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LCQ14: Air quality in Tung Chung
     Following is a question by the Hon Chan Chi-chuen and a written reply by the Secretary for Environment, Mr Wong Kam-sing, in the Legislative Council today (February 22):


     In reply to a question raised by a member of this Council on January 20 last year, the authorities indicated that the air quality in Tung Chung had improved gradually between 2011 and 2015. Except for nitrogen dioxide and ozone, the air quality in Tung Chung in 2015 in terms of other air pollutants attained the relevant Air Quality Objectives (AQOs). However, recently quite a number of Tung Chung residents have relayed to me that they feel that in recent months, the air pollution problem in Tung Chung has not been alleviated but has shown signs of deterioration instead. Regarding measures to improve the air quality of Hong Kong, will the Government inform this Council:

(1) of the respective numbers of times, as recorded by the air quality monitoring station in Tung Chung last year, by which the concentrations of various pollutants (including respirable suspended particulates (i.e. PM10), fine suspended particulates (i.e. PM2.5), ozone, sulphur dioxide, nitrogen dioxide and carbon monoxide) exceeded AQOs or other relevant objectives, and the details of the exceedances of each type of pollutants, including the respective average and maximum extent of exceedance and concentrations;

(2) as the Government has, in collaboration with the Guangdong provincial authorities, set emission reduction targets to be attained in 2015 and 2020 with respect to four key types of air pollutants in the Pearl River Delta Region, and the Government is conducting a mid-term review of those targets, of the details and outcome of the work concerned; and

(3) whether it has regularly reviewed the effectiveness of the various measures for improving air quality; if so, of the outcome; if not, the reasons for that?



(1) The Environmental Protection Department is still validating the air quality monitoring data for 2016 as the year has just come to an end. According to the preliminary data on air quality for that year, three out of 16 air quality monitoring stations (AQMSs) fully attained the Air Quality Objectives (AQOs) and the Tung Chung AQMS was one of the three. From 2012 to 2016, the air quality of Tung Chung continued to improve, as the annual average concentrations of respirable suspended particulates (PM10 or RSP), fine suspended particulates (PM2.5 or FSP), ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2) dropped by 29 per cent, 25 per cent, 15 per cent, 16 per cent and 23 per cent respectively. While the annual average concentration of carbon monoxide (CO) within the same period increased by 9 per cent, both its highest 1-hour average concentration and highest 8-hour average concentration were less than 20 per cent of the respective AQO limits. The annual average concentrations of air pollutants recorded at the Tung Chung AQMS during the period are at Table 1, and a comparison of the air quality of Tung Chung in 2016 with the current AQOs is at Table 2.

(2) In 2012, the governments of Guangdong and Hong Kong set the emission reduction targets and reduction ranges for 2015 and 2020 respectively (see Table 3).  Both governments are actively implementing measures to reduce the emissions across the region. These measures can improve the air quality in the Pearl River Delta region, including alleviating the regional ozone pollution problem.

     Both governments started a mid-term review on the air pollutant emission reduction targets in February 2015 to conclude the emission reductions for 2015 and finalise the emission reduction targets for 2020. The review is expected to be completed in the first half of 2017.

(3) In recent years, the Government has undertaken a host of enhancement measures to improve air quality and the key measures are as follows:

Road Transport

(a) We launched in March 2014 an incentive-cum-regulatory scheme to phase out some 82 000 pre-Euro IV diesel commercial vehicles by the end of 2019 with $11.4 billion set aside to assist the affected vehicle owners. As at the end of 2016, the scheme retired more than 60 per cent of them;

(b) Starting from September 1, 2014, we have strengthened our vehicle emission control regime for liquefied petroleum gas (LPG) and petrol vehicles, under which roadside remote sensing equipment is deployed to screen out LPG and petrol vehicles with excessive emissions. The vehicle caught will have to pass within 12 working days an advanced emission test to confirm the rectification of the excessive emission problem. Otherwise, its vehicle licence will be cancelled;

(c) We have subsidised franchised bus companies to retrofit their Euro II and III franchised buses with selective catalytic reduction devices (SCRs) to upgrade their emission performance to Euro IV or above levels; and

(d) We have set up from December 31, 2015 franchised bus low emission zones in busy corridors in Causeway Bay, Central and Mong Kok such that franchised buses in the zones have to be low emission buses (i.e. buses meeting Euro IV or higher emission standards or the SCR-retrofitted Euro II and III buses).

Electricity Generation

     To control emissions from power plants, we have been imposing statutory emission caps on their emissions of SO2, nitrogen oxides (NOx) and RSP through the issuance of Technical Memorandums (TM) since 2008. So far, we have promulgated six TMs that progressively tightened emission caps. The latest one, which is the sixth TM, was promulgated in November 2016 to tighten the emission caps of power plants from 2021 onwards by 72 per cent, 52 per cent and 56 per cent for SO2, NOx and RSP respectively as compared with the first TM.


     The control measures for marine vessels mainly focus on the emissions of SO2 and RSP. We have capped the sulphur content of locally supplied marine light diesel at 0.05 per cent since April 2014. Since July 2015, we have also required ocean going vessels to switch to low sulphur marine fuel (with sulphur content not exceeding 0.5 per cent) while at berth.

Non-road Mobile Machinery

     A new regulation was introduced in June 2015 requiring newly imported non-road mobile machinery to comply with statutory emission standards.

     The above measures have borne fruits. From 2012 to 2016, the roadside RSP, FSP, NO2 and SO2 concentrations have a clear decreasing trend of 28 per cent, 28 per cent, 31 per cent and 30 per cent respectively. Over the same period, the ambient concentrations of RSP, FSP, NO2 and SO2 have dropped by 21 per cent, 21 per cent, 8 per cent and 18 per cent respectively, while the O3 level in general air has a slight decline of 3 per cent.

     With further implementation of the above measures, we expect that the current AQOs can be broadly attained by 2020. Meanwhile, we are reviewing the AQOs with a view to exploring new practicable air quality improvement measures and assessing the scope of tightening the AQOs made possible by their implementation. The review will be completed in 2018.
Ends/Wednesday, February 22, 2017
Issued at HKT 14:30
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