The new Introduction to Environmental Engineering and Science covers the basics needed to understand technology, manage resources, control pollution, and successfully comply with the regulations. Thoroughly updated and expanded, this edition features a new chapter and new coverage on risk and uncertainty analyses; hydrology; basic principles of soil science, soil erosion, and sedimentation; mining; and policies, programs, and the latest status reports on key environmental issues.

Introduction to Environmental Engineering and Science

The concept of indexing water with a numerical value to express its quality, based on physical, chemical and biological measurements, was developed in 1965 by US based National Sanitation Foundation (NSF). In NSFWQI, the selection of parameters is based on Delphi method and these models were formulated in additive and multiplicative forms. The models were implemented across various states in the US while being continually refined. One refined form is known as Oregon Water Quality Index (OWQI). The index enjoys the advantage of being free from the arbitration in weighting the parameters and employs the concept of harmonic averaging. Another model of WQI from Europe (Spain) is that of Bascaron (Bol. Inf. Medio Ambient. 9:30–51, 1979), which is based on the normalization of the concentrations of the water quality parameters and then aggregating them through an additive model with suitable weights attached to the parameters involved. The major differences in various WQIs are based on the mannerism of statistical integration and interpretation of parameter values. A totally different approach was adopted in the Canadian Water Quality Index also known as Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI). CCME WQI and is also being used by many countries all over the world and has also been endorsed by United Nations Environmental Program (UNEP) in 2007 as a model for Global Drinking Water Quality Index (GDWQI). The most commonly used parameters are dissolved oxygen, pH, turbidity, total dissolved solids, nitrates, phosphates, metals among others. All indices have one or other limitation and the search for a perfect one is still a challenge.

https://link.springer.com/content/pdf/10.1007%2Fs12403-011-0040-0.pdf

A Review of Genesis and Evolution of Water Quality Index (WQI) and Some Future Directions

A review of water quality index models and their use for assessing surface water quality

Occurrence of bisphenol A in surface water, drinking water and plasma from Malaysia with exposure assessment from consumption of drinking water.

Recycled Fibers in Reinforced Concrete: a systematic literature review

Water quality degradation in the Selangor River will still be present in the years to come since pollutant loads from poultry farms, municipal wastewaters, and industrial wastewaters are not envisaged to be handled effectively. This will be facing the problems of water quality status to use for multiple purposes and to provide its aquatic environment continuously. The water quality evaluation system is used to assess the water quality condition in the river. This system distinguishes two categories of water condition i.e., the water quality index and water quality aptitude. The assessment of water quality for the Selangor River from nine stations along the main stream, which concludes that water has been highly polluted (index 5) immediately downstream of station 02 Selangor River before confluence with Kubu River due to high concentration of microorganisms and immediately downstream of station 06 Selangor River before confluence with Batang Kali River due to high concentrations of microorganisms and suspended particles, was verified. Mineral micropollutants were found to gradually pollute the stream water, ranging from the unpolluted water (index 1) in the upstream to the bad quality (index 4) in the downstream area.

Assessment of Water Quality Status for the Selangor River in Malaysia

Malaysia is composed of the Peninsular Malaysia and the states of Sabah and Sarawak in the island of Borneo. As a country that moving forward to achieve the industrialized country status by the year 2020, Malaysia cannot escape from facing the solid waste management problems. There are a total 230 landfill in Malaysia. Landfills have been the most common methods of organized waste disposal. In most cases, open dumping is being practiced and takes place at about 50% of the total landfills. In addition, many landfills have opted to close rather than meet new while the quantity of waste generated yearly is much faster than the natural degradation process. Last year, about 7.34 million tones of solid wastes were generated, enough to fill up 42 buildings the same size as that of the world-renowned Petronas Twin Tower. Which each person generates about 1kg of solid waste per day. This solid waste volume is still increasing at the rate of 1.5% per year due to increase in urbanizations, change in living standards and consumption patterns. The case study, Ampar Tenang Landfill is situated near Sungai Labu, Sepang. Due to the continuous domestic waste generation, Ampar Tenang Landfill also currently overloading and serious leacheate spilling over the adjacent areas to the nearby Sungai Labu which is the main water supply for the Sepang and Nilai locality. Majority of the landfills in Malaysia are crude dumping ground, thus cause natural resource polluted and various environmental problems such as health hazards, surface water and ground water contamination, odors, etc. There are other treatment and/or disposal methods such as incineration and composting which could moderate the solid waste problems but they are not economically and socially viable at this moment. Thus, waste reduction, recovery and recycling play important roles in tackling the pressing solid waste problems.

An overview of landfill management and technologies: a Malaysian case study at Ampar Tenang

Objectives: To determine the reinforcing effect of a cheap Recycle Polyethylene Terephthalate (PET) fibre on asphalt concrete strength. The aim of this study was achieved by performing Resilient Modulus (MR) test in the laboratory on both unreinforced (i.e. neat asphalt mixture) and recycle PET fibre reinforced asphalt concrete mixtures. Methods: The percentage additions of recycle PET fibres are 0.3%, 0.5%, 0.7% and 1% of the total weight of the mixture. The result was analyzed by means of Response Surface Methodology (RSM) using Design Expert 7.0 software and validated using analysis of variance (ANOVA). Findings: The results indicated that recycle PET fibres have significantly increased the mixtures’ resilient modulus in lower temperature hence improved fatigue resistance, and moderately increased mixtures, resilient modulus at higher temperature hence improved rutting resistance. Novelty/Improvement: This research has introduced a sustainable means of producing Recycle fibres for the reinforcement of asphalt concrete mixtures. Recycle PET fibre have proved to be effective in strength improvement at 0.7% of total weight of asphalt concrete mixture.

Reinforcement of Asphalt Concrete Mixture using Recycle Polyethylene Terephthalate Fibre

In recent years, more studies had been conducted about train dwell time as it is a key
parameter of rail system performance and reliability. This paper draws an overview of train
dwell time models for rail passenger service from various continents, namely Asia, North
America, Europe and Australia. The factors affecting train dwell time are identified and
analysed across some rail network operators. The dwell time models developed by various
researches are also discussed and reviewed. Finally, the contributions from the outcomes of
these models are briefly addressed. In conclusion, this paper suggests that there is a need to
further study the factors with strong influence upon dwell time to improve the quality of the
train services.

/pdf/train-dwell-time-models-for-rail-passenger-service-3m2zk6xdxd.pdf

Mohd Idrus Mohd Masirin

Papers

Assessment of Water Quality Status for the Selangor River in Malaysia

An overview of landfill management and technologies: a Malaysian case study at Ampar Tenang

Reinforcement of Asphalt Concrete Mixture using Recycle Polyethylene Terephthalate Fibre

Train dwell time models for rail passenger service

Safety and Health Factors Influencing Performance of Malaysian Low-Cost Housing: Structural Equation Modeling (SEM) Approach