Applied Mechanics and Materials Vol. 802

Abstract: In the present study, two parameters, the per capita flow and the design criterion, were investigated. The investigation was performed on a manhole located between the library and sports complex within Universiti Malaysia Pahang, Gambang campus (UMP Gambang) where field monitoring of sewage flows was conducted. ISCO 2150 area-velocity flowmeter was used to collect the flow data and Flowlink 5.1 software was used for data retrieval as well as display. Calibration of the flowmeter was done in the Hydraulics and Hydrology Laboratory of UMP Gambang. The study duration was from November 2014 to February 2015. Each set of data consists of sewage flow readings every 5 minutes for duration of two weeks. The same data measurement interval was applied to the rainfall data, collected through an ISCO 675 rain gauge. From the results obtained, both the parameters investigated were found to be lower than their respective values stated in the Malaysia Standard MS1228:1991. After analysis of the results, it can be concluded that the flow characteristics in the sewerage system studied is sufficient to cater to the population equivalent in the study.

Abstract: Riverbank filtration (RBF) is a natural water pre – treatment, safer and cost – effective that uses geology instead of chemicals to pre – treat river water. The process occur during the infiltration process of river water passing through riverbank material towards a production well during a pumping test, where the removal of biological and colloids take place. Abstraction of ground water are required for RBF to occur, hence pumping test were done. As pumping test took place, ground water was in continuous discharging and recharging process throughout time. Objective of this research is to study the dynamic changes of ground water during discharging and recharging process for 72 hours by using time – lapse electrical resistivity imaging (TLERI). Resistivity, which uses current to measure the resistivity of subsurface was used during the pumping test to monitor ground water changes and infiltration of river water during RBF process. Results show significant changes on TLERI data from the first session until the last session. Dynamic changes occurred around the riverbank and production well section while others show less significant changes.

Abstract: Water abstraction for water treatment of portable water especially riverbank filtration (RBF) is essential to be safe and clean. Due to the awareness towards the spread of contaminants and deterioration of water resources, the needs of artificial barrier is seen as crucial. An artificial barrier is a man-made vertical barrier to pre-treat the abstraction water from the water intake structure. The proposed artificial barrier is a mixture of sand (local soil), granular activated carbon (GAC) and zeolite. In this study, the three adsorbents were tested for their adsorption and permeability. The effects of adsorbent dose on the adsorption of the turbidity, iron and zinc were investigated. After treatment with sand, the levels of turbidity, iron and zinc were observed to decrease by 93.7%, 85.15% and 68.5%, respectively. For GAC, the levels of turbidity, iron and zinc decreased by 96.9%, 99.2% and 36.3%, respectively. The reduction on the levels of turbidity, iron and zinc was preferable by zeolite with 98.3%, 93.0% and 98.8%, respectively. By using Langmuir and Freundlich adsorption isotherm, the result indicated that the adsorption of adsorbents mostly obeyed Freundlich model. The relationship is an empirical equation which has an asymptotic maximum as pressure increase without bond.

Abstract: Experimental study of hydraulic physical model investigates the flow characteristics in the pump sump. The model features four pumps (7.91 L/s for pump 1 and 2, and 4.74 L/s for pump 3 and 4) with a total of 9 cases of study. Different values of water depth (180mm, 200mm, and 300mm) and pump flow rate (15L/s, 20L/s, and 25L/s) were conducted. Velocity measurements at the dividing cross section were obtained by an Acoustic Doppler Velocimeter (ADV), pump flow rate by flow meter (Dyna Handheld Transit Time Ultrasonic Flow Meters) and swirl angle in the suction intakes were measured by a vortimeter/rotometer. No vortices were occurred near the suction intake at the high and medium water level conditions. In the low water level condition with high flow rate (25L/s), vortex Type 4 or 5 were observed near the suction intake and this condition is unacceptable. Since this condition indicate the presence of vortices more than Types 2 and an uneven flow through the suction intake, this can be categorized as the worst case and not recommended for pump sump operation.

Abstract: The newly design free water surface (FWS) constructed wetland (CW) was based on the design recommended in the Urban Stormwater Management Manual for Malaysia (MSMA) 2^nd Edition, 2012. The design was apply and completed it construction in April 2014 in Engineering Campus, USM, with approximate area 5166m². Thus the aim of this study was to evaluate the initial performance of CW, which was evaluated based on the water quality index (WQI). The sampling was conducted from November 2014 until March 2015 and consist of fourteen (14) sampling points into three (3) different zones; forebay zone, macrophytes zones and micropool zone. The parameters measured include percentage saturation dissolved oxygen (DO %), pH, total suspended solid (TSS), biochemical oxygen demand (BOD), chemical oxygen demand (COD) and ammoniacal nitrogen (AN). Based on the result obtained, the highest WQI value was obtained at micropool zone with the range of 78.98-85.45 (82.71±3.35) as the lowest WQI value was obtained at macrophytes zone with the range of 68.13-77.96 (73.25± 3.42). The main treatment process occur in the macrophytes zone is nutrient uptake by emergent plants species as for forebay and micropool zones, main treatment process occur settlement and sedimentation. The result also showed that the removal rate showed difference among each zone; forebay zone was 0.93%, macrophytes zone was 2.79% and micropool zone was 5.64%. Based on the WQI value obtained, forebay and micropool zones fall in Class II and macrophytes fall in Class II and III.

Abstract: A geophysical method was used in studying the subsurface profile for investigating the aquifer existence at Jenderam Hilir, Selangor, Malaysia. The 2-D electrical resistivity technique is to determine the presence of aquifer suitable for groundwater abstraction. Resistivity was measured through an ABEM SAS 4000 Terrameter and ABEM Terrameter LS. 2-D electrical-imaging resistivity data of subsurface profile for each survey line were calculated inverse modelling, validate by borehole data which showed the lithology: sandy clay to sandy silt sediments more than 3 m deep, composed of alternating layers of silty and sand. The aquifer potential are mostly in silty sand zones which resistivity value should be within 60-800 ohm-m. Based on interpretation, a potential water-bearing aquifer was located at a depth of 3 m and below which is good agreement with interpreted results. 2-D underwater resistivity survey lines were conducted across the ground and river. Resistivity image was interpreted as silty sand under the river bed, which the subsurface aquifer on land has a physical contact with surface water. Result has shown that ground and underwater resistivity technique can be used as alternative method in finding a good location for groundwater abstraction.

Abstract: For a developing country such as Malaysia, riverbank/bed filtration (RBF) technology is still new and only few efforts have been made to understand the RBF mechanism and processes. Soil characteristics play important roles in determining the water quality and the ability of water to be abstracted from the wells during RBF process. A research has been carried out to identify the characteristic of riverbank soil at different layers in the pumping well (PW) borehole at Kota Lama Kiri, Kuala Kangsar, Perak, Malaysia. Soil samples were collected during the development of PW for RBF application. The maximum depth of PW was 8.50 metre. The soil samples were transported to Geotechnical Engineering Laboratory, School of Civil Engineering, Universiti Sains Malaysia and the properties were determined by a series of laboratory test. Soil particle size distribution (PSD) and hydraulic conductivity were obtained from sieve analyses and constant head test with reference to BS 1377: Part 1-9;2:1990. Laboratory results show that the value of C_u (coefficient of uniformity) for the soil samples within the borehole of PW was found to be within the range of 2.00 to 10.00 while the value of C_c (coefficient of gradation) lies in the ranges of 0.06-1.19. The One Way Analyses of Variance test was performed using Minitab statistical packages and the results indicate that the p-value was 0.996, where there was no significance difference between the mean sizes of soil samples within the PW. The hydraulic conductivity, k for PW ranges between 0.10-0.91 cm/s. Soil samples from depth 6.00-7.00 metres has the highest hydraulic conductivity, which is 0.91 cm/s. The overall well production from the pumping test was found 112.10 m³/hr.

Abstract: The colloidal borescope can be used for measuring groundwater flow directions and velocity. It is an integrated high-resolution flux gate compass with a high-magnification colloid-imaging camera that can measure flow at selected depths within a well. In this study, the colloidal borescope was used to determine flow direction and measure velocity during a pumping test for the riverbank filtration study in Jenderam Hilir, Selangor. During each measurement, the instrument, which monitored the movement of the suspended particles, was inserted into a well at a particular depth (screen well). The relative flow direction was determined by plotting the trajectory and speed of colloidal particles across the screen with AquaLITE Software, which determined the horizontal speed of the particles and flow speed. The groundwater flow pattern was dtermined at four boreholes in the study area, and the groundwater flow velocities were found ranging from 0.72 to 2.45 x (10^-4) m/s. The direction of the groundwater flow at boreholes monitoring well 02 (MW02) and monitoring well 19 (MW19) was moved toward borehole pumping well (PW). The groundwater flow at monitoring well 01 (MW01) was moving toward the northwest of the study site which was parallel with the Langat river. The groundwater flow in borehole monitoring well A (MWA) was toward the southern part of the study site and was not affected by the pumping test activities at borehole monitoring well 03 (MW03).

Abstract: Water tariff increase has been suggested as part of the water services industry reform agenda in Malaysia. This study explores the issue on Malaysian households’ willingness to pay (WTP) for a promised improved domestic water quality and services. Descriptive analysis on data from 262 household’s paid water users, the study found that majority of Malaysian household’s WTP to be at the less than RM5; these consist of those who live in rural and suburban areas (not urban), those within all income categories (except for those earning between RM6001-RM9000), and those with education level less than Master and above degree. The findings indicate the importance of socio-economic factor to be considered by SPAN and water services providers in any plans to increase water tariff.

Abstract: Great quantities of dredged marine soils (DMS) have been produced from the maintenance of channels depth, anchorages and for harbour development. Most of the DMS are disposed in the sea and land. DMS have the potential to pose ecological and human health risks and it is also considered as a geowaste. Malaysia is moving towards the sustainability approach and one of the key factors to achieve it is to reduce waste. Backfilling is the basic phase for every construction therefore it shows the importance of creating artificial land in this study. Thus, this geowaste should be generated as a new resource to substitute soil for civil works such as for artificial land creation. Moreover, there is no proper guideline for beneficial reuse of DMS in Malaysia. This paper proposes a preliminary framework for beneficial reuse of DMS in artificial land creation. The reuse of DMS requires an understanding of the managing procedure from retrieval of DMS to on-site application. The key components involved are transportation, storage and treatment of the material. Most existing guidelines only highlights on the treatment process of contaminants which affects human health and environment. Nevertheless, having a well-managed transportation system to transfer the DMS and pre-treating it if necessary to work as a soil for civil works are important as well. It is therefore necessary to develop a DMS Management Framework that enables a systematic guideline of reusing DMS for artificial land creation in Malaysia.