the 2009 winners.

“The 2010 Thacher awards will be given to secondary school students (grades 9-12) demonstrating the best use of satellites and other geospatial technologies or data to study Earth. Eligible tools and data include satellite remote sensing, aerial photography, geographic information systems (GIS), and Global Positioning System (GPS). The main focus of the project must be on the application of the geospatial tool(s) or data to study a problem related to Earth’s environment.

“Geospatial technologies and data have numerous uses in science research, ranging from climate prediction to archaeology. They can be used to improve our understanding of the Earth system, including interactions among the atmosphere, biosphere, geosphere and hydrosphere. They can also be used to improve the quality of our lives by supporting weather prediction, natural hazards monitoring, agriculture, land-use planning, coastal management, transportation, public health and emergency response.”