1.                   Introduction

1.1                   Background

1.1.1                                 The existing Yuen Long Sewage Treatment Works (YLSTW) is a secondary sewage treatment works, located at Yuen Long Industrial Estate serves Yuen Long Town, Yuen Long Industrial Estate and Kam Tin areas with a design capacity of 70,000 m³ per day. Based on the latest planning data, the volume of sewage generation from the YLSTW catchment is estimated to increase to 150,000 m³ per day after 20 years. In addition, since YLSTW has been operating for over 30 years and most of its facilities are of out-dated design and reaching the end of their design life, the environmental facilities of the plant will also be upgraded and hence improving the adjacent environment through upgrading the YLSTW to Yuen Long Effluent Polishing Plant (YLEPP). The layout for construction of Yuen Long Effluent Polishing Plant (hereinafter referred as “the Project”) is given in Figure 1.

1.1.2                                 YLSTW will be reconstructed in two stages to increase its capacity to 150,000 m³ per day. The proposed works, as Stage 1 of the project, will firstly increase the treatment capacity to 100,000 m³ per day. In the course of Stage 1 construction, about half of the existing facilities of YLSTW would be demolished, while the other half would be kept in operation to maintain the sewage treatment service for Yuen Long area. The updated construction programme was presented in Appendix K.

1.1.3                                 The Project is a designated project under Schedule 2 of the Environmental Impact Assessment Ordinance (EIAO) (Cap. 499) for which Environmental Impact Assessment (EIA) report and Environmental Monitoring and Audit (EM&A) Manual was approved by EPD (Register No.: AEIAR-220/2019) on 25 April 2019. The Environmental Permit (EP) (EP No. EP-565/2019) was issued by EPD on 26 April 2019.

1.1.4                                 Fugro Technical Services Limited (FTS) has been appointed as the Environmental Team (ET) by Drainage Services Department (DSD) to undertake the Environmental Team services for the Project and implement the EM&A works under the Contract No. DC/2019/10 Yuen Long Effluent Polishing Plant -Main Works for Stage 1 (hereinafter referred as “the Contract”).

1.2                   Purpose of this Report

1.2.1                                 This purpose of this baseline report is to determine the ambient conditions of the air quality, water quality and the noise levels, and to establish the Action Levels (AL) and Limit Levels (LL) for impact monitoring during the Project implementation period. This report presents the baseline monitoring requirements, methodologies and results of baseline measurements in accordance with the requirements of the approved EM&A Manual and as stipulated in the Environmental Permit (EP) (EP No. EP-565/2019).

1.2.2                                 The baseline monitoring for air and noise were conducted between 1 December and 14 December 2020. The baseline monitoring for water was conducted between 1 December and 26 December 2020.