Environmental audit for registration of desalination plant at Mirihi Island Resort, South Ari Atoll

Abstract

The purpose of this Environmental Audit report is to fulfill the requirements of Maldives Water and Sanitation Authority guidelines to get necessary environmental clearance from the Environmental Protection Agency to carry out the registration of the desalination plant. The project involves environmental auditing of the existing desalination plant in Mirihi Island Resort for registration of the desalination plant. Desalination system involves one desalination plant with a total capacity of 100 tonnes per day and two water storage tanks with a capacity of 180 tonnes and 88 tonnes approximately. The seawater intake is located on the southeastern side of the island with a length of 12 m from the shoreline. The brine discharge point is located at the western side of the island at a distance of 5.8 m from the shoreline. The structural integrity of the facilities is considered good. Noise levels are perceived as high for a mixed residential and industrial zone although it must be taken into account that space is limited and location of staff areas near plant house is inevitable. The environmental impacts associated with this project include, increased noise levels and impact on marine environment due to brine discharge. There are indirect impacts associated with consumption of energy for desalination. Power generation has the potential to degrade air quality and contributes to global warming. In addition, fuel handling related to power generation is a potential risk for ground water and soil contamination from fuel spills and leaks. Noise measurements taken during the field visit conforms to international standards while marine water quality tests show normal conditions. However, live coral cover in the brine discharge area was found to relatively low compared to the ambient environment, which cannot be concluded as the cause for low level of coral cover. Visual observation identifies no notable damage to existing vegetation around the desalination plant house and no indication of any fuel spills or leaks around the area. Groundwater quality tests conducted is interpreted as a false result as the available conditions and data does not correlate with resultant due to some sort of analysis error. Mitigation measures that are in place to reduce the environmental impacts associated with the operation of the facility include appropriate distance of brine and sweater pipes from shoreline and installation of sound attenuators to reduce the noise levels from the plant house. In order to protect the environment from potential fuel spills, proper pipelines are established and fuel storage is in bunded areas. A monitoring plan is proposed to observe any changes taking place due to the operation of desalination plant. In the event that monitoring indicates that any environmental quality is deteriorating to unacceptable levels, the proponent will correct operation procedures that are contributing to the problem and/or undertake necessary engineering installations.