4.3.1 Screening 
Every Developer whose project does not automatically require an EIA must submit a completed Project Information Form to NRCA. The form is reviewed by NRCA staff using specific criteria, and a determination is made of the need for an EIA. 

Where the environmental impact of the project is expected to be minimal no EIA will be required. 
 

4.3.2 EIA Notice. 
Based on the assessment of the environmental impact indicated by the Project Information Form, within 10 days of receipt of the Form, NRCA might issue a notice requesting the Developer to do an EIA. Every Developer so notified will have to submit draft Terms of Reference to NRCA for approval.At this stage the Developer will be given general guidelines for conducting the EIA as well as sample Terms of Reference for similar projects if any is available. 
 

4.3.3 EIA Review 
A draft EIA report (at least six copies) must be submitted to NRCA for review and comments. A preliminary review of the draft is done within ten working days to see if any additional information is required. If additional information is needed this is requested immediately. Upon receipt of the information the NRCA EIA Review Committee will decide which external agency, if any, e.g. Port Authority, the Environmental Control Division of the Ministry of Health, Office of Disaster Preparedness, etc., must be asked to review and comment on the document as well. 

The Developer may also be granted an audience to full explain any areas of the draft report that may not be clear enough to the Review Committee. 

The review process can take up to ninety days. At the end of the NRCA inter-nal review the Developer may be granted provisional approval to initiate the project with specific conditions stipulated. 
 

4.3.4 Public Notification. 
Draft EIA reports are made available to the public at the NRCA library, at local libraries, and at Parish Councils; and the public is notified that an EIA report has been submitted, and that thirty days are allowed for comment. Any comments received from the public are brought to the attention of the Devel-oper by the NRCA. 
 

4.3.5 Public Presentation 
For some projects the Developer willbe asked to consult with the NRCA to set a date, time and venue for a public presentation/hearing. The decision on the need for public presentation depends upon the scale and magnitude of the potential impacts, and other factors such as the ecological sensitivity of the area and the level of public interest in the project. The hearing will allow the Developer an opportunity to answer questions raised by the public and to make changes in his proposals wherever necessary. 

A period of thirty days after the hearing is allowed for acceptance of written comments from the public. 
 

4.3.6 NRCA Assessment. 
The NRCA will take into account any and all comments received from the public and the concerned external government agencies and give a final response to the Developer as to whether or not his project is environmentally acceptable. The response will summarise the findings of the review of the EIA report, and indicate areas which need further attention, or impose con-ditions for approval. 
 

4.3.7 Appeals 
In cases where a project is found to be environmentally unacceptable and is not approved, the Developer may appeal to the Minister with responsibility for the environment, against the decision of the Authority within ten days after the date of the decision. 
 
 

The fees payable to NRCA by Developers for being allowed to construct and operate facilities within the coastal zone are gazetted under The Beach Control Authority (Licensing) (Amendment) Regulations, 1955. 
 

For projects of any appreciable size or scope NRCA will require that appropriate site surveys be carried out to properly identify existing marine ecosystems, and fully document the baseline conditions. 

A typical checklist of data that will have to be provided will include: 
water quality, aquatic vegetation, critical habitat, spawning, rearing and migration routes, threatened, rare or endangered species.

Normally, the information available on published navigation charts concerning sea-currents and water depths will not be adequate for detailed route planning. Project sponsors will have to be prepared to carry out appropriate current studies and hydrographic surveys in order to be able to prepare site-specific charts showing local current patterns and existing seabed contours at suitable intervals.

Site-specific data on rainfall, wind, waves and tides will be required. 
Usually, much useful data on these matters can be obtained from the Government Meteorological Office.

It will be essential to have a good appreciation of the nature of the seafloor soils. Normally, sufficient qualitative information can be obtained from grab samples and probes. However, if any trenching of the seabed to bury pipe-lines or cables is contemplated, boreholes will have be drilled, and appro-priate sampling and testing carried out to determine stratification. 

Project sponsors should take all necessary steps to ensure that appropriate investigations are carried out to clearly identify whatever geomorphological processes might be actively in force at a chosen locality, so as to be able to take such factors into account in the engineering of the project. 

5.5.1 
For example, along many stretches of the island’s south coast -from Cow Bay in the east to Sav-la-mar in the west, there is active progradation, accretion and erosion taking place at the shoreline, (refer to P.A. Wood, in Journal of the Geological Society of Jamaica, Vol. XV, 1976). 

Progradation refers to the advance of the shoreline resulting from nearshore deposition of sediments brought to the sea by rivers. 

Accretion refers to beaches that are accumulating due to inflow of sediment from external sources other than nearby rivers. 

Beach Erosion refers to the removal of material from the shoreline due to wave action. 

Any man-made facilities that are introduced into these areas of the coastal zone will inevitably interrupt the on-going natural processes and could result in unintended complications. For instance, if a pipeline or cable is laid upon the seafloor at a location where progradation or accretion is taking place, the pipeline/cable will obstruct the natural regime of sediment transport and could result in the rapid formation of dunes or sandbanks that could drama-tically alter the nearshore environmental conditions. Also, if pipelines/cables are installed at sites where there is continuing erosion, they might eventually become exposed and lose bearing support to the extent that the structural stability and integrity of the facilities are negatively affected. 
 
 

Traditionally, engineers were trained primarily to respond to the task of applying technical knowledge in the design, construction and operation of systems that were intended to produce goods and services for mankind, in the most economic and efficient manner. In more recent times however, it has become clear that many industrial practices that in the past were deemed to have been economic and efficient, were actually environmentally destructive, and therefore, in the longer term, truly uneconomic. 

And so, currently, the practicing engineer is constrained, not only by increas-ingly conservative regulations, but often also by his own heightened profes-sional sensitivity, to pay careful attention to the external effects of his works, and to strive to ensure that his projects are environmentally sustainable, i.e will not cause continuing environmental degradation.

The siting of a facility relative to the coastal zone may be of greater concern than the type of project itself, since location frequently can be the most signi-ficant factor in regard to the seriousness of the impacts that are delivered to the receiving environment. The following are some basic siting guidelines:

6.1.2 Avoid sites that are especially vulnerable to natural hazards such as earthquakes and hurricanes. (Refer to the Geological Survey Department’s hazard maps). 

6.1.3 Avoid locating facilities in areas where there is evidence of shoreline and seafloor instability. (Refer to Geological Survey Department). 

6.1.4 Selection of a route for a pipeline or cable is often dictated, to some extent, by factors such as the coastal topography, shoreline configuration, and the location of any existing onshore facilities to which the lines or cables are to be connected. However, the main objective in route selection is to avoid obstacles and to find the smoothest route to the desired water depth, maintaining as straight a course as possible. 
 

Selection of the most appropriate type of material is a very important part of the process of designing submarine pipelines. In choosing the type of material for a pipeline, the following are the most important aspects that engineers should evaluate:

6.2.1 Durability: 
The material must be able to last in the extremely corrosive marine environment. 

6.2.2 Joint Strength: 
If the material uses mechanical joints, the joints themselves will be the weakest links in the pipeline system, and thus will impose certain limitations in regard to the range of construction methods that can be used to install the line.6.1.1 Avoid routing of pipelines and cables through ecologically or archae-logically sensitive areas 

6.2.3 Joint Tightness: 
Pipeline joints need to be leakproof, especially when carrying pressurized liquids and gases. Properly welded joints are more reliable than mechanical joints.

6.2.4 Flexural Ability: 
The material must be able to flex without causing structural failure, because if the seabed is uneven the line will have to span across the low areas.

6.2.5 Resistance Impact/Puncture to 
The material must be tough enough to be able to withstand accidental impacts from boats, anchors, etc.

6.2.6 Resistance to Abrasion 
The pipeline might be unintentionally scrubbing the seafloor at times, due to wave or current action, and therefore the material could be subject to abrasive forces which could cause serious damage,

6.2.7 Requirement for Bedding 
Pipelines made of material that is not strong enough to span across irregularities of the seafloor, will require special route preparation and bedding, which can be expensive.

6.2.8 High-Pressure Capability 
For some usages, e.g. in the oil and gas industry, pipelines will have to be capable of sustaining high operating pressures, externally as well as internally; therefore the pipe material must be high strength. 

6.2.9 Flexibility of Construction 
In deciding upon the type of material that may be the most suitable for a project, very often, the criterion that is the most influential upon the decision, is the question of the ability of  the material to allow a wide range of options in the choice of construction methods.

6.2.10 
Table 3 below gives comparisons of the qualities of some of the more commonly used pipeline materials in terms of some selected performance criteria.

6.3.1 Telecommunications Cables.

Modern telecommunications cables consist of a "transmission core" of glass fibers, with outer layers of various types of materials to strengthen, insulate and protect the fibers. (See Fig. 1). 

The degree to which cables need to be protected depends upon the nature of the underwater environment. There are more hazards to cables in shallow-water environments such as coastal zone shelfs, than to cables that are deeply submerged upon the ocean floor. Deep-water cables do not need armouring. Shallow-water cables are given varying levels of external armour, (typically tapes or wires). Cables canbe classified according to their applications and the degree of armouring as follows: 

6.3.1.1 Deepwater (DW) Cable. 
Consists of the transmission core, composite power conductor, and an outer encasement of polyethylene insulation. 
 

6.3.1.2 Special Applications (SPA) Cable. 
This configuration consists of the basic DW cable, with additional protection provided by a longitudinal metallic barrier covered with a high density poly- ethylene protective layer. This type of cable is suitable for use in areas where it might be subject to abrasive forces, where fish might gnaw upon it, and at locations where cables are to be joined. 
 

6.3.1.3 Light Wire Armour (LWA) Cable. 
In this configuration the basic DW cable is given a single layer of medium strength armour wires. This type of cable is usually for burial in deep waters. 
 

6.3.1.4 Single Armour (SA) Cable. 
SA cables are very similar to LWA cables, but because this cable is not buried, the outer protective layer is made of thicker wires than those used for the LWA cables. 
 

6.3.1.5 Double Armour (DA) Cable. 
DA cables are for use in shallow, nearshore waters, where there is high risk of impact and abrasion damage. This type consists of the basic DW cable with two layers of protective steel wire. 
 

6.3.2 Electricity Cables. 

There are two types of electricity cables that are commonly used for submarine installations, viz: 

i). High Pressure Oil Filled pipe-type, HPOF; (See Fig.2) 
ii) Low Pressure self-contained and extruded dielectric, LPOF; (See Fig.3) 

6.3.1.1 HPOF Installations. 
In HPOF pipe-type systems, three cables, comprising a circuit, are installed in a steel pipe. 
 

6.3.1.1.1 Each cable consists of a stranded copper or aluminium conductor with an electrostatic conductor shielding, many layers of oil-impregnated paper tape, insulation shielding, moisture seal and a helically wound skid wire. The wire serves to protect the cable from mechanical damage during installation. Each individual cable is typically 2 to 5 inches in diameter. 
 

6.3.1.1.2 The steel pipe provides protection for the cables from mechanical damage, and prevents the entrance of moisture, as well as providing a housing for the pressurizing oil which fills the remaining space in the pipe. 
 

6.3.1.1.3 The inside diameter of the pipe must be roomy enough to allow the three cables to be pulled in without jamming. In HPOF systems, the distances between pressurizing stations is limited to around 2 kilo-metres, because, in practice, this is the maximum distance that the cables can be pulled into the pipe once it is installed. 
 

6.3.1.1.4 To protect the pipe against corrosion, various types of coatings are applied to its external surface. The coating materials may be asphaltic mastic, coal tar enamel, polyethylene or polypropylene. Also, cathodic protection is usually provided in submarine installations. 
 

6.3.1.1.5 HPOF pipe-type systems require external encasements of concrete to reduce buoyancy and provide additional protection for the pipe. 
 

6.3.1.2 LPOF Installations 
Unlike the HPOF cable, which requires field-installed pipe for cable protec-tion, the LPOF cable is complete as it leaves the factory and is therefore called "self-contained". The cables may be either directly buried or installed in ducts. Self-contained cables can be obtained in either single or triple-con- ductor design. 
 

6.3.1.2.1 The LPOF cable is made of an annular shaped conductor of stranded aluminum or copper. Like pipe-type cables, self-contained cables utilize layers of oil-impregnated paper tape for insulation. The diameter of the cable depends upon the design voltage. 
 

6.3.1.2.2 The cavity in the center of the conductor is filled with oil under pressure. The oil penetrates into the paper insulation through small openings and together they furnish the necessary dielectric strength. To assure complete saturation of oil at all times, the cable is shipped and stored on reels equipped with oil pressure reservoirs. 
 

6.3.1.2.3 The insulation is covered with an extruded lead or aluminium sheath which contains the insulating oil in the system and prevents moisture penetration. Metal tapes are applied over the sheath to give it addi-tional mechanical strength. A polyethylene jacket is extruded over these tapes. For submarine installations, armouring in the form of steel or aluminum alloy wires is applied to the cable. 
 

6.3.1.2.4 LPOF self-contained and extruded dielectric cables are well-suited for underwater use because of their flexibility, because they are delivered ready to be installed, and because they can be manufactured and installed in long lengths. 
 

During fabrication, construction and operation, a pipeline can assume many configurations and resulting states of stress. The various structural functions that a submarine pipeline can assume include: tension member, compression member, suspension member, pressure pipe, and externally loaded cylinder. Each of these con-ditions must be investigated and addressed, in order to assure the integrity and stability of the installed pipeline. 

Submarine pipelines have to be designed to withstand the range of static and dynamic loadings due to forces from gravitational influences, environmental factors, construction techniques, and operational conditions: 

6.4.1 Gravitational influences are static and include the weight of the pipe, corrosion coatings, weight coatings or anchor blocks.These loads may be adjusted for the buoyancy of the sea water or the buoyancy force may be considered as an additional loading.

6.4.2 Environmental loadings are derived from sea currents, wave action, sedimen-tation processes and seafloor variations. Environmental forces are dynamic, not readily quantifiable, and therefore can present challenges to the designer as to how to assess their influence on the pipeline.

6.4.3 If a pipeline is buried, many of the factors influencing stability become less important. However, the type of seafloor soils, the strength of sea-currents, and the regularity of the seabottom, are very significant factors in relation to the possibility or likelihood of scouring around the pipe. 

6.4.4 If the sea-bottom is uneven, the pipeline will span across the depressions, and the hydrodynamic forces created by sea currents passing over (and under) the exposed pipeline can cause vortex shedding, which can have such forceful effects upon the pipeline itself as to cause sliding and lift-off. 

6.4.5 The designer of a pipeline needs to know the methods and techniques that will be used to install the pipeline. Different installation methods will impose different configurations on the pipeline, resulting in different sets of construc-tion forces and stresses. 

6.4.6 The loadings that are imposed when a pipeline is in use come from internal pressure, surges, external pressure and support conditions. Internal pressures and surges in a submarine pipeline are no different from those that would occur in a similar land-based pipeline, and therefore do not pose any special problems for designers. External (hydrostatic) pressures are also quantifiable without any great difficulties. However, assessment of conditions of support can be challenging, due to questions such as whether the pipeline will be exposed, or buried, or spanning in places. And support conditions can change over time, due to storm action, or on-going littoral processes. 
 

Project sponsors are advised, that prior to embarking upon the preparation of their EIA, they should seek to develop and agree appropriate Terms of Refer-ence with NRCA. Typically, Terms of Reference should include at least the following information: 

§ background information identifying the need and justification for the project. 
 

§ description of the main features and activities of the project, and identification of the construction and operation processes that will pose risks to the environment or generate positive impacts. 
 

§ the anticipated timing of the project and schedule of the performance of the main construction activities. 
 
 

§ the physical environment 

§ the biological environment 

§ the socio-economic and cultural environment 

Baseline data should include: 

¨ Water quality at high and low tides. 
Water samples should be tested for Suspended Solids, Coliforms, Nitrates, Phosphates, and other parameters as may be deemed neces-sary in relation to the particular purpose of the pipeline or cable that is to be installed; 

 ¨ Water depths, bottom conditions, currents. Water circulation patterns are to be evaluated in the context of the capability of the water body to flush itself; 

¨ Identification of the existing pattern of coastline dynamics - i.e. determination of the prevailing pattern of littoral transport whether the shoreline is stable, or prograding, or accreting, or eroding; 

¨ Full descriptions of the condition of any existing natural resources, e.g. seagrass, mangroves, coral reefs. Particular attention should be paid to sedimentation, algal growth, patterns of live and dead coral, and structure of fore and back reefs.

Project Sponsors will be required to include in their EIA report, a section describing all relevant Jamaican legislative enactments, environ-mental policies, Standards and Regulations; and should identify the appropriate authority jurisdictions that will apply to the project. 
 

The EIA report should contain descriptions of the anticipated direct and indirect effects of the construction and operation activities of the project. In identifying the likely environmental effects of the construction and operation activities, it would be helpful for project sponsors to analyze them in terms of the following terminology: 
 

§ adverse effect: an effect that is large in magnitude and has important con- sequences. Both of these characteristics (i.e. large magnitude and importance) must be present, in order for the effect to deserve to be termed adverse.

§ cumulative effect: an effect that gives an incremental rise in the level of an impact, when added to other past, present and reasonably forseeable activities. Cumulative effects can result from individually minor but collectively significant activities taking place over a period of time.

§ triggering effect: an effect that induces other indirect effects. These effects are not directly generated by (the instant) project activities, but they develop because the project came into being.
 

7.5.1 The EIA should include detailed plans for monitoring and mitigating any adverse effects that might arise during construction or operation of the facilities. Any mitigatory measures recommended should be technically feasible and cost-effective, and should result in reduction of the negative effects to tolerable levels. 

7.5.2 Wherever possible, estimates of the financial and economic costs of the potentially degrading effects that the project might have upon the environment, and the costs of the mitigatory measures proposed, should be included in the EIA. 

7.6.1 Contingency plans should be presented for dealing with any emergencies that could arise during the construction or operation phases of the project, such as fire, explosion, or accidental spillage of petroleum products or other hazardous/toxic materials. The appropriate response to leaks, breaks, explosions, fire and the resulting loss of fluid, will vary according to the toxicological and physical properties of the spilled material and the potential impact it may have upon public safety and the environment. 

7.6.2 To ensure the effectiveness of contingency planning, properly trained personnel and suitable equipment must be available. Project sponsors should therefore include in their EIA, information concerning plans for providing appropriate training and equipment for the personnel who will be involved in dealing with the types of emergency situations that could arise.

7.6.3 In developing contingency plans for dealing with emergencies, it will be useful for Developers to seek consultations with the Coast Guard of the Jamaica Defence Force, and also with the Office of Disaster Preparedness and Emergency Management, since in anycase, NRCA will refer any contingency plans to those Agencies for comments, and any comments received from those Agencies will be given careful consideration by NRCA in making decisions as to the suitability of any contingency plans submitted. 

8.1.1 Throughout the construction phase of their projects, Developers will be required to maintain continuing effective liaison with the concerned government regulatory Agencies and local communities, and to ensure that any issues or concerns that might arise during this phase, are clearly understood and appropriately dealt with. 

8.1.2 The particular construction activities which will require monitoring as the work progresses will have been identified in the EIA report. Each Construction Permit issued by NRCA will indicate the required frequency for submission of written reports from the Developers to NRCA. 

The main factors that influence the methods and types of equipment that are used to install submarine pipelines are: the nature of the pipeline material itself; method of jointing; weight, size, flexibility; depth of water; velocity of sea currents; type of substrate; availability of equipment. 

Pipelines hundreds of kilometres in length have been installed in waters over a thousand metres in depth for the oil and gas industry in the Gulf of Mexico and other parts of the world. Such installations are carried out by purpose-built lay barges together with attendant unmanned mini-subma-rines ("Remotely Operated Vehicles", ROV's), and are designed and supervised by specialist engineers. Such types of projects are outside the scope of these guidelines. 

The main types of pipelines, (by different usages), that are found in the coastal zone are: oil and gas, freshwater, sewage outfalls, and cooling water intake and discharge lines. The following are some of the methods and types of equipment that are commonly used to lay these pipelines: 

8.2.1 Conventional Laybarge, (S-lay). 

The conventional laybarge is by far the most common method of installing welded steel pipelines -whether for oil, gas, fresh-water or sewage outfall. 

Under this method, standard lengths of pipe are jointed up sequentially at a series of welding stations aboard a long deck barge. The jointed-up por-tion of pipeline passes through the stern of the vessel onto an extended cradle called a "stinger". The stinger prevents the pipe from being over-stressed as it passes through the stern and curves downward into the sea. The pipeline undergoes a second bend as it comes to rest on the seafloor. The two bends give the pipeline an "S" shaped configuration as it is instal-led. In S-lay operations, pipelines can extend over 300m from the vessel, but whenever such lengthy extensions are done several tensioning and anchoring systems employing long cables have to be applied to the pipeline to keep it from becoming damaged through overstress.

8.2.2 Reel Method 

Reel laying is used for fast laying of small pipelines of up to around 300mm diameter. Under this method, the standard lengths of pipe are jointed up ashore and fed onto a reel of up to 13m diameter. The reel is then mounted horizontally on a barge or ship that uses the S-lay method of installation. 

8.2.3 Bottom Assembly 

This method consists of assembling relatively short lengths of pipes (say up to around 100m) on the seabed, using barge-mounted cranes, and then connecting up the pieces underwater by divers. This method becomes impractical in water depths of over 100m. 

8.2.4 Bottom Pull 

The bottom pull method entails pulling lengths of pipeline that have been jointed up onshore into place on the seafloor along the alignment that the pipeline is intended to finally rest. The jointed-up pipeline lengths, (gen-erally up to around 500m at a time), are set on skids ashore, parallel to the route of the pipeline. A flat barge with a sufficiently powerful pulling winch mounted on deck is then anchored several hundred metres offshore, directly in line with the final route on which the pipeline is to be laid. 

To commence installation, the pull cable is unreeled from the winch of the pull barge, taken ashore along the intended route of the pipeline, and attached to the leading end of the line that is to be pulled into place. This first length of pipeline is then pulled into alignment on the seafloor, and as the back end reaches the shoreline, pulling is halted, so that the next length of pipe can be put into place onshore and connected to the back end of the section that is already on the seabed. Pulling is then resumed and the process repeated until the total required length of pipeline is in place.

8.2.5 Surface Pull 

This method is essentially the same as the bottom pull method except that in this case the pipeline has to be light enough to float when empty, either by virtue of its own inherent lightness, or by having buoyancy elements attached. As soon as it is pulled onto alignment, water is allowed to enter the pipeline and sink it into place. 

Submarine cables are currently providing linkages in many of the world's important intercontinental telecommunications systems. Also, in many developed countries, subsea cables are in use for transmitting electrical power across waterways, from one region to another. 

The work of installing these trans-oceanic cables is performed by means of specially designed ships that povide highly maneuverable platforms loaded with sophisticated equipment for placing, pulling, jointing, coupling, and testing, the cables. 

A general outline is given below of how cable laying in the coastal zone is usually done. 

8.3.1 The first cable section to be installed is the shore end. The cable ship or barge is anchored some distance offshore and the end of the cable facing the shore is pulled from the floating vessel towards a preconstructed man-hole on land near the shoreline. For safety and protection, the near-shore section of the cable almost always has to be buried -at least where it passes through the surf zone. The cable is then secured inside the shore manhole and spliced to the previously installed land cable. This section of cable is then tested to confirm that the integrity of the insulation and the transmission characteristics of the cable itself are unimpaired. 

Installation of the deep-water segment of the system begins after the shore-end testing is completed. 

It is usually necessary or desirable to bury at least the inshore sections of pipelines and cables, giving a metre or more of cover. This is done for one or more of the following reasons: 

 
§ to protect them from destructive wave action; 
 
§ to protect them from boat/ship/anchor damage; 
 
§ to avoid instability due to bottom currents; 
 
§ to allow unimpeded recreational use of beaches.

8.4.1 Clamshell and Dragline 
In shallow water close up to the shoreline it is feasible to use clamshell and dragline dredgers to excavate and backfill. Trenches in the surf zone tend to get backfilled quickly by wave action and therefore it is necessary to plan and schedule the laying in this area especially carefully so that the operation can be carried out swiftly. Sometimes it may even be cost-effective to install temporary sheetpiles along the sides of the trenching in order to minimize excavation and backfill. 
 

8.4.2 Stationary Cutter Suction Dredge 
This type of machine can only operate where water depth is greater than around 4m. Cutter suction dredges are effective for removing even the harder types of bottom material, but they cannot operate in rough sea conditions. 
 

8.4.3 Trailing Suction Hopper Dredge 
This type of machine can dredge down to as much as 40m, and can operate in rougher sea conditions than the cutter suction; but it can only cope with the relatively softer types of seabed material. 
 

8.4.4 Marine Plow 
Towed plows have been used for digging trenches up to around 2m. deep -even in stiff clay. 
 

8.4.5 Jet Sled

When dredging machines such as those mentioned above are used for excavating trenches, the trenching is usually done before the pipeline or cable is laid. The plow, however, is more often used to cut trenching after the pipeline or cable is laid, thereby providing a guide for the alignment of the plowing. 

If the bottom material is relatively soft clay, sand or silt, a jet sled can also be used for post-installation burial of pipelines. The sled is in the form of a fork that straddles the pipeline and blasts out high velocity jets of water that penetrate and loosen the material on both sides of the line, spreading the arisings on both sides of the trenching. The sled is pulled along by a surface barge, that carries the large pumps and prime movers required to power the water jets. As the sled is pulled along, the pipeline settles into the trench behind it. 
 

8.4.6 Cutterhead Dredge on Sled 

This is another type of post-installation trenching machine that travels along a pipeline in a manner similar to the jet sled, but is felt to have the following several advantages over the jet sled: 

 
§ uses much less energy; 
 
§ can handle a wider range of soil conditions; 
 
§ cleaner cut, less disturbed cross-section; 
 
§ requires less support equipment; 
 
§ is not limited by water depth; 
 
§ can be self-propelled, thereby reducing the possibility of damage to the pipeline. 
 

8.4.7 Backfilling Trenches 

Some nearshore trenches will tend to become sandtraps, and be naturally backfilled, if they are located in the surf zone, or where there is a heavy littoral drift crossing the line. But trenches in deeper water sometimes will not backfill naturally, and the pipeline or cable in the bottom of the trench, though lowered below the general level of the seafloor, will not be fully protected. In cases like this, for full protection, the trenching will have to be actively backfilled. 
 

In the Table 4 below some of the more harmful effects that might come from the construction processes required for installation of pipelines and cables in the coastal zone are identified, and some appropriate mitigation measures suggested.

9.1.1 Throughout the operational phase of a project, the project sponsors will be required to maintain continuing effective liaison with the concerned gov-ernment regulatory Agencies and local communities, and to ensure that any issues or concerns that might arise during this phase, are clearly understood and appropriately dealt with. 

9.1.2 The particular activities and processes which will require monitoring dur-ing the operational phase will have been identified in the EIA report. Each Operating Licence that is issued by NRCA will indicate the required fre-quency for submission of written reports from the Developers to NRCA. 

9.1.3 NRCA recommends that at the time of submission of application for licence to operate, the operators of pipelines and cables in the coastal zone should name an individual who will be responsible on behalf of the project sponsors for ensuring that the operators' responsibilities to NRCA and the public, for protecting the environment, will be adequately fulfilled. 

The individual who is appointed to be the operators' Environmental Compliance Officer, shall be suitably qualified for the post, and his/her specific functions in relation to NRCA shall be as follows: 

§ to oversee on a continuing day-to-day basis, the collection of data and documentation of all site activities relating to environmental matters; 
 
§ to prepare the environmental monitoring reports called for in the approved Monitoring Plan, and submit them to the NRCA at the prescribed time intervals; 
 
§ to be available to the NRCA at all times for consultations regarding any environmental issues that might arise con-cerning operation of the pipelines or cables. 

9.1.4 Records of the following information should be maintained at site for operation and maintenance purposes:  

9.1.4.1 Detailed "As Built" drawings of all pipelines or cables and all ancillary facilities; 

9.1.4.2 Route maps and accurate data defining vertical and horizontal alignment of the installed pipelines or cables; 

9.1.4.3 Specifications for the particular coatings and/or cathodic protection systems; 

9.1.4.4 Pressure test data; 

9.1.4.5 Previous inspection reports; 

9.1.4.6 Necessary operational data; 

9.1.4.7 Records of past failures and repairs; 

9.1.4.8 Records of inspection and maintenance of safety and emergency response equipment. 

Operators of undersea pipelines will be required to implement appro- priate inspection, maintenance and mitigation procedures while their facilities are in use, so as to minimize the risk of damage to the environ-ment, injury to personnel and threats to public safety. The types of main-tenance and mitigation procedures required will depend upon factors such as the pipeline material, its location in relation to sensitive habitats, whether buried or exposed, depth of water, bottom conditions, and the characteristics of the fluid being transported. 

9.2.1 Oil and Gas Pipelines 
Oil and gas pipelines are usually made of steel, with welded joints. They are normally coated for corrosion resistance and may also have cathodic anodes attached for added protection. Larger size pipelines will have con- crete encasements to counteract bouyancy and to protect the pipeline from mechanical damage. 
 

9.2.1.1 Operators of undersea pipelines will be required to establish and maintain appropriate underwater surveillance programs to detect leaks, encroachments, and any other conditions along the route that may affect the safe operation of the pipeline. 
 
9.2.1.2 Written procedures should be established for start-up, operation, and shutdown of the pipelines, and these procedures should be scrupulously adhered to. Procedures should outline preventative measures and system checks to ensure the proper functioning of protective and shutdown devices and of safety, control, and alarm equipment. 
 
9.2.1.3 Pipeline systems should be operated so that the calculated pre-determined operating pressures are not exceeded. Over-pressure protection devices should be set to ensure that the maximum operating pressure (MOP) is not exceeded by more than 10% during surges and other deviations from normal operations. 
 
9.2.1.4 Communications equipment should be installed and maintained as needed for proper pipeline operations under both normal and emer-gency conditions. In the event of an emergency, pipeline operators should immediately notify NRCA, the Jamaica Defence Force Coast Guard, and the Office of Disaster Preparedness and Emer-gency Management.

9.2.1.5 Any necessary pipeline repairs should be performed under quali-fied supervision by trained personnel who are fully conversant with the maintenance plan and operating conditions of the pipeline, the company’s safety requirements, and the hazards to employees, the public and the environment. 
 
9.2.1.6 A written emergency plan should be established for implementa-tion in the event of system failure, accident, or other emergency, and should include procedures for prompt and expedient remedial action to safeguard personnel and limit the discharge from the pipeline system. 
 

9.2.3 Sewage Outfall Pipelines 

9.2.3.1 Sewage outfall pipelines, like hydrocarbon lines, are also most often made of steel; but unlike gas and oil pipelines, they usually operate under gravity flow, with much lower internal pressures, and therefore if leakages develop, the discharges will not be as potentially impactful as those from pressure pipelines. 

9.2.3.2 Outfall pipelines are installed for the purpose of conducting effluent out to a location in the sea where effective dilution and dispersion can be achieved. The diffusers that are usually installed at the ends of outfall lines are the elements that require the most monitoring and inspections to ensure that they are functioning properly. Diffusers have to be regularly cleaned to remove accu- mulated grease, slime and grit. Cleaning can be accomplished through flushing of the line. 
 

The great majority of faults that occur during the operating lifetime of modern telecommunications and electricity cables installed in the rela-tively shallow waters of the coastal shelf are caused, not from inherent material failures, but by physic-al damage from external sources such as dredging operations, fishing equipment, boat anchors, fish gnawing and abrasion from scrubbing on hard seafloor. Although the impacts that are delivered to the marine environment as a result of normal operations of the cables are not usually seriously degrading, nevertheless submarine cables must be monitored and inspected regularly in order to ensure that appropriate maintenance and mitigatory measures are applied whenever called for. 

9.3.1 Telecommunications Cables 
 
9.3.1.1 For repeatered undersea systems, because of the high voltages involved, the main operational hazard is electrical safety. To mitigate this hazard, all high-voltage elements in these types of systems must be equipped with key interlocks, which prevent access to hazardous voltages; and cable repairs should not be conducted on cables that are energized. 

9.3.1.2 Typically, repairs done by ship are both random and infrequent, and therefore in some regions it is common industry practice for several system owners to share a repair ship, key repair personnel, tools and other maintenance resources. This arrangement allows rapid, cost-effective response to system failures. 
 
 

9.3.2 Electricity Transmission Cables 
 
9.3.2.1 A few of the more common causes of failure of submarine electricity transmission cables are: 
 
§ impact from dredging equipment, from anchors, from commercial fishing equipment, from bottom abrasion; 
 
§ breakdown of electrical insulation from thermal, electrical or mechanical stress; 
 
§ defects in manufacture or installation.

9.3.2.2 Cable failures frequently result in explosive electrical short circuits within the system, which can cause significant damage. The short circuits are short-lived, since the installation is protected with circuit breakers which open automatically to stop the flow of current within a fraction of a second. 
 

9.3.2.3 Once a failure is detected, the exact location of the damage must be pin-pointed. Some sophisticated techniques and equipment have been developed for use in locating cable defects, but very often human divers have to be called upon to find the exact locations of cable faults. Once the fault is located, that portion of the cable is isolated from the rest of the system by closing particular valves which would have been installed at strategic points along the cable for emergency purposes. 
 

9.3.2.4 Failure of HPOF pipe-type and LPOF self-contained systems results in the leakage of insulating oil in cases where the pipe or cable is actually ruptured. The HPOF systems have the potential for greater damage than LPOF, because of the greater quantity of oil and the higher pressures that are maintained in these systems. The oils used are of varying viscosities and of relatively low toxicity. When spilled, they tend to flow easily and disperse. (HPOF and some LPOF oils are usually biodegradable). 
 

9.3.2.5 In some cases, when relatively small leaks develop in submarine cables, operators tend to keep on pumping, to maintain a slight positive pressure. This procedure is used to protect the cable system from further damage by preventing contaminating matter such as sand or water from entering through the damage break. While continuation of pumping will result in a greater discharge of oil into the surrounding waters than if pumping is completely stopped, continuation of pumping is probably more environment-ally friendly because it may save a cable installation, and thereby avoid the cost, time and environmental consequences of having to pull in a new cable. 

Project sponsors should include in their project planning, consideration of options regarding de-commissioning, dismantling or abandonment of pipelines and cables in the coastal zone, whenever such installations shall have reached the end of their life cycle and are no longer required. In planning for the termination and abandonment or removal of pipelines/cables in the coastal zone, the environmental and socio-economic problems associated with the different options should be carefully examined. 
 
 

10.1 For the safety of the public and wildlife, all equipment and above-ground facilities should be dismantled and removed, and the surface area of the land appropriately restored. Wherever circumstances allow, consideration should be given to alternative uses of sites and structures. 

10.2 It is likely that the process for removal of buried or submerged pipelines/cables would probably generate negative environmental impacts of similar extent to those delivered during the installation process. The cost of miti-gating such impacts and of restoring the routes after removing the pipelines/cables must be assessed. 

10.3 To avoid the cost and environmental impact of removing unwanted pipelines/cables from the coastal zone, it is often acceptable to leave them in place. If they are left in place they must be disconnected from any facility, and pipelines must be purged with freshwater, air or inert gas, and capped at open ends.