METHOD STATEMENTS FOR DREDGING WORKS
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (9.32 MB, 113 trang )
Comment Response Sheet (CRS)
Project Title
Van Phong 1 BOT Thermal Power Plant Project
Document Title
METHOD STATEMENTS FOR DREDGING WORKS
Document Type
For Approval
Document No
VP1-0-L4-C-GEN-10019
Returned Status
AC
Prepared by
CRS No
VP1-0-L4-C-GEN-10019-D-CRS
CRS Issued Date
08-Jun-2020
Engineer
Construction
Review
Date
Status O/C *
Remarks
27-03-2020
Open
08-05-2020
Closed
21-05-2020
Closed
No.
Section/
Page
1
Page 1
Owner’s Comment
General comment:
(i) Please clarify elevation system is NDL or CDL where
mention elevation number
(ii) All dredging equipment have to install Automatic
Identification System (AIS) and video camera according
to Decree 159/2018 ND-CP.
08-05-2020
Noted
Lot-4 please submit documents related to AIS
before start working.
Response to Comment
L4
(i) Elevation system is NDL
(ii) DHI will be applied for hopper barge and THSD
only, all Clamshell and Flat Barge did not applied.
19-05-2020
Noted
21-05-2020
Closed
Page 1 of 14
Comment Response Sheet (CRS)
2
Page 2
(1) Please make clear whether all dredged materials
are suitable for use in reclamation and how about the
unsuitable materials?
(2) The temporary tide gauges shall be installed to give
immediate visual measurements of sea level. Please
describe more detail.
(3) How can Contractor to ensure there are no localized
high spots of the dredged areas before acceptance of
the final levels by the Owner. Please describe more.
(1) Based on EIA report which has been approved by
government, all dredged material can be reuse for
landfill.
08-05-2020
(1)&(2): Agreed
(3) Multi-beam echo sounder is not clear. Please
reflect in the ITP also.
19-05-2020
(3) ITP has been issued according to multi-beam eco
sounder method, multi-beam eco sounder is common
method to ensure that these are no localized high
spots of the dredged areas
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
(2) DHI has revised on MS (section 2.1.2)
(3) For Post survey and Final survey, the Contractor
shall do the survey with 10m interval lines and multibeam echo sounder to obstruction detecting
21-05-2020
Noted
3
Page 3
Please point out where are construction buoys and
specification of them?
DHI has revised on MS (section 2.1.1)
08-05-2020
Open: please describe construction buoys which
will issued maritime notice by Port Authority as
well.
19-05-2020
Navigation buoys is requested to marine notice
by Port Authority that described on the Marine
Safety Assurance Plan
21-05-2020
Closed
4
Page 3
Please clarify design and slope protection of this area.
08-05-2020
Closed
Slope is mention on drawing deign which will be
submitted separately document
Page 2 of 14
Comment Response Sheet (CRS)
5
Page 4
Please consider Vietnam has a series of international
conventions governing maritime safety agreement, it
should be referred on this MS
08-05-2020
There is not any convention added such as
MarPOL 73/78 for oil prevention, SOLAS-74 for
safety of life at sea, STCW convention for training
certification and watching for seafarers, etc.
6
Page 4
DHI has revised on MS (section 1.3.3)
19-05-2020
DHI has revised on MS (section 1.3.3
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
21-05-2020
Closed
"Described"
DHI has revised on MS (section 1.4)
08-05-2020
Closed
7
Page 4
EL (NDL)?
Elevation system is NDL
08-05-2020
8
Page 4
Closed
4,0mCD according to design drawing.
DHI has revised on MS (section 1.4)
08-05-2020
Closed
9
Page 4
How many m3 per hour?
DHI has revised on MS (section 1.5)
08-05-2020
Closed
10
Page 5
How many m3 per hour?
DHI has revised on MS (section 1.5)
08-05-2020
Closed
11
Page 5
How many m3 per hour?
08-05-2020
DHI has revised on MS (section 1.5)
Closed
Page 3 of 14
Comment Response Sheet (CRS)
12
Page 5
(i) Please add the recuse boat, passenger boat and tug
boat (if any) to the list
(ii) All marine equipments have to be obtained permit
from Port Authority before work in the Project.
(i) DHI has revised on MS (section 1.5)
(ii) All marine equipment’s will be obtained permit from
Port Authority before work in the Project
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
08-05-2020
13
Page 6
Closed
Please describe, here, this is subcontractor EHS
manager right? where is EHS supervisor???
DHI has revised on MS (section 1.6)
08-05-2020
14
Page 7
Closed
- Supplement the circle duration of each equipment.
- Supplement the estimated capacity of each equipment
per day, required q'ty per day and number of equip. to
be assigned at each location to assure schedule.
DHI has revised on MS (section 2.2 and 2.3)
08-05-2020
15
Page 8
Closed
(i) Please clarify where is tide gauge station? The tide
gauge have to comply with Article 9.2.6.2 in
specification.
(ii) Please describe frequency, line interval of postsurvey
(iii) Final survey should be mentioned as well.
08-05-2020
16
Page 9
Closed
Font
(i) DHI has mention on section 2.1.2, location will be
confirmed later
(ii) DHI has revised on MS (section 2.2.4) and it will be
complied with ITP which will submit separate
document.
(iii) DHI has revised on MS (section 2.2.5) and it will be
complied with ITP which will submit separate
document.
DHI has revised MS
08-05-2020
Closed
17
Page 9
This sentence is not clear, please explain
08-05-2020
DHI has corrected and deleted it, it’s not applied.
Closed
Page 4 of 14
Comment Response Sheet (CRS)
18
Page 11
Please explain how the trucks can run on landfill without
getting bogged down?
08-05-2020
Noted
Lot-4 please pay more attention on safety matter
during construction stage.
The truck is transporting dredged material to the
Landfill and dumping, method is same with site
development method which was approved by Owner
27-03-2020
Open
08-05-2020
08-05-2020
Closed
21-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
DHI noted
21-05-2020
19
Page 12
Closed
the depth is lower than -6.0m, it means EL. <= -6.0m?
Please correct it.
Yes, it means EL <=-6.0M
08-05-2020
20
Page 12
Closed
English please
DHI has revised MS (section 2.2.1)
08-05-2020
Closed
21
Page 13
English please
DHI has revised MS (section 2.2.1)
08-05-2020
Closed
22
Page 14
This figure is not clear.
DHI has revised MS (section 2.2.1)
08-05-2020
Closed
23
24
Page 14
Page 15
Can Cutter Suction Dredger make the slope ( 1: 4 ) ?
Please state how the slope
is constructed.
08-05-2020
Closed
Please provide silt protector in this drawing.
08-05-2020
DHI will use Clamshell to make the slope
DHI has revised MS (section 2.2.1)
Closed
Page 5 of 14
Comment Response Sheet (CRS)
25
Page 15
Where is it? Please provide detail design drawing of
temporary jetty.
DHI has revised MS (section 2.1.4)
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
27-03-2020
Open
08-05-2020
Closed
08-05-2020
26
27
Page 15
Page 16
Closed
When Intake canal is dredged by Clamshell, Silt Curtain
may be needed to prevent diffusion of dredged material.
Please state how the slope (1: 1.5) is constructed.
08-05-2020
Closed
Any fall free prevention here?
08-05-2020
OPEN
Please reflect it in this document for site implementation
21-05-2020
OPEN.
There is no reflection at the section 2.1.4
DHI will prepare the silt-protector frame standby for
diffusion of dredged material, any slope will be done
by clamshell.
DHI will install the Curb to prevention fall free
19-05-2020
DHI has revised on MS rev C(section 2.1.4)
26-05-2020
DHI has revised on MS rev D(section 2.1.5)
08-06-2020
Closed
28
Page 19
It is recommended to classify the oil spills based on real
site condition, and detail the resources against oil spill
in response to article 6 and article 8 of decision No
02/2013/QD-TTg which did not mention in the "Plan of
Safety Marine assurance" document and "Oil spill
prevention plan".
DHI has explain in meeting with Owner/consultant,
Please see more detail on attachment 03:
Countermeasure to prevent oil leaks during dredging
08-05-2020
Closed
Page 6 of 14
Comment Response Sheet (CRS)
29
Page 19
There is no information for "Dredging plan including
mitigation measure and monitoring", no information of
"Waterway Traffic Safety Management Plan for
Dredging Activity", no information of as EPC's
commitment in the "EPC plan for detail HSE
documents"
Mitigation measure and monitoring has mention on MS
(section 4.4.1)
Other document will be submitted separately by DHI’s
EHS department.
27-03-2020
Open
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
08-05-2020
OPEN
It is recommended to submit pertaining to this
document.
19-05-2020
Noted, but the MS cannot mention all document in
case
21-05-2020
OPEN
L4 has committed in the "EPC plan for detail HSE
documents" that These contents will be included
Method Statement for Dredging work plan.
26-05-2020
Mitigation measure and monitoring has mention on MS
(section 4.4.1), please refer to attachment 05 for water
way traffic safety management.
08-06-2020
30
Page 19
Closed
Is this sufficient?????
DHI has revised on MS (section 4)
08-05-2020
Closed
31
Page 19
Lifeboat will be inspected base on which code &
standard? Please describe detail
08-05-2020
OPEN
There is nothing revised
21-05-2020
OPEN
There is not any information, specification for
rescue boat at the attachment #3
08-06-2020
DHI has corrected its name and revised on MS
(section 4.1.3)
19-05-2020
Rescue boat is replaced for life boat in case,
recuse boat is mention on attachment #3
26-05-2020
Life boat will not use in this project, Passenger
boat is arranging to rescue in this time but DHI will
mobilize addition Speed boat prior Coal jetty piling
work start.
Closed
Page 7 of 14
Comment Response Sheet (CRS)
32
Page 20
How long will be placed ring buoy
Ring buoy will placed with 5-10m
08-05-2020
OPEN
Please reflect it in this document
19-05-2020
DHI has revised on MS rev C(section 4.2.3)
21-05-2020
33
Page 20
Closed
Please describe standard rescue boat
08-05-2020
OPEN
Please refer to attachment 04 for detail comment
21-05-2020
OPEN
Please clarify the standard, specification for the rescue
boat. There was no confirm from Owner management
team for L4's proposal in the meeting.
DHI has explain in meeting with Owner/consultant,
Please see more detail on attachment 03 :
EMERGENCY RESCUE BOAT PLAN
19-05-2020
DHI has provide on attachment #03
26-05-2020
Please see attachment o6 for this comment.
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
08-06-2020
34
Page 21
Closed
Please describe all scenario of emergency response
here
DHI has revised on MS (section 4.1.8.2)
08-05-2020
35
Page 21
Closed
Who is report incident/accident to EHS officer?
DHI has revised on MS (section 4.1.8.2)
08-05-2020
Closed
36
Page 23
What the standard, please list out, project requirement
should be addressed
DHI will comply with document Health, Safety and
Environment Plan (VP1-0-EPC-H-GEN-10511) which
has been submitted separately to Owner/Consultant
08-05-2020
OPEN
Please reflect it in this document for site implementation
21-05-2020
19-05-2020
Noted but MS could not mention all document incase,
any relation document will be shared to parties for site
implement
Closed
Page 8 of 14
Comment Response Sheet (CRS)
37
Page 23
What is necessary PPE?
DHI has revised on MS (section 4.2.2)
08-05-2020
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
27-03-2020
Open
08-05-2020
Closed
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
Closed
38
Page 26
Please determined where is mooring area in case of
bad weather abnormal weather and describe more
detail on this ms
DHI has revised on MS (section 4.3.2)
08-05-2020
39
Page 27
Closed
What is countermeasure to minimized diesel spill
response prevention?
DHI has mention on attachment 02:
COUNTERMEASURE TO PREVENT OIL LEAKS
DURING DREDGING
08-05-2020
40
Page 27
Closed
Which training course will be delivered?
DHI will train/guider worker how to classify waste
material and put it in the right place
08-05-2020
OPEN
Please reflect it detailed in this document for site
implementation
19-05-2020
Noted, this scope will be guide to worker in general
safety induction course what is held for new worker
21-05-2020
41
Page 27
Closed
It is sea, not river
DHI has been revised on MS
08-05-2020
Closed
42
Page 27
According to EIA, suspended solids near the dredging
area or surrounding fixed points will be monitored
during the dredging process. Please detail describe this
activity.
This activity will be done by third party(EIA) and detail
plan will be submit in separately document
08-05-2020
Noted. But name of third party is EIA. Is that correct?
Detail of monitoring plan has to be get approved before
start dredging work.
19-05-2020
Noted, name of third party correctly is IE
21-05-2020
Closed
Page 9 of 14
Comment Response Sheet (CRS)
43
Page 1 of 2
It seem no review from Doosan's HSE team on this
document. the content of this risk assessment is too
meager and not comply with risk assessment
procedure. it is requested to revise.
All safety activity will be under review by DHI’s EHS
team, and DHI has been revised risk assessment on
attachment 04
08-05-2020
OPEN
As confirmed from DHI that Doosan's HSE team has
revised the risk assessment why the risk assessment
on attachment 02 is not in line with Doosan's risk
assessment procedure? Please check and revise
accordingly.
19-05-2020
Noted
27-03-2020
Open
08-05-2020
Open
21-05-2020
Closed
08-05-2020
Open
21-05-2020
Closed
08-05-2020
Open
21-05-2020
Closed
08-05-2020
Open
21-05-2020
Closed
08-05-2020
Open
21-05-2020
Closed
21-05-2020
44
Page 10
Closed
08-05-2020
Warning light is recommended to install on top of
buoys and anchor buoys for night time observation.
19-05-2020
This is marking buoy for dredge area only, it will not
make damage/affect with others thing(if any), warning
light available on each dredge equipment
21-05-2020
Closed
45
Page 10
08-05-2020
Please point out construction buoys which shall be
issued maritime notice by Port Authority?
19-05-2020
DHI has revised on MS rev C (section 2.1.1)
21-05-2020
46
Page 16
Closed
08-05-2020
Lot-4 please ensure that has no obstruction between
both jetty during construction stage.
19-05-2020
Noted, DHI is ensure that it has no obstruction
between both jetty during construction stage.
21-05-2020
47
Page 17
Closed
08-05-2020
Anchor buoy with warning light is recommended
21-05-2020
19-05-2020
DHI is noted
Closed
Page 10 of 14
Comment Response Sheet (CRS)
48
Page 21
08-05-2020
Regarding silt curtain: Lot-4 please provide specification
of silt curtain, such as open size of silt curtain, grab
frame type, etc...to ensure silt curtain can minimize
turbidity spread out surrounding sea area.
19-05-2020
DHI has revised on MS rev C(section 2.2.1)
08-05-2020
Open
21-05-2020
Closed
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
21-05-2020
49
Page 27
Closed
08-05-2020
General comments: Please note that AIS track records
and video record is part of inspection record data. It is
required to submit frequency.
21-05-2020
OPEN
Please find further comment on page 29 of 46.
50
Attachment 4
Page 1
08-06-2020
Noted.
(i) Owner/consultant will do inspection of AIS and Video
recorder installation before put it on operation.
(ii) AIS account have to share to Owner/Consultant to
supervise purpose.
08-05-2020
Please clarify what is the specification for the rescue
boat? are there any reference for owner's information?
21-05-2020
OPEN
There is not any specification for rescue boat in the
attachment 03.
19-05-2020
Noted, DHI will submit to Owner as soon as possible
26-05-2020
AIS track records and video record is installed on
hopper barge and on tug boat which will pulling flat
barge
10-06-2020
Noted
Closed
19-05-2020
Please see attachment for clarify (attachment 03)
19-05-2020
Please see attachment to clarify this
comment(attachment 06)
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
08-06-2020
Closed
Page 11 of 14
Comment Response Sheet (CRS)
51
Attachment 4
Page 1
08-05-2020
1. How to rescue the victim in some case where the tug
boat can not be approached due to the sunken bottom
the tug boat is too deep.
2. How to move the victim who has broken bones from
the see to tug boat when it is too height from the
surface of water lever.
3. In the emergency case the time is limited, so it is not
sufficient for tug boat operation, moreover, the tug boat
shall be operated with high speed in the emergency
case and there contain many blind area, big wave.
4. With above three analysis. It is recommended to use
the professional rescue boat which mentioned in
SOLAS Convention which Vietnam is a member or any
other reasonable specification suggested by EPC
contractor for VPCL's review
21-05-2020
OPEN
Please refer to attachment 3 for detail comment.
19-05-2020
DHI has changed the rescue boat (attachment 03)
Occupied the hard type bed and other facilities as
below,
08-05-2020
Open
21-05-2020
Open
08-06-2020
Closed
21-05-2020
Open
08-06-2020
Closed
26-05-2020
Offshore Rescue Drill has been conducted one time to
exercise rescue if any accident/incident happen, this
activity will be held on 2~3 month one time. Passenger
boat is arranging to rescue in this time but DHI will
mobilize addition Speed boat prior Coal jetty piling
work start.
08-06-2020
52
5
Closed
21-05-2020
Please revise the volume according to DONRE
consent.
26-05-2020
DHI has revised on MS rev D (section 1.4)
08-06-2020
Closed
Page 12 of 14
Comment Response Sheet (CRS)
53
24
21-05-2020
This route is not in line with approved maritime safety
assurance plan.
26-05-2020
DHI has confirmed with PA NT that We can update/
supplement again when MS approval.
08-06-2020
10-06-2020
DHI has deleted this route on Ms rev E
OPEN. Not only Maritime Safety Assurance Plan, but
EIA also should be updated new route and get
approval, otherwise the route will be not approved by
Owner.
54
29
21-05-2020
According to Decree No. 159-ND/CP-2018, all
equipment’s which transport dredged material have to
install AIS and video recorder.
21-05-2020
Open
08-06-2020
Open
Closed
26-05-2020
AIS track records and video record is installed on
hopper barge and on tug boat which will pulling flat
barge
21-05-2020
Open
08-06-2020
Closed
26-05-2020
21-05-2020
Open
Offshore Rescue Drill has been conducted one time to
exercise rescue if any accident/incident happen, this
activity will be held on 2~3 month one time. Passenger
boat is arranging to rescue in this time but DHI will
mobilize addition Speed boat prior Coal jetty piling
work start.
08-06-2020
Closed
08-06-2020
Closed
55
Emergency
Rescue Boat
Page 1
21-05-2020
1. How to rescue the victim in some case where the
boat DU LICH 36 can not be approached due to the
sunken bottom the tug boat is too deep.
2. How to move the victim who has broken bones from
the see to boat DU LICH 36 when it is too height from
the surface of water lever.
3. In the emergency case the time is limited, so it is not
sufficient for boat DU LICH 36 operation, moreover, the
tug boat shall be operated with high speed in the
emergency case and there contain many blind area, big
wave.
4. With above three analysis. It is recommended to use
the professional rescue boat which mentioned in
SOLAS Convention which Vietnam is a member or any
other reasonable specification suggested
08-06-2020
Closed
Page 13 of 14
Comment Response Sheet (CRS)
58
59
11
25
08-06-2020
Assessment negative impact to environment in
this revision compared with previous revision to be
compared with approved one before execution.
08-06-2020
Assessment negative impact to environment in
this revison compared with previous revision to be
compared with approved one before execution.
10-06-2020
Noted, from Ms rev A, DHI has mention that
when tide down and at shallow area excavate
method by excavator is conducted directly, this
step is dispatched to more improvement any
negative impact to environment.
10-06-2020
DHI has deleted this route on Ms rev E
08-06-2020
Open
Noted
08-06-2020
Open
Noted
Additional Notes (if any)
* O - Open, C – Closed
Page 14 of 14
AP
APPROVED
Approved
AC
APPROVED WITH COMMENT
Contractor to revise the correction and resubmit
NOT APPROVED
For Approval
NA
Revise the correction and resubmit before proceeding
RE
REVIEWED
Information acknowledged with no comment
RC
REVIEWED WITH COMMENT
Information acknowledged with comments
Note: Approval or comment does not relieve the Contractor of
all obligations covered under contract
E
10-Jun-2020
D
For Approval
KS KIM
ET KIM
27-May-2020
JH CHOI
Discipline: Civil
18 Jun
20
For Approval Date:
JH CHOI
KS KIM
ET KIM
C
19-May-2020
For Approval
JH CHOI
KS KIM
DS YU
B
25-Apr-2020
For Approval
JH CHOI
KS KIM
DS YU
A
13-Mar-2020
For Approval
JH CHOI
KS KIM
ET KIM
REV
DATE
DESCRIPTION
Approved
Checked
Prepared
OWNER
VAN PHONG POWER COMPANY LIMITED
PROJECT
Van Phong 1 BOT Thermal Power Plant Project
Status
□Approved
□Approved with Comment
□Not Approved
□Reviewed
OWNER’S ENGINEER
Pöyry Switzerland Ltd.
EPC CONTRACTORS
IHI–TESSC–CTCI–DHI CONSORTIUM
PROJECT DOCUMENT No
REV
VP1-0-L4-C-GEN-10019
E
DOCUMENT TITLE
METHOD STATEMENTS FOR DREDGING WORKS
EPC
EPC DOCUMENT No.
VP1-0-L4-C-GEN-10019
Doosan Heavy Industries and Construction
REV
E
Page | 1
METHOD STATEMENTS FOR DREDGING WORKS
TABLE OF CONTENTS
1
1.2
1.3
1.3.2
1.3.3
1.4
1.5
1.6
1.7
1.8
2
2.1
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
2.1.6
2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.3
2.3.1
2.3.2
3
3.1
3.2
3.3
3.4
4
4.1
4.1.1
4.1.2
4.1.3
4.1.4
4.1.5
4.1.6
4.1.7
4.1.8
4.2
4.2.1
4.2.2
4.2.3
4.3
4.3.1
GENERAL .............................................................................................................. 4
Purpose .................................................................................................................... 4
Reference documents .............................................................................................. 4
Technical Documents .............................................................................................. 4
Codes and Standards .............................................................................................. 5
Scope of work .......................................................................................................... 5
The equipment mobilization plan: .......................................................................... 5
Site Organization Chart .......................................................................................... 7
Sequence of work .................................................................................................... 8
General schedule ..................................................................................................... 8
METHOD OF CONSTRUCTION WORKS .......................................................... 9
Site preparatory work ............................................................................................. 9
Setting of construction buoy ................................................................................... 9
Onshore excavation and dredging work ............................................................... 10
Tide gauge installation .......................................................................................... 10
Pre-dredging Survey ............................................................................................. 11
Landfill Area & Temporary Jetty......................................................................... 13
Anchors and moorings .......................................................................................... 18
Work method ........................................................................................................ 18
Dredging area planning......................................................................................... 18
Depth dredging control: ........................................................................................ 24
Interim dredging survey ....................................................................................... 25
Post-dredging survey ............................................................................................. 25
Final survey ........................................................................................................... 25
Dredging productivity ........................................................................................... 25
Productivity of Clamshell...................................................................................... 25
Productivity of TSHD ........................................................................................... 26
MANAGEMENT OF WORK ............................................................................ 28
Dredging tolerance .............................................................................................. 28
Site Coordinates and Elevation Control ............................................................ 28
AIS system (applied for hopper barge disposal only)....................................... 28
Inspection and Test Plan ..................................................................................... 29
HEALTH, SAFETY AND ENVIRONMENT ORGANIZATION ....................... 30
General Safety Procedures ................................................................................. 30
Floating Plant & Equipment .............................................................................. 30
Marine Safety Assurance Plan ........................................................................... 30
Inspection of safety equipment ........................................................................... 30
Marine Works ...................................................................................................... 30
Work Over Water................................................................................................ 31
Housekeeping ....................................................................................................... 31
Fire Precautions ................................................................................................... 32
Site Situation Response and Emergency Response........................................... 32
Safety Practice Rules ........................................................................................... 34
Marine work......................................................................................................... 34
Personal Protection equipment (PPE) ............................................................... 34
Risk Assessments ................................................................................................. 36
Maritime Safety Assurance................................................................................. 38
Maritime Safety Assurance................................................................................. 38
P a g e |2
METHOD STATEMENTS FOR DREDGING WORKS
Gathering of construction equipment when suspended ................................... 38
Plan for coordinated implementation ................................................................ 39
Studying, training, inspection and supervision of traffic safety ...................... 40
Environmental considerations ............................................................................ 40
Mitigation measures ............................................................................................ 40
5
ATTACHMENT ................................................................................................... 42
ATTACHMENT 01: SCHEDULE FOR DREDGING WORKS ......................................................... 43
ATTACHMENT 02: COUNTERMEASURE TO PREVENT OIL LEAKS DURING DREDGING . 44
ATTACHMENT 03: EMERGENCY RESCUE BOAT PLAN ............................................................ 45
ATTACHMENT 04: RISK ASSESSMENT ......................................................................................... 46
ATTACHMENT 05: Transportation and Traffic Mitigation .............................................................. 47
ATTACHMENT 06: LSA Rescue Boat Requirement .......................................................................... 48
4.3.2
4.3.3
4.3.4
4.4
4.4.1
P a g e |3
METHOD STATEMENTS FOR DREDGING WORKS
1
GENERAL
1.2
Purpose
The Van Phong 1 BOT Thermal Power Plant is located in Van Phong bay and contiguous to
My Giang transshipment and petrol intrepot warehouse area.
The purpose of this Method Statement is to describe the methodology involved in dredging
works at the approved area in accordance with the technical standard and EHS requirements
of Van Phong 1 BOT Thermal Power Plant Project.
DREDGING AREA 2
Discharge Canal
(EL-4.1m)
LANDFILL
Disposal Area
DREDGING AREA 3
Unloading Ramp
(EL-5.6m)
DREDGING AREA 1
Coal Jetty Front
(EL-18.3m)
DREDGING AREA 4
Intake Canal
(EL-5.1m)
Figure 1. General plan of Dredging works
1.3
Reference documents
1.3.2
Technical Documents
Drawing:
-
VP1-0-L4-C-GEN-00101 to 00109
Documents:
-
VP1-0-L4-C-GEN-00001_Soil Investigation Report (Rev.C);
Part III-2 Exhibit B1 Tech Spec Section 9;
P a g e |4
METHOD STATEMENTS FOR DREDGING WORKS
1.3.3
1.4
Report on changed items from immersion at sea to landfill by dredged material for Van
Phong 1 BOT Thermal Power Plant project.
Codes and Standards
-
TCVN 4055-85
Construction Plan;
-
TCVN 2287 1978
Construction Safety Standard System. Basic Regular
-
TCVN 4447-2012
Earth works. Rules for the construction and acceptance
-
Decision 24/QD-KT4 Process of working acceptance of dredging work for waterway
transportation by mechanical means.
-
TCVN 9401-2012
Technical Standard of GPS Survey and Processing for
Construction geodetic
-
Decree 46/2015/NĐ-CP: Quality Control and Maintenance of Project Construction
-
TCVN 5674-1992
-
Vietnam Maritime Code dated 2015
-
Decree No. 58/2017/NĐ-CP dated 10 May, 2017 of the Government regulating in
details some Article of Vietnam Maritime Code about marine operation management;
-
Decree 159/2018/NĐ-CP: Management of Dredging Activities in The Water Areas of
Seaports And Inland Waterways
-
International Convention for the Safety of Life at Sea (SOLAS),1974- LSA – Code
International Life – Saving appliance Code (MSC.48(66))
-
International Convention for the Prevention of Pollution from Ships (MARPOL 73/78)
(Appendix I, IV, V)
Scope of work
Finishing work for Project Construction.
This method statement described the work sequence, manpower and equipment for dredging work
in coal jetty, unloading ramp front area, and intake and discharge canal area.
The dredging works will be carried out by designed suitable equipment and disposal will be
dump on the Landfill.
The Contractor will carry out the following dredging work with it estimated volume
No.
1
2
3
4
5
1.5
Table 1. Dredging works summary
Dredging work
Bottom
Volume
Elevation
(Estimation)
(NDL)
Coal Jetty Front Area
EL.-18.3m
141,369
Unloading ramp front Area
EL.-5.6m
139,346
Intake Canal
EL.-5.1m
29,807
Discharge Canal
EL.-4.0m
105,051
Landfill
415,573 m2
The equipment mobilization plan:
Table 2. Equipment mobilization for Dredging
P a g e |5
METHOD STATEMENTS FOR DREDGING WORKS
No.
1
Equipment name
Trailing Suction Hopper Dredger
Capacity
Quantity
4500 HP -
1
Remarks
Hopper 1500m3
2
Floating pump station equipped 02
pump machines
3
2 x 400 HP
1
3
320m /h
Bucket 6-8m3
Clamshell
4
216m3/h
4
Transportation Barge
600-1000m3
6
5
Tug boat
450HP
2
6
Unloading excavator
Bucket 1.2-1.4m3
4
7
Truck
15m3
04
8
Land excavator
Bucket 1,2m3
02
9
Bull-dozer
D300
01
10
Emergency boat
20 HP
01
11
Rescue boat (by Tugboat)
Note: Certificates and insurances for the above equipment shall be separately submitted to the
Employer before mobilization to the Site. And All marine equipment shall be obtained permit from
Port Authority before work in the Project
Table 3. Plan of Equipment mobilization for Dredging
S/N
2020
Descriptions
Duration
1.1
Dredging work
1.1.1
CW Unloading ramp
5M
1.1.2
CW intake & discharge canal
4M
1.1.3
Coal unloading jetty
3M
2.1
Landfilling work
2.1.1
Preparation & maintenance of landfill area
2.1.2
Leveling and compaction on landfill area
S/N
1
Description
Trailing Suction Hopper Dredger
3
Floating pump station equipped 02 pump
machines, D200 pump pipe
Clamshell
4
Material Transportation Barge
2
Capacity
3
4
5
6
7
8 9
10
11
12
Equipment
-Month
4500HP
1,500 m3
3
1
1
1
2x400HP
3
1
1
1
60 Tons
18
2
4
4
4
4 2
600-1000m3
28
2
6
6
6
6 2
P a g e |6
METHOD STATEMENTS FOR DREDGING WORKS
S/N
2020
Descriptions
Duration
5
Tug boat
6
Unloading excavator
7
Truck
8
Land excavator
9
Bull Dozer
10
450HP
3
10
4
1.2-1.4m3
6
7
8 9
2
2
2
2 1
4
4
4
4
4
4
4 2
1
1
1 1
1
1
1 1
15 m3
20
2
4
Bucket 1.2m3
9
2
2
D300
9
1
Rescue boat
1.6
5
1
1
10
11
1
12
1
Site Organization Chart
DHI
OFFSHORE TEAM
SUBCONTRACTOR
OF DHI
OEC
Site Manager
EHS MANAGER
QA/QC MANAGER
CONTROL ENGINEER
SURVEY & QUANTITY SURVEY TEAM
MECHANICAL ENGINEER
EHS SUPERVISOR
DREDGE TEAM
CONSTRUCTION
SUPERVISOR
DISPOSAL & LANDFILL TEAM
Figure 2. Site Organization Chart
P a g e |7
METHOD STATEMENTS FOR DREDGING WORKS
1.7
Sequence of work
Preparation work & Pre-survey
Setting out of dredging areas; disposal area
(LANDFILL), temporary jetty, floating pump
station and dredged material transport routes…
Moving equipment to dredging areas
Daily Dredging
Transport to Floating Pump Station
NOT
OK
Interim survey
OK
Final survey and Inspection
Demobilization
Figure 3. Dredging Sequence
1.8
General schedule
Please see ATTACHMENT 01: SCHEDULE FOR DREDGING WORKS
P a g e |8
METHOD STATEMENTS FOR DREDGING WORKS
2
METHOD OF CONSTRUCTION WORKS
2.1
Site preparatory work
2.1.1
Setting of construction buoy
The dredging areas shall be set out before commencement of work. Each dredging area shall
be located on site layout by construction buoys (marking buoys). For the navigation buoys, it
is installed as showed on the Marine Safety Assurance Plan.
Figure 4. Navigation buoys system
Figure 5: Marking position buoys plan for dredging area
P a g e |9
METHOD STATEMENTS FOR DREDGING WORKS
2.1.2
Onshore excavation and dredging work
Between onshore excavation and dredging works will be set up a divide boundary and
temporary cofferdam is constructed prior commencement of excavation in order to keep
dry condition, this location is termination point and it will be carry out by on-shore
contractor, specific:
<Discharge canal>
<Intake canal>
<Temp. Unloading Ramp>
< Section of temporary cofferdam (by onshore)>
-
2.1.3
Tide gauge installation
In order to control the vertical of the work, the tide gauge shall be installed to comply with the
requirement.
-
The tide gauges shall be installed at strategic locations around the Site. The temporary tide
gauges shall be installed to give immediate visual measurements of sea level. They shall be
constructed vertically and firmly fixed on rigid supports at locations agreed and shall be leveled
and fixed to give tidal readings within an accuracy of ±20mm. Temporary tide gauges shall be
made of 50mm thick hardwood and shall be at least 150mm wide and established with 0.0m at
the Chart Datum. The gauges shall be painted on the marked faces with alternate 100mm stripes
P a g e | 10
METHOD STATEMENTS FOR DREDGING WORKS
in red and white and shall be marked and numbered in black at 0.5m intervals over the tidal
range. The painting applied shall consist of one primary coat, two undercoats and one finishing
coat. [Please refer to figure 6]
TEMPORARY TIDE GAUGE
Hardwood (50mm thick, 250mm wide)
SECTION A-A
250
50
Steel Pipe D250mm, L5.0 m
Steel Pipe D250mm, L2.0 m
Red paint
White paint
A
Hardwood (T50mm, W250mm), L5.0m
A
Figure 6: Temporary Tide gauge
2.1.4
Pre-dredging Survey
• Survey equipment shall be inspected with full calibration document.
Table 3. Table of Survey Equipment
Equipment name
Capacity
Unit
Quantity
200 KHz
set
01
DGPS 110
set
02
Garmin map Cs 60
Set
04
Survey Boat
30 HP
set
02
Total Station
± 5PPM
set
01
± 3MM/KM
set
01
Echo Sounder
DGPS
GPS
Auto Level
Remarks
•
Permanence of bench marks will be set up, it is frequency checked and clarified by certified
surveyor or third party and it will be submitted to owner/consultant for approval in separate
document.
•
The dredging area will be surveyed by using echo sounder method.
P a g e | 11
