DEOS Cable Re-Use Committee ReportExecutive SummaryInterest in fixed ocean observing systems has been increasing for many years as it becomesapparent that the technology is now available to collect and return large volumes of data to shoreusing satellite or cable technology. Cable technology is particularly appealing since orders ofmagnitude more bandwidth can be supplied to observatories continuously at relatively lowoperational cost relative to satellite links.

Due to rapid technology advances and a downturn in the industry, first and second generationlightwave submarine telecommunications cable systems are now being retired. These providedata capacities of 560 and 1120 Mb/s, respectively, and span long oceanic distances, includingboth transatlantic and transpacific. There is currently much discussion within the scientificcommunity about the potential scientific resource provided by the re-use of these cables forseafloor and water column research.

A DEOS Cable Re-Use Committee was tasked to provide the National Science Foundation andthe Scientific Community with advice on the many technical and economic issues that must beaddressed before significant resources are committed to the acquisition and re-use of retiredtelecommunications cable systems for scientific purposes. The specific issues that the committeewas asked to address are given in the scope, which is provided in Appendix 1 of this report, andinclude those related to engineering limitations, development, power, communications,relocation, liability and spares.

The principle findings of this study are:

- There are no fundamental engineering limitations that would prevent effective re-use ofretired cables either in-situ or relocated. The system power available for the observatory nodeinstruments will be a limiting factor but only when high power consuming instruments such aspumps are used in a long or multi-node observatory. The system data transmission capacityavailable for the observatory node instruments should not be a limiting factor. The only requireddevelopment that is unique to the re-use of retired systems is for circuitry to interface theobservatory node instruments to the cable data stream and for shore based circuitry to interfacethe IP data format to the cable data stream format.

- The only significant technical issues related to the relocation of cable are that cablerecovery at cross-under with other cables is not possible and recovery of buried cable should notbe assumed. There are no significant technical issues related to re-use of cable stations.

- For equivalent architecture and complexity, re-used cable systems either in-situ orrelocated, are almost always less expensive than new cable systems but it is deemed outside ofthe scope of the committee to comment on the issue of “equivalent architecture and complexity”.

The principle recommendations from the committee are:

- All spare cable and repeaters and available associated hardware and equipment shouldbe procured. All spare terminal electronics and all available test and maintenance equipmentshould be procured unless time is available to do sufficient system design for re-used systems topermit detailed decisions. A complete set of first and second generation lightwave submarinetelecommunications cable systems documentation should be procured.

- Less expensive cable storage capabilities should be developed, e.g. coastal river barges,inexpensive university and government facility, laboratory or Navy, waterfront space.

- A careful examination should be made of all terms and conditions in all of the existinglicenses and permits granted to the original cable system owners as well as all applicable lawsand treaties.

- Third person liability costs and indemnification should be evaluated with an insurancecarrier.

- Working groups should be established to- build upon the work started by IRIS Ocean Cable with respect to the re-use of

retired and to be retired cable systems,- develop a capital and expense investment time line to protect the ability to re-

use retired and to be retired cable systems until decisions can be made and- develop specific plans for cable re-use for input to the re-use decisions.

1. IntroductionFirst and second-generation electro-optical transoceanic telecommunications cable systems arebeing retired. There is currently much discussion within the scientific community about thepotential scientific resource provided by the re-use of retired cables for seafloor and watercolumn research. This DEOS Cable Re-Use Committee was tasked to provide the NationalScience Foundation and the Scientific Community with advice on the many technical andeconomic issues that must be addressed before significant resources are committed to theacquisition and re-use of these cables for scientific purposes. The committee scope is providedin Appendix 1 of this report.

Interest in fixed ocean observing systems has been increasing for many years as it becomesapparent that the technology is now available to collect and return large volumes of data to shoreusing satellite or cable technology. Cabled observatories are essential to the Ocean Sciences(NRC, 2000), and the impacts of these observatories have been discussed in a succession of NSFworkshops and NRC reports (National Research Council, 1998; National Research Council,2000; National Academy Press, 2003). Cable technology is particularly appealing since orders ofmagnitude more bandwidth can be supplied to observatories continuously at relatively lowoperational cost relative to satellite links.

The downturn in the telecommunications industry and rapid increases in available bandwidthhave made the continued operation of these early generation cables by the industryuneconomical. The dramatic increase in capacity, coupled with over optimistic projections fortraffic has led to the down-sizing of the industry and retirement of the older systems.

Submarine cables require periodic amplification of the signals being transmitted. In the first andsecond generation optical cables, installed between 1988 and 1995, this was accomplished bychanging the incoming optical pulses to a repeater into electrical pulses, regenerating them andthen changing them back to optical pulses for further transmission. These repeaters were spacedat a distance of approximately 40 to 150 km depending on the specific system design. Newersystems, installed beginning in 1995, operate with optical amplifiers rather than signalregenerators, making it possible when appropriately designed to add additional signals atdifferent light wavelengths without changing the cable system. This technology permits large

increases in data capacity, with the newest systems capable of transmitting over 1 Tb/s, or asmuch as 2,000 times the capacity of the systems being retired.

The fiber optic telecommunications cables being retired by the telecommunication industry andunder consideration for scientific reuse include three Pacific systems—Hawaii-4 (HAW-4),Trans-Pacific Cable-3 (TPC-3), Guam-Philippine-Taiwan (GPT)—and four Atlantic Systems—Trans-Atlantic-8 (TAT-8), TAT-9, TAT-10, and TAT-11 The length of these cables (Figure 4) is4238km (HAW-4), 9161km (TPC-3), 3749km (GPT), 6705km (TAT-8), 8358km (TAT-9),7354km (TAT-10), and 7162km (TAT-11). The transfer of all or portions of these systems toscience is currently in negotiations. A facility for ownership transfer is IRIS Ocean Cable, Inc.(IOC), a not-for-profit corporation formed by The IRIS Consortium in consultation with theNational Science Foundation to acquire ownership of retired telephone cables for science. IOCcurrently owns two retired coaxial telephone cables: TPC-1 (Guam-Japan) with the University ofTokyo and Hawaii-2, which serves the NSF-funded Hawaii-2 Observatory (H2O). Other systemswill also be made available as retirement of other systems occurs during the next few years.Appendix 2 provides a list of cables that have been retired or will be in the near future.

The specific issues that the committee was asked to address are given in the scope and includethose related to engineering limitations, development, power, communications, relocation,liability and spares.

2. Technical Description of Systems2.1. Transmission and electrical properties

AT&T submarine cable systems being considered for scientific reuse include both first andsecond generation designs. The principal differences are bit rate and transmission wavelength.The first generation systems, designated SL280, operate at a rate of 295.6 Mb/sec per fiber pairand at a wavelength of 1.30 µm. Second generation systems, designated SL560, operate at a rateof 591.2 Mb/sec per fiber pair and at a wavelength of 1.55 µm.

All systems now being considered for reuse have two active fiber pairs plus a spare fiber pair.Spare fibers can be switched in as needed on a section-by-section basis. To the best of ourknowledge as of the date of this report, during the active commercial lifetimes of these systemsthere have been only two instances where switching to spare fiber sections was required.Switching of fibers at repeaters using supervisory units in the terminal facilities provides apowerful means of testing these systems and the spare fibers and components in the repeaters.Terminal facilities include supervisory equipment for monitoring repeaters and for switching tospare fibers if needed.

All systems are DC powered from the ends and operate at a current of 1.6 A. It is important thatequipment incorporated into these cable systems for scientific purposes be designed to maintainthis current level throughout the system implying that observatories must be connected in serieswith the cable power system. The maximum voltage that should be applied to these systems is8.0 kV.

Repeater spacing, both within a single system and between systems, varies widely. The rangefor all systems is 40 to 150 km. The repeater voltage drop for SL280 systems is 22.3 V and forSL560 systems is 43.0 V. The DC resistance of the cable is 0.71 Ω/km for both generations ofsystems, so the voltage drop in the cable is 1.14 V/km. This information is required to calculatepower available to science instruments and will be discussed later in the report.

Third generation AT&T systems which were installed starting in 1995 contain optical amplifierrepeaters instead of regenerative repeaters. Early optical amplifier systems used 21-mmdiameter cable with the same electrical and mechanical properties as the cable used inregenerative systems, while later systems almost all used a 17-mm diameter version of the cablewith lower weight, lower strength, and a DCR of 1.0 Ω/km. The fiber count in these systemsvaries from four to eight. The operating current depends on the number of fibers, but in all casesis lower than the current in regenerative systems. While we expect that some of these systemswill be decommissioned over the next few years, at this time we know of no specific plans byany owner to do so. Consequently, these systems will not be considered further in this report.

2.2. Mechanical propertiesAll systems use the same repeater housings, which, with their associated cable couplings, weigh3.8 kN in air and 3.1 kN in water. Cable couplings are designed to allow handling of repeatersaround 3-meter diameter or larger drums and sheaves. Smaller equipment may require specialhandling arrangements.

All of the AT&T systems use SL21 cable or equivalent. The deep water version, commonlycalled LW, and the special applications version, called SPA (originally fishbite protected) havethe following properties:

Property LW SPA

Diameter 21 mm 32 mm

Weight in air 8.25 N/m 13.4 N/m

Weight in water 4.76 N/m 5.40 N/m

Hydrodynamic constant 58 deg-kts 50 deg-kts

Nominal transient tensile strength 81 kN 82 kN

Nominal operating tensile strength 53 kN 58 kN

Breaking strength 107 kN 107 kN

Bending diameter, no load 2.0 m 2.0 m

Bending diameter, >10 kN load 3.0 m 3.0 m

The principal value of this information is to permit calculation of cable recovery rates for variouswater depths and sea states. LW and SPA recovery rates are limited primarily by cableproperties. Similar data are available for the various armored cable types, but recovery rates areusually limited by shipboard handling considerations rather that cable properties. Three types ofarmored cable are normally used in regenerated SL21 systems:

Cable type Abbreviation

Light wire single armored LWA

Single armored SA

Double armored DA

All armored cables have limitations on the maximum depths from which they can be recoveredat reasonable speed (practical minimum 1 knot). This limit depends in part on the weatherconditions assumed for the recovery. Since a particular length of cable may need to be recoveredby itself, by a weaker cable adjacent to it in the system, or by a stronger cable adjacent to it in asystem, the maximum depth also depends on the particular system configuration and may varyalong the length. Most system cable configurations result in maximum recovery depths ofapproximately 2000 meters or less for single armored types and approximately 1000 meters orless for double armored. Single armor and double armor (SA and DA) cable use is limited toshallow water and rough bottoms. They cannot be recovered from deeper than 2 km because oftheir heavy weight. When buried, recovery of cable is both expensive and high-risk.

Spares exist for all cable types.

3. Cable re-use opportunitiesThere are four generic possibilities for the use of retired cable systems: 1) short segments that donot require signal regeneration in a system repeater, 2) re-use in-place, 3) partial move utilizingthe existing cable landings, and 4) total move of long segments requiring a new cable landing.The economic benefits of reusing existing systems are particularly strong when the observatoryspans long linear distances. The serial nature of nodes in this configuration requires the samehigh reliability designed into existing systems. As a rough example, the cost of just buying thecable and repeaters required for a 5,000 km observatory could be as much as $50,000,000. Forroughly 20% of this cost, an existing system can be recovered and redeployed ready forinstallation of science nodes and instrumentation.

3.1. Short segmentsSections of cable can either be taken from the spare cable resource or recovered from the oceanfloor to provide observatory infrastructure. Since these segments do not contain repeaters, thepower and data transmission are restricted only by the characteristics of the cable and availabletechnology. The length is constrained only by the data rate and the transmitter, fiber and receivercharacteristics. For lengths up to approximately 100km, data rates on the order of a Tb can beachieved using current technology. The only advantage of re-using cable instead of using newcable for this purpose is that the former should be considerably less expensive. In the past thecost of new deep water cable was approximately $8,000/km but we are aware of recent sales atsignificantly lower prices due to current market conditions. Science uses for such cable segmentsinclude coastal observatories and extensions to existing and planned observatories. As with anycabled observatory requiring a new shore landing, cost will depend to a large extent onconditions and infrastructure at the cable landing. The Hawaii Undersea GeophysicalObservatory (HUGO) (Duennebier, et.al., 2002) utilized spare SL cable for its infrastructure.

3.2. Re-use in-placeCable systems that were installed in areas of scientific interest can be used in-place. The Hawaii-2 Observatory (H2O) is an example of such an observatory. H2O was installed on a coaxialtelecommunications cable about halfway between Hawaii and California. Compared to the SLcable systems, however, the coaxial Hawaii-2 system has about three orders of magnitude lowerdata bandwidth and less than 1/4th the electrical power.

Re-use in-place requires that the cable be cut, lifted to the surface, and that an observatory nodeconnection be spliced into the cable. Two types of connections are possible: terminal – wherethe connection is at the cut-end of the cable, and in-line – where the cable continues on bothsides of the connection. While an in-line connection requires the addition of cable ofapproximately 2½ times the water depth and thus is more expensive to install than a terminalconnection, an in-line connection allows the cable to be used for observatories over its wholelength. The constant-current (series) electrical power system of these cables requires that each in-line observatory node draw power from the cable by a voltage drop across the node connection.The voltage drop times the cable current yields the electrical power consumed by thatobservatory. Since the resistance in the cable and the repeaters also draw power by reduction inthe voltage, there is a limit to how much power can be removed from the system. In thehypothetical power curve shown below, 16 in-line observatory nodes, each drawing about 900W, are connected to the 4200 km HAW-4 cable at 250 km intervals (Figure 1). This examplerequires that the cable be powered at both ends at about 7500V plus margin for earth potentialdifferences. This example assumes fixed observatory loads and uniform spacing, but spacingand loads can vary without changing the result as long as the source voltages and currents remainthe same. In this example, the observatories could share four 100Mb/s data channels, or about25 Mb/s continuous rate per observatory (Figure 2).

Figure 1: Potential use of the HAW-4 Cable showing the cable voltage curve with 16observatories, each drawing 900 W from the cable.

Figure 2: HAW-4 Cable Map showing 16 observatory nodes (stars), each capable of supplying900 W of power and 25 Mb/s data flow.

3.3. Partial moveRetired cables could be cut, and the cable recovered from the ocean floor onto a cable ship, thenre-laid along a path more appropriate for observatory science needs. If HAW-4, for example,were cut near the center (close to where the voltage goes through zero), then about eightobservatories similar to those in the example above could be installed on each side (Figure 3).Partial move has several advantages. As the cable is recovered, the in-line and terminal nodeconnections can be spliced into the cable aboard ship, eliminating the requirement for cutting andsplicing a previously laid cable. Where many nodes are to be inserted, this could yield aconsiderable cost saving. A second advantage is that the cable landing is not changed, and a newshore landing is not required. The figure below shows one possible use for HAW-4, using thecable for a series of observatories east of Hawaii and for observatory nodes west of the Gordaand Juan de Fuca plates (complementary to the NEPTUNE Project). Each node can deliver anaverage of 900 Watts and 25 Mb/s for observatory support.

Figure 3: Possible re-use of the HAW-4 cable for observatory nodes east of Hawaii and west ofthe Gorda and Juan de Fuca plates.

3.4. Complete relocationComplete relocation involves recovery of a large section of cable from the ocean floor and re-usein a completely different location. While this option is certainly the most expensive of thosedescribed, it also can provide observatory infrastructure in areas where it might otherwise beimpractical, such as the southern ocean. Complete relocation might also supply a large numberof fixed observatories in regions where there is a strong need for continuous monitoring ofenvironmental parameters, such as the equatorial Pacific and the Kuroshio current.

A map of some of the cable systems being retired this year and in the near future that terminatein North America and Hawaii is shown below. (Figure 4)

Figure 4: Map of Undersea Light-Wave Cables Being Retired (Butler, 2003)

The map below (Figure 5) shows, if the cables could be made available, how they might berelocated to more interesting areas in the southern ocean. Each of these segments could support astring of from 6-10 observatories drawing 800 W each depending on the intended uses and cablelength. Each of these 6-10 observatories could easily support the science requirements of a high-rate DEOS buoy. Even though the map was generated for a buoy scenario, the benefits of reusingcable to support this research effort are obvious. With slight modifications of the desired buoylocations, the benefits are even greater. A significant amount of the operational costs of theDEOS buoys is in maintaining the power generators and paying for the satellite data link. Forsites that are within a reasonable distance, say less than 1000 km, of a suitable shore landing, it isworth considering replacing the diesel generators and satellite telemetry hardware in buoys ofthis type with a section of a reused system. This has the obvious benefits of increasing powerand data availability and significantly reducing operational costs.

Figure 5: Example of moving sections of cables to the southern ocean. The DEOS observatorysites are shown for comparison. Green and red triangles are funded and planned observatories,respectively. Green and red circles are funded and planned air-sea flux sites respectively (DEOSSteering Committee, unpublished data).

Opportunities for re-use requiring cable relocation need to consider whether newer cables crossover the older ones. In such cases, long sections, several thousand km in length are available forrecovery and longer sections can be obtained by recovering the cable on both sides of the crossand appropriately slicing the two sections together.

While this committee can advise on whether re-use of the retired systems is a viable alternativeto the use of new cables for fixed ocean observatories, it is not in a position to determine whetherthis use is justified by science and monitoring priorities. It appears that the opportunities forcable re-use for RIDGE and MARGINS priority sites and for oceanography, marine biologicaland other initiatives are considerable. The possibility of large amounts of power and high datarates – compared to what has been available previously – challenge the community to envisionnew experiments that will take advantage of this resource. The Global Ocean Observing Systemshould also be able to benefit strongly from cable re-use to fill its environmental monitoringmission.

3.5. Military Cable SystemsThe U.S. Navy maintains the majority of Government-owned seafloor cable systems that couldbe of potential value for reuse for ocean observatories. These Navy cables include several kindsof test and tracking ranges typically close to shore, special use systems and a few undersea

information and power cables in a variety of locations. The U.S. Army has relatively fewsystems that could be used in any environmental monitoring application. The U.S. Air Force hasdeveloped a methodology of leasing much of the information transfer capacity and has utilizedDefense Information Systems Agency (DISA) as its agent in most of this effort.

There is no single official point of contact or office working to coordinate in-water governmentcable information. The closest thing to that is a relatively new office in the Department of theNavy, established several years ago to better interface with commercial industry and other usersof the ocean floor. During the rapid expansion of the telecommunication systems in the lastdecade, it became very clear that interface with the commercial industry was vital to protectthose Navy systems that were installed on the seafloor. The decision was made to concentratethese efforts in this new office of the Naval Facilities Engineering Command (NAVFAC) locatedin the Washington Navy Yard. The present point of contact is Mr. Herb Herrmann, ph-202-433-5319, e-mail: Herbert.Herrmann@navy.mil. During the effort to establish this NAVFAC officeas the focal point for cable information, Mr. Herrmann worked to establish contact within the USAir Force, US Army Corps of Engineers and DISA. Mr. Herrmann is in contact with many ofthe offices involved and has excellent first hand knowledge of this aspect of the architecture. Forthe foreseeable future he is probably the most effective single point of contact concerningmilitary and other government owned and operated cable systems. This NAVFAC office andMr. Herrmann have been advised of the needs of the NSF with regards to the possible reuse ofretired military cable systems and are prepared to support these needs in keeping within existingsecurity guidelines and other government controls. This office will also be able to disseminateinformation concerning the schedule for the retirement of military cable systems. It isrecommended that the NSF establish contact with this office to be advised of possibleopportunities as well as providing assistance for complying with the security issues addressed inSection 5.5 of this report. Note however that others in the science community are pursuing thisarea and NSF should stay abreast of those activities.

The nature of the military systems is multi-faceted with the most attractive items for oceanobservation re-use being the ranges. This includes the tracking range at St Croix, which is beingretired due to the closure of the Vieques Island Ordnance range. The ranges remaining openinclude, for example, AUTEC (Tongue of the Ocean) in the Bahamas, Southern CaliforniaAcoustic Range off the West Coast, and Pacific Missile Range Facility (PMRF) off the coast ofHawaii. These ranges have multiple cable runs to provide data from a complex of sensorstracking vessels, objects, or acoustic events within the water column over a fairly large area to ashore processing facility. There are also several cables in existence from the retired SOSUSsystems on both East and West Coasts of the US. These systems have been declassified but theconditions of the shore landing cables and availability are not accurately known at the moment.In addition, it should be noted that the condition of the at sea cable is unknown. If available,some investment for re-use would likely be required. These system cables were designed forcollection of acoustic information from a widely disbursed field of long range, low frequencysensors and most are 30-year-old technology. This is certainly not a complete listing but rather aset of examples of assets that are in the water and potentially available at some point in thefuture.

3.6. Hardware DevelopmentDevelopment efforts are needed to utilize retired optical cables for observatory use. Oneadvantage of these systems is that they are effectively identical in most respects, and hardware

built for one will work equally well on another, significantly lowering development costs.Hardware for node connections, power supplies, and communications systems is required. Someproposals are provided in Appendix 3.

4. Technical Issues Associated with Cable Re-useThis section of the report addresses various technical issues related to cable re-use.

4.1. Engineering LimitationsThe charge to the Committee asked for advice on engineering limitations related to cable re-use,i.e. “What are the engineering limitations related to the re-use of retired fiber optic cables?”.

No fundamental engineering limitations were identified that would prevent effective re-use ofretired cables. Various technical operational constraints were identified, however, and these arediscussed in the following sections. In addition, it is judged that limitations are most likely costdriven. As discussed elsewhere in this report, re-used systems can provide power and datatelemetry adequate for existing and near-term planned science scenarios. However it should benoted that new observatory systems are being designed to provide substantially more power anddata telemetry capabilities that may be useful for future generation science scenarios.

4.2. PowerThe charge to the Committee asked for advice on power issues related to cable re-use, i.e. “Whatare the issues related to the power systems associated with these cables? What power would beavailable at the seafloor for supporting sensors in the seafloor and water column?”.

As described in Section 2.1, the SL280 and SL560 generations of systems were designed to bepowered from the shore stations with a constant DC current of 1.6 amps. The associated shorebased power plant contains redundant power converters and when fully equipped can provide avoltage of up to 7.5 kV. For a specific existing installed system, the power plant may not befully equipped and thus only a lower maximum voltage would be available. In such a case,realization of 7.5 kV would require adding plug-in power stages and possibly equipment bays tohouse the added stages. These can be obtained by using spares or by cannibalizing the redundantpower converters. The downside of cannibalizing is that certain single failures would cause anoutage until the repair could be effected, possibly not a significant issue for observatoryoperation.

The cable and repeaters should permit the applied voltage to be increased up to 8 kV but thiswould require the purchase of a new power plant. While use of the existing power plants mayindeed be the best solution for powering the cables, these provide reliability well in excess ofmost science needs. There are relatively inexpensive replacement power supplies that would beadequate for the observatory systems.

As stated in Section 2.1, the cable DC resistance is 0.71 ohms/km and the repeater voltage dropis 22.3 and 43.0 volts for SL280 and SL560 repeaters, respectively. Assuming average repeaterspacings of 70 and 135 km for SL280 and SL560 systems, respectively, leads to an averageaggregate power drop along the cable of approximately 2.3 W/km. Consequently, with thestandard 7.5 kV shore based power plant, the aggregate average power available for observatorynodes would be approximately 9.7, 7.3 and 5.0 kW for 1000, 2000 and 3000 km length systems,respectively

Power buffering through the use of batteries and/or capacitors at the user node could providepeak powers in excess of these values. Also, the ability to turn user instruments on and offshould be a requirement along with ground fault over current monitoring

Appendix 4 lists the power requirements for various observatory node instruments. Acomparison of the instrument power requirements with the available power indicates that powerwill be a limiting factor but only when high power consuming instruments such as pumps areused in a long or multi-node observatory.

4.3. CommunicationsThe charge to the Committee asked for advice on communications issues related to cable re-use,i.e. “What are the issues related to communications protocols and the potential for translatinglegacy technologies to other protocols (e.g. TCP/IP) in use on the Internet?”.

The candidate cable systems provide telecommunications standard interfaces at 140 Mb/s. TheSL280 systems provide 2 such interfaces on each of 2 fiber pairs for an aggregate data capacityof 560 Mb/s. The SL560 systems provide 4 such interfaces on each of 2 fiber pairs for anaggregate data capacity of 1120 Mb/s. The standards for these 140 Mb/s signals are defined andequipment exists to interface the Internet world to this telecommunications industry world. Suchinterfacing equipment would be needed on the shore and in the observatory nodes, if InternetProtocol is employed.

The actual transmission signal on each the fibers is a custom 296 Mb/s format for the SL280systems and a custom 592 Mb/s format for the SL560 systems. These rates can be used fortransmission as an alternative to the use of 140 Mb/s format transmission. Equipment does notexist, however, to generate 296 or 592 Mb/s signals from the Internet signals or to transmit suchsignals on the shore and, consequently, new custom equipment would be required in the shorestation and in the observatory nodes. In addition, cable system repeater fault location and controlwould require off line testing with standard SL test equipment.

Buffering and/or time division multiplexing at the user node can provide higher individualinstrument peak data rates. Also, for observatory systems of length less than one repeater spanthe SL transmission protocols need not be used and data rates can be much higher than the ratesdiscussed above.

Appendix 4 lists the data requirements for various observatory node instruments. A comparisonof the instrument data requirements with the available data transmission capacity indicates thatthe cable data capacity should not be a limiting factor.

4.4. Cable System RelocationThe charge to the Committee asked for advice on issues related to cable system relocation, i.e.“What is the feasibility and approximate associated cost of relocating retired cables? Three casesshould be considered – cable reuse in place, cable re-use with some relocation but using originalshore station and cable re-use with relocation of the cable and establishment of a new landstation.”. The technical issues are addressed here. The cost issues are addressed in a followingsection.

Significant lengths of coaxial undersea cable systems have been relocated, e.g., a US Navy re-use of a TAT system entailing the recovery and relay of a total of a few thousand kilometers

including repeaters. A few hundreds of kilometers of lightwave undersea cable includingrepeaters have been picked up and re-laid.

During recovery, the cable should be visually inspected for insulation damage and opticallytested. The need for repair will depend upon bottom conditions and crew experience. With goodbottom conditions, a reasonable assumption is a maximum of 1 or 2 repairs per a few thousandsof kilometers of recovered cable. Repairs can be accomplished on board the cable ship.

Particular attention needs to be paid to understanding where other cables cross and come close tothe cable being recovered. Cable recovery at cross-under locations is not possible. Cable cuttingon both sides of the crossing is necessary with resplicing of the two pieces.

Recovery of buried cable usually cannot be justified.

Re-laid cable needs to satisfy the usual bottom and depth conditions, e.g., lightweight cableshould not be laid on rocky ridges.

These are the only significant technical issues related to the cable. There are no significanttechnical issues related to the cable stations.

4.5. Development RequirementsThe charge to the Committee asked for advice on development issues related to cable re-use, i.e.“What are the re-engineering/engineering development issues that must be dealt with in order tore-use the submarine cable systems likely to be retired?”.

The only development issues identified by the committee that are both required and unique to there-use of the systems likely to be retired are

- development and procurement of circuitry to interface the observatory node instrumentsto the cable data stream and power and

- development and procurement of shore based circuitry to interface the IP data formatcurrently the consensus format of the science community to the cable data stream format.

Two other development items of note are

- modification and replacement of the shore based high voltage power plant to provide 8kV at 1.6 amps but see Section 4.2 for a discussion of the issues related to this subjectand

- mechanical arrangement to interface an observatory node to the cable but this should besimilar if not identical to the arrangement used with new cable.

4.6. ReliabilityAlthough not specifically requested in the Committee scope, the reliability of re-used cable andrepeaters was addressed.

The reliability of in-situ equipment should continue to exhibit telecommunications industryperformance, i.e., 25 years minimum life and probably longer. Significant engineering effortwent into designing systems that could meet this objective. Reliability performance to date onthe AT&T systems considerably exceeds the objectives and expectations of the systemsdesigners. The reliability of relocated cable and repeaters should exhibit similar performance,assuming that standard telecommunications industry care is taken during the recovery and re-lay.

Reliability issues for new equipment on re-used systems should be similar to those for theequivalent equipment on new systems of equivalent configuration.

Detailed failure mode analysis for node equipment should be required and mitigated as necessaryin both re-used and new systems.

4.7. Test EquipmentAlthough not specifically requested in the Committee scope, test equipment needed toadminister, operate and maintain the system was addressed.

Test equipment that should be included as part of any retired cable system procurement needs tobe defined. This is in addition to the definition of any new test equipment that will be requiredbut is not unique to the re-use of retired systems.

5. Economic and Other Non-technical Issues Associated with Cable Re-use5.1. Cost of Relocation

The charge to the Committee asked for advice on issues related to cable system relocation, i.e.“What is the feasibility and approximate associated cost of relocating retired cables? Three casesshould be considered – cable reuse in place, cable re-use with some relocation but using originalshore station and cable re-use with relocation of the cable and establishment of a new landstation.”. The cost issues are addressed here. The technical issues are addressed in a previoussection.

5.1.1. Wet PlantThe following approximate cost estimates are extracted from Appendix 5 and suggested for thewet plant for initial planning purposes. Examples of the use of these numbers are provided in theappendix.

Cable and repeater pick-up – range of 0.5 to 2.0 M$ per thousand kilometers of pick-up.This assumes – a ship cost of 20 to 80 K$ per day but this depends strongly on opportunityand market conditions; a 50 km per day pickup rate but this depends strongly on bottomconditions.Ship transit – range of 50 to 200 K$ per thousand kilometers of transit, with the sameassumption and caveat for ship cost.Re-lay – range of 100 to 400 K$ per thousand kilometers of re-lay, with the sameassumptions and caveats.Observatory node installation – 100 to 200 K$ per node for non-relocated cable andnegligible added cost for relocated cable. The relocated cost assumes the installation will bedone during pick-up and ship transit operations. Also note that this does not include theactual installation of the observatory instruments.Survey – survey costs are entirely dependent on the specific route and node location and needto be estimated on a case-by-case basis. This is beyond the scope of the committee.5.1.2. Shore Stations

Re-use of space in original shore station, i.e. cable re-use in place and cable re-use with somerelocation. – Assuming the existing owner of the station maintains ownership and not includingnew hardware, the costs for re-use are primarily related to space rental and liability coverage,and are very site dependent and open to negotiation. For the case of station purchase, rental cost

is replaced by purchase price, if any, and on going ownership costs. The committee is not in aposition to provide estimates for either of these cases. Some estimates are available to IRISOcean Cable (http://www.iris.iris.edu/cable/info.htm) but the committee is not in a position toconfirm those numbers.

Establishment of new shore station. – Not including new hardware, the major costs for a newshore station are associated with land, right-of-way, building, power, communications, groundfarm, dry civil works, survey, cable landing, wet cable protection, cable installation includingburial as necessary, permits, environmental, liability, attorney fees and on going ownership.These costs are very site dependent and the committee is not in a position to provide estimates.

5.2. Relative Cost for Relocated and New SystemsThe charge to the Committee asked for advice on the relative cost for relocated and new cablesystems, i.e. “In what circumstances will the relocation of a cable and the salvage of repeaters beless expensive than establishing a new system?”.

Consideration was given to the significant and unique cost factors associated with new cableobservatory systems and with relocated systems, both partial and complete relocation. Many ofthese factors are discussed elsewhere in this report. The committee concluded that for equivalentarchitecture and complexity, cable re-use is almost always less expensive. It is outside the scopeof the committee, however, to comment on the issue of “equivalent architecture and complexity”which includes the advantages and disadvantages of various architectures.

5.3. LiabilitiesThe charge to the Committee asked for advice on issues related to liabilities associated withcable system re-use, i.e. “What are the liability issues associated with ownership and use?”.

Various licenses, permits and ownership agreements are granted and/or entered into as part of theconstruction and operation of a telecommunications undersea cable system. In addition, variousnational laws and international treaties govern such systems.

Typically, the owners of a cable system enter into a Construction and Maintenance Agreement(C&MA) governing the relationship between them in the joint enterprise to construct andmaintain a cable system. The cable system is composed of different segments, usually the cablestations in the landing countries and the submarine cable between the cable stations. The C&MAdefines these segments and identifies ownership of them. Typically, one or more parties fromthe particular landing country own the respective cable stations and the submarine cablesegments between the cable stations are owned in common undivided shares as specified in theC&MA. The C&MA normally provides for responsibility for claims made against any party tothe agreement which is usually shared among the owners.

The owners also enter into Supply Contracts for the construction of the system. These establishthe relationship between the owners and the suppliers and usually contain provisions regardingwarranties and liabilities.

The governments of various jurisdictions in the countries in which the cable system terminatesrequire various licenses and permits. The licenses and permits can contain provisions governingliabilities and responsibilities affecting the owners.

The licenses, permits, C&MA, Supply Contracts, laws and treaties cover a multitude of issuesrelated to rights and responsibilities that would be expected in some way to transfer to a new

owner. Of particular interest to the question of cable re-use are those rights, responsibilities andassociated costs related to environmental, liability, including third party, and final deactivationand abandonment. The current parties to the particular C&MA may want relief and orindemnification from third party, including fishing industry, and environmental claims. If acable system is procured only from the US to a point in international waters, then the parties mayonly have to be concerned with US laws and international treaties.

Also, the licenses and permits may contain conditions related to change of ownership andtermination of use for telecommunications.

Consequently, careful examination needs to be made of all terms and conditions in all of theexisting licenses and permits granted to the original cable system owners as well as all applicablelaws and treaties. In addition, third person liability costs and indemnification should beevaluated with the insurance carrier of the new owner, e.g., IOC.

5.4. SparesThe charge to the Committee asked for advice on issues related to the procurement of spareequipment associated with retired cable systems, i.e. “How much liability should be incurred inthe acceptance of spares related to each of these retired systems? Should all spares beaccepted?”.

It is reported (Butler, 2003) that AT&T can make available approximately 700 km of SL280 andSL560 cable of 5 cable types, lightweight to double-armored, in 41 sections of 1 to 40 km length;15 SL280 and 23 SL560 repeaters; and various shore-based transmission terminal, shore-basedpower plant and repeater electronic circuits. Information from that report is given in Appendix 6.The primary issues related to the procurement of this spare equipment is how much, when, wherethe spares should be stored, the costs associated with obtaining, storing, replacement and finaldisposal, and use of the spares for other observatory applications such as node extensions.

It is clear that there is considerable pressure to minimize the procurement of spare equipmentbecause of the costs involved. An observatory system, however, cannot be maintained withoutspares or the ability to newly manufacture replacement parts. New manufacture of SL280 andSL560 equipment would be very expensive and in most cases, possibly in all cases, impossible.Consequently, a no decision on the procurement of the spares, which includes not making adecision and sufficiently delaying a decision, is in effect a decision not to reuse the retiredcables. The cost of this procurement is the moving to a new storage facility, if required, andstorage.

The Committee makes the following recommendations with respect to the spares.

- Procure all spare cable and available associated cable hardware (jointing kits, terminationhardware, branching units, etc.). In addition to protecting the ability to re-use retiredcables if so desired, this equipment has application for other observatory uses even if thedecision is made not to re-use systems, e.g., for extension cables in currently plannedobservatories and possibly for the backbone cable of coastal observatories.

- Develop other less expensive cable storage capabilities, e.g. coastal river barges,inexpensive university and government facility, laboratory or Navy, waterfront space.Possibilities for new storage locations for the cable are suggested in Appendix 6.

- Procure all spare repeaters and associated equipment to protect the ability to reuse cablesystems until a decision is made.

- Procure all other spare terminal and repeater electronics unless time is available to dosufficient system design for re-used systems to permit detailed decisions.

- Procure all available test and maintenance equipment unless time is available to dosufficient system design for re-used systems to permit detailed decisions.

- Although not limited to spares, procure all available documentation on the specifications,operation of, design, lay, and history of each candidate cable system.

5.5. SecurityAlthough not specifically requested in the Committee scope, certain security issues related to there-use of retired cables were addressed.

The only security issue unique to such reuse is the impact on nearby military cables during therecovery of a cable that is being relocated.

Other security issues are common to any ocean observing system in an area of concern to theDOD. The primary threats are from external aggressors – attaching unapproved sensors to thesystem and making unwanted measurements, accessing data from approved sensors, subverting aPI who has an approved sensor, or taking advantage of approved sensors without the knowledgeof the PI. For information on these issues please see NRC (2003).

6. Findings and Recommendations6.1. Findings

The following findings have been discussed in previous sections of this report.

1. There are no fundamental engineering limitations that would prevent effective re-use ofretired cables either in-situ or relocated. Limitations are most likely cost driven. SeeSections 4.1 and 5.1 for additional information.

2. The system power available for the observatory node instruments will be a limiting factor butonly when high power consuming instruments such as pumps are used in a long or multi-node observatory. See Section 4.2 for additional information.

3. The system data transmission capacity available for the observatory node instruments shouldnot be a limiting factor. See Section 4.3 for additional information.

4. The only significant technical issues related to the relocation of cable are that cable recoveryat cross-under with other cables is not possible, recovery of buried cable should not beassumed and re-laid cable needs to satisfy the usual bottom and depth conditions. There areno significant technical issues related to re-use of cable stations. See Section 4.4 foradditional information.

5. The only required development that is unique to the re-use of retired systems is for circuitryto interface the observatory node instruments to the cable data stream and for shore basedcircuitry to interface the IP data format to the cable data stream format. See Section 4.5 foradditional information.

6. The reliability of in-situ equipment should continue to exhibit telecommunications industryperformance, i.e., 25 years minimum life and probably longer. The reliability of relocated

cable and repeaters should exhibit similar performance, assuming that standardtelecommunications industry care in taken during the recovery and re-lay. The reliability fornew equipment on re-used systems should be similar to that of equipment on new systems ofequivalent configuration. See Section 4.6 for additional information.

7. For equivalent architecture and complexity, re-used cable systems either in-situ or relocated,are almost always less expensive than new cable systems. It is outside the scope of thecommittee, however, to comment on the issue of “equivalent architecture and complexity”.

8. The only security issue unique to cable system re-use is the impact on nearby military cablesduring the recovery of a cable that is being relocated. See Sections 3.5 and 5.5 for additionalinformation.

6.2. RecommendationsThe following recommendations have been made in previous sections of this report.

1. Conduct a careful examination of all terms and conditions in all of the existing licenses andpermits granted to the original cable system owners as well as all applicable laws andtreaties. See Section 5.3 for additional information.

2. Evaluate third person liability costs and indemnification with the insurance carrier of the re-used cable system owner, e.g., IOC. See Section 5.3 for additional information.

3. Procure

- all spare cable and available associated cable hardware (jointing kits, terminationhardware, branching units, etc.),

- all spare repeaters and associated equipment,

- all other spare terminal and repeater electronics and all available test and maintenanceequipment unless time is available to do sufficient system design for re-used systems topermit detailed decisions and

- a complete set of SL280 and SL560 system documentation to protect ability to re-usecable systems until decisions are made.

See Section 5.4 for additional information.

4. Define the test equipment that should be included as part of any retired cable systemprocurement and the required new test equipment that is not unique to the re-use of retiredsystems.

5. Develop other less expensive cable storage capabilities than current commercial approaches,e.g. coastal river barges, inexpensive university and government facility, laboratory or Navy,waterfront space. See Appendix 6 for additional information.

6. Require a detailed failure mode analysis for observatory node equipment and the associatednecessary failure mitigation for both re-used and new systems.

The following recommendations are made in response to the charge to the Committee to make“Recommendations, as appropriate, for near term steps for proceeding”.

7. Establish working groups to

- build upon the work started by IRIS Ocean Cable with respect to the re-use of retired andto be retired cable systems,

- develop a capital and expense investment time line to protect the ability to re-use retiredand to be retired cable systems until decisions can be made and

- develop specific plans for cable re-use for input to the re-use decisions. This last groupshould start with one Pacific Ocean cable and then one Atlantic Ocean cable. Considerstarting this activity at the cable regional observatory workshop in October 2003.

The Committee also makes the following recommendations.

8. Require that any future Requests for Proposals or Announcements of Opportunity related tomechanical and electrical arrangements for the use of repeatered re-used cable systemsheavily weight proposals that are broadly applicable.

9. Examine the procurement of all land and ship based cable handling equipment that maybecome available, e.g., cable haulers, LCEs, deployment drums, cable troughs, A-frames,cranes, gantries and ROVs.

10. Examine the procurement of retired and to be retired cable ships.

11. Initiate discussions with AT&T with respect to potential retirement of third generationundersea lightwave systems e.g., TAT-12/13.

12. Establish contact with the Naval Facilities Engineering Command for advice on possiblemilitary cable opportunities as well as assistance for complying with the security issuesaddressed in Section 5.5. Also stay abreast of all activities in the scientific community.

7. References

Butler, R. 2003. Scientific use of a fiber-optic submarine telecommunications cable systems.

Clark, H. L. 2001. New seafloor observatory networks in support of ocean science research,IEEE Conference Publishing, http://www.coreocean.org/Dev2Go.web?id=232087

Glenn, S.M. and T.D. Dickey. 2003. SCOTS:Scientific Cabled Observatories for Time Series,NSF Ocean Observatories Initiative Workshop Report, Portsmouth, VA., 80 pp.,www.geoprose.com/projects/scots_report.html.

National Ocean Partnership Program. 2001-2002. An Integrated Ocean Observing System: AStrategy for Implementing the First Steps of a U.S. Plan.http://www.coreocean.org/deos/Dev2Go.web?id=220672

National Research Council. 1998. Opportunities in Ocean Sciences: Challenges on the Horizon.National Academy Press, Washington DC. 9 pp.

National Research Council. 2000. Illuminating the Hidden Planet, the Future of SeafloorObservatory Science. National Academy Press, Washington DC. 135 pp.

National Research Council. 2003. Enabling Ocean Research in the 21st Century: Implementationof a Network of Ocean Observatories. In press.

8. Appendices8.1. Appendix 1 – Committee Scope

Optical Submarine Cable Re-Use for Scientific PurposesWith the current downturn in the telecommunications industry, as well as dramatic increases inbandwidth available on the newest generation of fiber optic submarine cables resulting fromsignificant advances in technologies underlying fiber optic communications, many first andsecond generation fiber optic submarine cables are now being retired. There is currently muchdiscussion within the scientific community about the potential scientific resource provided by there-use of these retired cables for seafloor and water column research. The geographic locationand/or relocation of these cables could potentially provide the scientific community with highpower and bandwidth to instrumentation well situated to address high priority science.

Priority science must ultimately drive the need for the establishment of observatory sites usingretired submarine telecommunication cables. There are many technical and economical issuesthat must first be addressed before significant resources are committed to the acquisition and useof these early generation fiber optic cables for scientific purposes. Because of these technicalissues and concerns about feasibility and costs, this committee has been established to provideNSF and the Scientific Community with advice on the following:

- What are the engineering limitations related to the re-use of retired fiber optic cables?- What are the re-engineering/engineering development issues that must be dealt with inorder to re-use the submarine cable systems likely to be retired?- What are the issues related to the power systems associated with these cables? Whatpower would be available at the seafloor for supporting sensors in the seafloor and watercolumn?- What are the issues related to communications protocols and the potential for translatinglegacy technologies to other protocols (e.g. TCP/IP) in use on the Internet.- In what circumstances will the relocation of a cable and the salvage of repeaters be lessexpensive than establishing a new system?- What is the feasibility and approximate associated cost of relocating retired cables?

Three cases should be considered:

• Cable reuse in place• Cable re-use with some relocation but using original shore station• Cable re-use with relocation of the cable and establishment of a new land station.

- What are the liability issues associated with ownership and use?

- How much liability should be incurred in the acceptance of spares related to each of theseretired systems? Should all spares be accepted?

Recommendations, as appropriate, for near term steps for proceeding.

8.2. Appendix 2 – Upcoming Cable Retirements and Decision Dates (Butler, 2003)Cable Retirement Date Decision on Spares Transfer Agreement-in-PrincipleTAT-8 May 2002 Spares lost November 2003

Station Equipment temporarilysaved at IOC request 11/2002

GPT April 10, 2003 June 1, 2003 October 1, 2003TAT-10 June 30, 2003 August 31, 2003 December 31, 2003TAT-11 June 30, 2003 August 31, 2003 December 31, 2003HAW-4 September 30, 2003 December 31, 2003 March 31, 2004TPC-3 September 30, 2003 December 31, 2003 March 31, 2004TAT-9 December 2003 February 2004 June 2004

8.3. Appendix 3 – Hardware DevelopmentNode Connections

A cost-effective, reliable system must be developed for connecting observatories to the cables.The constant-current power system demands that all observatories must be connected in series,such that any observatory malfunction could disrupt the whole cable system unless precautionsare taken. The node connection is critical since failure could disrupt the whole cable system. Aschematic for possible use with a SL280 system is shown below (Figure 6). The nodeconnections (green) would provide power and fiber (blue) connections to observatories (red). Amechanical (power-off) switch in the connection node would be opened by the ROV when anobservatory was connected, allowing power to pass to the observatory.

Figure 6: Potential schematic for a node connection with a SL280 system.

Power Supplies

Power is supplied to the observatories by a voltage drop across the observatory. The observatorysupplies must change the constant-current cable power to constant-voltage supplies required bymost electronics. The supply must also be able to adjust for changes in load as instruments areadded, and as configurations change. The power supply designed for the Hawaii-2 Observatoryperforms these tasks, and a supply for use on the optical cable systems is under development atHawaii. A design review utilizing the expertise available from the telecom industry is neededprior to implementation.

Communications Systems

The figure above shows one possible design for communications with observatories on retiredfirst generation optical cable systems. In this case, a communications circuit consists of a loop

utilizing one of the two pairs of fibers available in the SL cables. Each fiber pair has the capacityto transmit 280 Mb/s, and each could supply two channels of 100 Base T Ethernet data. Sincetwo fiber pairs can be active at a time, the cable capacity would then be 400 Mb/s. Restrictions indata protocol are imposed by the repeaters, which demand a particular data rate and data format(24b-1p). The repeaters themselves accept commands to switch fibers, loop-back fibers, andother tasks, which will be important to the reliability of these systems.

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8.5. Appendix 5 – Cost SpreadsheetCABLE REUSE COST MODEL

Upfront costsDeveloping these costs is beyond the scope of this effort but should includecosts such as the following

Route engineering Additional survey (if necessary) Observing node(s) design, construction & test Shore station lease rates (if shore station exists) Shore station construction costs (for new shore station) Permit maintenance fees (incl. Fishing organizations) Legal fees Right of way fees Cost of backhaul to internet and others

Input ParametersMost Optimistic Most Likely Most

PessimisticCable ship operating day rate $40,000 $40,000 $80,000Cable ship transit day rate $30,000 $40,000 $80,000 $/dayCable ship transit speed 25.9 22.2 22.2 km/hrTime to recover and repair a cable break 1 2 3 daysTime to work around a overlaying cable 1 2 3 daysScience Ship operating day rate $20,000 $20,000 $30,000 $/day

DEOS Cable Re-Use Committee Report page 26 of 3009/15/03

SCENARIO 1: Transit to mid ocean, recover 1500 km of cable, turn and re-lay to a new site, deploy 1observing node at the end of the cable from cable lay vessel

Most Optimistic Most Likely MostPessimistic

Cable Ship Transit distance 2000 2000 2000 kmCable Ship Transit cost $96,525 $150,150 $300,300 $Cable location and recovery time 0.5 0.5 1 daysSplice time 0 0.5 1 daysLocate, recover, splice cost $20,000 $40,000 $160,000 $Length of cable to recover 1500 1500 1500 kmRecovery rate 1.8 1.3 0.9 km/hourExpected number of breaks 1 2 3 eachNumber of overlaying cable crossing 1 2 3 eachRecovery cost $1,468,889 $2,243,077 $6,995,556 $Distance to new shore landing 0 0 0 kmTransit to new shore landing cost $0 $0 $0 $Time to pull cable ashore 0 0 0 daysCost to pull cable ashore $0 $0 $0 $Length of cable to deploy 1500 1500 1500 kmDeployment rate 9.25 7.4 5.55 km/hourDeployment cost $270,270 $337,838 $900,901 $Number of observatory nodes 1 1 1 daysObservatory node installation time 1 1.5 2 daysObservatory node installation cost $40,000 $60,000 $160,000 $Return to port $96,525 $150,150 $300,300 $

TOTAL COST $1,992,209 $2,981,215 $8,817,057 $

DEOS Cable Re-Use Committee Report page 27 of 3009/15/03

SCENARIO 2: Transit to mid ocean, recover 1500 km of cable, transit 1000 nmi to new shore landing,pull cable ashore, re-lay to new site deploy 1 observing node at the end of the cable from the cable ship

Most Optimistic Most Likely MostPessimistic

Cable Ship Transit distance 2000 2000 2000 kmCable Ship Transit cost $96,525 $150,150 $300,300 $Cable location and recovery time 0.5 0.5 1 daysSplice time 0 0.5 1 daysLocate, recover, splice cost $20,000 $40,000 $160,000 $Length of cable to recover 1500 1500 1500 kmRecovery rate 1.8 1.3 0.9 km/hourExpected number of breaks 1 2 3 eachNumber of overlaying cable crossing 1 2 3 eachRecovery cost $1,468,889 $2,243,077 $6,995,556 $Distance to new shore landing 1000 1000 1000 n miTransit to new shore landing cost $64,350 $75,075 $150,150 $Time to pull cable ashore 1 1.5 2 daysCost to pull cable ashore $40,000 $60,000 $160,000 $Length of cable to deploy 1500 1500 1500 kmDeployment rate 9.25 7.4 5.55 km/hourDeployment cost $270,270 $337,838 $900,901 $Number of observatory nodes 1 1 1 daysObservatory node installation time 1 1.5 2 daysObservatory node installation cost $40,000 $60,000 $160,000 $Return to port $96,525 $150,150 $300,300 $

TOTAL COST $2,096,559 $3,116,290 $9,127,207 $

DEOS Cable Re-Use Committee Report page 28 of 3009/15/03

8.6. Appendix 6 – Potentially Available Spare CablesCable Type1 Storage Location Length (km) Storage Required(CuFt) System OwnerSL-DA2 Guam 0.968 93 GPTSL-FBP3 Guam 40.410 1503 GPTSL-FBP Guam 40.425 1504 GPTSL-DA Honolulu 3.826 368 HAW-4SL-FBP Honolulu 3.661 136 HAW-4SL-FBP Honolulu 3.435 128 HAW-4SL-LW4 Honolulu 18.788 306 HAW-4SL-SA5 Honolulu 4.963 325 HAW-4SL-LW Portland 4.671 76 HAW-4SL-LW Portland 5.505 90 HAW-4SL-DA Baltimore 7.455 723 TAT-10SL-SPA6 Baltimore 36.523 1370 TAT-10SL-SPA Baltimore 38.383 1439 TAT-10SL-SPA Baltimore 37.854 1420 TAT-10SL-SPA Baltimore 39.014 1463 TAT-10SL-LWA7 Baltimore 5.12 277 TAT-11SL-LWA Baltimore 9.924 535 TAT-11SL-SPA Baltimore 16.341 613 TAT-11SL-SPA Baltimore 37.559 1409 TAT-11SL-SPA Baltimore 38.945 1460 TAT-11SL-SPA Baltimore 38.509 1444 TAT-11SL-SA Baltimore 10.327 683 TAT-9SL-SPA Baltimore 18.322 687 TAT-9SL-SPA Baltimore 17.66 662 TAT-9SL-SPA Baltimore 38.749 1453 TAT-9SL-SPA Baltimore 18.034 676 TAT-9SL-DA Baltimore 5.704 553 TAT-9SL-LW Honolulu 10.99 179 TPC-3SL-LW Honolulu 10.195 166 TPC-3SL-LW Honolulu 6.191 101 TPC-3SL-LW Honolulu 5.736 93 TPC-3 1 All cables contain 6 fibers2 Double Armor3 Fishbite Protected (Same as SPA)4 Lightweight Deep Water5 Single Armor6 Special Application (Same as FBP)7 Light Wire Armor

DEOS Cable Re-Use Committee Report page 29 of 3009/15/03

SL-DA Honolulu 2.778 267 TPC-3SL-LW Honolulu 27.858 454 TPC-3SL-LW Honolulu 14.062 229 TPC-3SL-LW Honolulu 26.456 431 TPC-3SL-LW Honolulu 5.804 95 TPC-3SL-LW Honolulu 9.705 158 TPC-3SL-LW Honolulu 7.871 128 TPC-3SL-LW Honolulu 12.159 198 TPC-3SL-LW Honolulu 10.052 164 TPC-3SL-SA Honolulu 2.146 141 TPC-3

Note: Possibilities for less expensive cable storage include:

Baltimore Cable – Place the cable pans onto a coastal barge and anchor the barge in an unused corner of the harbor.

Guam Cable – Move the cable pans to a more economical site on the waterfront. If a facility in Guam can't befound, the Jones act requires a US flag ship be used if the cable is to be off loaded at a US port. Such ships rarelycall at Guam and consequently consider using a US flag tug and barge to transport the pans to a US port like NorthTongue Point in Oregon (see below). Alternatively, use a non-US flag ship to transport the cable pans to a non-USport such as Victoria or Vancouver, British Columbia.

Honolulu Cable – The University of Hawaii is currently discussing the possibility of taking over the existing SandIsland cable depot.

Portland Cable – A very large waterfront facility at North Tongue Point (http://www.northtonguepoint.com/)is very well suited to storing many, many pans of cable.

DEOS Cable Re-Use Committee Report page 30 of 3009/15/03

8.7. Appendix 7 – Committee Membership and AcknowledgmentsThe committee members are:

• Dr. Jack Sipress, Chair, AT&T (Retired), Tyco (Retired)• Dr. Fred Duennebier, University of Hawaii• Dr. Robert Gleason, AT&T (Retired), Tyco (Retired)• Mr. Gene Massion, Monterey Bay Aquarium Research Institute• Dr. Peter Mikhalevsky, Science Applications International Corporation

This report was sponsored by the National Science Foundation. Committee support wasprovided by Dr. William Fornes of the Consortium for Oceanographic Research and Education.This committee builds on work done previously by NRC committees, the SCOTS Committee,the DEOS Steering Committee, and by several individuals, particularly Rhett Butler (IRIS), N.Rondorf (SAIC), and Mark Tremblay (Tyco, retired). The committee would also like toacknowledge the contributions of Robert Boone, Jr. (AT&T, retired), Tien Nguyen (Tyco,retired) and William Sirocky (Tyco, retired). Their research and efforts and willingness to sharetheir ideas and information have made our task far easier.