Metolong Water Treatment Works and Environmental
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January 2010 METOLONG WATER TREATMENT WORKS Environmental Management Plan Submitted to: Metolong Dam and Water Supply Project - MPMU Red Cross Building, 29 Mabile Street Maseru 100 REPORT Report Number: 12280-9299-2 Distribution: 6 X Metolong Dam and Water Supply Project - MPMU METOLONG WATER TREATMENT WORKS List of Acronyms AFS - Additional Feasibility Study (Mott Macdonald) CEO - Chief Executive Officer C&RAP - Compensation and Resettlement Action Plan CLA Community Liaison Assistant CMC - Catchment Management Committee CMMS - Computer-aided Maintenance Management System COD - Chemical Oxygen Demand COW - Commissioner of Water C.t - Chlorine contact time (mg/L x minutes) DAF - Dissolved Air Floatation DB - Design Build DRIFT - Downstream Response to Imposed Flow Transformation DRWS - Department of Rural Water Supply DWA - Department Water Affairs ECO - Environmental Compliance Officer EPP - Environmental Protection Plan FSL - Full Supply Level GAC - Granular Activated Carbon ICM - Integrated Catchment Management IDA - International Development Agency IFB - Invitation for Bid IFC - International Finance Corporation IFR - Instream Flow Requirement LCN - Lesotho Congress of NGOs LEC - Lesotho Electricity Corporation LWJV Lowlands Waterworks Joint Venture LLWSFS - Lowlands Water Supply Feasibility Study MCA-L - Millennium Challenge Account - Lesotho MCC - Millennium Challenge Corporation MDWSP - Metolong Dam and Water Supply Project January 2010 Report No. 12280-9299-2 i METOLONG WATER TREATMENT WORKS MNR - Ministry of Natural Resources MPIU - Metolong Project Implementation Unit MPMU - Metolong Project Management Unit NES - National Environmental Secretariat QAQC - Quality Assurance and Quality Control QAO - Quality Assurance Officer RoD - Record of Decision RP - Resettlement Plan SADC - Southern African Development Community SANS - South African National Standards SCADA - Supervisory Control and Data Acquisition SPI - Species Pollution Sensitivity Index SRP - Soluble Reactive Phosphate STIs - Sexually Transmitted Infections TRC - Transformation Resource Centre UNFCCC - United Nations Framework Convention on Climate Change WASA - Water and Sanitation Authority WATSAN - Water and Sanitation Project WTW - Water Treatment Works WWTW - Waste Water Treatment Works January 2010 Report No. 12280-9299-2 ii METOLONG WATER TREATMENT WORKS Executive Summary The Metolong Dam and Water Supply Programme (MDWSP), comprising the Metolong Dam, the Water Treatment Works (WTW) and conveyance systems, is designed to augment water supplies to the lowland towns of Lesotho by an amount of 75 Mℓ/day over and above the existing 45 Mℓ/day supplied by the Maseru water supply system. Various studies have been undertaken since 2002 that confirmed Metolong as the preferred location for the dam and the WTW. The project is rated as high priority by the Government of Lesotho (GoL). The WTW and conveyance system will be constructed with funding from the US Millennium Challenge Corporation (MCC) administered through the Millennium Challenge Account – Lesotho (MCA-L). The MCA-L appointed the Lowlands Waterworks Joint Venture (LWJV) consortium to undertake a conceptual design of the WTW and prepare tender documents for a Design-Build contract, as well as compile an Environmental and Social Impact Assessment (ESIA) and Environmental Management Plan (EMP). The ESIA and this EMP has been prepared by an independent team of sub-consultants to the LWJV. This EMP has been derived in collaboration with the development of the Invitation for Bids (IFB# WS-A-016- 09) Design-Build of Metolong WTW bidding documents (Volume 1 to Volumes IX) December 2009. This EMP provides a comprehensive overview of the mitigation and monitoring requirements for construction and operation of the proposed WTW. Adherence to these mitigation measures and management requirements will minimise the impacts of the WTW to the extent that no significant residual impact of construction or operation is likely to occur. Key tasks for implementation of the EMP during the planning and construction phases include (but are not limited to): Layout planning and compilation of detailed layout plans to ensure environmental impacts are minimised (e.g. toilets more than 50m from water courses or springs; siting of “no go” or sensitive areas such as ruins of 19th Century village, location of bunded areas, chemical stores, effluent ponds and discharge monitoring points). A stormwater layout plan designed to ensure adequate diversion and dissipation of stormwater to prevent erosion and sedimentation. Encouragement of preferential labour recruitment from the local communities to minimise social impacts associated with influx of a large labour force such as increased HIV/AIDS, increased crime, social disruption, alcoholism etc. Regular dialogue between the Contractor’s Community Relations Officer (CRO) and the Metolong Authority’s Community Relations Manager (CRM) and Community Liaison Assistants (CLAs) to keep the community abreast of work schedules and activities, and to hear and address concerns. Awareness raising and training of the workforce to ensure they are familiar with all on-site rules and requirements relating to aspects such as solid and chemical waste disposal; use of toilets; prohibition on using the veld as a toilet; for littering; trampling and harvesting of fauna and flora, or the lighting of fires. Other aspects covered include workforce awareness of communication channels and key points of contact for specific workforce issues. Implementation of the Contractor Standards for construction that are designed to mitigate erosion and sedimentation risks, pollution risks, and to manage social impacts (e.g. visual, dust/noise, blasting, January 2010 Report No. 12280-9299-2 iii METOLONG WATER TREATMENT WORKS traffic accidents etc) and other biophysical impacts (e.g. loss of flora and fauna, general habitat disturbance). Rehabilitation of disturbed areas within and around the WTW, and appropriate landscaping of the site, will minimise the visual impacts of the construction activities and the development as a whole, while minimising the risk of erosion. Auditing, monitoring, site inspections and reporting will be implemented in accordance to the EMP by the Environmental Compliance Officer (ECO), the site Engineer and the regulatory organisations such as NES, WASA, DWA etc. Key tasks for implementation of the EMP during the operational phase include: Encouragement of preferential labour recruitment from the local communities to be trained and used in the WTW. Ongoing dialogue between the CRO and the Metolong Authority’s Community Relations Manager (CRM) and CLAs to keep the community abreast of the operational issues associated with the WTW and to hear and address concerns. Awareness raising and training of the WTW workforce to ensure they are familiar with all on-site rules and requirements relating to aspects such as solid and chemical waste disposal. Other aspects covered include workforce awareness of communication channels and key points of contact for specific workforce issues. Testing of sludge produced to confirm that the preferred long-term sludge disposal solution, which is land application for soil augmentation, is environmentally acceptable. The results will be checked against guideline values specified. Monitoring of supernatant (liquid draining from the sludge) to determine whether it complies with effluent standards for disposal back to the river. If non-compliant then the supernatant will require treatment and/or dilution to meet the standards for release back to the river below the dam wall. The operator with their staff must further develop and implement a detailed Emergency Response Plan which addresses aspects such as hazardous material accidents, e.g. chlorine gas emission; compilation of an emergency contacts list; protocols for remedial action; and training of key staff to deal with incidents and accidents. Auditing, monitoring, site inspections and reporting will be implemented in accordance to the EMP by the Environmental Compliance Officer (ECO), the site Engineer and the regulatory organisations such as NES, WASA, DWA etc. January 2010 Report No. 12280-9299-2 iv METOLONG WATER TREATMENT WORKS Table of Contents 1.0 INTRODUCTION ........................................................................................................................................................ 1 1.1 Background to the Metolong Dam and Water Supply Project ....................................................................... 1 1.2 Project Team ................................................................................................................................................. 1 1.3 Objectives of this EMP .................................................................................................................................. 2 1.4 Background to this EMP ................................................................................................................................ 2 1.5 Layout of this document ................................................................................................................................ 3 2.0 PROJECT DESCRIPTION, TECHNOLOGY AND PROCESSES .............................................................................. 8 2.1 Metolong Dam and Water Supply Programme Components ........................................................................ 8 2.2 Metolong WTW components ......................................................................................................................