Ak-212-0 Zanjas Para Tuberias

PDVSA ENGINEERING DESIGN MANUAL VOLUMEN 18–II ENGINEERING SPECIFICATION

PDVSA N°

TITLE

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

AK–212–O

1

NOV.93

GENERAL REVISION

11

L.T.

E.J.

A.N.

0

DEC.85

FOR APPROVAL

11

J.S.

J.G.

E.S.

APPD.

APPD.

REV.

DATE

APPD.BY José Gilarranz

E PDVSA, 1983

DESCRIPTION DATE

PAG. REV.

DEC.85 APPD.BY Eduardo Santamaría

DATE

DEC.85

ESPECIALISTAS

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 1 .Menú Principal

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Index 1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 1.2 1.3 1.4

2

Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Work Included . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Work Not Included . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PDVSA References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 2 2 2

2 RIGHT–OF–WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2

2.1 2.2 2.3 2.4 2.5 2.6

Right–of–Way Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Limitations of Right–of Way Width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Special Provisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Right of Ingress and Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contractor’s Responsibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 3 3 3 3 3

3 REGULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3

4 DITCHING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4

4.1 4.2 4.3 4.4 4.5 4.6

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Depth and Width of Ditch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Extra Depth Ditch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hand Ditching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Underground Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Temporary Crossings Over Open Ditch . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 4 5 5 5 6

5 WATER REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6

6 ROCK EXCAVATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6

6.1 6.2 6.3

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Blasting Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Blasting Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 7 8

7 BACKFILLING AND CLEAN–UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9

7.1 7.2

Backfilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clean–Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 10

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 2 .Menú Principal

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GENERAL 1.1

Scope This specification covers the basic requirements for earth work in connection with ditching and backfill operations for pipeline trenching, right of way and cleanup.

1.2

Work Included The operations described herein include, but are not limited to the excavation, mixing, blending, disposing, handling of all excavation, fill and backfill materials for the earth work.

1.3

Work Not Included Not included in this specification are soil samples, geotechnical investigations and surveys.

1.4

PDVSA References The following codes, standards and specifications, including applicable addenda, shall form a part of this specification to the extent specified herein. Site Clearance and General Earthwork AI–211 Earthwork Excavation and Backfill AK–211 Pipeline – Road Crossing H–201–O Contractor’s work shall comply with the following codes when applicable: Covenin 1750 ANSI B31.4 ANSI B31.8

2

“Especificaciones Generales para Edificios” “Liquid Petroleum Transportation Piping Systems”, Latest Edition “Gas Transmission and Distribution Piping Systems”, Latest Edition

RIGHT–OF–WAY 2.1

Right–of–Way Permits Prior to beginning of construction, the PDVSA’s representative will secure right–of–way within which the pipeline will be located and installed. PDVSA shall provide a minimum right–of–way of 30 meters in width; this dimension is subject to modification in case special conditions are found. Contractor will provide the necessary permits for waterway crossings, municipality permits, permits for crossing government lands, longitudinal or crossing permits for roads, and other permits they may be required from certain jurisdictional agencies.

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 3 .Menú Principal

2.2

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Limitations of Right–of Way Width For Contractor’s construction operations, PDVSA’s representative will provide a minimum right–of–way of 30 meters (98 feet) in width.

2.3

Special Provisions Special requirements in the right–of–way permit will be noted on the drawings and line lists furnished to the Contractor. It shall be the Contractor’s responsibility to comply with these special requirements. Unless specified otherwise, Contractor may only use additional temporary work space adjoining the construction right–of–way at road and stream crossing for his operations. Costs for obtaining additional temporary work space and damages that are incurred will be at Contractor’s expense.

2.4

Right of Ingress and Egress The right of ingress and egress to the right–of–way shall be limited to points where right–of–way intersects public roads, unless other access is provided by PDVSA’s representative. Arrangements for other access may be made by Contractor at his expense and with Inspection Authority approval.

2.5

Contractor’s Responsibility Contractor will provide his own space for equipment storage offices, living accomodations, watchmen, etc.

2.6

Markers Contractor shall install the required kilometer post markers and pipeline markers at the locations indicated on the alignment sheets and in accordance with applicable pipeline drawings. Kilometer posts shall be installed at one (1) kilometer intervals along the right–of–way and pipeline markers shall be installed at major road crossings and at locations specified by the PDVSA’s representative. All markers shall be located at or near fences if possible or at convenient locations where they do not interfere with normal land use.

3

REGULATION These specifications are to be used as minimum requirements. If there are any deviations between these specifications and local codes and standards, the local codes and standards shall govern.

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 4 .Menú Principal

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DITCHING 4.1

General Ditching and excavating work shall be in accordance with these specifications and any variations that may become necessary shall be accomplished in a manner to safeguard the third parties. Contractor shall excavate and maintain the ditch in which the pipeline is to be laid. The ditch shall be excavated along the surveyed and staked line established by the PDVSA’s representative in accordance with applicable pipeline drawings. The bottom of the ditch shall be uniformly graded to proper depths to prevent unnecessary bending of the pipe. The ditch may not contain loose rock, large clods and other objects which might damage the pipe or coating. All tree roots shall be cut flush with the sides and the bottom of the ditch to prevent contact with the pipe coating. The spoil from the ditch may not be allowed to fall on any undesirable debris that might be mixed with the soil and backfilled in the ditch. Spoil banks from any ditching operations may not be placed where natural drainage will be impaired. Spoil banks shall be placed in a manner acceptable to the PDVSA’s representative.

4.2

Depth and Width of Ditch On long sections excavated by ditching machines, the minimum width of the ditch shall be 305 mm (12 in) greater than the outside diameter of the coated pipe. Unless otherwise shown on the drawings, sections where there are two (2) or more parallel lines, a common ditch may be used in which the minimum spacing between the centers of parallel lines shall be at least 1.200 mm (48 in) and the minimum ditch width shall be 305 mm (12 in) plus the sum of the outside diameters of the parallel lines plus the spacing between the parallel lines. If Contractor elects to provide a separate ditch for each parallel line, there will be no additional cost to PDVSA’s representative. The ditch shall be of sufficient depth to provide a minimum cover over the coated pipe in normal soil of 760 mm (30 in) and a minimum cover over concrete weights, where installed, of 1200 mm (48 in) below the normal ground surface. A minimum cover in normal soil of 900 mm (36 in) below the normal ground surface shall be provided inside the fence limits of compressor and pump stations, mainline valve settings and plant facilities. See Covenin 1750 for ditch width according to pipe diameters.

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 5 .Menú Principal

4.3

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Extra Depth Ditch Extra depth that is required to provide cover in excess of that specified is defined as extra depth ditch. The Contractor shall, without additional compensation, provide extra depth ditch at locations where, in the opinion of the PDVSA’s representative, extra depth is necessary to insure proper installation of the pipeline. These locations include crossings and approaches of existing roads, ditches, rivers, existing underground pipelines or utility crossings, and at other locations where the contour of the earth requires extra depth ditch to prevent unnecessary bending of the pipe. Where required by these Specifications or shown on the drawings, the Contractor shall provide extra ditch without additional compensation. When the PDVSA’s representative requires extra depth ditch in excess of that specified depth above, the Contractor shall provide the required extra depth ditch and will receive additional compensation in accordance with the price quotation schedule. If the standard ditch excavation has been previously completed, Contractor will be compensated for the actual time spent in moving the required excavating equipment back to the respective location requiring extra depth ditch. When Contractor’s excavation equipment has not completed the standard depth excavation, the additional compensation that the Contractor will receive for extra depth ditch will be computed by in cubic meters. The actual extra depth ditch will be computed by in cubic meters. The actual extra depth ditch excavation to be paid for will be computed by multiplying the length of extra depth ditch by the extra depth by the width of ditch.

4.4

Hand Ditching At locations where, in the PDVSA’s representative opinion, the use of ditching equipment may cause unnecessary damage to below–ground facilities crossed by the right–of–way, or where required in these Specifications, Contractor may be required to excavate the ditch by hand. Contractor will not be given extra compensation for hand ditching.

4.5

Underground Structures Where ditching operations parallel or cross existing underground facilities, Contractor shall exercise care to prevent damage to these facilities. Contractor shall give proper notification to PDVSA’s representative and to the respective authorities having jurisdiction over the facilities prior to the beginning of Contractor’s excavation. These crossings shall be governed by the requirements of the respective authority having jurisdiction over the facility. Contractor shall, with PDVSA’s representative and authorities having jurisdiction approval, completely expose the underground facility by hand excavation before starting machine excavation. Respective authorities may require their facilities to be

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 6 .Menú Principal

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exposed by their own employees before Contractor begins any ditching or boring near their facilities. Unless required otherwise, Contractor shall provide a required ditch depth to permit installation of the pipeline below the existing facility with a minimum of 30 cm (1 ft) clearance. If the facility exists at a depth that would cause the installation to be impractical and permission is granted to PDVSA’s representative by the respective authority, Contractor may install the pipeline above the facility. If Contractor damages an underground facility, the owner of the facility and PDVSA’s representative shall be contacted immediately. The repairs to the facility shall be made at Contractor’s expense and to the satisfaction of the owner. When ditching operations parallel an existing pipeline, the spoil bank shall be placed at a location where the subsequent construction operations may be accomplished without operating heavy equipment over the existing pipeline.

4.6

Temporary Crossings Over Open Ditch Contractor shall provide safe temporary bridges over the open ditch where necessary to permit passage of personnel and equipment.

5

6

WATER REMOVAL 5.1

Provision shall be made to keep the excavation dry and to remove any water which may accumulate in the excavations. No manhole, concrete structure, or sewer pipe shall be installed in water.

5.2

Water shall be removed from opened trenches by pumping or other methods approved by PDVSA’s representative and shall be discharged to natural drainage courses, plant ditches or other sewers, in such a manner that other work areas will not be affected.

5.3

All dewatering systems shall remain in operating until the installation they protect, including backfill about it, is in place and all permanent drainage systems are operational.

5.4

Where excavations will extend below the groundwater table, advance dewatering shall be performed and maintained so that the water level shall not be less than 760 mm (30 in) below the bottom of the excavation so that any required foundations can be placed in the dry and on stable, undisturbed subgrade.

ROCK EXCAVATION 6.1

General In areas where rock is encountered, the ditch shall be excavated to provide a minimum 610 mm (24 in) of cover over the pipeline with 250 mm (10 in) of earth

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 7 .Menú Principal

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or sand padding under and around the pipe. The ditch padding shall be at the Contractor’s expense. PDVSA’s representative will determine which areas require a rock excavation procedure. Rock excavation will be defined as those areas which pneumatic hammer, boring, angering, wedging or blasting are continuously and systematically required. If a rock excavation procedure is required, the Contractor shall be paid for this work at the unit price stipulated for rock excavation. Unless otherwise indicated, the rock excavation unit price shall not include the furnishing and placing of a suitable padding and backfill material. The quantity of rock removed shall be computed using the following dimensions: depth – top of rock to specified trench ditch; width – as specified; length – actual measured length.

6.2

Blasting Operations Where blasting is required and approved by PDVSA’s representative for rock excavation, Contractor shall exercise extreme care and shall use PDVSA’s representative approved methods which prevent damage to property adjacent to pipeline right–of–way and insures public safety. Contractor shall take every precaution to protect the public and its workmen from injury or harm which might arise from the use of explosives. Blasting mats or other effective means shall be used to prevent rock from being scattered over the right–of–way and adjacent property, any rock that is scattered shall be picked up by Contractor and disposed of to the satisfaction of PDVSA’s representative. Contractor’s blasting operations shall conform with all legal requirements in connection with the use of explosives anywhere in the work. Unless otherwise designated in the specifications, Contractor shall secure all necessary permits. To obtain approval to blast, the Contractor shall submit to PDVSA’s representative, a written description of the following information: – The type, characteristics, and quantity of the explosive which Contractor proposes to use. – The proposed methods for transporting, storing, hauling, and using such explosives. – The safety procedures proposed to be followed including matting or other protective materials signs and warning devices to be used. – The qualifications and permits held by Contractor’s employees who shall be directly responsible for handling and using such explosives. – The location(s) where Contractor proposes to carry out blasting operations. – The proposed location of magazines and other storage facilities for explosives and detonators. – The dates and hours during which Contractor proposes to carry out blasting operations.

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 8 .Menú Principal

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Only workmen thoroughly experienced in handling explosives shall be permitted to supervise, handle, haul, load and detonate explosives. All blasting operations including the detonation of any placed charges, shall be restricted to daylight hours. The method of storing all explosives shall be approved by PDVSA’s representative Proper disposal of all explosive containers and used materials shall be made by Contractor in a manner satisfactory to PDVSA’s representative. Blasting complaints submitted to the Contractor by the public shall be reported to PDVSA’s representative within 24 hours of receipt. Reports shall include the name and address of the person making the complaint, date and time received, date and time of the subject blast, and a brief description of the alleged damages or other circumstances upon which the complaint is made. A report shall be submitted to PDVSA’s representative by Contractor which indicates the date, time, the name of person investigating the complaint, recommendations concerning the validity of the complaint, the amount of damages claimed and the amount of settlement. All damage claims shall be settled by the Contractor at his expense. When a claim is settled, PDVSA’s representative shall furnish a copy of the claim release by the Claimant.

6.3

Blasting Records Contractor shall maintain a record log which is to be available at all times to PDVSA’s representative. These records shall include the following data on each blast: – Plan of the blast hole spacings, depths and the location of the blast point in relation to survey stations. – Drilling record showing any unusual joint or seam conditions encountered in the rock. – Type of strength of explosives, blasting caps, and delays. – Total explosive loadings per round and per group of delays. – Comments by blaster in charge regarding any misfires, unusual results or effects. – Prevailing weather conditions, including direction and approximate velocity of wind, ambient temperature, relative humidity, and cloud conditions at the time of blast. – Date and exact firing time of blast. – Name of person responsible for loading and firing; blast permit number when permit is required. – Signature and title of person making record entries.

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 9 .Menú Principal

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BACKFILLING AND CLEAN–UP 7.1

Backfilling After lowering in has been completed, but before backfilling, the line shall be inspected to insure that timbers, brush, stumps, trees, boulders or other debris are not in the ditch or on the spoil bank. This material may not be used as backfill. Backfilling of the ditch and grading of the right–of–way shall be done in a manner that restores the natural contour of the ground and allows normal surface drainage. Spoil that cannot be used in the backfill shall be considered as surplus and shall be removed from the premises by Contractor. Contractor shall dispose of spoil in a manner and at suitable locations satisfactory to PDVSA’s representative.

7.1.1

Backfilling across roads and streams shall be done by Contractor in a manner satisfactory to all jurisdictional agencies.

7.1.2

All ditches cut across roads shall be backfilled immediately after installation of the pipe or casing in 150 mm (6 in) lifts and each lift shall be thoroughly hand or machine compacted. At all road crossings, Contractor shall provide danger signs that are visible during daylight and at night provide lights or flares placed in a manner prescribed by the jurisdictional agency. Compaction shall be performed according to Covenin 1750.

7.1.3

Rock may not be placed in the backfill at elevations higher than the average of rock in the adjacent undisturbed areas. On cultivated land, rock may not be placed in the backfill within 300 mm (one foot) of the surface of the original soil or within 150 mm (6 in) of the top of the pipe. If sufficient space between the 150 mm (6 in) layer of soil over the pipe and a point 300 mm (1 ft) below the surface of the original soil is not available, the rock shall be disposed of at Contractor’s expense off the right–of–way and to the satisfaction of PDVSA’s representative.

7.1.4

If damage occurs as a result of sharp or hard objets falling into the pipeline during backfilling operations, Contractor shall be responsible for any repairs to damaged pipe or coating at his expense.

7.1.5

At the end of each day’s work, the open ends of all pipe shall be raised and placed on timbers above the ditch and the ends securely covered to prevent the entrance of small animals, water and debris. The ends may not be reopened until the work begins the following day. End covers shall be of the same diameters as the pipe and placed over the open ends of the tie–in sections, or both ends of long sections. Any obstructions which may occur in the line shall be removed by Contractor at his expense and to the satisfaction of PDVSA’s representative.

7.1.6

All locations where Contractor has moved earth to facilitate the movement and operation of his equipment, shall be restored by Contractor to their original condition.

ENGINEERING SPECIFICATION

PDVSA

PIPELINE TRENCHING AND RIGHT OF WAY AND CLEAN–UP

PDVSA AK–212–O REVISION

FECHA

1

NOV.93

Página 10 .Menú Principal

7.1.7

7.2

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Where, in the opinion of PDVSA’s representative, the backfill is endangered by possible erosion, breakers constructed with earth–filled sacks or other materials shall be placed in the ditch.

Clean–Up

7.2.1

Contractor shall keep the right–of–way clear of barrels, timber, defective materials, coating material waste, stubs of welding rods and all other construction debris immediately behind its operations, to the satisfaction of PDVSA,s representative.

7.2.2

All clean–up shall be maintained by PDVSA,s representative.

7.2.3

After clean–up operations are completed and approved, if Contractor is required to perform any operation(s) due to leak or failure, the Contractor shall be responsible for restoring the final clean–up to the satisfaction of the PDVSA,s representative.

7.2.4

Fences disturbed by construction shall be restored to their original condition in accordance with applicable drawings and to the satisfaction of the PDVSA,s representative.

7.2.5

Private roads used by Contractor shall be restored to former condition to the satisfaction of the PDVSA,s representative and governing jurisdiction.

7.2.6

The banks of all stream shall be restored to their former elevations and grade. All debris and obstructions resulting from construction of the pipeline, shall be removed from the crossings to prevent interferences with normal water flow. Disposal of such material shall be subject to PDVSA’s representative approval.

7.2.7

At locations such as sloping terrain and stream crossings, the Contractor shall furnish and place suitable sack breakers in and at an angle across the pipe trench as necessary to prevent erosion of the trench backfill, sloping banks of streams, and roads. The sacks for breakers shall be filled as indicated in 1.7.1. The type of sacks and locations of their installation shall be subject to PDVSA’s representative approval. Contractor will be paid for furnishing and installing sack breakers on a unit basis.