MP14 Barge Salvage SurveyMP14 Barge Salvage Survey

Tuesday, March 31, 2009Tuesday, March 31, 2009Location:Location: 30 01 03.47N 089 54 21.67W,30 01 03.47N 089 54 21.67W, AcergyAcergy ((MichoundMichound Slip) N.O.Slip) N.O.

Description of Casualty: Sunken, Total immersion, DamagedDescription of Casualty: Sunken, Total immersion, DamagedConcrete barge 90Concrete barge 90’’ x 60x 60’’ x 12x 12’’ mainmain--deck displacement hull with eight twodeck displacement hull with eight two--

column concrete bents supporting an upper concrete deck stringercolumn concrete bents supporting an upper concrete deck stringer..New Construction weight: nominally 1105 short tonsNew Construction weight: nominally 1105 short tons

Last known deadLast known dead--weight (taken from 9.5 draft): 1616 short tonsweight (taken from 9.5 draft): 1616 short tons

Orientation of casualty:Orientation of casualty:

•• Reference marks are located at each corner of the main deck withReference marks are located at each corner of the main deck withmudmud--line elevations at corners of barge. Elevation of the waterline elevations at corners of barge. Elevation of the watersurface at time of survey was +1.25surface at time of survey was +1.25’’. Beginning at the South. Beginning at the South--EastEastcorner of the casualtycorner of the casualty

•• (DC(DC--1) elevation was1) elevation was --9.759.75’’ (water depth 11(water depth 11’’) mud) mud--line depth wasline depth was --22.2522.25’’ (water depth 23.5(water depth 23.5’’) moving clock) moving clock--wise to Southwise to South--West CornerWest Corner

•• (DC(DC--2) elevation was2) elevation was --27.7527.75’’ (water depth 29(water depth 29’’), mud), mud--line elevationline elevationwaswas --33.7533.75’’ (water depth 35(water depth 35’’), moving clock), moving clock--wise to Northwise to North--WestWestcornercorner

•• (DC(DC--3) elevation was3) elevation was --37.7537.75’’ (water depth 39(water depth 39’’) and mud) and mud--linelineelevation waselevation was --36.7536.75’’ (water depth 38(water depth 38’’). Moving clock). Moving clock--wise to Northwise to North--East cornerEast corner

•• (DC(DC--4) elevation was4) elevation was --19.7519.75’’ (water depth 21(water depth 21’’) and mud) and mud--linelineelevation waselevation was --28.25 (water depth 29.528.25 (water depth 29.5’’).).

SideSide--Scan Sonar ImagesScan Sonar Images

DC-2

DC-1

DC-3

Note openhatch at DC-3and excavatedbottom profile

DC-2

DC-1

Three dimensional drawing shows present mud-linein relationship to casualty interior

Details thre dimensional re

Presents 3-dimensional relationship of mud-line to casualty

Obstruction Beneath CasualtyObstruction Beneath Casualty

•• The barges was then referenced in fifteen feet increments beginnThe barges was then referenced in fifteen feet increments beginning at DCing at DC--1 to DC1 to DC--44(the shore(the shore--ward 90ward 90’’ side) and began jetting 70side) and began jetting 70’’ long sections of 2long sections of 2”” diameter conduitdiameter conduitbeneath the barge to determine if jetting lifting bands beneathbeneath the barge to determine if jetting lifting bands beneath the casualty would bethe casualty would bea viable option. From corner DC1 (South to North):a viable option. From corner DC1 (South to North):

•• 0+150+15’’: Encountered solid obstruction at 37: Encountered solid obstruction at 37’’ penetration. Divers attempted to adjustpenetration. Divers attempted to adjustangle slightly Southward and encountered solid obstruction at 40angle slightly Southward and encountered solid obstruction at 40’’ penetration. A thirdpenetration. A thirdconduit was attempted at a greater angle and conduit deflected oconduit was attempted at a greater angle and conduit deflected off solid and exitedff solid and exitedthe front of casualty 15the front of casualty 15’’ from corner rather than exiting the opposing side of thefrom corner rather than exiting the opposing side of thecasualty.casualty.

•• 0+30: Divers inserted conduit and encountered solid obstruction0+30: Divers inserted conduit and encountered solid obstruction at 32at 32’’ penetration. Apenetration. Asecond attempt was made with similar results.second attempt was made with similar results.

•• 0+450+45’’ (center(center--line): Divers encountered solid obstruction at 26line): Divers encountered solid obstruction at 26’’ penetration.penetration.•• 0+600+60’’: divers encountered solid obstruction at 20: divers encountered solid obstruction at 20’’ penetration.penetration.•• 0+750+75’’: divers encountered solid obstruction at 12: divers encountered solid obstruction at 12’’ penetration.penetration.

•• After a consultation with WayneAfter a consultation with Wayne FillingameFillingame ((AcergyAcergy), it was noted that a previous), it was noted that a previoustenant had disposed of two concrete bridge deck sections in thetenant had disposed of two concrete bridge deck sections in the vicinity of thevicinity of thecasualty and that the casualty is resting atop of one or both ofcasualty and that the casualty is resting atop of one or both of them, therethem, there--bybyprecluding the use of lifting bands beneath the casualty by convprecluding the use of lifting bands beneath the casualty by conventional means.entional means.

Internal InspectionInternal Inspection

•• Divers entered the casualty at an open access point located in tDivers entered the casualty at an open access point located in the Northhe North--West quadrant (DCWest quadrant (DC--3, lowest elevation) and determined a depth of3, lowest elevation) and determined a depth ofsiltation average of 6.75siltation average of 6.75’’ inside that quadrant. Since the majority of theinside that quadrant. Since the majority of themainmain--deck is beneath the natural muddeck is beneath the natural mud--line, this was not unexpectedline, this was not unexpectedinformation. Divers deployed an airinformation. Divers deployed an air--lift to remove mud from inside thislift to remove mud from inside thisquadrant to survey potential damage to the sidequadrant to survey potential damage to the side--walls and deck, Fourwalls and deck, Fourprimary areas of damage were noted, including:primary areas of damage were noted, including:

•• North Side wall hole nominally 12North Side wall hole nominally 12”” x undetermined lengthx undetermined length•• West Side wall and deck has apparent collision damage that is deWest Side wall and deck has apparent collision damage that is detailed intailed in

attached sketch, measuring:attached sketch, measuring:–– Deck has hole extending seven feet inboard by fourteen feet longDeck has hole extending seven feet inboard by fourteen feet long–– SideSide--wall has hole and fractured area six feet by fourteen feetwall has hole and fractured area six feet by fourteen feet

•• Near centerline west hatch (sealed by salvage patch) has deckNear centerline west hatch (sealed by salvage patch) has decksurrounding it heavily fractured and holed by apparent compressesurrounding it heavily fractured and holed by apparent compressed aird air

•• NorthNorth--west deck shows heavy spall and fractured concrete with exposedwest deck shows heavy spall and fractured concrete with exposedrebarsrebars at juncture to sideat juncture to side--wall and indications of deck separation.wall and indications of deck separation.

•• All mud removed from inside this quadrant by airAll mud removed from inside this quadrant by air--lifting was replenishedlifting was replenishedthrough deck and sidethrough deck and side--wall damage in under 12 hours.wall damage in under 12 hours.

Areas of deckseparation noted

DC-4DC-3

Note depth of casualtybelow existing bottomcontour at corner DC-3

Ground Reaction ForcesGround Reaction Forces

•• The DCThe DC--3 quadrant is resting in a depression created by dredging during3 quadrant is resting in a depression created by dredging duringthe previous salvage attempt with the natural mudthe previous salvage attempt with the natural mud--line elevation slopedline elevation slopedfromfrom --2727’’ to the reference point DCto the reference point DC--3 elevation of3 elevation of --37.75. This is a critical37.75. This is a criticalcomponent because, without this dredged depression, most of thecomponent because, without this dredged depression, most of the bargebargewould be completely below the mudwould be completely below the mud--line with the deepest point being 10line with the deepest point being 10’’below the mudbelow the mud--line at DCline at DC--3. The initial dredging depression created a mud3. The initial dredging depression created a mud--line elevation lower than the deck surface of the barge but hasline elevation lower than the deck surface of the barge but hassubsequently slumped material back into the depression to an elesubsequently slumped material back into the depression to an elevationvationslightly covering the DCslightly covering the DC--3 quadrant and consistently replacing any3 quadrant and consistently replacing anysediments removed from inside the casualty by ingress through lsediments removed from inside the casualty by ingress through largeargedamage openings in the Northdamage openings in the North--west sidewest side--wall, Northwall, North--West Deck, WestWest Deck, Westcentercenter--line deck opening, and the North Sideline deck opening, and the North Side--wall (all beneath the existingwall (all beneath the existingmudmud--line except the centerline except the center--line access).line access).

•• Actual ground reaction is extrapolated at 88 pounds per square fActual ground reaction is extrapolated at 88 pounds per square ft. acrosst. acrossthe bottom of the casualty based on laboratory results of samplethe bottom of the casualty based on laboratory results of samples takens takenfrom each of the four corners. Overcoming the reaction (soil sufrom each of the four corners. Overcoming the reaction (soil suction) forction) forinitial movement will require an additional force of 237.6 Tonsinitial movement will require an additional force of 237.6 Tons above totalabove totaldeaddead--weight. This reaction component will go away once initial movemweight. This reaction component will go away once initial movemententis achieved.is achieved.

Note open hatches in deckand sediment above deckat North-west corner

DC-4

DC-3

SummarySummary

•• This casualty is immersed on a descending mud bank near parallelThis casualty is immersed on a descending mud bank near parallel to theto theshoreshore--line with a 14line with a 14ºº Port to starboard list and a 16Port to starboard list and a 16ºº diagonal (port bow todiagonal (port bow tostarboard stern) trim. Average depth of mud surrounding the casustarboard stern) trim. Average depth of mud surrounding the casualty isalty is5.55.5’’ with corner DCwith corner DC--1 being 12.51 being 12.5’’ above the mudabove the mud--line and corner DCline and corner DC--33being 1being 1’’ below the mudbelow the mud--line. Most of the DCline. Most of the DC--3 quadrant (the only quadrant3 quadrant (the only quadrantpenetrated during the inspection) is filled with sediment to anpenetrated during the inspection) is filled with sediment to anapproximate level surface, estimated at minimally1200 cubic yardapproximate level surface, estimated at minimally1200 cubic yards, ifs, ifconsistent throughconsistent through--out the plane of the entire barge interior (we wouldout the plane of the entire barge interior (we wouldassume this to be so).assume this to be so).

•• Quadrant DCQuadrant DC--3 is heavily damaged on both side3 is heavily damaged on both side--walls and deck and is notwalls and deck and is notcapable of supporting the forces anticipated to gain buoyancy ancapable of supporting the forces anticipated to gain buoyancy and willd willhave to be carefully planned by weight and dimension, to maintahave to be carefully planned by weight and dimension, to maintaininstructural integrity necessary to lift.structural integrity necessary to lift.

•• Solid obstruction beneath the barge is probably a remnant bridgeSolid obstruction beneath the barge is probably a remnant bridge deckdecksection (per Waynesection (per Wayne FillingameFillingame,, AcergyAcergy). This obstruction eliminates the). This obstruction eliminates thepossibility of jetting lifting bands beneath the casualty by conpossibility of jetting lifting bands beneath the casualty by conventionalventionalmethods. There remains an option of directional boring beneath tmethods. There remains an option of directional boring beneath thehecasualty to insert rigging but this method is both costly and incasualty to insert rigging but this method is both costly and inefficient andefficient andseverely limits load distribution of the rigging slings by size.severely limits load distribution of the rigging slings by size.

Salvage/Removal OptionsSalvage/Removal Options

350 Ton Chain Pullers

Wreck in PlaceWreck in Place

•• Due to the amount of structural steel (Due to the amount of structural steel (rebarsrebars) in) inthe casualty and the depth and consistency ofthe casualty and the depth and consistency ofthe sediments surrounding the casualty,the sediments surrounding the casualty,demolition by breaking would be virtuallydemolition by breaking would be virtuallyimpossible to guarantee substantial removalimpossible to guarantee substantial removalwithout permitting for bucket dredging. Previouswithout permitting for bucket dredging. Previousremoval attempts by Pearl River Navigation of aremoval attempts by Pearl River Navigation of asimilar concrete barge near this location weresimilar concrete barge near this location wereeventually abandoned after removing aneventually abandoned after removing anestimated 30estimated 30--40% of the casualty.40% of the casualty.

RefloatRefloat

•• A previous salvage attempt of this casualty conducted by OffshorA previous salvage attempt of this casualty conducted by Offshore Marinee MarineContractors, utilizing pump capacity in excess of 15,000Contractors, utilizing pump capacity in excess of 15,000 gpmgpm (per Steve Pemberton,(per Steve Pemberton,owner of Fastowner of Fast--flow Pumps Inc.) combined with compressed air injection rather tflow Pumps Inc.) combined with compressed air injection rather thanhanambient air intake, resulted in a partial refloat of one end ofambient air intake, resulted in a partial refloat of one end of the casualty before airthe casualty before airpressure fractured numerous areas of deck surface and separatedpressure fractured numerous areas of deck surface and separated portions of theportions of thedeck from the sidedeck from the side--walls. This is in evidence by heavy spall and exposedwalls. This is in evidence by heavy spall and exposed rebarsrebars at theat thejuncture of the deck to the sidejuncture of the deck to the side--walls throughwalls through--out the casualty and by a severelyout the casualty and by a severelydamaged area of the deck surrounding the Southern end of the cendamaged area of the deck surrounding the Southern end of the centerline deckterline deckaccess 3access 3’’ x 5x 5’’ that had been sealed by a salvage patch.that had been sealed by a salvage patch.

•• While it may be possible to patch this casualty to a point whereWhile it may be possible to patch this casualty to a point where a refloat could bea refloat could beachieved, several factors need to be accounted:achieved, several factors need to be accounted:

•• Substantial ground reaction from the present attitude (beneath tSubstantial ground reaction from the present attitude (beneath the existing mudhe existing mud--line) will require a considerable amount of dredging around theline) will require a considerable amount of dredging around the casualty and somecasualty and somemeans of slowing remeans of slowing re--ingress for the duration of the salvage operations.ingress for the duration of the salvage operations.

•• Near complete removal of all sediment inside the casualty will bNear complete removal of all sediment inside the casualty will be required to reducee required to reduceboth the static and dynamic loads prior to refloat.both the static and dynamic loads prior to refloat.

•• There is heavy potential of severe damage as yet unidentified whThere is heavy potential of severe damage as yet unidentified which may include theich may include thebottom of the casualty that would eliminate the possibility of rbottom of the casualty that would eliminate the possibility of refloat.efloat.

•• With these factors in mind, I would estimate less than a 30% proWith these factors in mind, I would estimate less than a 30% probability ofbability ofsuccessful salvage by conventional refloat.successful salvage by conventional refloat.

Intact LiftIntact Lift

•• Lifting the casualty intact is a viable option with a moderate tLifting the casualty intact is a viable option with a moderate to high probability ofo high probability ofsuccess but would entail several factors:success but would entail several factors:

•• Since the casualty is resting upon some type of solid structure,Since the casualty is resting upon some type of solid structure, the possibility ofthe possibility oflifting from beneath the barge with metal straps is not a viablelifting from beneath the barge with metal straps is not a viable or cost effectiveor cost effectiveoption.option.

•• While the static load, as constructed, should be only around 700While the static load, as constructed, should be only around 700--800 tons (while800 tons (whileimmersed), The dynamic load would include the displaced weight oimmersed), The dynamic load would include the displaced weight of nominally 1200f nominally 1200cubic yards of sediment inside the barge (648 tons displaced weicubic yards of sediment inside the barge (648 tons displaced weight), and a groundght), and a groundreaction force of nominally 237.6 tons.reaction force of nominally 237.6 tons.

–– Sediments inside the barge can be removed by divers and most ofSediments inside the barge can be removed by divers and most of the points ofthe points ofingress arrested but will require substantial time and costs foringress arrested but will require substantial time and costs for penetration divingpenetration divingoperations.operations.

–– Ground reaction forces can be greatly reduced by dredging but maGround reaction forces can be greatly reduced by dredging but may requirey requirepermitting and other environmental costs and timepermitting and other environmental costs and time--lines.lines.

•• Lifting points on the casualty will have to be distributed alongLifting points on the casualty will have to be distributed along the sidethe side--wallswallsequilaterally to allow for a maximum tension force of 200 tons pequilaterally to allow for a maximum tension force of 200 tons per leg and woulder leg and wouldrequire a minimum of ten chainrequire a minimum of ten chain--pullers to guarantee a high probability of successpullers to guarantee a high probability of success(see Lifting(see Lifting--pin diagram).pin diagram).

–– Would require four barges to distribute the loads safelyWould require four barges to distribute the loads safely–– Equilateral distribution of the load may be affected by concreteEquilateral distribution of the load may be affected by concrete damage as yetdamage as yet

undiscovered on the casualtyundiscovered on the casualty•• Final disposition of the casualty would be limited to reefing orFinal disposition of the casualty would be limited to reefing or releasing the load toreleasing the load to

another location until patches could be installed in damaged areanother location until patches could be installed in damaged areas and lifting pointas and lifting pointaccess holes to allow the barge to be refloated.access holes to allow the barge to be refloated.

Dragging to ShoreDragging to Shore

•• Dragging the casualty to shore utilizing chainDragging the casualty to shore utilizing chain--pullers, either intact or in sections, ispullers, either intact or in sections, isalso a viable option with the following considerations:also a viable option with the following considerations:

•• Shore soil compaction factored to determine the number of MantaShore soil compaction factored to determine the number of Manta--anchors necessaryanchors necessaryto deadto dead--man the pullersman the pullers

•• Installation of slideInstallation of slide--beams beneath the leading edge of the casualty to insure a lessebeams beneath the leading edge of the casualty to insure a lesserrdegree of friction as well as to preclude the possibility of thedegree of friction as well as to preclude the possibility of the casualtycasualty ““bullbull--dozingdozing””into the strata while being pulledinto the strata while being pulled

•• It may be possible toIt may be possible to ““ChokeChoke”” the ends of the casualty with heavy chain by dredgingthe ends of the casualty with heavy chain by dredgingbut will need to be reinforced to prevent the chains from breakibut will need to be reinforced to prevent the chains from breaking into the concrete.ng into the concrete.

•• Ground reaction forces still have to be taken into account whenGround reaction forces still have to be taken into account when estimating theestimating thenumber of pullers needed to drag the load to shore. Should thisnumber of pullers needed to drag the load to shore. Should this factor be in excess offactor be in excess ofthe holding force of the mantathe holding force of the manta--anchors, sectioning of the casualty would be requiredanchors, sectioning of the casualty would be requiredto reduce the weight of the load.to reduce the weight of the load.

•• The casualty will be heavily damaged, probably beyond recovery,The casualty will be heavily damaged, probably beyond recovery, by this method andby this method andwould require complete demolition and removal by truck or barge.would require complete demolition and removal by truck or barge.

•• While this method is a viable option with a very high probabilitWhile this method is a viable option with a very high probability of success, the timey of success, the time--line is not predictable enough to allow as an option other thanline is not predictable enough to allow as an option other than under aunder a ““Time andTime andMaterialsMaterials”” agreement.agreement.

Sectional RemovalSectional Removal•• This method of removal has the highest probability of success ofThis method of removal has the highest probability of success of all the options considered with theall the options considered with the

additional advantage of moderately predictable costs and timeadditional advantage of moderately predictable costs and time--lines. The casualty would be crosslines. The casualty would be cross--sectioned into five roughly proportional sized sections (60sectioned into five roughly proportional sized sections (60’’ x 18x 18’’) utilizing a) utilizing a ““toptop--downdown”” diamond wirediamond wiresaw (see attached sketch ).saw (see attached sketch ).

•• An airAn air--lift would be deployed by crane to excavate access at each pointlift would be deployed by crane to excavate access at each point to be sectioned to allow theto be sectioned to allow thediver to attach each turning sheave to the sidediver to attach each turning sheave to the side--wall of the casualty with the sheave extending below thewall of the casualty with the sheave extending below thebottom edge of the casualty. The sheave plates are attached utilbottom edge of the casualty. The sheave plates are attached utilizing four (4) 3/8izing four (4) 3/8”” grade eight studgrade eight studbolts driven into the sidebolts driven into the side--wall with an underwater powderwall with an underwater powder--actuated fastener tool. The diamond wire isactuated fastener tool. The diamond wire isthen threaded from the work platform barge through the outside othen threaded from the work platform barge through the outside of one sheave, over the top of thef one sheave, over the top of thecasualty and down to the second sheave and back to the saw unitcasualty and down to the second sheave and back to the saw unit located on the work platform barge.located on the work platform barge.

•• Each end (sideEach end (side--wall) of a section will require two 6.25wall) of a section will require two 6.25”” diameter corediameter core--borings to act as a receiver for theborings to act as a receiver for thelifting pins (see attached lifting pin drawing). Core drill is hlifting pins (see attached lifting pin drawing). Core drill is hydraulically operated and requires a singleydraulically operated and requires a single5/85/8”” x 6x 6”” RedRed--head to attach to the sidehead to attach to the side--wall. Three inch chain will be shackled to each lifting pin andwall. Three inch chain will be shackled to each lifting pin andpassed to a 250 ton hydraulic chain puller, mounted on a barge.passed to a 250 ton hydraulic chain puller, mounted on a barge. Each piece will then be lifted betweenEach piece will then be lifted betweenthe two staging barges and towed to a prethe two staging barges and towed to a pre--determined place for disposal. There are several advantagesdetermined place for disposal. There are several advantagesto this method of removal:to this method of removal:

•• Requires only two inland work barges (one with small crane) to aRequires only two inland work barges (one with small crane) to assist with operations.ssist with operations.•• Requires minimal shore staging of operationsRequires minimal shore staging of operations•• Requires minimal dredging or permitsRequires minimal dredging or permits•• Requires only four (4) chainRequires only four (4) chain--pullers, lifting pins, and chain shotspullers, lifting pins, and chain shots•• Greatly reduced ground reaction forcesGreatly reduced ground reaction forces

–– Reduced surface areaReduced surface area–– Renders interior sediments a means of egressRenders interior sediments a means of egress

•• Offers increased disposal optionsOffers increased disposal options•• Engineering data supports load bearing design of lifting pins anEngineering data supports load bearing design of lifting pins and attachments.d attachments.

AppendicesAppendices

•• Diagram of Lifting PinDiagram of Lifting Pin

•• 200 Ton Chain Puller200 Ton Chain Puller

•• 350 Ton Chain350 Ton Chain--pullerpuller

•• Diamond WireDiamond Wire--sawsaw

•• Hydraulic Pile CutterHydraulic Pile Cutter

•• Diamond Wire Routing DiagramDiamond Wire Routing Diagram

250 Ton Chain250 Ton Chain--PullerPuller

Diamond WireDiamond Wire--sawsaw