Environmental Permit No. EP-345/2009/A

                                                         環境許可證編號 EP-345/2009/A






10 13







A (許可證主要部分)


Pursuant to Section 10 of the Environmental Impact Assessment Ordinance (EIAO), the Director of Environmental Protection (the Director) granted the Environmental Permit (No. EP-345/2009) to the Water Supplies Department (hereinafter referred to as the “Permit Holder”) on 22 May 2009. Pursuant to Section 13 of the EIAO, the Director amends the Environmental Permit (No. EP-345/2009) based on the Application No. VEP-582/2020. The amendments, described below, are incorporated into this Environmental Permit (No. EP-345/2009/A). This Environmental Permit as amended is for the construction and operation of the designated project described in Part B subject to the conditions specified in Part C. The issue of this environmental permit is based on the documents, approvals or permissions described below:

根據《環境影響評估條例》(環評條例) 10條的規定,環境保護署長(署長) 2009522將環境許可證 (編號:EP-345/2009) 批予水務 (下稱許可證持有人”)根據環評條例第13條的規定,署長因應更改環境許可證的申請編號:VEP-582/2020修訂環境許可證 (編號:EP-345/2009)。以下修訂已包含在本環境許可證內 (編號:EP-345/2009/A)。本經修訂的環境許可證作為建造及營辦B 所說明的指定工程項目,但須遵守C 所列明的條件。本環境許可證的發出,乃以下表所列的文件、批准或許可作為根據


Application No.



Document in the Register:



(1)   Inter-reservoirs Transfer Scheme – Water Tunnel between Kowloon Byewash Reservoir and Lower Shing Mun Reservoir (Register No. AEIAR-135/2009) :

-          Environmental Impact Assessment Final Report [Hereinafter referred to as the “EIA Report”],

-          Executive Summary and its amended Figures 1-1 to 1-4, and

-          Environmental Monitoring and Audit Manual [Hereinafter referred to as the “EM&A Manual”]

水塘間轉運計劃 九龍副水塘至下城門水塘輸水隧道

(登記編號: AEIAR-135/2009)

-          環境影響評估終期報告[下稱環評報告]

-          行政摘要和其已修改的圖1-11-4,以及

-          環境監察及審核手冊[下稱環監手冊]


(2) The Director’s letter of approval of the EIA Report dated 15 April 2009 (Reference: (12) in EP2/N1/Q/45 Pt.2)

署長於20094 15 發出批准環評報告的信件 (檔案編號:(12) in EP2/N1/Q/45 Pt.2)


(3) Application for Environmental Permit submitted on 27 April 2009 (Application No. AEP-345/2009)

2009427 提交的環境許可證申請文件 (申請書編: AEP-345/2009)


(4) Environmental Permit issued on 22 May 2009 (Permit No. EP-345/2009)

2009522日簽發的環境許可證 (許可證編號EP-345/2009)


(5) Application for Variation of Environmental Permit submitted on 15 October 2020 (Application No. VEP-582/2020)

20201015日提交的更改環境許可證申請文件 (申請書編號:VEP-582/2020)


Application No.



Date of Application


List of Amendments Incorporated into this Environmental Permit



Date of Amendment




15 October 2020



-    Vary “Location of Designated Project” in Part B of the Environmental Permit (No. EP-345/2009)

更改環境許可證(編號EP-345/2009) B指定工程項目的地點


-    Vary Conditions 1.7, 3.1, 3.3, 3.7, 3.9, and 3.10 in Part C of the Environmental Permit (No. EP-345/2009)

更改環境許可證(編號EP-345/2009) C條件第1.7, 3.1, 3.3, 3.7, 3.93.10



-    Vary Figures 1, 2 and 3 of the Environmental Permit (No. EP-345/2009)

更改環境許可證(編號EP-345/2009) 12 3


-    Add Figures 4, 5 and 6 to the Environmental Permit (No. EP-345/2009)

在環境許可證(編號EP-345/2009) 加入456

11 November 2020








         11 November 2020





(Sunny C.W. CHEUNG)

Principal Environmental Protection Officer

for Director of Environmental Protection


(首席環境保護主任 張展華 代行)


B (指定工程項目的說明)


Hereunder is the description of the designated project mentioned in Part A of this environmental permit (hereinafter referred to as the “Permit”):

下列為本環境許可證 (下稱許可證) A 所提的指定工程項目的說明


Title of Designated Project


Inter-reservoirs Transfer Scheme – Water Tunnel between Kowloon Byewash Reservoir and Lower Shing Mun Reservoir

[This designated project is hereafter referred to as “the Project”]

水塘間轉運計劃 九龍副水塘至下城門水塘輸水隧道

[本指定工程項目下稱 工程項目”]


Nature of Designated Project

Project including earthworks partly in Kam Shan Country Park



Location of Designated Project


Project with alignment from Kowloon Byewash Reservoir to Lower Shing Mun Reservoir. The location of the Project is shown in Figure 1 of this Permit.



Scale and Scope of Designated Project


A water tunnel, of approximately 2.8 km in length and 3m in diameter, with intake at Kowloon Byewash Reservoir and outfall at Lower Shing Mun Reservoir.







C (許可證條件)


1.         General Conditions



1.1       The Permit Holder and any person working on the Project shall comply with all conditions set out in this Permit. Any non-compliance by any person may constitute a contravention of the Environmental Impact Assessment Ordinance (EIAO) (Cap. 499) and may become the subject of appropriate action being taken under the EIAO.

許可證持有人及任何從事工程項目的人士必須完全符合本許可證載列的全部條件。任何人士如有不符合本許可證的情況,可能違反《環境影響評估條例》(環評條例) (499) 的規定,而當局可根據環評條例採取適當行動。


1.2       The Permit Holder shall ensure full compliance with all legislation from time to time in force including, without limitation to, the Noise Control Ordinance (Cap. 400), Air Pollution Control Ordinance (Cap. 311), Water Pollution Control Ordinance (Cap. 358), Dumping at Sea Ordinance (Cap. 466) and Waste Disposal Ordinance (Cap. 354). This Permit does not of itself constitute any ground of defence against any proceedings instituted under any legislation or imply any approval under any legislation.

許可證持有人須確保完全符合現行法例的規定,包括但不限於《噪音管制條例》(400) 、《空氣污染管制條例》(311)、《水污染管制條例》(358) 、《海上傾倒物料條例(466) 及《廢物處置條例》(354)。本許可證本身不會就根據任何法例提的法律程序構成任何抗辯理由,或根據任何法例默示任何批准。


1.3       The Permit Holder shall make copies of this Permit together with all documents referred to in this Permit and the documents referred to in Part A of this Permit readily available at all times for inspection by the Director or his authorised officers at all sites covered by this Permit. Any reference to this Permit shall include all documents referred to in this Permit and also the relevant documents in the Register.

許可證持有人須印製本許可證的複本,連同本許可證所述的所有文件及本許可證A 所述文件,以供署長或獲授權人員任何時間內在本許可證所涵蓋的所有工地查閱。凡提述本許可證,須包括本許可證所述的所有文件及登記冊內的相關文件。


1.4       The Permit Holder shall give a copy of this Permit to the person(s) in charge of the site(s) and ensure that such person(s) fully understands all conditions and all requirements incorporated in this Permit. The site(s) refers to site(s) of construction and operation of the Project and shall mean the same hereafter.



1.5       The Permit Holder shall display conspicuously a copy of this Permit on the construction site(s) at all vehicular site entrances/exits or at a convenient location for public’s information at all times. The Permit Holder shall ensure that the most updated information about this Permit, including any amended Permit, is displayed at such locations. If the Permit Holder surrenders a part or the whole of this Permit, the notice he sends to the Director shall also be displayed at the same locations as the original Permit. The suspended, varied or cancelled Permit shall be removed from display at the construction site(s).



1.6       The Permit Holder shall construct and operate the Project in accordance with the project description in Part B of this Permit.



1.7       The Permit Holder shall ensure that the Project is constructed and operated in accordance with the information and recommendations described in the EIA Report (Register No. AEIAR-135/2009); the application documents for environmental permits; other relevant documents in the Register; the information and mitigation measures described in this Permit; mitigation measures to be recommended in submissions that shall be deposited with or approved by the Director as a result of permit conditions contained in this Permit; and mitigation measures to be recommended under on-going surveillance and monitoring activities during all stages of the Project. Where recommendations referred to in the documents of the Register are not expressly referred to in this Permit, such recommendations are nevertheless to be implemented unless expressly excluded in this Permit or otherwise agreed by the Director.



1.8       All submissions, as required under this Permit, shall be rectified and resubmitted in accordance with the comments, if any, made by the Director within one month of the receipt of the Director’s comments or otherwise as specified by the Director.



1.9       All submissions approved by the Director, all submissions deposited without comments by the Director, or all submissions rectified in accordance with comments by the Director under this Permit shall be construed as part of the permit conditions described in Part C of this Permit. Any variation of the submissions shall be approved by the Director in writing or as prescribed in the relevant permit conditions. Any non-compliance with the submissions may constitute a contravention of the Environmental Impact Assessment Ordinance (Cap. 499). All submissions or any variation of the submissions shall be verified by the Independent Environmental Checker (IEC) referred to in Condition 2.1 below, before submitting to the Director under this Permit.



1.10     The Permit Holder shall release all finalised submissions as required under this Permit, to the public by depositing copies in the EIAO Register Office, or in any other places, or any internet websites as specified by the Director, or by any other means as specified by the Director for public inspection. For this purpose, the Permit Holder shall provide sufficient copies of the submissions.



1.11     All submissions to the Director required under this Permit shall be delivered either in person or by registered mail to the EIAO Register Office (currently at 27/F, Southorn Centre, 130 Hennessy Road, Wanchai, Hong Kong). Electronic copies of all finalized submissions required under this Permit shall be prepared in Hyper Text Markup Language (HTML) (version 4.0 or later) and in Portable Document Format (PDF version 4.0 or later), unless otherwise agreed by the Director and shall be submitted at the same time as the hard copies.



1.12     The Permit Holder shall notify the Director in writing the commencement date of construction of the Project at least two weeks prior to the commencement of construction of the Project. The Permit Holder shall notify the Director in writing immediately if there is any change of the commencement date of the construction.



1.13     For the purpose of this Permit, “commencement of construction” does not include works related to site clearance and preparation, or other works as agreed by the Director.




2.         Submissions and Measures for Commencement of Construction of the Project



            Employment of environmental monitoring and audit personnel


2.1       An Independent Environmental Checker (IEC) shall be employed no later than one month before the commencement of construction of the Project. The IEC shall have at least 7 years’ experience in environmental monitoring and auditing (EM&A) or environmental management. The IEC shall audit the overall EM&A programme including the implementation of all environmental mitigation measures, submissions relating to EM&A, and any other submissions required under this Permit. In addition, the IEC shall be responsible for verifying the environmental acceptability of permanent and temporary works, relevant design plans and submissions under this Permit.



2.2       An Environmental Team (ET) shall be established no later than one month before the commencement of construction of the Project. The ET shall be headed by the ET Leader who shall have at least 7 years’ experience in EM&A or environmental management. The ET and the ET Leader shall be responsible for the implementation of the EM&A programme in accordance with the relevant EM&A requirements as contained in the EM&A Manual.



2.3       The Permit Holder shall, within one month after the commencement of construction of the Project, inform the Director in writing of the management organization for the construction of the Project. The submitted information shall include at least an organization chart, names of responsible persons and EM&A personnel, and their contact details.



            Submission of Landscape Plan


2.4       The Permit Holder shall submit 3 sets of a Landscape Plan, together with Tree Removal Proposal, to the Director for approval no later than 6 months after commencement of construction of the Project. Construction works on wooded areas shall only be carried out after the Director’s approval of the Landscape Plan.



2.5       The Landscape Plan shall include the locations, design details, implementation programme (including the programme for any tree transplantation work), maintenance and management schedules, and drawings in the scale of 1:1000 or other appropriate scales to show the relevant mitigation measures (including any hard and soft works and finishes) recommended in the EIA report. It shall take into account the requirements in Conditions 3.3, 3.4 and 3.5 of this Permit. The Landscape Plan and Tree Removal Proposal shall be certified by the ET Leader and verified by the IEC.

            景觀美化計劃須包括涵蓋位置、設計詳情、實施計劃(包括任何樹木移植工程的計劃)、保養及管理時間表,以及比例為1:1000 或其他合適比例繪畫的圖則,以展示環評報告建議的有關緩解措施(包括任何美化環境和種植花木的工程,以及終飾)。景觀美化計劃須考慮本許可證條件第3.33.43.5項的規定。景觀美化計劃及移走樹木建議書須由環境小組組長核證及獨立環境查核人核實。


            Submission of condition survey report for historic structures


2.6       The Permit Holder shall carry out a condition survey as required in the EM&A Manual for Kowloon Byewash Reservoir Dam and Valve House, Shek Lei Pui Northeast Dam and Valve House, and Shek Lei Pui Southwest Dam, and deposit with the Director a condition survey report before the commencement of construction of the Project. Recommendation on the necessity for monitoring measures and any additional protective measures, and the details of the recommended measures, shall be provided in the condition survey report. The condition survey report shall be submitted to Antiquities and Monuments Office for review, certified by the ET Leader and verified by the IEC. The Permit Holder shall implement the recommendations of the condition survey report as part of the EM&A programme under Condition 4.1 of this Permit.




3.         Measures during Construction of the Project



3.1       The Permit Holder shall construct the Project in accordance with the locations shown in Figures 1 to 6 of this Permit.



            Measures to mitigate impact on country park and natural environment


3.2       The designs and measures described in the approved Landscape Plan submission under Condition 2.4 of this Permit shall be fully implemented under the supervision of a Registered Landscape Architect, assisted by a qualified ecologist.



3.3       Plant species of conservation importance including Pavetta hongkongensis, Artocarpus hypargyreus, Aquilaria sinensis, Diospyros vaccinioides, Enkianthus quinqueflorus and Gnetum luofuense found within the Project worksites and along the temporary access shall be preserved in-situ as far as possible. If it is impracticable to preserve individual plants in-situ due to site constraints, transplantation and/or compensatory planting shall be implemented as recommended in the EIA Report and/or the application documents for variation of environmental permit (Application No.: VEP-582/2020).



3.4       For compensatory planting, the compensatory ratio shall not be less than 1:2 in term of area and in term of number of trees to be felled.

            進行補償種植時,按面積及計劃砍伐的樹木數量計算,補償種植比例須不低於 1 2


3.5       Decorative screen hoarding compatible with surrounding setting shall be erected along the land boundary of the worksite areas to minimize disturbance to adjacent environment.



3.6       The Permit Holder shall prohibit eating, leaving food and feeding the wildlife in the works areas.



3.7       Fish observed remaining at the works area during the draining down process shall be translocated to the portion of the reservoir outside the cofferdam/earth bund as stated in Condition 3.10 of this Permit.

            在放乾工地過程期間,所發現剩餘在工地範圍內的魚類,須遷移至本許可證條件第 3.10 項所述的圍堰/土堤以外的水塘部分。


3.8       Litter shall not be burned on-site but shall be removed off-site. Machinery not in use shall be switched off to minimize the noise disturbance to natural surroundings.



            Measures to mitigate impact on reservoirs and water gathering grounds


3.9       Desilting facilities shall be constructed at intake and outfall portals to control discharge of suspended solids during construction of the Project. The desilting facilities shall be constructed within the temporary cofferdam/earth bund that are for pumping dry the worksites.



3.10     The Permit Holder shall construct the temporary cofferdam/earth bund at the intake and outfall portals as recommended in the application documents for variation of  environmental permit (Application No.: VEP-582/2020) and as shown in Figures 2 and 3 of this Permit. The cofferdam/earth bund shall be watertight enclosures. They shall be regularly inspected and maintained to ensure no spillage of waste or wastewater into the reservoirs. If there is any change to the temporary cofferdam/earth bund, such as location, design, and/or construction and demolition methods, the Permit Holder shall, prior to implementation of such changes, submit a Water Quality Protective Measures Plan to the Director for approval.

            許可證持有人須按更改環境許可證申請文件申請書編號:VEP-582/2020所建議本許可證23 所示在進水口及排水口興建臨時圍堰/土堤。圍堰/土堤須為防滲水的圍封物,並須定期進行檢查及維修保養,以確保廢物或廢水不會濺溢至水塘。倘若臨時圍堰/土堤有任何,例如位置設計/或建造及拆卸方法,許可證持有人須在進行任何改向署提交水質保護措施計劃以供批准


3.11     The water quality mitigation measures and site management practices as specified in Appendix A of this Permit to minimize water quality impact shall be implemented. Site surveillance on the measures as stipulated in Section 9.1 of the EM&A Manual shall be carried out as part of the EM&A programme under Condition 4.1 of this Permit.



            Measures to avoid hazard to life


3.12     The Permit Holder shall exclude the use of explosives for tunneling works of the Project. No blasting operation shall be permitted.



3.13     The Permit Holder shall ensure that the operation of Shek Lei Pui Water Treatment Works (SLPWTW) is suspended and that all chlorine drums are removed from SLPWTW before commencement of construction of the Project.




4.         Environmental Monitoring and Audit Requirements



4.1       An EM&A programme shall be implemented in accordance with the procedures and requirements as set out in the approved EM&A Manual of the Project. Any changes to the programme shall be justified by the ET Leader and verified by the IEC as conforming to the information and requirements contained in the EM&A Manual before submitting to the Director for approval.



4.2       Three hard copies of the Baseline Monitoring Report and one electronic copy shall be submitted to the Director at least two weeks before commencement of construction of the Project. The submission shall be certified by the ET Leader and verified by the IEC. Additional copies of the submission shall be made available to the Director upon his request.



4.3       Three hard copies of monthly EM&A Reports and one electronic copy shall be submitted to the Director within 2 weeks after the end of the reporting month. The submission shall be certified by the ET Leader and verified by the IEC. Additional copies of the submission shall be made available to the Director upon his request.




5.         Electronic Reporting of EM&A Information



5.1       To facilitate public inspection of the Baseline Monitoring Report and monthly EM&A Reports via the EIA Ordinance Internet Website and at the EIA Ordinance Register Office, electronic copies of these reports shall be prepared in Hyper Text Markup Language (HTML) (version 4.0 or later) and in Portable Document Format (PDF version 1.3 or later), unless otherwise agreed by the Director, and shall be submitted at the same time as the hard copies. For HTML version, a content page capable of providing hyperlink to each section and sub-section of the reports shall be included in the beginning of the document. Hyperlinks to all figures, drawings and tables in these reports shall be provided in the main text from where the respective references are made. All graphics in the reports shall be in interlaced GIF format unless otherwise agreed by the Director. The content of the electronic copies of these reports shall be the same as the hard copies.





1.         This Permit consists of three parts, namely, Part A (Main Permit), Part B (Description of Designated Project) and Part C (Permit Conditions). Any person relying on this Permit should obtain independent legal advice on the legal implications under the EIAO, and the following notes are for general information only.

本許可證共有3部,即 A (許可證主要部分)B (指定工程項目的說明) C (許可證條件)。任何援引本許可證的人士須就環評條例的法律含意徵詢獨立法律意見,下述註解只供一般參考用。


2.         If there is a breach of any condition of this Permit, the Director or his authorized officer may, with the consent of the Secretary for the Environment, order the cessation of associated work until the remedial action is taken in respect of the resultant environmental damage, and in that case the Permit Holder shall not carry out any associated works without the permission of the Director or his authorized officer.



3.         The Permit Holder may apply under Section 13 of the EIAO to the Director for a variation of the conditions of this Permit. The Permit Holder shall replace the original permit displayed on the Project site by the amended permit.



4.         A person who assumes the responsibility for the whole or a part of the Project may, before he assumes responsibility of the Project, apply under Section 12 of the EIAO to the Director for a further environmental permit.



5.         Under Section 14 of the EIAO, the Director may with the consent of the Secretary for the Environment, suspend, vary or cancel this Permit. The suspended, varied or cancelled Permit shall be removed from display at the Project site.



6.         If this Permit is cancelled or surrendered during construction or operation of the Project, another environmental permit must be obtained under the EIAO before the Project could be continued. It is an offence under Section 26(1) of the EIAO to construct or operate a designated project listed in Part I of Schedule 2 of the EIAO without a valid environmental permit.



7.         Any person who constructs or operates the Project contrary to the conditions in this Permit, and is convicted of an offence under the EIAO, is liable:


(i)                 on a first conviction on indictment to a fine of $2 million and to   imprisonment for 6 months;

(ii)               on a second or subsequent conviction on indictment to a fine of $5 million and to imprisonment for 2 years;

(iii)             on a first summary conviction to a fine at level 6 and to imprisonment for 6 months;

(iv)             on a second or subsequent summary conviction to a fine of $1 million and to imprisonment for 1 year; and

(v)               in any case where the offence is of a continuing nature, the court or magistrate may impose a fine of $10,000 for each day on which he is satisfied the offence continued.




(i)     一經公訴程序首次定罪,可處罰款200萬元及監禁6個月;

(ii)               一經公訴程序第二次或其後每次定罪,可處罰款500萬元及監禁2年;

(iii)             一經簡易程序首次定罪,可處第6級罰款及監禁6個月;

(iv)             一經簡易程序第二次或其後每次定罪,可處罰款100萬元及監禁1年;

(v)               在任何情況下如該罪行屬持續性質,法院或裁判官可就其信納該罪行持續的每天另處罰款10,000元。


8.         The Permit Holder may appeal against any condition of this Permit under Section 17 of the EIAO within 30 days of receipt of this Permit.



9.         The Notes are for general reference only and that the Permit Holder should refer to the EIAO for details and seek independent legal advice.




Environmental Permit No. EP-345/2009/A

環境許可證編號  EP-345/2009/A

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Appendix A (as referred to in Condition 3.11)

附錄A  (條件第3.11項所述)


Measures to minimize water quality impact on reservoirs and water gathering grounds



Mitigations for point and non-point sources


(i)                Construction runoff shall be managed as per the Practice Note for Professional Persons ProPECC PN 1/94 – Construction Site Drainage and the conditions of working within Water Gathering Grounds stipulated by Water Supplies Department.

建築工地的徑流必須根據專業人士專業守則 (ProPECC PN 1/94) - 建築工地排水的規定,以及水署有關集水區的工作條件規定作出處理。


(ii)              A Drainage Management Plan shall be prepared by the Contractor for approval by the Engineer for each of the works areas, detailing the facilities and measures to manage pollution arising form surface runoff from those works areas.



(iii)            An Emergency Contingency Plan shall be prepared by the Contractor, detailing the response and procedures to contain and remove any accidental spillage along the temporary and permanent roads and at the site at short notice to prevent or minimize the quantities of contaminants from reaching the reservoirs and local streams leading to the reservoirs. The Emergency Contingency Plan should be submitted to the Engineer for approval.



(iv)            Surface run-off and effluent from the construction sites at the tunnel intake and outfall will be directed towards adequately designed sand/silt removal facilities such as sand/silt traps and sediment basins to remove sand/silt particles from runoff before discharging to discharge points downstream of the Kowloon Byewash Reservoir Dam and Lower Shing Mun Reservoir Dam respectively. The design of efficient silt removal facilities shall be based on the guidelines in Appendix A1 of ProPECC PN 1/94, which states that the retention time for silt/sand traps should be 5 minutes under maximum flow conditions. Sizes may vary depending upon the flow rate, but for a flow rate of 0.1m3/s a sedimentation basin of 30m3 would be required and for a flow rate of 0.5 m3/s the basin would be 150 m3. The detailed design of the sand/silt traps shall be undertaken by the contractor prior to the commencement of construction.

隧道入水口及排水口建造工地的地面徑流及污水,須流經妥為設計的泥沙 / 淤泥清除設施 (如隔沙池、隔泥池及沉澱池),隔除徑流的泥沙 / 淤泥微粒,然後才排入分別位於九龍副水塘及下城門水塘下游的排放點。污水淤泥清除設施的設計,必須根據專業人士專業守則 (ProPECC PN 1/94)附錄A1的指引。有關指引述明,在最高流量的情況下,隔沙/泥池的滯水時間為5分鐘。隔沙/泥池的面積可因應流量而有異。如流量為每秒0.1立方米,沉澱池須為30立方米;如流量為每秒0.5立方米,則沉澱池須為150立方米。承辦商須於工程展開前負責有關隔沙/泥池的詳細設計。


(v)              Channels, earth bunds or sand bag barriers shall be provided on-site to properly direct stormwater to the above-mentioned facilities.



(vi)            Existing on-site silt removal facilities, channels and manholes, if any, shall be maintained and the deposited silt and grit should be removed regularly, at the onset of and after each rainstorm to ensure that these facilities are functioning properly at all times.



(vii)          Other manholes, if any, including any newly constructed ones shall be adequately covered and temporarily sealed so as to prevent silt, construction materials or debris from getting into the drainage system.



(viii)        Open stockpiles of materials on site shall be avoided within water gathering grounds as far as practicable. All surplus spoil shall be removed from water gathering grounds as soon as possible. Measures shall be taken to prevent the washing away of construction materials, soil, silt or debris.



(ix)            Where possible, works entailing soil excavation will be minimized during the rainy season (i.e. April to September). If excavation in soil could not be avoided in these months or at any time of year when rainstorms are likely, for the purpose of preventing soil erosion, temporary exposed slope surfaces should be covered e.g. by tarpaulin, and temporary access roads should be protected by crushed stone or gravel, as excavation proceeds. Intercepting channels shall be provided (e.g. along the crest/edge of excavation) to prevent storm runoff from washing across exposed soil surfaces. Arrangements shall always be in place to ensure that adequate surface protection measures can be safely carried out well before the arrival of a rainstorm.



(x)              Where applicable, final earthworks surfaces/ slopes shall be well compacted and hydro-seeded following completion to prevent erosion.



(xi)            For petrol interceptor petrol for surface runoff or construction effluent likely to be contaminated with oil, detailed design of the petrol interceptor shall be provided by the Contractor before commencement of construction. Oil leakage or spillage shall be contained and cleaned up immediately.



(xii)          Sewage arising from the construction workers on site shall be collected by temporary sanitary facilities e.g. portable chemical toilets. Portable toilets shall be used coupled with tankering away services provided by a licensed collector.



(xiii)        Vehicle wheel washing facilities shall be provided, where applicable, at the site exit such that mud, debris, etc. deposited onto the vehicle wheels or body can be washed off before the vehicles are leaving the site area.



(xiv)        Section of the road between the wheel washing bay and the public road shall be paved with backfill to reduce vehicle tracking of soil and to prevent site run-off from entering public road drains.



(xv)          Vehicle washing facilities shall be drained into desilting facilities before discharge. The water shall be recycled or reused on site wherever possible.



(xvi)        Desilting facilities shall be checked and the deposited silt and grit shall be removed regularly to ensure they are working properly at all times.



(xvii)      To minimize water quality impact, recycled water shall be used at the cutter face for cooling purposes. Used water shall be collected and discharged to settling tank for settlement



(xviii)    Excess water from the settling tank shall be transferred to the desilting facilities for treatment before discharge.



Protection against accidental spillage



(xix)        All fuel tanks and storage of chemical wastes shall be sited on sealed and bunded areas, provided with locks, and located outside water gathering grounds as far as practicable.



(xx)          The storage areas shall be surrounded by bunds with a capacity equal to 110% of the storage capacity of the largest tank to prevent accidentally spilled oil, fuel or chemicals from reaching the receiving waters.



(xxi)        Oil and grease removal facilities shall be provided where appropriate, for example, in area near plant workshop/ maintenance areas, if any.