Gea Report(alignment Revised)

CONTENTS Sl.No

TITLE

1.

Introduction

2.

PAGE NO 1

1.1Location of the Jetty

2

1.2 Elevation details of the jetty

2

1.3 Elevation details of the unloading piers

2

Wave climate 2.1 Wave characteristics off Cuddalore coast

3 3

2.1.1 Operating wave conditions

3

2.1.2 Wave rose from wave atlas, NIO-1990

4

2.2 Wave characteristics from Buoy data

5

2.3. Storms and Depression

7

3.

Littoral Drift

39

4.

Details of the jetty

39

5.

Realignment of the approach channel & turning circle

39

6.

Estimation

41

7.

Summary

43

8.

Requirements for DPR

44

References

45

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

REVISED REPORT FOR THE OFFSHORE JETTY LAYOUT ON AN OPEN SEA COAL HANDLING SYSTEM OFF CUDDALORE COAST 1. INTRODUCTION Cuddalore Power company limited is planning to construct an open sea marine terminal off Cuddalore coast to unload coal for 2 x660MW capacity thermal power plant to be located at Thiagavalli village in south Arcot Vallalar District about 15 km south of Cuddalore. The proposed site is located along east coast of India at longitude 79 045’45”E and Latitude 11037’30”N in Bay of Bengal and located on the Southern side of Uppanar river. The Client has requested IIT Madras to prepare a preliminary layout and estimate for the provision of offshore coal handling system for the thermal plant. The basic data related to the project, arrived based on the discussions with the clients and used for the study are 1.

Coal requirement for the 2 x 660 MW power plant 4.0 million tonnes/year.

2.

No of conveyor belts

2

3.

The capacity of the each conveyor belt

2000 tonnes/hour

4.

Annual unloading capacity of two belt conveyors (for 300 working days in a year,

20

working

hours

per

day

with

80%efficiency

(ie.,2 x 2000 x 300 x 20 x0.8) is 19.2 million tonnes. 5.

Size of the vessels

6.

Particulars of the vessel:

Maximum 65,000DWT

SIZE OF THE LENGTH

WIDTH

HEIGHT

FULLY

LADEN

VESSEL(DWT) (m) 65,000 229.0

(m) 32.2

(m) 17.5

DRAUGHT (m) 12.2

7.

No of unloaders proposed on each pier

=

2

8.

Capacity of each unloader

=

2000 tonnes/hour

9.

No of Operable days

=

300 days

10.

No. of berths

=

2.0

11.

By Assuming 2.5 days for unloading a 65000 DWT ship, total handling capacity = (65000 x 2 x 300 x 0.9)/2.5

Client: Cuddalore Power Company Ltd.

2

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

(Considering 10% for maintenance & breakdown)= 14 million tonnes/year 1.1 LOCATION OF THE JETTY The cost of the jetty will be the minimum if the location is selected such that the required water depth is available at a shorter distance from the shore (i.e., the length of the jetty is minimum). A detailed bathymetry survey will provide the information about the sea bed contours. The minimum draft requirement is based on the full laden draught and hence, estimated as 15m with an under keel clearance of 2.5m. The 15m contour lies at a distance of 4.5km from the shoreline and to avoid extending the proposed jetty for longer distances, which increases the project cost and maintenance cost, the offshore jetty is proposed to be at 10m contours with a capital dredging upto -15m. The navigation of the vessels to the jetty is by the assistance of two tugs and a pilot boat of suitable capacity. 1.2 ELEVATION DETAILS OF THE APPROACH JETTY The top level of the approach jetty should be at +7.0m above chart datum to avoid frequent wave slamming. The bottom of the belt conveyor should be kept at +10.0 m to avoid wave slamming during hostile condition on the belt conveyor. The bottom jetty level is to be kept at +5.8m to keep clean off high water line during normal operating conditions. The top level of the approach jetty need to be reviewed during detailed engineering. 1.3 ELEVATION DETAILS OF THE UNLOADING PIERS The top level of the unloading pier should be kept at +7.0m to facilitate effective berthing, mooring and unloading operation. The bottom of the belt conveyor should be at +10.0m to avoid the interaction of sea waves during extreme conditions.

Client: Cuddalore Power Company Ltd.

3

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

2.0 WAVE CLIMATE 2.1 WAVE CHARACTERISTICS OFF CUDDALORE COAST The wave characteristics play a vital role in the design and operation of the open sea marine terminal. It also governs the orientation of the unloading pier to obtain number of operable days in a year. The source for wave characteristics is the Wave Atlas for the Indian Coast published by NIO, Goa. This is based on the twenty years of ship observations. The coast off Cuddalore falls under grid no.4 of the wave Atlas. The data for wave atlas was collected during the voyages of ships in deeper water. Enough care should be given in the interpretation of these data (especially the wave direction). This is because of the fact that in deeper waters, the wave direction changes significantly. For example, during southwest monsoon (June to September), the predominant wave direction in the deeper waters of the Bay of Bengal is from south–west, whereas, the same near the coast is south-east. There is no detailed site specific wave data available for Cuddalore. However, the wave data off Chennai coast can be considered valid for Cuddalore coast, since the magnitude of the wave height, period and direction cannot vary significantly between Chennai and Cuddalore. 2.1.1. Operating wave conditions Based on the Indian Wave Atlas, 80% of the time in a year, the significant wave heights are upto 2.0m. The unloading operation can be carried out for 80% of the year, if 2.0 m significant wave height is considered permissible. The predominant wave period is from 812 seconds. During south- west monsoon, the waves approach the shore from south – east and during north – east monsoon, it approaches the shore from north-east. Mooring of the vessel in the head sea condition is preferable for smooth loading/ unloading operation, reduction of mooring forces and hence reduction in the cost of the unloading pier. Since almost 6 to 7 months in a year, the waves are from south-east, the unloading pier should be oriented towards south-east, at a bearing of 1350to the north. Hence the number of operable days for this pier configuration would be about 300 days in a year.

Client: Cuddalore Power Company Ltd.

4

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

2.1.2 WAVE ROSE FROM WAVE ATLAS, NIO-1990. The monthly rose diagram of wave heights for grid 4 for January to December is given in Fig. 2 to 13. The number inside the circle of the plot indicates the percentage frequency of calm condition. The rose diagram is given for every 10 0 interval. The notation for wave direction is that the waves are propagating towards the centre of the circles in these figures. The consolidated primary and secondary directions (first most predominant and second most predominant direction) for each month are given in Table 1. Waves of height upto 4.5m were observed. Ships generally avoid plying during hostile condition and hence waves of heights more than 4.5m is not reported by plying ships. Monthly rose diagram for wave periods from January to December is given in Fig 14 to 25. The primary wave directions and secondary directions are same as that for wave height. Wave periods from 5 to 14 seconds are commonly recorded and reported. TABLE 1. PRIMARY AND SECONDARY WAVE DIRECTION FOR EVERY MONTH OF A YEAR (NIO-1990) Primary wave

Secondary wave

SL.No

Month

direction(First

direction (Second

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

January February March April May June July August September October November December

Predominant) 600 600 900 1800 2100 2400 2400 2400 2100 1800 600 600

Predominant) 300 900 600 1500 1800 2100 2100 2100 2400 2100 300 300

Client: Cuddalore Power Company Ltd.

5

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

2.2 Wave characteristics from Buoy data The monthly wave characteristics are studied for the South West monsoon period i.e. May and October. The main characteristics, i.e. significant wave height, average period based on mo and m2 and the average wave direction for the period May and October 98 are presented below from the studies carried out from the NDBP buoy measurements. Significant wave height for May’98 (Fig. 26) is found to be varying from 0.5 to 1.5m with 1.3m wave having a maximum occurrence of 25%. About 80% of waves were having a maximum wave direction more or less uniformly distributed between 1100 and 1400. (Fig. 27). Average wave period (Fig. 28) is found to be between 3.5s and 6.5s with 4.5s as the most occurring wave period (43%). Wave periods are found to be varying from 3.5s to 8s, with 95% accounting for the periods between 4s and 8s for the month of October (Fig. 29). The maximum percentage occurrence of 34% is found to be at around 5.5s. High waves of 0.9m are found to be most occurring with a percentage of 45 and 0.7m and 1.1m waves accounted for another 43% (Fig. 30). There were occasional waves of 2.1m height also. The mean direction varied from 300 to 1600. The maximum percentage occurrence is 30% for the direction 125 0 (Fig. 31). Through out the year, the average wave period is found to be varying from 3s to 8s (Fig. 32) and the most occurring wave period for the year is 4s with 50% occurrence. The wave direction varies from 300 to 1600 having two peaks in the histogram corresponding to the directions 650 and 1250 (Fig. 33). Significant wave height (Fig. 34) shows a variation between 0.4m and 2.2m, even though the occurrence of 2m and higher waves are negligible. Sixty percentage of the waves are found to be having a significant wave height between 0.6m and 1.0m. From May to August, most of the waves are found to be having a direction between 1200 and 1400. From September to November, the direction is found to be shifting towards 650. The range of wave direction with significant percentage occurrence during this season is 600 to 1500. More waves were coming in the direction between 60o and 80o during Dec-Jan. The tables (2) to (4) give the statistical wave characteristic off Cuddalore coast based on the above limited data provided by NIOT [Neelamani, 1996].

Client: Cuddalore Power Company Ltd.

6

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Table2. Statistical Wave Characteristics Off Cuddalore. Range of wave

Av. Wave height

% of Occurences

% of cumulative

Height (m) 0.0 – 0.2 0.2 – 0.4 0.4 – 0.6 0.6 – 0.8 0.8 – 1.0 1.0 – 1.2 1.2 – 1.4 1.4 – 1.6 1.6 – 1.8 1.8 – 2.0 2.0 – 2.2 2.2 – 2.4 2.4 – 2.6 2.6 – 2.8 2.8 – 3.0 3.0 – 3.2

(m) 0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 2.7 2.9 3.1

8.67 12.33 13.67 9.00 12.00 8.00 7.00 8.33 8.30 3.37 5.33 2.00 1.00 0.30 0.00 0.37

Probability 8.67 21.00 34.67 43.67 55.67 63.67 70.67 79.00 87.30 90.67 96.00 98.00 99.00 99.30 99.30 99.67

Table3. Significant wave heights and corresponding significant wave periods for different return periods of occurrence. Return periods (yrs) 5 10 20 50 100

Significant wave Height (m) 4.30 4.60 4.95 5.45 5.80

Significant wave periods(s) 10.93 11.30 11.73 12.30 12.70

Table 4. Mean Wave Period in seconds. Month Jan Feb Mar Apr May Jun

Av. Period 7.18 6.97 7.61 10.15 10.31 10.32

Month Jul Aug Sep Oct Nov Dec

Av. Period 10.32 9.85 8.89 8.83 8.39 7.43

During storm period maximum storm wave height estimated is 9.36m and wave period as

Client: Cuddalore Power Company Ltd.

7

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

17.38 s. From the wave hind casting studies conducted by NIOT off the Cuddalore coast, design values of significant wave heights for return periods of 5, 10, 20, 50 and 100 years have been estimated as 4.3, 4.60, 4.95, 5.45 and 5.80m. The data on extreme height during cyclone is estimated as 9.36m. 2.3. Storms and Depression The project site forms part of the east coast wherein annually 18 depressions is formed in the Bay of Bengal out of which 6 turns out to be cyclonic storms on an average. Fig. 35 gives a statistics of the cyclones formed per year from 1945 – 2000 (including the depression). Regarding Cuddalore between 1891 and 1970, 3 storms crossed during the month of January, 2 storms in the month of March, 2 storms in April and 3 in May. Between September and December, during October 8 storms crossed Cuddalore, 19 in November and 6 in December. In the last one decade there was no major storm crossing the Cuddalore coast. The storms and depressions cause a high rise in wave height, which are likely to cause damage to the apparent structures in the onshore and offshore domain if not designed for such condition.

Client: Cuddalore Power Company Ltd.

8

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.1. Grid Atlas. Location map indicating Grid 4.

Fig.2 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF JANUARY

Client: Cuddalore Power Company Ltd.

9

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.3 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF FEBRURAY

Client: Cuddalore Power Company Ltd.

10

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.4 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF MARCH

Client: Cuddalore Power Company Ltd.

11

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.5 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF APRIL

Client: Cuddalore Power Company Ltd.

12

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.6 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF MAY Client: Cuddalore Power Company Ltd.

13

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.7 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF JUNE Client: Cuddalore Power Company Ltd.

14

Report on open sea coal handling jetty Off cuddalore coast

Client: Cuddalore Power Company Ltd.

Department of ocean engineering IITMadras

15

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.8 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF JULY

Client: Cuddalore Power Company Ltd.

16

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.9 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF AUGUST

Client: Cuddalore Power Company Ltd.

17

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.10 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF SEPTEMBER

Client: Cuddalore Power Company Ltd.

18

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.11 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF OCTOBER

Client: Cuddalore Power Company Ltd.

19

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.12 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF NOVEMBER

Client: Cuddalore Power Company Ltd.

20

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.13 WAVE HEIGHT ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF DECEMBER

Client: Cuddalore Power Company Ltd.

21

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.14 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF JANUARY

Client: Cuddalore Power Company Ltd.

22

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.15 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF FEBRUARY

Client: Cuddalore Power Company Ltd.

23

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.16 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF MARCH

Client: Cuddalore Power Company Ltd.

24

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.17 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF APRIL

Fig.18 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF MAY Client: Cuddalore Power Company Ltd.

25

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.19 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF JUNE Client: Cuddalore Power Company Ltd.

26

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.20 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF JULY Client: Cuddalore Power Company Ltd.

27

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.21 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF AUGUST

Client: Cuddalore Power Company Ltd.

28

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.22 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF SEPTEMBER

Client: Cuddalore Power Company Ltd.

29

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.23 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF OCTOBER Client: Cuddalore Power Company Ltd.

30

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.24 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF NOVEMBER

Client: Cuddalore Power Company Ltd.

31

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig.25 WAVE PERIOD ROSE DIAGRAM OF GRID 4 FOR THE MONTH OF DECEMBER

Client: Cuddalore Power Company Ltd.

32

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig. 26. Significant wave Height (m) May ‘98

Fig. 27. Average Wave Direction (Deg) May ‘98

Client: Cuddalore Power Company Ltd.

33

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig. 28. Zero Crossing Period (s) May ‘98

Fig. 29. Significant Wave Height (m) October’98

Client: Cuddalore Power Company Ltd.

34

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig. 30. Average Wave direction (deg) October’98

Fig. 31. Zero Crossing Period (s) October’98

Client: Cuddalore Power Company Ltd.

35

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig. 32. Average Wave Direction (deg) May’98 – March’99

Fig. 33. Zero Crossing Period (s) May’98 – March’99

Client: Cuddalore Power Company Ltd.

36

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig. 34. Significant Wave height (m) May’98 – March ‘99

Client: Cuddalore Power Company Ltd.

37

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Fig. 35. Cyclones per year.

Client: Cuddalore Power Company Ltd.

38

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

3.0 LITTORAL DRIFT Along the east coast of India, the sea bed is in general sandy. On an average, one million cubic meter of sediment is transported from the south to north over a year. The onshore- offshore transport of sediment is also considerable during hostile wave environment. In the surf zone, where wave breaking occurs most of the time, the onshore-offshore movement of sediments and littoral transport are significant. During severe cyclonic conditions sea bed upto 2m deep can be eroded and transported to the deeper portions of the ocean. Since the littoral transport phenomena are significant in the surf zone (for a coastal width of about 400m) only, it will not effect the coal unloading operations significantly. However, since capital dredging is involved around the unloading pier upto -15.0 m elevation, and natural sea bed is disturbed, slow accretion of sediments around this area is expected to take place. The maintenance dredging requirements can be assumed to be about 5% of capital dredging near the main jetty and turning circle. 4.0 DETAILS OF THE JETTY The proposed unloading terminal consists of an approach jetty for 1250m length and two unloading piers at the end of the approach jetty. Width of the approach jetty is 16 m and three rows of piles are located at a spacing of 8m c/c in the transverse direction. The deck slab is supported by longitudinal and transverse beams. They are supported by piles of 1.2m dia with spacing of 6m c/c in longitudinal direction. Unloading pier has the dimension of 640 m length and 30 m width. Two vessels of 65000 DWT can be berthed at a time and unloaded from one side of the pier only. It has 5 rows of piles at a spacing of 7.5m c/c in the transverse direction. The deck slab is supported by longitudinal and transverse beams. They are supported by piles of 1.2m dia with the spacing of 6m c/c in longitudinal direction. Longitudinal and main beam may be the size of 1200mm x 1500mm. The unloading pier is connected by the approach jetty. The coal will be elevated from the vessel to the belt conveyors by Grab unloaders and is transported to the shore by belt conveyors. The Grab unloaders are mounted on rails on the deck slab of the unloading pier. The maximum size of the vessel considered for the design is 65,000 DWT. Hence the jetty can be conveniently used for vessels of capacity less than 65000 DWT

Client: Cuddalore Power Company Ltd.

39

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

Table 5. Details of the jetty APPROACH JETTY

LENGTH OF ZONE m

Zone I Zone II Zone III Zone IV

200 400 400 250

DIA OF PILE

LENGTH OF PILE

(mm) 1200 1200 1600 1600

(m) 15 21 28 30

The piles in the approach jetty will be founded at different depths depending upon the sea bed profile and marine bore hole details in the location, Likewise, the piles of the main jetty will also be founded depending upon the marine bore hole details. Table 5 provides the location and details of jetty at various stretches from shore end to seaward end. However, a detailed analysis and design is needed to obtain the exact diameter, spacing between the piles, length of the piles and deck slab details. In the drawing along with the report the jetty was located at an angle of 1200 North. Now it is proposed to revise the orientation of the jetty to 1350 North which will be in the direction of predominant waves occurring in the location. 5.0REALIGNMENT OF APPROCH CHANNEL & TURNING CIRCLE As per the original scheme, it was proposed to locate the turning circle and approach channel normal to the shore line. These locations were fixed without taking into the consideration of the proposed offshore marine terminal north of this facility by M/S Chemplast Sanmar Pvt ltd (CSPL). Since the approach channel and turning circle of the terminal will interfere with that of CSPL terminal, it is proposed to shift the location of the approach channel and turning circle suitably towards south thereby avoiding the interference with CSPL facility. As per IS 4651-Part V the diameter of the turning circle should be four times the length of the largest ship(to be berthed in the jetty) with out the tug assistance and this diameter is indicated in the report . In this connection it is pointed out that the diameter of the turning circle could be reduced two times the length of the largest ship with tug assistance. Length of the approach channel is 4.1km (From starting point of turning circle to -15m contour). 6.0 PORT LIMIT The port limit has defined as follows

Client: Cuddalore Power Company Ltd.

40

Report on open sea coal handling jetty Off cuddalore coast

a)

Department of ocean engineering IITMadras

Bounded on west by Coastal high water line connecting two points one ie., A point on north with latitude and longitude of 11038’20”N, 790 45’52”E. and one ie., D point on south with latitude and longitude of 11035’39”N, 790 45’28”E

b)

On east bounded by a line connecting north land point (A) with a latitude and longitude of 11038’20”N, 790 45’52”E on the shore and east in the Bay of Bengal ie., B point with latitude and longitude of 11038’21.128”N, 790 50’33.212”E

c)

Bounded on east by point B with latitude and longitude of 11038’21.128”N, 790 50’33.212”E in the Bay of Bengal and point C with latitude and longitude of 11035’41”N, 790 50’34”E.

d)

Bounded on south by point C with latitude and longitude of 11035’41”N, 790 50’34”E and a point D on land with latitude and longitude of 11035’39”N, 790 45’28”E

6. A. ESTIMATION FOR TWO BERTHS ESTIMATION FOR OFFSHORE JETTY Client: Cuddalore Power Company Ltd.

41

Report on open sea coal handling jetty Off cuddalore coast

Sl no

1 2 3. 4.

Department of ocean engineering IITMadras

Description

Total Length in 'm'

Rate per m length(Rs)

Amount (Rs)

Approach Jetty Unloading Pier

1250 640

300000 850000

375,000,000 544,000,000

4 nos

300,000,000

1,200,000,000

Unloader Conveyor system

1890+500=2390

1,50,000 358,500,000 Total Amount (Rs) 2,477 ,500,000

ESTIMATION FOR CAPITAL DREDGING Sl no

1 2

Description

Quantity Cum.

Rate per Cum(Rs)

Amount (Rs)

200

710,000,000

200

973,000,000 1,683 ,000,000

Turning Circle 3,550,000 Approach Channel + Near Jetty 4,855,000 Total Amount (Rs)

ESTIMATION FOR TUGS & PILOT BOAT Sl.No 1 2

Description Tugs (Approximately 45T Bollard pull) Pilot Boat Total Amount SUMMARY:

Nos 2 1

Amount 600,000,000 20,000,000 620,000,000

Sl no

Description

Amount (Rs)

1 2

Construction of offshore jetty Capital Dredging

2,477 ,500,000 1,683 ,000,000

3

Tugs and Pilot Boat

620,000,000

Total Amount (Rs)

4,780 ,500,000

6. B. ESTIMATION FOR ONE BERTH ESTIMATION FOR OFFSHORE JETTY Sl no

1 2 3. 4.

Description

Total Length in 'm'

Rate per m length(Rs)

Amount (Rs)

Approach Jetty Unloading Pier

1250 350

300000 850000

375,000,000 297,500,000

300,000,000

600,000,000

Unloader 2 nos Conveyor system 1250+350+500=2100

1,50,000 Total Amount (Rs)

315,000,000 1,587 ,500,000

ESTIMATION FOR CAPITAL DREDGING Sl no

1 2

Description

Quantity Cum.

Turning Circle 3,550,000 Approach Channel + Near Jetty 4,855,000 Total Amount (Rs)

Client: Cuddalore Power Company Ltd.

Rate per Cum(Rs)

Amount (Rs)

200

710,000,000

200

973,000,000 1,683 ,000,000

42

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

ESTIMATION FOR TUGS & PILOT BOAT Sl.No 1 2

Description Tugs (Approximately 45T Bollard pull) Pilot Boat Total Amount SUMMARY:

Nos 2 1

Amount 600,000,000 20,000,000 620,000,000

Sl no

Description

Amount (Rs)

1 2

Construction of offshore jetty Capital Dredging

1,587 ,500,000 1,683 ,000,000

3

Tugs and Pilot Boat Total Amount (Rs)

Client: Cuddalore Power Company Ltd.

620,000,000 3,890 ,500,000

43

Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

6.0 SUMMARY The feasibility study has been done for the following two cases. 1. Option A – For two berths at an offshore location 2. Option B – For one berth at an offshore location 1.0 Total length of the jetty for Option A is about 1890m and for Option B is about 1600m. Both options consists of an approach Jetty for 1250m and a unloading pier jetty of 640m length for option A and 350m length for Option B . The width of the approach jetty is about 16m and the unloading pier width is about 30 m. The unloading pier will be located in the dredged water depth of 15m width its deck level at +7.0m for effective berthing and mooring requirements. The seaward end of the approach jetty will be at 10.0 m natural water depth. The top deck level of the approach jetty at the seaward end and shoreward end may be at +7.0m above chart datum to avoid frequent wave slamming. Piles of 1.2m and 1.6m diameter may be used. 2.0 A capital dredging of about 5.925 million cubic meters is involved for the turning circle and approach channel. Since the turning circle is well away from the surf zone only minimum annual maintenance dredging of the order of 5% of the capital dredging will be involved around the turning circle & Jetty. 3.0 The significant wave height off the Cuddalore coast is expected to be upto 2.0 m for 80 % of the year, which is the desired upper limit for unloading operation. A directional wave rider buoy can be installed near the unloading pier for continuous data collection and for deciding about day to day operation. 4.0 The approach jetty is to be designed for the maximum sustainable wave height and 10.0 second wave period with a current of 4.0 knots and wind speed of 207kmph. The unloading pier should be designed for the worst conditions governed by the operational loads (berthing and mooring) and severe environmental loads induced by wave, current and wind in the absence of the vessel with the unloading pier.

Client: Cuddalore Power Company Ltd.

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Report on open sea coal handling jetty Off cuddalore coast

Department of ocean engineering IITMadras

7.0 REQUIREMENT FOR DPR For the detailed project report a following studies measurements need to be carried out the detailed design of jetty and the final discussion on main jetty layout and the approach channel orientation will be finalized based on detailed studies. 1. Detailed bathymetry survey up to 20m bottom contours along the stretches at the proposed location. 2. Bore hole details along the approach jetty ,main jetty and approach channel 3. Wave climate near the jetty.

8.0 REFERENCES Neelamani, S. 1996. Feasibility report for an open sea coal handling system off Cuddalore coast. NIO, 1990, Indian Wave Atlas.

Client: Cuddalore Power Company Ltd.

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Report on open sea coal handling jetty Off cuddalore coast

Client: Cuddalore Power Company Ltd.

Department of ocean engineering IITMadras

46