Existing Environment
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Detailed Environmental Impact Assessment for the Proposed Reclamation for the Development Chapter 3 of Oil and Gas Industrial Base at Kg. Rancha-Rancha, Labuan, F.T., Malaysia Existing Environment Chapter 3 Existing Environment 3.1 Introduction This chapter outlines and records the existing conditions, in qualitative and quantitative terms, of the physico-chemical, biological and socio-economics environment at the project site (reclamation and sand borrow) and its surrounding areas (within 5-km radius) prior to implementation of the Project. As mentioned in Chapter 2, this Project two (2) sites, i.e. 1) the reclamation site, where proposed reclamation and capital dredging in near vicinity to attain the required draft; and 2) the proposed sand borrow site, where sand materials will be extracted and transported to the reclamation site. The purpose of describing the existing environmental setting is to establish a reliable “baseline”, which is an important pre-requisite for undertaking an environmental impact assessment and future project monitoring. 3.2 Physico-Chemical Environment 3.2.1 Bathymetry The bathymetrical database for this DEIA study is derived from the C-Map electronic chart. All depths are referred to chart datum and reference in Universal Transverse Mercator (UTM-50) coordinate system. Reclamation site: This site is located on the western side of Rancha-Rancha Industrial area facing the Sg Kina Benuwa bay. The bay morphology is composed by a mixture of sand mud and low lying rocks. The bathymetric at this site ranges from -1 MSL to -7 MSL. Sand borrow site: The bathymetric at this site ranges between -5 MSL and -12 MSL (from north to south). The bathymetry information regarding both sites can be referred to in Figure 3.2.1. Chemsain Konsultant Sdn. Bhd. Page C3-1 CK/EV403-4176/12 Detailed Environmental Impact Assessment for the Proposed Reclamation for the Development Chapter 3 of Oil and Gas Industrial Base at Kg. Rancha-Rancha, Labuan, F.T., Malaysia Existing Environment Figure 3.2.1: Bathymetries of the Reclamation and Sand Borrow Sites. 3.2.2 Tidal The tidal information at Labuan is readily available from year 1995 to 2003. Table 3.2.1 summarises the tidal details. Table 3.2.1: Tidal Range of Labuan Location Labuan Authority RMN MDS 7 year 1 year Length of Tidal Recording (1995-03) (2004-05) Highest Astronomical Tide (HAT) + 2.60m + 2.8m Mean Higher High Water (MHHW) + 2.33m + 2.5m Mean Lower High Water (MLHW) + 1.77m + 1.9m Mean Sea Level (MSL) + 1.34m + 1.4m Mean Higher Low Water (MHLW) + 0.91m + 1.0m Mean Lower Low Water (MLLW) + 0.34m + 0.4m Lowest Astronomical Tide (LAT) 0.00m 0.0m MHHW – MLLW 0.99m 2.1m *Notes: 1. All values in Chart Datum (CD). 2. RMN – National Hydrographic Centre, Royal Malaysian Navy. 3. MDS – Jabatan Laut Sarawak (Marine Department Sarawak). The tide within Labuan is considered mixed, dominantly diurnal tide with only one high water and one low water a day especially during spring tide. The semi-diurnal component becomes more apparent during neap tide. Tidal range (MHHW – MLLW) at the site is small with around 1.5 m to 2 m expected in most days except during spring tides. Chemsain Konsultant Sdn. Bhd. Page C3-2 CK/EV403-4176/12 Detailed Environmental Impact Assessment for the Proposed Reclamation for the Development Chapter 3 of Oil and Gas Industrial Base at Kg. Rancha-Rancha, Labuan, F.T., Malaysia Existing Environment 3.2.3 Current On regional scale, current patterns are dominated by the two monsoon seasons. During the North East Monsoon, the oceanic current of the South China Sea’s main circulation commences from current entering from Pacific Ocean through the gap between Taiwan and the Philippines known as Kuroshio Intrusion. As it enters South China Sea it travels along the southern coast of China and Vietnam and heads towards Karimata Strait. Off the coast of northern Sarawak and Sabah outside the continental shelf it branches off and turns northeast in direction as shown in the simplified current flow pattern of South China Sea during the north east monsoon in Figure 3.2.2. Figure 3.2.2: Kuroshio Intrusion in the northern South China Sea and subsequent through branching offshore Vietnam, turning north-east and following the north- west coast of Borneo up to Sabah. During the South West Monsoon the main current flow reverse the flow from Karimata Strait towards the Vietnam and southern China and into Pacific Ocean. Off the coast of northern Sarawak and Sabah, the current, similar to that occurred during the North East monsoon, flows north east. It can thus be concluded that the oceanic current off shore of both the reclamation and sand borrow sites are predominantly towards the north east. However, as both sites are located within Brunei Bay are mostly sheltered from the South China Sea environment with little exposure if any. The effects of the exposure of the site to South China Sea at the gaps between Labuan and Sabah at the north east and between Labuan and Brunei at the west are reduced by series of islands and shallow patches lining along these gaps. Due to low tidal gradient along the coast of Sabah and northern Sarawak, tidal current along the reclamation site is weak. Like the rest of current flow along the northern coast of Sabah and Sarawak, tidal flow is towards northeast during ebb and southwest during flood. Wind generated currents are limited to the local wind generated within Brunei Bay. Based on other studies carried out around the borrow site, current speed within the proposed sand borrow site may reach 0.2 m/s. 3.2.4 Meteorology 3.2.4.1 General Climate Labuan Island is located south-west of the coast of the state of Sabah, surrounded by the South China Sea. As it is located close to the equator, the region generally Chemsain Konsultant Sdn. Bhd. Page C3-3 CK/EV403-4176/12 Detailed Environmental Impact Assessment for the Proposed Reclamation for the Development Chapter 3 of Oil and Gas Industrial Base at Kg. Rancha-Rancha, Labuan, F.T., Malaysia Existing Environment experiences an equatorial type of climate characterised by hot and humid weather all year round. The movement of the Inter-Tropical Convergence Zone (ITCZ) and the associated movement of the warm air with the monsoons influence the climate at both the reclamation and sand borrow sites. There are two distinct monsoon regimes, the North-East Monsoon from the months of November to March, and the South-West Monsoon from the months of May to September. The period between the monsoons is commonly referred to as the inter-monsoon or transition period. Data from the Malaysian Meteorological Services (MMS) Department station located at Labuan Airport (latitude 5 ° 18’ N, longitude 115 ° 15’ E, elevation 29.0 m AMSL) about 8 km to the north-eastern direction from the reclamation site is used to describe the meteorological condition of the site concerned. 3.2.4.2 Surface Winds Typical of a coastal site, the land and sea breezes have a strong influence on the behaviour of the diurnal wind. The sea breeze attains its maximum strength in the mid- afternoon in the presence of strong surface heating. It begins to weaken in the evening when the thermal difference that drives the local circulation becomes negligible. The land breeze, which normally sets during pre-dawn is much weaker with wind speeds not exceeding 5 metres/second. During times of the year when prevailing winds are light, such as the intermonsoon months, the sea breeze will play a dominant role in the transportation of pollutants at the area. Wind profile recorded at the Malaysian Meteorological Services station at Labuan Airport (approximately 8 km from the reclamation site) is depicted as annual wind rose and seasonal wind rose summaries as shown in Figure 3.2.3 and Figure 3.2.4, respectively. From the wind profile, it can be seen that the prevailing wind direction is northerly with maximum wind speed between 5.5 m/s and 7.9 m/s. Calm weather occurs about 12.8% of the time annually. During the North-East Monsoon from the months November to March, the prevailing wind direction is generally from the north and north-east with weaker winds blowing from the east and south-west. The dominant wind direction during the South-West Monsoon is from the south, south-west and west directions with weaker winds from the north and north-east. 3.2.4.3 Temperature The temperature and relative humidity data for both the reclamation and sand borrow sites are obtained from Malaysian Meteorological Services Department from year 2001 to 2010, as tabulated in Table 3.2.2. From Table 3.2.2, it can be seen that the 24-hour mean temperature ranges between 26.9 °C and 28.9 °C with an average temperature of 27.8 °C. The highest maximum temperature recorded was in the month of April 2003 at 28.9 °C while the lowest minimum temperature was in the month January 2005 at 26.9 °C. Chemsain Konsultant Sdn. Bhd. Page C3-4 CK/EV403-4176/12 Detailed Environmental Impact Assessment for the Proposed Reclamation for the Development of Oil and Gas Industrial Base at Kg. Chapter 3 Rancha-Rancha, Labuan, F.T., Malaysia Existing Environment Table 3.2.2: Records of Temperature in Labuan Island (2001-2010) Year Jan Feb Mac Apr May Jun Jul Aug Sept Oct Nov Dec Average 2001 27.3 27.4 27.7 28.2 28.9 27.7 28.6 28.5 28.0 27.4 27.2 27.4 27.9 2002 27.1 26.9 27.6 28.6 28.9 28.3 28.7 28.0 27.9 27.6 27.8 28.5 28.0 2003 27.8 27.4 27.7 28.9 28.4 28.1 27.8 28.4 28.0 27.0 27.8 27.3 27.9 2004 27.3 26.9 27.7 28.7 28.1 28.2 27.6 28.4 27.5 27.5 27.9 27.6 27.8 2005 26.9 27.7 28.0 28.8 - - - - - - - - 27.9 2006 27.6 27.7 27.6 28.3 28.4 27.7 28.7 28.1 27.6 27.6 28.6 28.1 28.0 2007 27.4 27.4 28.0 28.7 28.7 28.1 28.1 28.2 27.7 27.9 26.9 27.7 27.9 2008 27.4 26.2 27.0 27.6 27.7 27.6 27.1 27.6 27.5 27.2 27.5 27.7 27.3 2009 26.7 26.8 27.5 28.4 28.5 28.5 27.8 28.4 28.1 27.3 27.7 27.8 27.8 2010 27.1 28.0 28.2 28.4 28.6 27.8 27.4 27.8 27.5 27.7 - - 27.9 Average 27.8 Source: Malaysian Meteorological Services Department, 2010.