Agreement No. CE 4/2009 (EP)
Environmental Monitoring and Audit
for Contaminated Mud Pit at Sha Chau
(2009-2013) - Investigation
26th MONTHLY PROGRESS REPORT FOR CONTAMINATED MUD PITS AT SHA
CHAU August 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-b and are
now taking place to construct CMP Vc. 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 Vc.
1.2
Reporting Period
This Monthly Progress Report
covers the monitoring period of August 2011.
1.3
Details of Sampling and
Laboratory Testing Activities
Field sampling activities conducted in this monthly period for CMP IV
are listed below:
· Routine Water Quality Monitoring was conducted on 5
August;
· Water Quality Monitoring during Capping was conducted on
11 August;
· Demersal Trawling was conducted on 11 and 12 August;
· Benthic Recolonisation
Monitoring was conducted on 18 August;
· Cumulative Impact Sediment Chemistry Monitoring and Sediment Toxicity Monitoring were
conducted on 23 August; and
· Pit Specific Sediment Chemistry Monitoring was conducted on
25 August.
For CMP V, sampling for Impact Water Quality Monitoring during
Dredging Operations was conducted on
9 August 2011. A summary of field activities are presented in Annex A.
A summary of monitoring data
submitted by the Contractor in this reporting month is presented in Table 1.1.
Table 1.1 Summary
of monitoring data submitted by the Contractor during the reporting month
|
Key
Task |
Monitoring
Component |
Results
Received from the Contractor |
|
CMP
IV |
|
|
|
Water Column Profiling |
Water Quality |
July 2011 sampling: 19 August 2011 |
|
CMP
V |
|
|
|
Impact Monitoring during
Dredging Operations |
Water Quality |
July 2011 sampling: 19 August 2011 |
1.4
Details of Outstanding Sampling
and / or Analysis
No outstanding sampling and laboratory analysis remained from August
2011. However,
monitoring data were not collected for Water
Column Profiling of CMP IVc since contaminated mud
disposal operations were not undertaken during the surveys on 5 and 11 August
2011.
1.5
Brief Discussion of the
Monitoring Results
Results of Impact Water Quality
Monitoring during Dredging Operations of CMP V are presented for August
2011. Detailed results will be discussed
in the 9th Quarterly Report.
1.5.1
CMP V
Impact Water Quality Monitoring during Dredging
Operations of CMP V – August 2011
Impact
Water Quality Monitoring during Dredging Operations of CMP V was conducted
on 9 August 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) complied
with the Action and Limit Levels set in the Baseline
Monitoring Report ([1]). Therefore,
there appears to be 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
Impact
Water Quality Monitoring during Dredging Operations will be undertaken for CMP V in September 2011. No monitoring activities are scheduled for
CMP IV in the next reporting month.
The sampling schedule is presented in Annex A.
1.7
Study Programme
A summary of the Study Programme is presented in Annex C.