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British Columbia

CONSTRUCTION CRAFT WORKERAPPRENTICESHIP PROGRAM

Local 1611

LINE I Perform Utilities and Pipeline Tasks

LEVEL 2

CONSTRUCTION CRAFT WORKER APPRENTICESHIP PROGRAMLEVEL 2

Line I: Perform Utilities and Pipeline Tasks

Acknowledgements & Copyright Permission© 2017 Industry Training Authority

This publication may not be reproduced in any form without written permission by the Industry Training Authority.

Version 1 May 2017

The Industry Training Authority is under a licensing agreement with LiUNA (Labourers International Union of North American) Local 1611 to use their Construction Craft Workers Level 1 and Level 2 training materials throughout British Columbia and Canada. The Industry Training Authority would like to thank LiUNA for making these materials available.

Construction and Specialized Workers Training SocietyThese materials were initially developed for the first classes of Apprenticeship.

Level 2 by the Construction and Specialized Workers Training Society (CSWTS) in January of 2015 (British Columbia).

Those originally responsible for the manual:

• Manuel Alvernaz; Chairman of the Construction and Specialized Workers Training Society (CSWTS)

• Fred Webber; PID, Red Seal Journeyperson, Administrator and Senior Instructor (CSWTS)

• Tom Miller; PID, Red Seal Journeyperson, Instructor (CSWTS)

• Jeffrey Anders; BSc, BA, Red Seal Journeyperson, Special International and Trifunds Representative (LIUNA)

Open School BCOpen School BC sourced all the images and updated the layout (2016/17).Solvig Norman, Project Manager Monique Brewer, DirectorJennifer Riddel, Manager of Instructional ServicesDennis Evans, Production Technician (print layout, image researcher, photographer & illustrations)Max Licht, IllustratorAndrei Antica, photographerShannon Sangster, Office Manager (copyright permissions)

Copyright PermissionWikimedia Commons: Pig Head Swiveled Left.JPG – Author: Leonard G.Wikimedia Commons: PigTractor.JPG – Author: Leonard G.Wikimedia Commons: Shrinking Sleeves.JPG – Author: VsolymossyWikimedia Commons: Silt fence.JPG- Author: USA Environmental Protection AgencyWikimedia Commons: Blasting crew preparing site.JPG – Author: US Army Corps of Engineers Sacramento District“Brush Chipper and directional drilling” used with permission from Vermeer.Some images were licensed from Thinkstock.

CONSTRUCTION CRAFT WORKER APPRENTICESHIP PROGRAM—LEVEL 2 3

ContentsForeword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Program Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Competency I1: Install Utility Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Types of pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Installation of piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Pipe repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Testing water and sewer lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Competency I2: Perform Pipeline Activities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Construction of pipeline right of ways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Environmental considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Governmental regulations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Clearing brush . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Clearance markers and signage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Pipeline installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Competency I3: Perform Pipeline Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Pipeline testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Pipe protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

4 CONSTRUCTION CRAFT WORKER APPRENTICESHIP PROGRAM—LEVEL 2

DisclaimerThe materials in these Learning Guides are for use by students and instructional staff, and have been compiled from sources believed to be reliable and to represent best current opinions on these subjects. These manuals are intended to serve as a starting point for good practices and may not specify all minimum legal standards. No warranty, guarantee or representation is made by the British Columbia Industry Training Authority or the Queen’s Printer of British Columbia as to the accuracy or sufficiency of the information contained in these publications. These manuals are intended to provide basic guidelines for Construction Craft Worker practices. Do not assume, therefore, that all necessary warnings and safety precautionary measures are contained in this Competency and that other or additional measures may not be required.

Safety AdvisoryBe advised that references to the Workers’ Compensation Board of British Columbia safety regulations contained within these materials do not/may not reflect the most recent Occupational Health and Safety Regulation. The current Standards and Regulation in BC can be obtained at the following website: http://www.worksafebc.com.

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ForewordConstruction Craft Workers, also known as labourers, work mostly on construction sites. Their tasks include:

• Site preparation and cleanup.• Set up and remove access equipment.• Work on concrete and masonry, steel, wood and pre-cast erecting projects.• Handle materials and equipment• Perform demolition, excavation, and compaction activities.• Ensure site security.

Construction Craft Workers (CCWs) work on a wide variety of structures such as residential, commercial and industrial buildings, as well as hydro-electric dams, roadways, bridges and railways. In some jurisdictions, they also work on utility, landscape, and pipeline projects. CCWs work for private companies as well as municipal, provincial, and federal governments.

With experience, CCWs who complete additional training specialize in different areas of construction. This includes operating off-road vehicles, drilling and blasting, diving, tunneling, rock scaling, performing emergency rescue, and the management of pedestrian and vehicular traffic in situations involving potential hazards and public trust.

CCWs work primarily outdoors in all weather conditions. They are often required to work at heights, over water, in confined spaces, and excavations. Their job settings are in densely populated urban settings or in remote locations. They often work overtime during peak construction periods.

Key attributes for CCWs are mechanical aptitude, manual dexterity and an ability to do hard, physical work. They must also be able to work as team members and to interact directly with the public where such considerations as safety and legal liability are issues. Organizational leadership and blueprint reading skills are assets for anyone wanting to progress in this trade. With experience and training, CCWs can advance to supervisory/foreman positions.

Program OutlineLevel 1Line A: Use Safe Work PracticesLine B: Organize WorkLine C: Use Tools and EquipmentLine D: Perform Routine Trade ActivitiesLine E: Perform Site WorkLine F: Use Scaffolding and Access EquipmentLine G: Perform Concrete WorkLine I: Perform Utilities and Pipeline TasksLine J: Perform Roadwork

Level 2Line A: Use Safe Work PracticesLine B: Organize WorkLine D: Perform Routine Trade ActivitiesLine E: Perform Site WorkLine F: Use Scaffolding and Access EquipmentLine G: Perform Concrete WorkLine H: Perform Masonry WorkLine I: Perform Utilities and Pipeline Tasks


LINE I: PERFORM UTILITIES ANd PIPELINE TASKS COMPETENCy I1

COMPETENCY I1

Install Utility PipingWhen installing utilities and piping, a crew of people is needed to do the job properly. Aside from the equipment operators, here is a general breakdown of the job titles needed to do the job:

Figure 1 — Installing concrete utility pipe

ForemanResponsible for the safety and performance of his crew and for completion of the project according to the design drawings and specifications.

Lead handWorks closely with the excavator operator to uncover utilities while digging to pipe grade. He also directs the lowering of the pipe and fittings into the trench and is responsible to set the pipe to line and grade.

Pipelayer’s helperCleans and guides the tail end of the pipe during the setting. Assists the lead Pipelayer to set and tamp the pipe and ensures that the pipe is being backfilled correctly.

Top personWatches for trench cave-ins. Cuts and bevels the pipe. Organizes and rigs all of the pipe and fittings to be sent into the trench. Assists with the placement and removal of trench shoring and guides the equipment placing backfill material.



Instrument personWith the use of survey instruments, guides the Construction Craft Worker to set the pipe on line and grade. Checks the design drawings for possible conflicts with existing utilities. Is responsible for the correct excavating and installation of all pipe, fittings, manholes, catch basins, or any other structures. Keeps accurate records of all as-built locations of the pipe, fittings and structures.

Types of pipeUnderground utility systems are classified as either gravity flow systems or pressurized systems. Gravity flow systems consist of piping that is not pressurized and is sloped to allow flow. These systems usually include storm and sanitary sewers. Pressurized piping systems include fire water systems, cooling water systems, potable water systems, and sewer force mains. Other types of utility systems include hydro and communication ducting and that particular piping is not gravity flow or pressurized because they use those pipes as a conduit to run wires through. A wide variety of materials can be used for underground piping systems. The most common are ductile iron, concrete, PVC, and corrugated steel.

Ductile iron pipeDuctile iron pipe is made of cast iron. Ductile iron is used in pressurized water and sewer systems and in certain conditions, non-pressure systems as well. Ductile iron is stronger, more corrosion resistant, and able to withstand greater loads than standard cast iron pipe. Ductile iron pipe is particularly suited for exposed piping systems, mounting on piers, deep cuts, high temperatures, and abrasive flows. These qualities make ductile iron particularly suited to deep underground applications. The life expectancy of this type of pipe is 75 years.

Unless otherwise specified, ductile iron pipe is coated on the outside with a bituminous coating. This type of coating gives the pipe its characteristic flat-black appearance. Ductile iron pipe used for water systems may be lined with cement, lined with a bituminous coating, or unlined. Pipes with inside linings require special handling and care to prevent damage. Lined pipe of any kind should not be handled by a fork, boom, or hook inside the pipe.

Ductile iron (DI) pipe is available in sizes ranging from 8 mm to 1600 mm in diameter and usually comes in 6m lengths. Due to manufacturing tolerances, it is not uncommon to receive DI pipe in lengths other than 6 m. The pipe is manufactured in pressure classes ranging from 150–350 psi, in 50 lb. increments. Each job will have a specific psi rating that will be needed. Other than the psi rating, other information that should be written on the pipe is the manufacturer’s mark, the country it was made, year it was produced, the letters DI or “ductile”, the weight, and the inside diameter.



Concrete pipeConcrete pipe is commonly used in the construction of water, sewer, industrial waste, and storm water systems. Concrete pipe is manufactured for non-pressure applications. There is also two different types of concrete pipe; reinforced concrete pipe and non-reinforced concrete pipe. Reinforced concrete pipe has a steel cage placed in the mold during the casting process where the non-reinforced has nothing. One big advantage of using concrete pipe is that it has a life expectancy of 100 years.

Diameters given for concrete pipe refer to the inside diameters. There are minimum required dimensions and wall thickness for concrete pipe based on standards written by the ASTM. The wall thickness of concrete pipe can vary greatly and there is usually a difference between manufacturers. Since there may be a difference between manufacturers, always check and measure the pipe first yourself before it starts being installed in the ground. Concrete pipe is usually manufactured in 2.5 m lengths and can range in diameters from 300 mm up to 4500 mm. Concrete pipe should be marked with the pipe diameter, the date it was manufactured, and the name or trademark of the manufacturer.

PVC pipePVC pipe is a plastic pipe often used in sanitary, storm, water and other utility systems. In the past few years, the use of plastic pipe has increased significantly. The advantages of plastic pipe are that it is inexpensive, lightweight, easily joined, and corrosion resistant. It has smooth internal walls that do not restrict flow. PVC pipe is manufactured in a wide variety of types and styles for many different applications. One drawback of using PVC pipe is that it only has a lift expectancy of approx. 50 years.

PVC pipe is manufactured in standard dimensions from 10mm and up. It is important to note that the outside diameter is NOT standardized and you must be very careful when selecting fittings. PVC pipe should be marked with the inside diameter, the manufacturer’s name and the dimension ratio. There is also a type of PVC pipe called HDPE which is high density and is used for below ground applications such as drains, foundational drains, house connections and water systems. HDPE pipe is available in solid and ribbed wall styles.



Corrugated steel pipeCorrugated steel pipe is most commonly used in storm drain applications, and is especially suited for heavy load conditions such as under highways and building foundations. Corrugated pipe, also known as helical core pipe, is easily recognized by the spiral appearance of it. In addition to circular pipe, corrugated steel pipe can be manufactured in elliptical, arch, and other shapes as well.

Figure 2 — Corrugated steel pipe

Installation of pipingEach application and each set of circumstances is going to create a slightly different process and set of conditions, but here is a brief description of how pipe should be installed for water mains, storm, and sanitary sewers.

First the trench needs to be dug. This is usually done with a backhoe or an excavator with the aid of the surveyor and lead hand. It is up to everyone involved that the trench is dug in the right location, it is sloped or shored properly, and it is dug to the right grade. When digging a trench, a worker should always be present with the operator to help daylight or spot existing utilities that could be struck or destroyed.

Figure 3 — Labourer assisting operator



After the trench has been dug and is safe to go into, the Pipelayers now enter the trench. Once in the trench they will require bedding material to bed the ditch with. This helps not only to provide a slight barrier for the pipe to sit on, but it also acts as a leveling course to prepare a nice even grade for the pipe. The bedding will be dumped into the trench by a machine with the help of the top man to help direct him. The bedding will be prepared on grade with the help of a surveyor or with a pipe laser.

Figure 4 — Pipeline bedding

Once the trench bedding is in and it has been put on grade, the pipe can now enter the ditch. Generally with smaller, lighter pipe, the top man can manually send the pipe down carefully for the CCW to grab. This must be done with caution and good communication is key. With heavier pipe, a machine will send the pipe down to the operators with the use of a sling of some sort. The pipe must be rigged properly and the worker must communicate to the top man well so that the operator does not lower the pipe down onto a worker.

Figure 5 — Positioning pipe



Once the pipe is in, it is now ready to be set. With bell and spigot pipe (most commonly found), the CCW’s helper will maneuver the spigot end that will be inserted into the previous pipe’s bell. He must make sure that both the bell and spigot are clean, that the bell’s rubber is intact, and that the bell and spigot are lubricated efficiently. The lead hand or head CCW will be at the far (bell) end of the pipe, and he is responsible for making sure that the pipe is on line and on grade. If there is no pipe laser, he needs to communicate with the surveyor as to what to do, and follow his direction. If he is using a pipe laser, he must use the laser beam as his guide for line and grade. With lighter pipe, the lead hand will bar the pipe in, making sure that it is in all the way. With heavier pipe, the lead hand will direct the operator to push the pipe together.

Figure 6 — Directing equipment operator

Now that the pipe is in and on line and grade, it is ready to be tamped. The top man will now direct the operator to dump clear crush rock or sand, usually up to springline on the pipe. Once the material is in, the CCWs will now take a shovel in most cases, and tamp the rock into the voids so that the pipe stays and does not move during the backfill and compaction process. Once the pipe is sufficiently tamped, the initial backfill can be placed, which is usually a road mulch or sand. Specifications will dictate how much needs to go on, but 6" is usually the minimum. The initial backfill is in place so that when the rest of the backfill is placed, no rocks or sharp objects can puncture or oval the pipe.



Once the initial backfill is in place, then the pipe can be completely backfilled. As operators place the native or import material over the pipe, it is up to the CCW’s helper and/or the top man to make sure no rocks are directly over the pipe. If it is a very large rock, it should be pulled out of the trench, while smaller rocks can usually just get rolled to the side of the trench. The lead CCW does not usually take part in this process because they are usually with a machine operator digging the trench for the next length of pipe.

Figure 7 — Backfilling over pipe

Pipe repairsThere are various reasons why a utility line may have to be repaired or modified. Utility piping does not last forever and over time, conditions may change and pieces may deteriorate. Whether it is rubber gaskets, valves, or the pipe itself, there are many avenues for where pipe may leak out. Also, during the installation or backfill process, sometimes pieces may become damaged or faulty, and they eventually need to be fixed as well.

Figure 8 — Bursted utility pipe



LeaksLeaks can be a major concern with piping, no matter what the application is. Piping is designed to transport the water, sanitary waste, or gas without letting any of those materials out, so whenever a leak occurs it needs to be fixed swiftly and properly. With storm and sanitary lines, because they are not pressurized and often do not produce a heavy flow, they can often be repaired on live lines with no problems. Once the problem is found, that section is cut out and a new piece of pipe with new couplers is placed as the repair. With water lines, the same sort of procedure is followed but one needs to make sure that the line is not pressurized first; if the line is pressurized then other procedures need to be followed.

AdditionsAdditions often times need to be installed on utility runs as well. Sometimes new lines are designed that run perpendicular off of old mains, or sometimes new valves, manholes or utility components need to be installed. With tie-ins on gravity flow lines, if the flow is low the tie-in can be done quite seamlessly. It there is a heavier flow, sometimes damning, collection, or pumping of the material needs to happen upstream to give the workers time and the ability to do the addition properly. With pressurized water lines, depending on the addition, special procedures and equipment are used. One example is a Hot Tap machine. A Hot Tap is defined as using a drilling machine to cut a hole into a pressurized line while it is under pressure. This is done without any service interruption or leakage. Components needed to perform a Hot Tap normally include a fitting designed to contain system pressure, a valve used to control the new connection and a drilling or tapping machine.

Also during repairs or additions, sometimes a section needs to be isolated. This can be done using a bladder. A bladder starts like an uninflated balloon. It is attached to a hose and inserted into a pipe to help drain or isolate the sections of pipe. When the pressure is turned on the bladder inflates and wedges itself in the pipe, isolating an area. A bladder is often times also called a plug and it is important to test the bladder first before each use.

Depending on the repair or modification that is needed, there are many different materials that are often used to help aid that process. Here are a few of the resources used:

• Spray foam is a non-toxic polyurethane foam that is sometimes used to help restrict the entry of cold air during the winter months and hot air during the summer months. It can also be used to keep heat in particular lines like steam lines. It is sprayed from the tip of a gun and it expands after it is sprayed which eventually hardens upon drying.

• Coatings are used primarily on pipelines after finding a holiday. Most pipeline pipes come with a coating already placed but sometimes during transport the coating can become damaged. In these cases an extra coating will have to be placed on these damaged areas (more discussed in the pipeline section).

• Quick set concrete (Quickrete®) is a cement based formula that is specially formulated for making structural repairs to vertical and overhead services. It is used anywhere that



rapid setting is necessary and is used to repair concrete pipes, sewers, culverts, catch basins or septic tanks as well as many other non-utility based applications.

• Clamps are emergency bolt-on style fittings for high or low pressure services. Sometimes leaks occur in these pressurized systems due to damage over time, during transportation or during distribution and the existing gaskets and o-rings may fail. These clamps made for leak repairs for pipe, tees, flanges and valves can come in standard configurations or can be custom designed.

Figure 9 — Repair clamp

• Mechanical joints can be used on water mains rather than flanges and they can be used to help keep the joints together. One side of the joint is fastened to the other side and sometimes even those joints can be tied-back with ready rod to help prevent the joints from spreading apart. Mechanical joints also offer a bit more deflection than regular flanges.

Figure 10 — Mechanical coupling



• Couplers, slip collars and ro-bars are common pieces used to repair leaks on storm, sanitary and water lines. Couplers and slip collars are used when a section of PVC pipe is cut out and needs to be replaced. Ro-bars are used on pressurized water lines and they are used on a repair as well.

When repairing or modifying existing piping, there can be some hazardous material in play. If repairing older lines, workers may come into contact with asbestos or lead. For many years asbestos lined piping was used for water mains. They are never installed anymore but some municipalities still have asbestos water main in the ground so special measures need to be taken if working around those pipes. Lead pipe is much less common as it has not been used for a lengthy period of time, but if working around lead piping, let your supervisor know and then it should be dealt with in a proper manner.

Testing water and sewer linesWhen testing storm and sanitary lines, the first step that is generally taken is that the lines are completely flushed out. During the construction process, these lines tend to accumulate with dirt and gravel and to accurately assess those lines, they need to be clean of debris. Once this step is done, usually a camera truck is brought in to video the lines. This video can tell if any pipe is oval in shape, if there are any cracks, if there is any large deflection in the pipe, or if there is any back fall. Due to the fact that the lines were just flushed, a very amount of water should be left in the lines because they are clean and gravity should take the water away. If there are any large ponds, then the camera can see them and assess that there is back fall in that spot. Sometimes a mandrel is still used to pull through the lines. This is a device that is usually approx. 90% capacity of the pipe and allows for approximately 6–7% deflection at any joint. The mandrel will be able to tell if there are any large deflections or any oval-shaped pipe because it will not be able to pull through if there are.

Figure 11 — Pipeline video inspection equipment



Once this is done, that is usually sufficient enough for storm piping. If there any small leaks in storm piping it is not usually a big deal because any residual water then evacuates the pipe just makes its way back into the earth. The same cannot be said for sanitary piping. To test sanitary lines for leaks, usually a bladder or plug is placed down a manhole at each end of a line and then it is air pressure tested. If over a period of time the pressure does not stay at a predetermined amount, then there is a leak most likely at a joint somewhere and that will have to be dug up and fixed.

Testing water lines is a different procedure entirely. Now you are dealing with pressurized water and that requires more care and attention than gravity flow lines. The general test used is a hydrostatic test. This test involves charging the line full of water at a higher pressure than it will actually be pressurized at during operation and then letting it sit for 2 hours. If the line stays at the desired pressure then the line is free of leaks. If the pressure drops within those 2 hours then the leak needs to be located and fixed.

Sometimes during this test, the water that is placed into the main has a dye in it as well to help locate the leak. To locate the leak, valves will be opened and closed and tested in sections to segregate an area to help narrow down the possibility field. Once a section has been determined to be the problem, joints are then dug up. Usually the problem is at a valve or bends because those tend to be the more problem areas but not always. For larger leaks, you can see water spurning out along with the colored dye, but with smaller leaks you sometimes have to listen for a hiss or look for a small amount of bubbling at the joint. This can be a tedious process but it needs to be done.

Chlorine is used during hydrostatic testing to eliminate any bacteria that may have entered the main during construction. It is also used in most water systems for the same reason. However, during testing, a much higher concentration of chlorine is used—too much for drinking water. So, after pressure and leakage testing is complete, the main is flushed of chlorine down to the background readings of the existing system (the target level is 0.2 ppm of chlorine). Then samples are taken for coliform (a bacteria that can enter the main during construction), water colour, odour, turbidity (cloudiness), and pH. Sometimes, you will also need to test for volatile organic compounds.

The next step is main flushing with dechlorination of waste water used for testing. A dechlorination device designed to achieve dechlorination requirements specified in the project documents, must be used during the discharge of waste water from the main. When all waste water has been flushed from the main, the mainline and hydrants are put into service.



COMPETENCY I2

Perform Pipeline Activities

Construction of pipeline right of waysA right-of-way is the legal right, established by usage or grant, to pass along a specific route through grounds or property belonging to another. Pipeline must cross the countryside to deliver products over long distances; therefore, the pipeline has many neighbours. The pipeline crosses under creeks and rivers, highways and roads, farmers’ fields, parks, and may be close to homes or businesses.

Figure 1 — “Right of way”

Written agreements or easements, between landowners and pipeline companies allow pipeline companies to construct and maintain pipeline right of way (ROW) across private property. Most pipelines are buried below ground in a ROW. The working space needed during initial construction may be temporarily wider but the permanent ROW width varies depending on the easement, the pipeline system, the presence of other nearby utilities and the land use along the ROW Many of the ROWs are 50 feet wide, but may be wider or narrower in specific locations. These ROWs are in place for the following reasons:

• Enables workers to gain access for inspection, maintenance, testing or emergencies

• Maintains an unobstructed view for frequent aerial surveillance

• Identifies an area that restricts certain activities to protect the landowner and the community through which the pipeline passes and the pipeline itself.



While permanent pipeline markers are located at roads, railways and other intervals along the ROW, these show only the approximate location of the buried pipelines. The depth and location of the pipelines vary within the ROW. The ROW exists in many kinds of terrain from river crossings and cultivated fields to urban areas. Because of this, there is no distinct look to the ROW.

Environmental considerationsEnvironmental damage can be a huge concern, not only when installing the pipeline but also when constructing the ROW. General pipeline labourers perform many tasks and take many measures to help mitigate these potential problems.

Silt fencesSilt fences are synthetic, fabric fences that are used to control erosion and sediment in run-off water. A ditch is dug, stakes are installed and the fabric fence secured to the stakes. The ditch is back-filled, securing the fabric to the ground. The water slowly passes through the fence while holding any sediment back. These protective barriers are installed to:

• Help control site erosion

• Filter out sediment from drainage leading to natural waterways, such as rivers, streams, and lakes

• Help prevent hazardous substances like fuel and hydraulic oil from washing into ditches or other natural drainage areas.

Silt fences, as well as other erosion control devices, are left in place for long periods of time. In some cases, silt fences will be removed during the clean-up process. Other times they are left in place for one to two growing seasons or until vegetation grows back to stabilize the soil and eliminate the need for erosion control. Every situation is different, the silt fence is either pulled up and disposed of or rolled up for re-use.

Figure 2 — Silt fence



Hay balesHay bales provide another type of erosion control. A hay bale erosion control system consists of a continuous line of hay bales, placed end to end, that are held in place by driving stakes through the bales into the ground. Hay bales can be used by themselves or in combination with fabric silt fences by placing the bales directly behind the fencing.

Figure 3 — Hay bale berm

Silt socksSilt socks, also called core logs, are made of a synthetic fabric in the shape of a tube. They are filled with wood chips and composite materials. Silt socks work in a manner similar to silt fences and hay bales, but in pre-made tubes. Rock socks are similar to silt socks in that they filter out debris, silt and organics before the water makes its way off-site or into a waterway, but rock socks are placed directly into catch basins and lawn basins.

Figure 4 — Silt socks



Water barsWater bars are permanent ridges and/or channels used in sloping areas to flow down erosive run-off water. Water bars channel the run-off water to the side of the area so it does no accumulate and cause more substantial erosion. Water bars are often used on temporary dirt roads to minimize wash outs.

Rock filter outletsRock filter outlets are used in areas of concentrated water flow to help filter sediment out of the run-off water. Clean rock is placed in the path of the water flow and as the water passes through the rock, the sediment is left in the rock and the water runs out. This is a popular application in cut-off ditches to help filter water. Another common method of discharging water is with the use of a filter bag. A filter bag is a large collapsible bag that has small holes in it. It works the same way that rock filter outlets do in that they filter the sediment out of the water and they discharge the water slowly.

Figure 5 — Rock filter outlet

Mud matsMud mats are laid on the ground to allow equipment to drive over an area without getting bogged down in the mud. This helps to keep mud and dirt from migrating to other areas where it could cause issues or contaminate waterways. Mud mats are made wood timbers that are bound together. The equipment uses lifting straps or cables of sufficient strength that are attached to the mats to move the mats around as they move. It is very important to rig and lift mud mats properly to avoid accidents.

At some point in the project, the ROW will meet roadways and waterways. These inhibitors need to be crossed or dealt with using different methods depending on their size and purpose. This work is usually done by the grading crew. The grading crew is brought in after the ROW has been marked and any clearing has been done, and they are responsible for moving large amounts of dirt, installing temporary bridges, bringing in additional materials, and generally shaping the terrain for what is needed ahead.



Crossing roadways can cause a lot of extra work. Not only for the digging of the pipeline but also for the manoeuvring of any equipment and materials that need to be used. If the roadway is a smaller, more rural road, sometimes they can be blocked as long as the right traffic control measures have been put into place. If this is possible that is the best case scenario because it causes little alteration and is the cheapest alternative. If the road is a major route and cannot be blocked, that can cause extra work. Crews and equipment will have to be hauled around them or a crossing may have to be built over the roadway. With regards to digging the pipeline itself, if many existing utilities are in the way or the roadway cannot be crossed, the pipeline may have to be bored underneath.

Crossing waterways has its own set of challenges pertaining to the equipment and materials as well. In the case of very large waterways, which may or may not contain heavy boat traffic, equipment and materials may have to track back to the nearest road, loaded on low-beds, and hauled around to the next road so work can continue on the other side. With some medium-sized waterways, such as irrigation canals or creeks, a small temporary bridge can sometimes be built using railroad cars, mats or several large culverts. With very small waterways, sometimes equipment and materials can be utilised right through the waterway as long as the proper environmental measures have been taken.

Directional drillingWhen crossing under a waterway with the pipeline, the minimum cover is 4' (1.2 m). Most crossings at rivers, roads, and other obstructions are done using directional drilling equipment. A directional drill is a specialty machine that drills pipes under rivers, roads and other obstructions. It works by boring a hole under a roadway, and while it drills underneath, it drags a pipe or casing along with it until it reaches the other side. Now the pipes or pipe casings have completed crossed underneath the roadway or waterway.

Figure 6 — Directional drilling



Other than crossing a waterway or roadway, they are a few other situations in the environment that can dictate specific control measures that need to take place. Here are a few of those measures:

• When crossing a roadway with heavy equipment, old tires are often used to protect the asphalt and the concrete curbs. Labourers will place the old tires close together along where the equipment tracks are going across so the equipment can walk on top of the tires.

• When crossing a muskeg or a bog, it must be crossed when it is frozen otherwise equipment and materials will sink.

• When coming within proximity of overhead power lines, goal posts must be set up to help mark those lines.

• When crossing roadways with existing utilities, equipment can only get within certain specifications before the utility has to be located by hand.

• At times, access roads need to be built for equipment and vehicle travel. These access roads need to be built carefully and with the surrounding environment in mind. If the access road is being used just during the construction phase, the land needs to be restored to its original condition once construction is done.

• Sometimes plugs need to be placed across a ditch line in agricultural areas for landowners to cross over the ditch. Hard plugs are undisturbed ground left in place. Soft plugs are excavated land that has been put back into place and compacted.

HazardsAlthough no pipeline is necessarily being constructed when constructing the R.O.W, there are still a number of potential hazards. Workers must be aware of their work environment and conditions in order to identify hazards. Once identified, hazards can be reduced or eliminated to protect the workers.

Heavy snowfalls, sleet, rain, lightning, high winds, fog and other severe weather conditions that can pose serious hazards on the worksite. Weather extremes can affect soil conditions, visibility, walking and working surfaces or cause flash floods or mudslides. When possible, workers should try to assess weather conditions as they work, be prepared to adapt for weather change, wear appropriate clothing and gear, and avoid working outside during storms or other extreme weather conditions.

Many times, pipeline workers don’t have an option as to whether they work in the heat or the cold. When working in these conditions, workers need to be aware of heat and cold stress. Heat stress can cause nausea, dehydration, exhaustion and sun stroke. Physical exertion and humidity will accelerate the rate and effects of heat stress. Exposure to extreme cold can lead to frostbite, chills, and numb extremities.



Both heat and cold stress hazards can reduce dexterity, work capacity and mental alertness. Controls include:

• Appropriate clothing, sun screen or blocks for heat stress and UV radiation

• Adequate breaks and fluids to assist with heat stress

• Layered clothing and frequent breaks during cold conditions

Working outdoors, pipeline workers are exposed to a wide variety of biological hazards such as:

• Microorganisms (bacteria, fungi, viruses)

• Parasites (roundworms, tapeworms)

• Plants (poison ivy, nettles, tree pollen)

• Insects (mosquitoes, spiders, wasps)

Certain plants can cause dermatitis, allergies, and eye irritation. Insect bites and stings can cause hives, blisters, rashes and allergic reactions in sensitized individuals. Plants and insects can also be carriers for other infectious diseases along with causing pain and discomfort.

Animals can also be an evident hazard on rural pipelines. Both wild and tame animals can be hazardous since the urine, feces, saliva, hair, dander, blood and feathers of animals can cause allergic reactions or carry infectious diseases. Exposure can be through direct contact, bites, scratches or inhalation. Diseases can range from asthma, rashes, allergies and rabies.

Both carnivores (fox, coyotes, wolves, bears) and herbivores (deer, elk, moose) can pose a physical threat to workers. Awareness and avoidance of larger animals is a primary control measure. Animal repellents and air horns can be effective deterrents.

Along with these hazards there are endless others that can cause harm on a pipeline ROW. Whether it’s when using chemicals, potential strain injuries, pinch points, proximity to falling trees, moving equipment, vehicle emissions or visibility issues, workers need to stay aware at all times.

Governmental regulationsContractors must comply with federal regulations as well as their own company’s specific health and safety policies and programs. Complying with these programs requires contractors to:

• Submit all documentation for review of pipeline personnel at the worksite including permits, licenses, contract documents, and contractor safety approved stickers and/or waivers.

• Hold periodic briefings on site to review guidelines or conditions related to safety.

• Ensure that no equipment or vehicle enters the ROW unless a permit has been granted.



• Ensure no work occurs within 8 m (25') of the centreline of the nearest pipeline unless in the presence of assigned pipeline personnel.

• Ensure no vehicle or heavy equipment is closer than 5 m (16') of nearest pipeline unless assigned pipeline personnel are present or an exemption is authorized.

• Whenever trains pass, workers must be no closer than 5m (16’) from any switch stand and if possible be on the opposite side of the pipe.

• Check the location of power and communication cables buried in ROWs before any excavation, driving stakes or other ground work is done.

• Ensure that pipeline equipment is only operated by qualified personnel.

For the safety and security of everyone involved on pipeline worksites, a number of prohibitions are established and maintained. A few of those further restrictions are:

• No explosives are permitted without company approval.

• Smoking is not permitted in any company workplace or vehicle.

• Drugs and alcohol are not permitted.

• Horseplay, practical jokes and fighting are not permitted.

If any of the restrictions are not followed, the contractor will be notified and swiftly investigated. Violation could lead to expulsion from the worksite.

Job-site specific rules Just like with any trade, pipeline tasks can change daily or even hourly. Each task has its own set of challenges and hazards that need to be mitigated. This requires workers, crew foremen and superintendents to be on the same page. Workers must be briefed to know what tasks they will perform, how to work as a team, and how to do these tasks safely. To help achieve these objectives, daily briefings or toolbox talks have become a very commonplace procedure.

Figure 7 — Blasting crew prepare site



An effective toolbox talk not only provides information and direction to the workers, but it also allows workers to ask questions and bring up some issues that they are seeing out on the job. This ensures that workers can get a full understanding of all the aspects of the job tasks and the safe work procedures that are involved. Some of the other major benefits of engaging in these talks are improved communication, tasks efficiency and coordination, the workers right to know of the hazards and it improves the overall health and safety of everyone on site.

Each contractor has their own format and method of performing a job briefing. Although topics may vary slightly between companies, some of the topics that should be covered throughout are:

• Work schedule

• Chain of command

• Exit strategy/plan

• Emergency plan including identifying the emergency personnel

• Any unusual conditions

• Any unusual tasks

Each contractor may differ, but there are general rules that relate to all pipeline job sites:

• All materials should be stored properly or locked up if necessary when not in use.

• All walkways and paths must be kept clear of material, equipment and debris.

• Spills of oil, grease, hydraulic fluid and related materials must be cleaned immediately using the proper procedures.

• Wear any appropriate PPE necessary for any task.

• When possible, steer clear of pipes and be alert and aware of your surroundings.

• When required to cross a pipe, look both ways for trains or equipment, walk straight across when safe and never less than 8 m (25') from any equipment.

Clearing brushThe clearing crew is the crew that is tasked with clearing any brush that is inside of the ROW. Clearing a ROW consists of removing all above ground obstructions from the work area. This involves cutting down trees and the removal of timber and brush. On some projects, the timber and brush debris will need to be burned on site. After the trees are dropped, all of their limbs are trimmed off. The logs are then dragged to the side of the ROW by a skidder or other heavy equipment. As a labourer on a pipeline clearing crew you may be tasked with operating chainsaws, cutting and burning of trees and brush, performing fire watches, or hooking up all equipment cables and chains.



Figure 8 — Falling a tree

If you have been trained to use a chainsaw safely, you may do the cutting and be known as a hard cutter or tree feller. Hard cutters drop trees and work with the cutting dozer. Often times, the contractor may hire specialized workers to do the tree cutting. The most important factor is to watch out for co-workers and others safety when dropping trees and to try to keep a safe distance. This should be done in a controlled area where it is important to be alert and aware of all workers and visitors at all times. Verbal and nonverbal signals must be used and understood by all members within the control zone. Also, when around heavy equipment, the operator should only be assisted when he is aware of your presence and has asked for help.

The cleared brush may be fed into a brush chipper. Brush chippers come in many sizes with the larger ones having hydraulic arms to feed entire trees into the chipper. The most common types of chippers require manual feeding. They are an effective way to dispose of brush but can be extremely dangerous when not used correctly. The chipper has powerful feeder rollers that forcefully pull the trees and branches into the chipper. If entangled with the brush, there’s a risk of being pulled into the chipper along with it. Some of the safety procedures include the following:

• Read and observe all safety warnings posed on the machine.

• Read the operator’s manual before using it.

• Do not wear any loose clothing, including loose gloves, shirts or pants.

• Know where all of the panic bars are at all times.

• Move away from the chipper after placing wood into the opening.

• Have another worker nearby as a precaution.

• Maintain secure footing.



Figure 9 — Brush chipper

In some cases, the brush can be burned. All controlled burning must be supervised and performed in strict accordance with all permits and specifications. Before burning starts, conditions such as the time, wind, moisture and surrounding structures need to be evaluated.

Clearance markers and signageAll pipeline work must be done within the ROW boundaries. This includes all activities, even ones as small as eating lunch and turning a vehicle around. In addition, all environmental rules regulations must be followed within the boundaries. All staking and flagging that is used to mark out existing utilities or power lines must be paid attention to. Exclusion areas or special work zones such as wildlife habitats or archaeological sites need to be avoided. Survey crews will usually mark these areas sensitive areas out so that the clearing crew is very aware of them.

Usually, other workers flag the ROW ahead of the hard cutters; however, labourers are usually responsible for maintaining the staking and flagging as the work progresses. A labourer would need to become familiar with the different types of temporary and permanent markers and how to recognize the ROW boundaries and the ditch line. They should know the off-set distances, stake frequency, flagging colours, and marking customs to accurately install, replace and measure from these important markings.



The amount of ROW that is needed is going to vary based on the environmental conditions and requirements by land owners and environmentalists. In many cases, a new pipeline will be laid parallel to an old line. This reduces work because the ROW has already been cut. When clearing for a new ROW the labourer doing the flagging must pay attention to the markings on all stakes in the ditch line.

Figure 10 — Clearance markers

After the grade crew is finished smoothing out the R.O.W, the ditch line is staked. These markers indicate the depth of the ditch as well as the centerline. The ditch crew follows these stakes to excavate the ditch. Ditch stakes are set by surveyors and are marked to indicate changes in the depth and direction of the ditch. As a pipeline labourer on the ditch crew, be aware of all markers and know their meanings as they are responsible for setting and maintaining the off-set stakes. Off-set stakes are stakes set at a pre-determined distance away from the ditch stakes to indicate the ditch’s location after the ditch stakes have been removed. As the ditch excavation proceeds, measurements are taken from the off-set stakes to keep the ditch in the proper location. An important role of the pipeline labourer is to take measurements from these off-set stakes periodically and to signal the operators to make adjustments as needed. This helps to keep the ditch in the proper location.

Pipeline installationOnce the grade crew has come through and readied the R.O.W, the other pipeline crews can start to do their work. In this unit, various crews will be discussed as well as various pipeline applications that need to take place to ensure a properly installed pipeline.



The ditch crewThe ditch crew is made up of equipment operators and the people who assist them, including the labourers. The ditch crew’s main purpose is to excavate the ditches to the correct depth and width to provide a firm, continuous support for the pipeline to rest on.

The term ditch is the same as the term trench and vice versa. The depth and width of the ditch depends on the size of the pipe and the job specifications. The ditch is usually dug to one side of the R.O.W rather than in the centre. This allows room for equipment to move along the ROW and space for some materials to be stockpiled. It also provides space for future installations. The ditch line is the exact location that a pipe will run from start to finish.

The width of the ditch and the depth of cover at a particular location will be described in the specifications or listed on an alignment sheet. The typical width of the pipeline ditch ranges from as small as 14" for smaller diameter to much larger ditches for larger diameter piping. The ditch depth is also affected by required clearances when crossing existing utilities or other pipelines. The minimum cover will vary but it cannot be any lower than 3 ft.

Figure 11 — Width of the ditch



When digging trenches, safety is a must. Recognizing soil types and stability while using the proper protective systems can minimize the risks. To help determine the soil type, several test holes are dug and inspected. Be aware that test holes may not reflect all soil types in the area, nor do they locate all pre-existing excavations.

Figure 12 — Dredge

As a CCW working on a ditch crew, one of your main duties will be to assist the operators. You can do this by watching for and helping avoid underground and overhead obstructions, performing minor maintenance on equipment, staying constantly aware of the ROW boundaries and keeping soil within them, and removing loose rocks and clods of soil from the bottom and sides of ditches.

Each ditch varies and so do some of the circumstances behind how they should be dug. Due to this fact, there are several pieces of equipment that can be used to dig ditches.

A ditching machine (wheel ditcher) is used in areas with stable soil and few underground obstructions.

• A track-hoe (excavator) is the most commonly used due to its versatility and array of sizes and power.

• Hydraulic backhoes are used in areas not practical for wheel ditchers or track-hoes.

• A bulldozer with a ripper attachment is sometimes used to break up rock along a ditch line and to detect areas that may need blasting.



Skid crewThe primary job of the skid crew is to place enough skids on the ROW to support the pipe that will be delivered by the pipe stringing crew later on. A skid is a piece of wood that is 4" thick, 6" wide and 4' long. One skid is placed on each side of the pipe and chocked with another at each end to prevent the pipe from rolling off. It is very important to keep the pipe supported and off of the ground for a variety of reasons:

• To keep the ends of the pipe positioned so that the bevels can be buffed all the way around the pipe.

• To keep the pipe coating from being damaged.

• To allow for easy pipe hooking and pipe seam rolling.

• To allow room for welding to be done on the bottom of the pipe.

Figure 13 — Skid-supported pipe

Skids are dropped off at a set distance from the ditch line and from each other. They are placed to match the length of pipe joints, which will change. They are also placed to leave room for the ditching crew as the stringing crew will catch up to and pass by the ditch crew. It is best to know the length of the pipe and how far from the ditch to string out the skids to best help the crews afterward. Then the skids will not be in the way of future work or too far from where they are needed.

Stringing crewThe pipe stringing crew positions the pipe in place along the ditch line. The piece of equipment most often used for stringing pipe is known as a stringing side boom. The boom must be properly attached (as it is detached during transport), all cables must be inspected and placed



in the block pulleys and be neatly wrapped around the load cable drums, and the pipe hooks attached to the cable ends. Hooks have an eye welded onto them on which to tie a tag line. Although the use of a side boom is a common method of positioning pipe, it is not the only method used today. A second method uses a backhoe with an attached hydraulic suction cup device. The backhoe lifts the pipe and places it in position.

Along with cables, web slings and chains are often used for different rigging purposes. Chains cannot be in any direct contact with the pipe as it will mar and scratch the coating. Synthetic web slings if strong enough are the best choice to use as a rigging material.

Bending crewAt times the pipe needs to be bent to meet the ditch line and the ROW. The pipe is bent using a bending machine and the bending machine is pulled to an area where there is room to work. The pipe is bent following this procedure:

1. The engineer marks the pipe where it is to be bent.

2. A side boom is hooked at the marked joint with a choker-belt.

3. The marked joint is hooked on the centre line and fed into the bending machine.

4. If the pipe has a small 2–4% bend, it will only require a 2 or 3 stage bend. That means that it is marked and bent in 2–3 different places approx. 1 ft. apart.

5. The pipe is pulled in by the feed line of the machine until the first mark is in the bending area.

6. The machine operator pulls the ending shoe lever to cause the hydraulic system to put pressure on the shoes. As the pressure pushes the bottom shoes upward, the pipe bends.

7. Once the bend is made, the foreman or engineer takes a quick degree angle check on the bend. If more bend is needed, another bend is performed.

Pipe can only be bent at a certain percentage. If large bends are necessary, tube turns are placed which are pre-fabricated pipe fittings. With large diameter pipe there is also a risk that during the bending process it could take on an oval shape. To prevent this, a device called a mandrel is placed inside the pipe and pneumatically operated from the outside, to receive the force during the bending procedure.

Welding crewA welding crew consists of the welders themselves and welder’s helpers which are the CCWs. A welding crew is essentially a moving welding assembly line because it moves to where all the pipes have been strung out.



First the CCWs go to ends of the pipe and clean them with grinding discs and wire wheels to prep them for the weld. Once the ends are prepped and ready for the welding process to begin, the 2 pipes being welded are brought together. It is important to note that each length of pipe has a lengthwise weld on it as well. Due to this fact, when the two pipes are welded together it is important that those lengthwise welds do not line up to help with the structural integrity of the joint.

Figure 14 — Pipe welding

Now that all the prepping measures have been put in place, the welders can begin. Each weld is performed by a series of passes. After each pass the welder’s helpers need to re-clean and grind the joint to get it ready for the next pass.

After the weld has been completed, it needs to be inspected. This is usually done using a device that inspects the joint using an x-ray.

The majority of the time, the welding will be done outside of the ditch. It makes it easier to maneuver the pipe, gives the workers more space to work, and the pipe has already been strung outside of the ditch. The only time that welding needs to be done in the ditch is at any tie-in points.

The entire welding process can be quite a dangerous procedure. Here are a few of the hazards that need to be controlled are:

• Airborne particles from grinding the pipe ends

• UV rays during the welding

• Radiation exposure during the x-ray inspection

• Moving pieces of equipment, suspended pipe and various pinch points



Coating crewThe main function of pipe coatings is to protect the steel pipe from coming into contact with water. Protection against water is important because moisture in the coating can carry electrical current through the coating material and onto the pipe, which will start the corrosion process. Cathodic protection is also used as an anti-corrosion method for protecting steel pipe.

The coating crew has two main responsibilities:

• Coat the bare pipe at the weld – The pipe is already coated when transported onto the site except for approx. 6"–12" at each end. This is so the weld can take place without burning the coating in the process. After the ends are welded together, the coating crew cleans the area and then applies a coating as described in job specifications.

• Complete patch work on the pipe coating – The coating crew inspects the pre-coated areas of the pipe for any defects by using a device that identifies imperfections in the coating that cannot be seen and then patches any areas that are found. This process is called jeeping.

JeepingA jeep is a portable electric metal locator. The jeep identifies any bare spots in the pre-coated pipe, makes a beeping sound, and sends an electrical arc on the spot. The jeep uses a battery-powered static charge to detect any abnormality in the pipe coating. The jeep has a circular coil that goes around the pipe and hooks up to the locator. At the end of the jeep is a metal tail that drags on the ground that works as a ground connection.

The jeep detector is an efficient method for finding bare spots on the pipe. Visual inspections are not reliable because it is difficult to spot cracked coating or pin holes, especially on the bottom of the pipe.

There are many types of pipe coatings. In most cases, the coating used on the welds is the same type of coating used on the pipe. However, sometimes they are different. For example, if the pipe has an epoxy coating on it, it may need shrink-sleeves on the welds at one location but epoxy coating at another location. The type of coating used depends on the job specifications.

Before a coating can be applied, the most important task is cleaning and priming the pipe. The primer can be applied with a paint brush and it acts as a bonding agent. The two most common methods of cleaning a pipe are by buffing or grinding with a wire brush, or sandblasting. Many pipe coatings including blasting sand and primers contain very hazardous substances. One should always protect themselves from contamination.



Each pipeline is going to be different and may call for different coatings. Here are a few of the most common types:

• Somastic• Shrink sleeve• Epoxy

Somastic coatingSomastic coating is used mainly on concrete-coated pipe. Concrete-coated pipe is sometimes used in very wet, marshy areas for added weight. Some somastic coating is available in a pre-mix solid state. The coating has been heated, mixed with sand, and poured in forms to cool. Once cooled, the coating is put on pallets and transported to the job site. However, most somastic coating has to be melted and poured into forms built around the pipe welds.

Shrink sleevesA shrink sleeve is a piece of poly-type coating placed around a pipe that shrinks and bonds to the pipe when heat is applied. A shrink sleeve is a very good method of coating pipe. Sometimes these coatings are called heat-shrink sleeves because heat is used to shrink the sleeves around the pipe.

Figure 15 — Shrink sleeve



Epoxy coatingThe most frequently used coating today is an epoxy coating. It is easily applied and uses quick patching techniques. Epoxy comes in 3 forms; powder, stick, and 2-part paint mix.

Powder epoxy is applied by a device that looks like a shop-vac. The weld must be heated to a certain temperature. This is done by using heating coils powered from a large generator. The coils are wrapped around a circular device that opens up to surround the pipe.

Stick epoxy is used for patching the bad spots in the coating that the jeep has located. The stick is applied by heating it with a hand torch and then smearing it once the epoxy has melted.

2-Part paint mix is used on the final welds done at the tie-ins, valves, tube turns, and long repair work on the coating. When using a 2-part paint epoxy, you mix one epoxy substance with another to get a thick compound. This compound can be painted on the pipe.

Lowering-in processThe lowering-in of the pipeline consists of lowering down large welded sections of the pipe into the ditch using side booms. The process is done this way by having the fleet of side booms (usually 3 or more) walk towards the ditch with the pipe suspended either using lowering belts or cradles. A cradle fits around a pipe and has a hooking eye on top which attaches to the side boom. The inside of the cradle has rubber padded rollers on the sides and rubber wheels on the bottom where the weight of the pipe rests. The rollers and the wheel roll with the movement of the side boom. A cradle is optimal to use over using lowering belts, but sometimes belts are used because the weight of the pipeline in addition to the cradle is too much for the side booms to handle.

Figure 16 — Lowering in process



Before the pipe can actually be lowered-in, a few things need to be achieved. First off, all stones or debris need to be removed from the ditch to ensure that they won’t damage the coating. This can be done by a machine, usually with a clamshell as well as by hand, but this can also be done by placing sufficient padding on the bottom of the trench. The most common types of padding material are with dirt or fine gravels, earth-filled sacks (sandbags), or with some synthetic materials. Along with having padding, the trench must also be vacated of any standing water. This can be done by using water pumps.

Once the trench is ready, one last jeep is done on the pipe to ensure that the coating is not damaged before it is lowered-in. If the coating is sufficient, then the side booms start to navigate towards the ditch in unison. Once they are close enough to the ditch’s edge, the first side boom extends his boom until it is over where the pipe needs to be laid, which is when he then starts to lower the pipe in. While this is happening, the crew needs to make sure that the pipe does not make any contact with the trench as that may damage the coating. Once the pipe is down and there is some slack in the line, that boom then unhooks and leapfrogs past the last side-boom. The process just repeats itself this way with boom #2 now being at the end.

Figure 17 — Pipe in position

As a CCW on the lowering crew, there are a few things that you will specifically need to emphasize. The key is signaling and monitoring. There will be suspended pipe in the air, a lot of different workers moving around and multiple side booms in operation so maintaining good communication is important for maintaining safety and efficiency. As the work progresses, skids will constantly need to be moved out of the way because the pipeline is now moving into the ditch and side booms are going to be migrating further and further up the ditch line.

After the long welded section of pipe has been completely lowered into the ditch, the tie-ins will need to be done. The tie-in welds are the last welds performed on the line. Tie-in sections are those sections of pipe that need to be welded in the ditch to fill in the gaps left in the main line due to an obstacle. Obstacles that usually need to be filled in include roads, railroads, waterways, utility crossings, buildings, airstrips, etc.



BackfillingOnce the pipeline has been lowered into the ditch, backfilling can start. Each pipeline will have different specifications but here is a general overview of what is needed to be done. First the pipe needs to be protected so that the coating isn’t damaged during the backfilling and compacting process. This is done either with a specified soil or gravel, or with the use of rock-shielding. Rock-shielding is a sheet of strong plastic or roofing felt that covers the pipes while back-filling.

Once the pipe has been protected, the backfilling of the entire trench can commence. This is done with the use of road graders and dozers. While the graders and dozers are pushing material a CCW needs to work closely with the equipment. Here the CCW performs the following tasks:

• Opens and closes gaps (fencing)

• Keeps rocks from hitting the pipe by directing the back-fill dozer around the rock.

• Deflects rock to the sides of the ditch with a shovel.

• Assists dozer operators when they need to change the angle and pitch of the dozer blades.

Along with rock shields, buckets with grills are used to prevent large rock from damaging the coating on the initial fill.

Figure 18 — Bucket with grill

After the ditch has been backfilled, it will need to be compacted. Based on the job specifications, the ditch will need to be backfilled in lifts. As it is backfilled in lifts evenly on either side of the pipe, it will also need to be compacted evenly on either side of the pipe as well. If you completely compact one side of the pipeline before starting to do the other, it could cause the pipeline to shift so it is better to try to stagger the operation.



COMPETENCY I3

Perform Pipeline Maintenance

Pipeline testingTesting the pipe consists of pressurizing the line with water to a required pressure, and maintaining that pressure for a specified period of time. This method of hydrostatic testing is done to check for leaks or weak spots before the pipeline is put into service. The crew is made up of one or more workers from different crafts who work together to set up the testing equipment.

The testing is done in loops. A loop can be the distance from one in-line valve to another. In most cases, loops are tested one a time. If there is a leak in the short loop in the line, this method of testing makes locating the leak easier. On a small-scale job, the entire line usually is tested at once. The length of the test loop can vary from less than a km to hundreds of kms.

A water supply is necessary for testing. If the water supply is nearby, then setting up the pump is easier. However, it is not always possible to set up the main water testing pump near a source of water. When this is the case, the testing crew must run a small, temporary water line between the water supply and the water pump. The sections of pipe for this job are wash-pipe or field joints. Field joints are connected by rubber gasket collars.

Once testing has started it must continue non-stop until the testing time has ended. The job specifications indicate the testing time requirements. Instruments called pressure recorders monitor the pressure during the test period. Since both the ambient and external temperatures have an effect on the test pressure, temperature recorders are also used. If the required test pressure is maintained within the specified range for the proper period of time, then the test is certified and accepted. If a change in test pressure cannot be justified by corresponding data, such as temperature fluctuation, then the test pressure is maintained until the results are satisfactory or until the source of the problem can be found and repaired.

Once the test is accepted, pressure is relieved by opening the valves on the test manifold and reducing the pressure. Then, either compressed air supplied by the contractor or gas supplied by the owner is used to propel the pig back through the pipeline, thereby removing all the water in the section. After the water is removed, several additional pig runs may be required to dry the pipeline thoroughly. After the line is cleaned and dried, the test section is tied back into the adjacent pipeline section. These are the last two welds needed to put the line under service. It may be a requirement to retest the welds under pressure, however, most of the time it is enough for the welds to pass the x-ray requirements. At this point, the line is ready for service. Pressure tests have to be certified before the pipeline can be put into service.



Locating and exposing defective areasTo operate a pipeline safely and efficiently, operators have to coordinate many different functions in multiple remote locations. To achieve this effectively, modern pipelines are managed through the use of a Supervisory Control and Data Acquisition (SCADA) systems. A SCADA system collects data from multiple locations, displays it to operators and allows the operators to remotely control the operations of the pipeline.

A multitude of sensors are installed at many points along the pipeline. Pressure and flow sensors, along with other information is collected and transmitted to the central command center at the SCADA headquarters. Specially trained operators monitor all this data and control the operation of the pipeline. Information on pressure, flow rates, pump operation, product flow, product separations, maintenance cycles, inputs into the pipeline, outputs from the pipeline, volume calculations and much more is all collected and fed into specialized computer software designed to manage that specific pipeline. Operating conditions are compared to safety parameters and kept within strict limits. Maintenance as well as emergency response actions can be taken from the command center.

In general, Smart Pigs are used to detect stress corrosion cracking, general and pitting corrosion. These objects are equipped with highly tuned sensors that can gauge the thickness of the pipes they are traveling through along with cracks, fissures, erosion and other problems that may affect the integrity of the pipeline. Data is collected and transmitted to a team that interprets that data to gauge the health of the pipeline segments being scanned. If any problems are found then teams not only know what the problem is thanks to a heavy set of data points, but know exactly where to go to replace the affected pipe thanks to highly tuned sensors.

Figure 1 — Smart pig



Once an area for repair has been found, it is now up to the crew to locate that area and expose the pipeline for repair.

Before beginning any excavation, available sources of information should be checked to determine if there are existing utility lines in the area and exactly where the pipeline is located. Call BC One Call, check drawings, as-builts, paint marks on the ground, tracer tape, etc. An M-scope operator and a surveyor use the project plans, the M-scope, and the surveying/pigging data to locate the buried pipeline for repair as well as any adjacent utilities.

DiggingThe best way to locate existing utility lines is to use a non-destructive method, like a hydro-vac. A hydro-vac is a truck-mounted machine that combines the use of a high-pressure water nozzle with a large vacuum suction hose. Using a hydro-vac for potholing can be extremely effective for some applications. A hydro-vac is a good choice when the soil is difficult to dig, the digging must be done in a small area, or the utilities being potholed are fragile or considered critical.

Using a hydro-vac is great for locating exactly where the pipeline is, but once the pipeline and any nearby utilities have been found, then a backhoe or track hoe will most likely be used to dig up the defective area. To perform a repair, workers will need the entire pipe to be exposed all the way around and ample area is needed in order to do the repair properly. This involves an operator digging down below the bottom of the pipe on both sides of the pipe, but a safe distance from the pipe. The operator can strip the bulk of the material from beside the pipe but CCWs will need to expose the rest of the pipe using shovels.

When working with operators, CCWs play an important role in assisting equipment operators in working efficiently and avoiding mishaps. When working with heavy equipment, it is important to follow safety and operational procedures. Some things to note are:

• Know and use clear hand signals to communicate with the operator.

• Keep an eye out for obstacles, obstructions, and other hazards that the operator needs to be aware of.

• Always keep an eye on the digging to watch for existing trench lines or other indicators that utilities may be buried in the area.

• Do not stand behind the machine or in the operator’s blind spots.

Once the pipeline repair area has been exposed, before a worker can enter, the excavation needs to be safe. When working in trenches, it is critical to consider the danger of cave-ins and use appropriate cave-in protection methods to protect all workers. In general, there are three main protective systems used to guard against cave-ins. They are sloping and benching, shoring, and shielding.



Each situation is going to be different and which protection method you use will depend on various factors like; the depth of the excavation, the type of soil, the width of the excavation, whether proper sloping can take place, etc. A worker should never work in any excavation over 1.2 m in depth without some sort of protective system. Assume all soils are unstable unless they are determined to be otherwise.

To provide workers with readily available trench access for excavations that are more than 4' deep, there must be ladders, ramps, steps, or other safe means of access both into and out of the trench. These must be kept within 25' of all workers at all times.

Figure 2 — Pipeline repair

After the repaired area has been dug up and exposed, it needs to jeeped or x-rayed to find the exact location of the deficiency. Jeeping or holiday detecting identifies any bare spots in the pre-coated pipe making a beeping sound and sending an electrical arc on the spot. Methods of weld testing and analysis are used to assure the quality and correctness of the weld after it is completed. This term generally refers to testing and analysis focused on the quality and strength of the weld, but may refer to technological actions to check for the presence, position and extent of welds.

All types of pipe coating, including factory or field applied, must be free of damages and defects. Any break in the pipeline coating, no matter how small, can cause the pipe to corrode within months of installation and possibly leak. Leaks could create environmental problems, depending on what the pipe is carrying. To prevent leaks, the pipe coating is tested with a



device called a holiday detector. This is an efficient method for finding spots on the pipe that are not completely coated. Visual inspections are not reliable because it is difficult to spot cracked coating or pinholes, especially at the bottom of the pipe. Locating the holiday once the defective area has been located is a very important task.

Removing existing coatingIf it is only a repair of the coating that is needed (a minor repair), the existing coating in and around the area will need to be removed and the pipe will need to be clean in order to place a new coating. This can be performed in a variety of ways and some ways may be better than others based on what equipment is available, what type of coating is being placed, etc.

Whenever a pipe is exposed, for any reason, it is required that the coating of the pipe be inspected. When a pipe is exposed, it presents a valuable opportunity to visually inspect the exterior of the pipe and the applied coating. Many operators require workers to pass standardized tests before being considered qualified to perform certain tasks. When inspecting the coating on an existing pipeline, there are a few different defects to look for including; soil stress, cracks in the coating, disbonded coating, moisture under the coating, or lack of coating. If you see one of these indicators, there may be an issue that needs to be addressed, and a new coating may need to be applied.

The coatings need a clean surface in order to adhere to the pipe. Most corrosion on the pipeline occurs at the girth weld where field applied coatings are subject to quality problems, due in part to the level of quality of the surface preparation. Surface preparation includes cleaning the pipe and priming the area, if needed. Most coatings do not need a primer, however, a small number of tapes do. If there is any great or oil on the pipe, it may need to be cleaned off with a solvent cleaner first. Cleaning methods vary depending on the application method and the situation (age and condition of the pipe, coating girth weld, patching parent coatings, etc.).



Typical cleaning methods include the following:

• Sandblasting

• Buffing or grinding with a wire brush attachment on a power grinder

• Buffing or grinding by hand using a wire brush or sandpaper

• High-pressure water washing/blasting

Buffing and grinding with hand and/or power tools is typically done when working with smaller pipe, or when repairing existing lines. Water washing or water blasting is done in a very similar way to sandblasting. A high-pressure water hose, spraying a jet of water at 3000–7000 psi, is used like the sand hose. Water blasting is used more commonly on existing pipe, above ground pipe in particular. It works basically the same as a commercial power washer. The advantage to using water is that there is no sand or slag to clean up afterward.

Sandblasting, however, is the most common cleaning method used on the pipeline. On this crew, you will need to know how to use the sandblaster, how to clear clogs, and how to perform basic maintenance on the equipment.

No matter what equipment you are using to remove the existing coating, be aware of your surroundings and make sure to use every tool properly.

Pup/sleeve setupIf the pipe has a deficiency that is deeper than the coating and compromises the structural integrity of the pipeline, then a section may need to be cut out of the existing pipeline and replaced with a new piece. This is often called a pup. When performing this task it will usually take place by a specialized crew and many measures will need to be taken so that the situation is safe to do so. The pipeline needs to be completely de-energized. This can be quite costly and time consuming and that is why this is only performed if it is necessary to do so.

When inspecting an exposed pipe for structural integrity, look for any of the following problems:

• Dents

• Damaged couplings

• Defective weld patches

• Groove

• Pitting

• Discolouration

• Rust

• Wrinkle

• Gouge

• Buckle

• Deep scratches

• Arc burns

• Corrosion by-product



If the pipe does not need to be cut out and replaced but the damage is further than just a nick in the coating, a clock spring repair may be required. A clock spring repair system is a composite reinforcement sleeve containing a strong adhesive that is applied around the corroded area of the pipe. Clock spring repair kits can be used on pipes that have experienced up to 80% corrosion. A properly done clock spring repair will fully restore the pipe to 100% of its original strength and integrity. A clock spring repair can be applied to the outside of the pipe while the pipe is in full operation, avoiding any downtime. No cutting or welding is required. A clock spring repair can be applied in only a few hours with no special tools and not cutting or welding.

Figure 3 — Damaged or defective pipe

No matter whether it is a pup installation, a repair of a coating, or a clock spring repair that is needed, operators will need to dig around and expose the pipe to the extent that it needs to be. Make sure to clearly direct operators as to what exactly you need done, and to stay a good distance away from the pipeline or any other existing utilities. For example, a simple coating application may need less room than a full pup installation.



Pipe protectionThe main function of pipe coating is to keep water from touching the steel pipe, so the most important thing to consider when selecting a pipe coating is how well it protects against moisture. Protection against moisture is important because moisture in the coating can carry electrical current through the coating material and onto the pipe, which will start the corrosion process. Cathodic protection is also used as an anti-corrosion method for protecting steel pipe. Cathodic protection is the process of protecting against corrosion by installing an anode source to deflect corrosive influences away from the pipeline.

Corrosion is essentially an electrochemical reaction that is the enemy of any buried, metal structure. Metal or alloy that is buried in an electrically ionized, conductive environment is the most likely to corrode. In pipeline work, soil moisture and chemicals in the soil provide an ideal environment for corrosion to take place. Corrosion is intensified in pipelines that are submerged offshore, in swamps, or in riverbeds.

Wire

Sacri�cial anode

Protected pipeline (cathode)

Direct current source

Current

+

–

Figure 4 — Pipe corrosion

Another situation where an existing pipeline may need protection is during blasting operations. Using heavy equipment, mats need to be placed over rock before it is blasted. When holes have been drilled and the explosives placed in the holes, the crew places the blasting mats and madding material on top of the blasting area. The purpose of the matting and padding is to contain the blast and prevent pieces of rock from being blown into the air, causing damage or injuries. These mats are put in place to prevent the projection of fly-rock during blasting but it doesn’t completely eliminate the hazard. If an exposed pipeline is within distance of being struck with fly-rock, it should be protected with Styrofoam or another material that will protect the coating.

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