Update by Capt. Bert Marsh
Director of Ehime Maru Recovery Operation ocean engineering
U.S. Pacific Fleet Public Affairs
Sept. 7, 2001
"As was just mentioned, my name is Bert Marsh, I'm the Supervisor of Salvage. For many of you that were here before, I talked about my background a little bit, but just to remind the ones that weren't here before. I work out of the Naval Sea Systems Command in Washington, D.C. I've been involved with the Ehime Maru recovery effort basically since early February, shortly after she went down. I directed the operation to come out and do the initial search for her. After we found her, I then went back and went through the feasibility study. And at that point we decided we believed we could raise the Ehime Maru. From that time on basically I've been intimately involved in the process of getting all the equipment here, all the logistics, and now I'm out on site. As was just mentioned, I've been on the Rockwater 2 since she arrived, and been out on the site directing from the Navy side.
What I'd like to do first is report back to you that the entire group of people out there, which is a crew of international experts in salvage and the structural side, remain fully committed to the recovery of the Ehime Maru. Lifting her from where she's currently at and bringing her into the shallow area where, as you've already met the other team of divers who will be doing the actual recovery.
We've had a couple of small issues, and where we're going has slightly changed or modified our plan. It's really an evolution of our plan from that standpoint. That's really what I'm going to show you.
Our previous efforts talked about lifting the stern and passing messenger wires. The messenger wires would be used to pass the lifting straps or plates -- they're actual plates that have wire backups to them.
Where we're at right now is we're in a position where we can and are in fact doing right now, passing the after strap into position at Frame 15. So we have gained to that point.
As a result of our efforts, however, what we've ended up with, we actually lifted the vessel for a total of almost 40 hours. In that effort, as I say, we were able to get the after messenger wire in position, but we were not able to get a messenger wire passed forward.
So her current position... To clarify messenger wires. This messenger wire, as I'll show on the next slide, is already in position, and we're currently getting the stern plate ready to put into position.
As a result of lifting the vessel for, as I said, in excess of 40 hours, we have essentially changed her attitude. As she sits currently out on the sea bottom right now, what you'll see is she is up by the stern. We had this messenger wire passed and the Rockwater 2 is on-site right now and will be placing a lifting plate at Frame 15. I'm going to show you that on the next one.
Her rudder is 22 feet, a little over six meters, off the bottom which makes it simple as far as passing the after strap.
The problem we're presented with now is that by lifting her and maintaining her up, we have in fact put Frame 61, which is where we want to put the other messenger, partially in the mud, so we have to overcome that. What we're going to do... Well, go back a second here.
What this really shows is a couple of things. One of those is that the back, that the vessel will now sustain itself in this position, that's caused by two things, or tells us two things. One of those is that we have more strength in the bow area than we initially anticipated.
As I talked to you about the feasibility study, when we conducted that feasibility study we were looking at initial photographs of the vessel taken by an ROV back in February that showed that there was some damage to the side shell in this area. With that we did our calculations all based for strength of the vessel, essentially the bow of the vessel, we did those calculations all based on assuming that the side shells were bad and possibly the deck above it was bad, would not take any load.
In fact because we've been able to lift her or maintain her in that angle for so long, we now believe that we have more strength in the bow area, which is why the Admiral in his comments yesterday said we were more confident in our ability to ultimately lift the vessel and transport her.
Where we stand right now, as I said, the Rockwater 2 is on site. She is in the process of passing this after lifting plate into position. That lifting plate actually is a steel plate. It has wires underneath it as reinforcements, and that will be at Frame 15.
You see a small wire strap right there. With the vessel in this attitude we have to have a retaining strap that holds that lifting strap in place, keeps the lifting strap from sliding down the vessel.
At the same time that we are placing this, we're also going up to the bow area with our ROVs and starting the process of dredging out the bow area so that we can get at what's called the anchor hawse pipes. Those are what we're going to use to lift the bow of the Ehime Maru in order to get the forward strap in.
Once we have dredged the area of the bow in order to be able to get at the anchors and actually cut the anchor chain with the ROVs, we will then recover the anchors either back onto the Rockwater 2 or we'll place them onto the Ehime Maru, one of the two. So that they will be recovered.
Once they are out of the way, though, we will be rigging this sling arrangement that we'll use to lift the bow of the Ehime Maru. That will allow us to place the forward strap into position. It will go on here in a couple of seconds and it will become a little more obvious how we're going to do that.
What we are doing is taking advantage of the previous arrangements we had made as far as a lifting frame are concerned. We designed the lower lifting frame which is this part in green to be buoyant, meaning that it will in fact float. These weights right here, these blue pieces, are clumps that actually hold that down into position. We will take advantage of that buoyancy when we actually transfer a single lifting point out to the bow.
The lifting sling I showed you previously has a fitting on it, a specialized fitting called a delmar fitting. That is used to make a connection in a deep sea situation where the ROV has to make the connection. We're talking capabilities, the delmars will hold in excess of 300-400 tons easily. So it's very massive piece of equipment. They're designed specifically around the idea to make it easy for an ROV to make that connection up underwater. We've actually made that connection several times in our placing of the stern strap area.
So we will be transferring from what, this is called a delmar connection -- female side and the male side, we will be transferring over and actually picking up the bow using what we've already designed. So the process really is an evolutionary one.
We've modified our previous process using the equipment we have. Obviously we had to sit down and do all the engineering calculations.
I mentioned also that we have two members, two Japanese individuals on board who are structural experts. One of them, Dr. Fuji, is actually from the building yard, Kodashiba. He has evaluated our plan for us. In fact he advised us specifically in how we would design these plates. Those plates essentially are called backing plates. The size of those plates determine where you distribute the load as you're picking something up. If you're trying to pick from a single point, you can cause failure there, but if you spread that load out, so the design of those plates was something that in fact Dr. Fuji and Mr. Takamoto helped us with.
Once that's done we will then be in a configuration where we have a single lifting line. This is actually one of our linear winches coming down to lift the bow. We'll have a doubled up linear winch on the stern. We will be pulling from the hawse pipe area, lifting the bow up, lifting the stern. Initially it will be to lift the bow. As you saw, her attitude is like this. We will initially start lifting with the bow. As she starts to come up we will start picking up loads in the stern area. At that point we will start lifting on the stern.
The entire purpose of this is to get it out of the hole that she's currently in so that the bow is open and acceptable to pass the actual permanent forward lifting strap.
As the bow line that you saw here is depicted here, it's really a temporary measure in order to be able to get the bow up far enough so that we can pass the permanent lifting strap into place. That process will mean that we will ultimately pull up on the bow once we... We're going to move her out of the hole she's in, set her in a level part of the sea bed close to where she's at -- we're not going to move her very far. Then we will lift the bow again and place that forward lifting plate.
The rationale for picking it up twice is very simple. That forward lifting plate has to be exactly positioned. We have to put it in the right orientation perpendicular to the hull and at the right position as far as the frame spacing is concerned.
So what we will do is set her down, put in place clump weights on either side of the Ehime Maru. This is part of the original plan. Those clump weights will be used to guide that plate through. But they will be put down in precise locations. One clump weight allows you to pull with the crane; the other clump weight actually allows you to have a backing strap that helps you position it exactly where you want to.
That's the process that will go on. We'll go ahead and put this sling in place, then we will set it back down.
At that point we'll be ready to disconnect the bow. Rockwater 2 will then proceed back into the shallow water area where we will re-rig this top frame. If you noted in the earlier pictures, we were talking that we were actually rigged correctly in the stern one for the after part of the top frame with the double wire. We now have to come back into port. The shivs right there, those [shivs], you saw them on the barge earlier. Those shivs are about two times the size of a man from that standpoint, so they have to be handled very... They're very difficult to handle. So we will be pulling back into the shallow water area. We will actually suspend this beam below the Rockwater and then proceed back out to the site.
At that point we're back into our planned evolution of bringing down the top frame into the bottom frame.
Now we have confidence in the fact that we can move the vessel that short distance with the bow because we have been able to lift her and maintain her up using what is called the dynamic positioning system on the Rockwater 2. What that means is, it is a system that takes input from the GPS system, the satellite up above. It takes that into consideration as to figuring out where the ship is on the ocean. It also reads wind effects on the ship, the current effects on the ship. Those are all put into a computer. The computer turns it around a little bit, and the next thing you know the thrusters are acting to null out or cancel out the effects of the wind and the current.
What we've actually been able to do in this situation is with the dynamic positioning system of the Rockwater, while we had it lifted for almost 40 hours, we were able to maintain position. So we have added another variable to the dynamic positioning system. You don't normally end up with a dynamic positioning system operating while you are essentially moored in 2000 foot of water which is what we were when we were tied into the Ehime Maru.
So we're confident that when we lift we'll be able to safely move her over, set her down on a level portion of the sea bed close to where she's at, then relift the bow just enough to be able to pass the forward strap. The reason we're doing that is to have those... Those are the permanent lifting arrangements. Those are what will be used to both lift her, transport her into the shallow water site. They remain with her throughout the time the divers are conducting their searches. And at that point basically they will be used again to lift the vessel and take her to her deep water site. So that's the permanent arrangement.
What we're doing is a temporary arrangement of lifting the bow enough to get it out of the mud so that we can pass that strap and then move to the beach.
With that, I think that's about all I have. I'll go ahead and take questions for about 15, 20 minutes if you'd like.
Q: How many (inaudible) new (inaudible), how many (inaudible) new vessel?
Marsh: We have incurred some additional timeframe in the fact that we have to do some redredging. That shouldn't be a major delay. To try to get too specific with you, I really can't do that right now.
We have purposely described this event as a milestone-driven event rather than a schedule-driven event, and we need to stay at that pace from that standpoint.
We have safety as our paramount concern out there, so weather effects and other things can fall into it, but trying to give you an exact date is really a little too premature on my side.
What we will do is inform you as we reach the major milestones.
Our next major milestone will be when we have dredged and are ready to lift the bow
Q: Given that you had (inaudible), are you able to give us, I know this might be difficult, a kind of rough percentage, a success rate (inaudible)?
Marsh: This remains a very difficult operation. I don't mean to make it appear like it's just simple, we just switched plans and we can move on from there. However, we do have flexibility in our plans and that's allowed us to move on to this method where we are, because that, as I mentioned, the top or bottom lifting frame is buoyant, if that hadn't been we would have a major problem on our hands. But we don't from that standpoint.
So I still remain very, very confident. I think we will lift here. I don't really want to change the numbers from that standpoint because...
What we've learned is a major factor. We've learned that the bow is much stronger. We've proved that, actually. You make assumptions when you do your engineering based on what you can see, and you always engineer from a conservative standpoint. If you look at any of the rigging or anything else we have out there, we are normally putting in safety factors. That's part of an engineering design.
So we will continue with what we've got right now.
Q: What obstruction did you fine at Frame 41 that forced you to make the switch?
Marsh: Basically when we lifted, in the first diagram, we had it up far enough that we felt that we could run a wire through, but we in fact caught repeatedly in the Frame 41 area. My estimate would be that that may be part of the keel of the ship, of the Ehime Maru.
Q: How are these recent modifications affecting the budget for this operation?
Marsh: When you, if you go back and look at the initial estimates, we labeled them just as that, as initial estimates, based on our assumptions of how long we would be here. So we will reevaluate as we go.
I don't know exactly how long it's going to add to the process yet. I can't answer you in real dollar...
Q: ...costing more than $40 million?
Marsh: There's that possibility. I can't give you any specific numbers right now.
Q: I had a question on the dredging. Is the dredging to free up the anchor holes? I got the impression...
Marsh: No, the dredging, as you mentioned, is in fact designed to get ourselves in a position where we can rig the lifting sling up in the bow, which means we have to get at the anchor hawse pipes. They are currently buried in the mud.
Now what we are doing is we have the capability to dredge with the ROVs as they are set up. They basically use the impellers on the ROVs to suck the silt away. But that's inefficient, so we are flying in from the mainland some extra pumps. I didn't mention it in here, but one of the reasons we're confident in what we're doing is we used a piece of gear we call the hydraulic power unit and that was very effective when we were doing the coil tube drilling effort.
We proved to ourselves that we were capable of making that up, those hydraulic fittings, at 2,000 feet safely, and the pumps all worked perfectly from that standpoint for the coil tube drilling. So we think we can do the same thing, lower the hydraulic power unit down through what's called a moon pool on the ship itself. She has holes in her deck that allow us to lower things. We will lower down the HPU, the hydraulic power unit, to the bottom, connect it up to some dredge pumps that are coming in, being flown in from the mainland, and that will increase the speed of the dredging operation.
Q: How much (inaudible) is there? The (inaudible)?
Marsh: As the picture depicts, the mud line is just about even with the focsle. However what you have is, somebody was asking me this question earlier, as you look at it through the ROV, depending on the angle you look at it, the ROV could be up here looking or it could be sitting down here. What you see is it's mounded up a little bit on the sides, but when you get in close you find out that this is pretty accurate. That you're only talking a meter, meter and a half of clearance right there, which means that the anchors which are down in here, we can't get at right now.
Q: How deep are the anchors them from the top? Do you know how deep they are?
Marsh: I don't know that answer off the top of my head. I'll have somebody get back to you with them.
Q: Can you give us your best estimate of what day you think you'll be able to lift the ship again? And you gave yourself a two month window when this process began because of weather considerations. Where does that stand?
Marsh: As I mentioned, we're looking at this as a milestone event, rather than laying out a schedule and saying if I'm not meeting that schedule I have a problem.
We will report as we get close to those milestones. No, I can't give you a specific date for that just yet. It depends on how long the dredging takes and how long the connection to the bow takes. So we'll let you know when we're getting close and advise everybody.
Part of the environmental assessment was that we advise whenever we move the vessel herself, so we will be advising the public basically when we get into that position again.
Q: What happens if this method fails?
Marsh: We try to always have something in the back pocket to step on to something else. There are multiple variables that you have to deal with.
Up to now we've been in a position where we've been able to move on, first reassess where we're at, and then move on to another method if necessary. It's really evolution. So if we have a problem, I think we will be able to evolve into another solution for it.
The team out there is really a very determined group. It's become a real challenge to them. And I don't see anybody giving up, and I don't plan to.
Q: Why do you think the stern lifting strap failed and what makes you think that the lifting plate is strong enough to hold the ship?
Marsh: The difference being, if you'd go to the first slide, I'll show you some differences there in the way that they are loaded, is what it boils down to.
As we used those straps initially to lift the stern, what you have happening here is you purposely are putting an angle on the vessel. As that angle increases, what happens is this strap right here comes up against this post so it actually deforms. That deformation means that it is not as strong as it normally would be.
In the situation that we found ourselves in, was basically that we lifted the first time without reinforcement wires behind, and in that case we actually parted the straps. It was a controlled evolution. Nothing was harmed on the Ehime Maru or anything else. We made the decision to lift her. We actually had her up for eight hours. At that point we thought we had passed the wires forward and in fact they were not as far forward as we thought.
You must understand that while we have the vessel up in the air, she is moving very slightly, but that is creating a continual dust cloud. Silt cloud. It's not dust down there, but it's silt. That is spilling out continuously. So the ROVs in their working around there basically lose visibility.
I gave an analogy awhile back about the ROVs trying to do something down there as take one eye and cover it and work with your hands, but remember you have no feeling whatever with the ROVs. So when you lose visibility with that one eye, you can't tell whether you have ahold of anything at all. You have no idea. So you have to wait for the visibility to clear.
So that visibility issue caused us the difficulty that first caused us to set it down the first time, thinking that we had actually passed the messenger far enough forward. We were confident with the after one that in fact it was in the position that we wanted it. The first time we lifted it we got that after stern wire messenger in the position we wanted it.
That's sort of a long-winded answer, but when we pass these underneath they will not be coming up against anything solid moving back and forth. The vessel, the whole idea of the plan is to lift the vessel level and keep her level throughout the lift. So we will not be loading the plates from the side like we were in the stern.
When we went out the second time with that second plate, in fact it did not part. The steel part of it, the steel plate parted, but the wires still held.
Q: Are you using the same type of steel on both the strap and the plates?
Marsh: Yes. When I said the steel plate in that case actually parted, it stayed in position, though. So even though it wasn't helping in maintaining the load of the vessel, it was providing chafing gear for the wires. The wires were capable of holding the vessel up.
Q: An environmental question. At one point you said there was 45,000 gallons of diesel fuel. Yesterday the Admiral said it. Why did you change that figure?
Marsh: I'm not really totally involved with the environmental side. I'll pass that question on if I can to the CINCPAC Fleet people. They have been tracking with the regulators on any oil releases that have happened. I sort of had my head glued to the actual lifting process itself.
Q: Have you taken samples of the sediment and performed assessments on them? And if you have, what were the conclusions?
Marsh: We actually took samples back long before we came out to see, we had those analyzed at a couple of different universities. What they told us at that time really was that what we thought would be very effective was the coil tube drilling arrangement. That proved not to be quite... In fact it didn't work like we had planned. But what we did was take those samples and compare them to shore-based testing that we did. And the shore-based testing we did with the coil tube drilling actually was much tougher, much more solid soil. So that's why we felt confident that the coil tube drilling would work.
Q: Can you describe, you're talking about lifting the bow with the strap in front. I guess I'm a little...
Marsh: It's a lifting sling, I would call it that because it is not strapped around, it is strapped through the hawse pipe, but there's no plates or anything that is continuous around the bow.
Q: I guess my question is if you have that sling in place it will be teetering (inaudible) what you were talking about when you lift up the stern.
Marsh: Not quite. The answer to that is as you pick... Probably this one. As you begin the pick or the raising of the bow, what you will see is you are initially, she's down in the mud and you start raising the bow you will simply be lifting the bow area weight. She's supported back here where she will actually lever. So we are taking advantage of the weight of the ship itself.
We're going to take advantage of this weight right here on almost, most all commercial ships and a lot of warships are the same. You actually look at it from the midships area which is Frame 45 on this vessel. Aft you normally have 60, maybe 65 percent of the weight of the entire vessel. It comes about simply because most of the major machinery is back there, so you have very beefy, a good term I guess from that standpoint, support system back there. So therefore the weight distribution of this ship is skewed to the stern.
So as we start lifting on the bow we will take advantage of this to help coming up. So we won't be pulling nearly as much as it may seem. It's basically a teeter-totter from that standpoint.
Q: Is the hawse pipe strong enough as opposed to lift the stern? (inaudible) anchor was.
Marsh: The anchor hawse pipe? Yes.
Marsh: Yes. And as I mentioned, our Japanese experts on board confirm that with it. They helped us design the size of those backing plates that will be coming up. So you are not, the picture may be, or the thought pattern may be that you're actually lifting with this shackle pulling up through that hawse pipe, but the shackle will come up against a large plate. That large plate will distribute the load over, in fact, three frames worth of the ship. Frames on the ship are essentially like your ribs, really, from that standpoint. They're major structural members.
Q: How big is...
Q: I think that was about it.
Marsh: I've got to get back out...
Q: ...the plates?
Marsh: I think right now the design is 1.3 square meters.