7                LANDFILL GAS MONITORING

Monitoring Requirement

7.1          In accordance with the updated EM&A Manual, monitoring of landfill gas (LFG) is required for the construction works within the Ma Tso Lung Landfill (MTLL, close to KTN NDA) during the construction phase. This section presents the results of landfill gas measurements performed by the Contractor. Appendix B shows the Limit Levels for the monitoring works.

 

7.2          The MTLL is situated in the vicinity of the KTN NDA. A portion of the development falls within the MTLL and its 250m Consultation Zone.

Monitoring Parameters and Frequency

7.3          Monitoring parameters for Landfill gas monitoring include Methane, Carbon dioxide and Oxygen.

7.4          According to the mitigation measures of the updated EM&A Manual, measurements of the following frequencies should be carried out according to the monitoring requirements and procedures specified in Paragraphs 8.23 to 8.28 of EPD's Guidance Note, “LANDFILL GAS HAZARD ASSESSMENT GUIDANCE NOTE”.

7.5          The frequency of monitoring of LFG was made reference to the updated EM&A Manual - Monitoring of any LFG which may be migrated to the site should be undertaken during construction of the infrastructure and the development within the Consultation Zone and within MTLL when the works involve confined spaces. Routine gas monitoring should be undertaken during groundwork construction and in all excavations. Monthly gas monitoring should also be conducted for set up on site such as offices, stores etc.

Monitoring Locations

7.6          Monitoring of oxygen, methane and carbon dioxide was performed for the construction of infrastructure and the development within the Consultation Zone and within MTLL when the works involved confined spaces.  In this reporting month, the area required to be monitored for landfill gas are shown below and Figure 6 shows the landfill gas monitoring locations.

Ø   Excavation Locations:                       Portion 6b

Ø   Manholes and Chambers:                  N/A

Ø   Relocation of monitoring wells:        N/A

Ø   Any other Confined Spaces:             Containers in Portion 6b

Monitoring Equipment

7.7          Table 7.1 summarises the equipment employed by the Contractor for the landfill gas monitoring.

 

Table 7.1    Landfill Gas Monitoring Equipment

Equipment

Model and Make

Quantity

Portable gas detector

Rasi 700 BIO

 (Serial No. 330055)

1

       Results and Observations

7.8          In the reporting month, landfill gas monitoring was carried out by the Contractor on 1 occasion at 6 monitoring stations.  No Limit Level exceedance for landfill gas monitoring was recorded in the reporting month. The monitoring results are provided in Appendix J. Copies of calibration certificates are attached in Appendix C.

Event and Action Plan

7.9          Should any non-compliance of the criteria occur, actions in accordance with the Event/Action Plan in Appendix N would be carried out.