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LCQ13: Contractor management practices at Pillar Point Valley Landfill

     Following is a question by the Hon Steven Ho and a written reply by the Secretary for the Environment, Mr Wong Kam-sing, in the Legislative Council today (May 11):


     It was reported that the contractor for the restoration contract of the Pillar Point Valley Landfill in Tuen Mun had allegedly lowered the temperature for the flaring of landfill gas in the leachate treatment plant during the period between November last year and January this year in order to save fuel expenditure, resulting in the discharge into the sea of landfill leachate with pollutants therein not effectively eliminated (discharged water).  It has also been reported that the estimated daily discharge volume of the discharged water exceeded 800 tonnes, and the relevant water samples were found by laboratory tests to have a total nitrogen concentration over 300 milligrams/litre, exceeding the limit stipulated in the licence (i.e. 200 milligrams/litre) by more than 50 per cent.  However, the Environmental Protection Department (EPD) has pointed out that as shown by the water quality data recorded by the marine monitoring stations near the landfill from 2014 to the first two months of this year, there was no abnormality in the concentrations of inorganic nitrogen and unionized ammonia nitrogen, and the nearby coastal water and the ecological condition have all along been normal.  Some fishermen have relayed to me that the aforesaid situation reveals that there are serious loopholes in EPD's existing monitoring mechanism.  They are therefore worried that under the circumstances where it is difficult for EPD to effectively monitor the water quality of the discharged water, their health and livelihood as well as those of fish farmers and the relevant stakeholders will be dealt a further blow, and the fisheries resources will also be affected.  Regarding the monitoring of contractors' processing of landfill leachate, will the Government inform this Council:

(1) of the current procedure for processing landfill leachate, and the water quality standards to be met by the discharged water;

(2) of the working procedure adopted and the quantities of manpower and other resources deployed by the authorities in the past three years to monitor the aforesaid contractor's processing of landfill leachate; whether the authorities have assessed if it was manpower shortage, perfunctory work of public officers or mistakes in administrative procedure that resulted in their failure to detect the aforesaid malpractice of the contractor; if they have, of the relevant details;

(3) whether the authorities have studied the impacts of the aforesaid malpractice on the fisheries resources in nearby waters, as well as the losses inflicted on the fishermen, fish farmers and stakeholders concerned; if they have, of the study outcome, and how the authorities will compensate those people for their economic losses;

(4) of the respective details of the water quality data of the discharged water samples from various landfill leachate treatment plants managed by the aforesaid contractor, and the water quality data (including the concentrations of inorganic nitrogen and unionized ammonia nitrogen) recorded by the marine monitoring stations near those landfills, in the past three years;

(5) of the names of the public and private organisations responsible for managing various sewage treatment facilities (including those faciltiies involving landfills, power plants and other works), the volumes of the discharged water concerned, and the water quality data of the discharged water samples, in the past three years (setting out such information by name of the facilities);

(6) as some fishermen have relayed that the worsening water quality within Hong Kong waters in recent years has led to a decline in fish catch, whether the authorities have, in addition to monitoring over-fishing and damages to the ecological environment caused by marine works, studied the fisheries resources in various stretches of waters in Hong Kong in the past three years (with a breakdown by stretch of waters) and if the discharged water with pollutants exceeding the limits is one of the major reasons for the dwindling fisheries resources; if they have, of the study outcome; if not, the reasons for that;

(7) whether the authorities detected in the past three years that the concentration of pollutants contained in the discharged water samples was high enough to cause fishes to be poisoned to death or unfit for human consumption; and

(8) whether the authorities will step up efforts in monitoring the processing of landfill leachate by the aforesaid contractor, and whether they will review the procedure for monitoring the water quality of discharged water, so as to avoid the occurrence of similar incidents and thereby protect the fisheries resources?



     The Environment Bureau (ENB) and the Environmental Protection Department (EPD) always attach great importance to the management and supervision of our facilities' contractors, including their environmental performance to ensure full compliance with the statutory and the contractual requirements. On supervision of the landfill operation, under the prevailing mechanism, EPD on-site staffs conduct regular monitoring of the facility operation and environmental monitoring to ensure the landfill is operated in accordance with the contract requirements. The Environmental Compliance Division (ECD) of the EPD conducts inspections of the relevant facilities at irregular time intervals to check whether the facility operation is normal and in compliance with the license issued under the Water Pollution Control Ordinance (WPCO). We are deeply concerned about the earlier media reports on the contractor management practices at the Pillar Point Valley Landfill (PPVL). Our Environmental Infrastructure Division (EID)'s preliminary investigation has confirmed that the contractor has intermittently failed to meet the minimum temperature requirement to maintain a temperature of 1 000 degree Celsius for the flaring of landfill gas as set out in the contract. The EPD has consequently deducted $200,000 from this month's operation payment for the non-compliance in accordance with the relevant provision in the contract.

     Moreover, the Department has formed an investigation team to conduct a thorough investigation into the case. The investigation team has commenced the investigation work and arranged to meet with the relevant stakeholders shortly to have a thorough understanding of the case, including the complainants, the contractor, the relevant EPD staff, etc. The investigation team aims to submit a preliminary report within two months. In the case of any illegal act or breach of contract by the landfill contractor, the EPD will strictly follow up and hold the contractor accountable in accordance with the law and the contract.

     Our reply to the questions raised by the Hon Steven Ho is as follows:

(1), (2) and (8) In general, leachate collected from the landfill will be treated by the on-site leachate treatment plant in order to reduce the total nitrogen to a level meeting the corresponding discharge limits of the WPCO. The relevant limits are stipulated in the license granted to the facility under the environmental ordinance. Regarding the monitoring mechanism of landfill operation, it has been briefly discussed above. The relevant works have been subsumed under the overall staff establishment of the EID and the ECD of EPD. We do not have the detailed breakdown on the staff and resources for supervision and enforcement work for individual landfills.

     As we have emphasised, ENB and EPD attach great importance to the management of their responsible facilities. In addition to the on-going investigation on the performance of the PPVL contractor, both EID and ECD have stepped up the inspection and monitoring works, including increasing the inspection frequency of the leachate treatment plant, the nearby storm drains and stream. Water samples were collected at the leachate treatment plant and stream during the inspections. Up-to-date, no abnormality was found in our inspection of the stream, and the effluent from the leachate treatment plant has met the required license standards. In addition, we have instructed the contractor to enhance the data collection system and install CCTV to enable real time monitoring of the landfill operation and prevent data manipulation. We have also stepped up monitoring and inspection for all the leachate treatment plants at other landfills as well as publicly and privately owned treatment plants. We have also increased the sampling frequency of effluent from these facilities. Furthermore, we are reviewing the internal administration procedures and strengthening the staff training to achieve more effective management of the waste treatment facilities such that contract requirements and environmental standards can be met.

(3) The leachate from PPVL will be discharged through public sewers to the Pillar Point Sewage Treatment Works operated by the Drainage Services Department (DSD) only after treatment and meeting the license requirement in respect of the total nitrogen concentration.  Such treated leachate will be further treated and disinfected together with domestic sewage collected from the vicinity, and then discharged to the sea through a submarine outfall.  Sampling test results of the effluent of the DSD's Pillar Point Sewage Treatment Works in the respective period met the license requirements under the WPCO.

     The EPD have examined the monitoring data collected by the marine monitoring stations near the PPVL from 2014 to the first two months of this year, with the results showing no abnormality in the concentrations of inorganic nitrogen and unionised ammonia nitrogen, and that the nearby coastal water and ecological condition have been found normal. Furthermore, Agriculture, Fisheries and Conservation Department (AFCD)'s monitoring results at marine monitoring stations of Sha Chau and Lung Kwu Chau Marine Park also showed no abnormality in the concentrations of inorganic nitrogen and unionised ammonia nitrogen from November 2015 to February 2016.  These results were similar to the average concentrations recorded in 2014 and 2015. No abnormality was found in the ecological condition at the Sha Chau and Lung Kwu Chau Marine Park. In this connection, we are of the view that the fisheries resources have not been affected.

(4) The contractor of PPVL restoration contract, SITA, and its associated company, are responsible for the management of the restored PPVL, Tseung Kwan O Stage I Landfill (TKOL I), Tseung Kwan O Stage II/III Landfill (TKOL II/III), Siu Lang Shui Landfill (SLSL), Ma Tso Lung Landfill (MTLL), Ngau Tam Mei Landfill (NTML) and Gin Drinkers Bay Landfill (GDBL); and the operating North East New Territories Landfill (NENT) and West New Territories Landfill (WENT). The treated leachate discharge of these landfills had not violated the discharge limits of the WPCO in the past three years (2013-2015), details are listed in Annex 1(B).

     In respect of the water quality in the nearby marine monitoring stations of the above landfills, the nearest marine monitoring stations of PPVL and SLSL are NM2 and NM3; the nearest marine monitoring stations of TKOL I and TKOL II/III are JM3 and JM4; the nearest marine monitoring station of GDBL is VM14; the nearest marine monitoring station of MTLL and NTML is DM1; the nearest marine monitoring stations of WENT are DM5 and NM5; and the nearest marine monitoring station of NENT is MM1.

     The annual depth-averaged of Total Inorganic Nitrogen (TIN) and Unionised Ammonia (NH3-N) of the nine marine monitoring stations mentioned above for the past three years are listed in Annex 2. The water quality data showed no abnormality. Figure 1 in Annex 2 shows the locations of these marine monitoring stations.

(5) Please refer to Annex 1 for the discharge flow rates and effluent quality monitoring data of the major sewage treatment works managed by the DSD, leachate treatment plants of landfills managed by the EPD and sewage treatment facilities of power stations operated by private sector in the past three years.

(6) and (7) As shown in Annex 1, the current data of the treated effluent sample showed compliance with the license requirements. Following the implementation of trawl ban in Hong Kong waters effective from December 31, 2012, AFCD has been conducting fisheries surveys to assess the effectiveness of the trawl ban in rehabilitating the marine environment. Based on the preliminary findings from the data up to 2014, catches have increased in the south-eastern and western waters where trawling activities were relatively more intense before the implementation of the trawl ban. AFCD will continue to conduct fisheries surveys and collect more data to more thoroughly assess the effectiveness of the trawl ban in rehabilitating the marine environment.

Ends/Wednesday, May 11, 2016
Issued at HKT 17:22


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