4.        WATER QUALITY

Monitoring Requirements

4.1              Water quality monitoring was conducted in accordance with the Updated EM&A Manual.  Compliance Levels for the environmental monitoring works are shown in Appendix A.

Monitoring Equipment

4.2              Table 4.1 summarizes the equipment used in the water quality monitoring program.  All the monitoring equipments complied with the specifications stipulated in the Updated EM&A Manual.  Calibrations of equipments are conducted quarterly. Copies of renewed calibration certificates for the reporting month are attached in Appendix B.

 

Table 4.1     Water Quality Monitoring Equipment

Equipment

Model and Make

Qty.

Multi-parameter Water Quality System

YSI 6820

2

Monitoring Position Equipment

“Magellan” Handheld GPS Model GPS-320

1

Monitoring Parameters, Frequencies and Durations

4.3              Table 4.2 summarizes the monitoring parameters, monitoring periods and frequencies of water quality monitoring. The water quality monitoring schedule for this reporting period is shown in Appendix C.

Table 4.2     Water Quality Monitoring Parameters and Frequencies

Monitoring Station

Parameters

Frequencies

W1

DO, Turbidity, pH, NH4-N and Temperature

Once per week during mid ebb

W2.1, W2.2 (Before 6/7/04)

DP1-DP8

(After 6/7/04)

pH and Temperature

Once per week (during mid ebb at ultimate discharge)

COD and SS

Once per month (during mid ebb at ultimate discharge)

Monitoring Locations

4.4              The Updated EM&A Manual specifies one water quality monitoring location for mixing zone of YLBF and Kam Tin River. Other monitoring locations for site discharges will follow the actual discharge locations for the reporting month. Table 4.3 describes the location of these monitoring stations.  According to ET’s facsimile (Ref.: MA2049/Corres/Out/an40706v2), the monitoring locations of W2.1 and W2.2 were relocated on 6 July 2004. The revised monitoring locations were shown in Figure 4.1.

 

Table 4.3     Location for Impact Water Quality Monitoring Stations

Monitoring Station

Coordinate

W1

823000.7E

834889.7N

W2.1, W2.2

(Before 6/7/04)

DP1-DP8

(After 6/7/04)

To follow actual discharge location on site.(1)

 

 

 

 

 

 

 

Note:     1) Monitoring will be conducted according to the monitoring schedule and water sample will be taken for analysis if water discharge from the construction site was observed at these locations.

Monitoring Methodology, Calibration Details and QA/QC Procedures

Operating/Analytical Procedures

4.5              The details of operating/analytical procedures for water quality monitoring are described in the previous EM&A Monthly reports.

Maintenance and Calibration

4.6              The details of requirements of maintenance/calibration are described in the previous EM&A Monthly reports.

 

Results and Observations

4.7              Water quality monitoring was conducted as scheduled in the reporting month. The DO concentration (3.8 mg/L) at W1 measured on 15 August 06 did not comply with the Compliance Level but within the baseline level (2.2-9.4mg/L). In addition, no construction activity was undertaken adjacent to the monitoring location. The non-compliance of DO level is therefore considered not due to the project activity. No further action was required.

4.8              There was no water discharge from the construction site during the reporting month. As such, no water sample was taken at DP1 to DP8.

4.9              The monitoring data and graphical presentations of the monitoring results are shown in Appendix H.