2.      INTRODUCTION

2.1         The Project ‘HATS Stage 2A - Upgrading works at Stonecutters Island Treatment Works – Main Pumping Station, Sedimentation Tanks and Ancillary Facilities’ under Contract No: DC/2009/10 mainly comprises the construction of a large underground pumping station with an internal diameter of 55 metres and a depth of more than 40 metres, the provision of additional double-tray sedimentation tanks, a new computer control system, the expansion and modification of existing installations of the SCISTW as well as the construction of other ancillary facilities. The general location plan of the Project is shown in Figure 1.

2.2         The Project is under Harbour Area Treatment Scheme (HATS) Stage 2A and is a designated project with Register No. : AEIAR-121/2008. The current works under the Project and other Contracts at SCISTW for HATS 2A are covered by the same Environmental Permit (Permit No. EP-322/2008/G), which was issued on 9th May 2014 by the Environmental Protection Department (hereinafter called EPD) to the Drainage Services Department (hereinafter called the DSD) as the Permit Holder.

2.3         Sun Fook Kong -Biwater Joint Venture (hereafter called the SBJV) was commissioned by the DSD to undertake the construction of the Contract No. DC/2009/10 “HATS 2A –Upgrading works at Stonecutters Island Treatment Works – Main Pumping, Sedimentation Tanks and Ancillary Facilities”. The commencement date of the Project's construction was 24th February 2011.

2.4         As part of the planned construction programme, a 2-weeks duration of temporary sewage bypass is required for the construction of the interconnection between the two main pumping stations at SCISTW and other modification works to the pumping stations, which are targeted to take place during the non-bathing season(November to February) between the years 2015/16 or 2016/17. During this period the effluent will be bypassed via the HATS Stage 1 PTWs to facilitate these construction works under Contract No. DC/2009/10.

2.5         Baseline water quality monitoring was conducted on 22 November 2014, 13 December 2014 and 24 January 2015, once per month for three consecutive months at all selected monitoring stations prior to the commencement of temporary sewage bypass construction work mentioned in Sections 2.3 and 2.4.

Purpose of the Report

2.6         The purpose of this Baseline Water Quality Monitoring Report is to establish the baseline conditions for various water quality parameters in the vicinity of the project site. These baseline levels will be used as the basis for the impact and post-impact monitoring. This report presents the monitoring locations, equipment, period, methodology, results and observations for the water quality measurements during the baseline period.