Environmental Guidance Note for Sewage Pumping Stations which is not a Designated Project
5. Environmental Criteria to be Complied With
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Odour |
| 5.1 |
Predicted odour nuisance at air sensitive receivers should not be greater than the guideline of 5 odour units based on an average time of 5 seconds. An odour within the guideline should not normally cause nuisance. Odour unit is defined as the dilution factor that is required for samples of odourous gases to be diluted with clean odour-free air to achieve the detection threshold. Measurement of odour can also be expressed in terms of Hydrogen Sulphide (H2S) concentration, and the equivalent detection threshold criterion (1 odour unit) is 0.00047 ppm by volume or 0.00066 mg/m3. |
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Construction Dust |
| 5.2 |
During the construction stage, the Air Quality Objectives for total suspended particulates (TSP) and respirable suspended particulates (RSP) established under the Air Pollution Control Ordinance at air sensitive receivers should be met. The hourly TSP concentration at affected air sensitive receivers should not exceed the guideline of 500ug/m3 per hour. |
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Noise |
| 5.3 |
In order to plan for a better environment, fixed noise sources associated with the sewage pumping station should be so located and designed that when assessed in accordance with the "Technical Memorandum for the Assessment of Noise from Places other than Domestic Premises, Public Places or Construction Sites" (TM) published under the Noise Control Ordinance, the level of intruding noise at the facade of the nearest sensitive uses should be at least 5 dB(A) below the appropriate Acceptable Noise Level (ANL) shown in Table 2 of the TM or, in the case of the background noise level being 5 dB(A) lower than the TM, should not be higher than the background. |
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Water |
| 5.4 |
The Water Pollution Control Ordinance (WPCO), which was enacted in 1980, governs the control of water quality in Hong Kong. During normal operation, there should be no discharge from the sewage pumping station. |
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Waste Disposal |
| 5.5 |
Disposal of screenings and sludge arising from a sewage pumping station during operation should be to one of the strategic landfills for the time being. [Note : In the long term, according to the "Sludge Treatment and Disposal Strategy Study", a sludge treatment facility is proposed to handle the sludge.] |
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| 5.6 |
Disposal of chemical waste should follow the requirements stipulated in the Waste Disposal (Chemical Waste) (General) Regulation. |
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Conservation and Tree Preservation |
| 5.7 |
During the planning of the sewage pumping station, HKPSG Chapter 10 "Conservation" should be taken into account. There is a general presumption against development within declared areas of conservation use. Efforts should be made to protect and preserve cultural heritage. Sewage pumping stations should be suitably sited to conserve, as far as practicable, the natural landscape. |
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| 5.8 |
The project limit must not encroach on recognized sites of conservation importance, or within 150m of a Site of Special Scientific Interest. Potential important habitats and species of conservation importance should not be affected. (Note : The recognized sites of conservation importance, important habitats and species of conservation importance are listed in Annex 16 of the Technical Memorandum on Environmental Impact Assessment Process.) |
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| 5.9 |
During the planning, design and construction of the sewage pumping station, ETWB Technical Circular (Works) No. 3/2006 "Tree Preservation" should be taken into account. It is policy to ensure that no trees are unnecessarily lopped or felled. Where tree felling is unavoidable, compensatory landscaping/replanting may be required. |
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