Agreement No. CE 4/2009 (EP)
Environmental Monitoring and Audit
for Contaminated Mud Pit at Sha Chau
(2009-2013) - Investigation
19th MONTHLY
PROGRESS REPORT FOR CONTAMINATED MUD PITS AT SHA CHAU - January 2011
1.1
Background
Since 1992, the East of Sha Chau area has been the site of a series of dredged
contaminated mud pits (CMPs) designed to provide
confined marine disposal capacity for contaminated mud arising from the HKSAR’s dredging and reclamation projects. CMP IVc is
presently in operation for backfilling by contaminated mud and is anticipated
to reach its capacity in 2011. A series
of four newly constructed seabed pits at the East of Sha
Chau area, CMP Va-d, will
be provided for the disposal of contaminated mud after CMP IVc
is full. Dredging operations were
completed for the construction of CMP Va and are now taking
place to construct CMP Vb. The
environmental monitoring and audit (EM&A) programme for the CMPs at the East of Sha Chau area presently covers disposal and capping operations
at CMP IV and dredging operations at CMP Vb.
1.2
Reporting
Period
This Monthly Progress Report
covers the monitoring period of January 2011.
1.3
Details
of Sampling and Laboratory Testing Activities
The following monitoring activities have been undertaken for CMP IVc and CMP Vb in January 2011:
·
Impact Water Quality Monitoring during Dredging Operations for CMP V was conducted on 4
January;
·
Water Column
Profiling for CMP IVc was conducted on 6 January; and
·
Demersal Trawling for CMP IVc
was conducted on 13-14 January.
A summary of field activities are
presented in Annex A.
1.4
Details
of Outstanding Sampling and / or Analysis
No outstanding sampling and laboratory analysis remained from January
2011.
1.5
Brief
Discussion of the Monitoring Results
Results of Impact Water Quality Monitoring
during Dredging Operations for January 2011 are presented for CMP V. Detailed results will be discussed in the
relevant Quarterly Reports.
1.5.1
CMP V
Impact Water Quality Monitoring
during Dredging Operations of CMP V – January 2011
Impact
Water Quality Monitoring during Dredging Operations of CMP V was conducted on
4 January 2011. On the survey day, sampling was
conducted during both mid-ebb and mid-flood tides at two Reference (Upstream) stations
upstream and five Impact (Downstream) stations downstream of the dredging
operations at CMP V. Monitoring was also
conducted at the Ma Wan station. At each
station, in-situ measurements of
water quality parameters as well as water samples were taken from three depths
in the water column (ie surface: 1 m below sea
surface, mid-depth and bottom: 1 m above the seabed).
Monitoring results are
presented in Table B1 of Annex B. Levels
of Dissolved Oxygen (DO), Turbidity and Total Suspended Solids (TSS) generally complied
with the Action and Limit Levels set in the Baseline
Monitoring Report ([1]). Levels of
TSS and Turbidity exceeded the Action Level in the downstream station DS1
during the mid-ebb tide. Station DS1 is
located on the edge of the works area of CMP Vb and
the compliance of Action and Limit Levels at other downstream stations (ie DS2-4) outside the works area would indicate that there
is no evidence of any unacceptable adverse water quality impacts arising from
the dredging operations of CMP V at ESC.
1.6
Activities
Scheduled for the Next Month
Water Column Profiling, Water Quality Monitoring during Capping and Demersal Trawling will be undertaken for CMP IV while Impact Water Quality Monitoring during Dredging will be undertaken
for CMP V in the next monitoring month.
The sampling schedule is presented in Annex A.
1.7
Study
Programme
A summary of the Study programme is presented in Annex C.