May 10, 2012 – Cell 4 full

Thursday, May 10

We tried to head out to the dredge site at our usual time but the flat boat motor was acting up and Timmy had to fix it before we could leave. Also, we had never unloaded the Goose of the lumber we had brought, so decided to do that before we exhausted ourselves today. Timmy moved the Goose over to the shell landing, and then brought the 4-wheeler and trailer out of the workshop.

We had to pass by the killdeer nest which was on top of a former burn pile, and when the parent popped up to try to lead us away, we discovered the eggs were hatching! Three chicks were huddled together waiting for their last sibling to emerge into the world. With us passing back and forth, the driest chick took a quick walk-about, and the nervous parent finally settled down to ignore us. The precocious fluff-ball chick was so cute running and stopping on its long legs then bobbing just like an adult! It finally made its way back to the parent and dove under and into the protective feathered shelter.

Figure 11. Killdeer chicks and egg (left); adult with precocious toddler (right).

Figure 11. Killdeer chicks and egg (left); adult with precocious toddler (right).

Even with these distractions, we made it to the dredge just after 8:00, and got the dredge going at 8:30.  The strap that is hooked into on the pump is starting to fray and increase our level of pump-loss anxiety, so we paused briefly to change the hook on the pump. Since I moved the discharge at the end of the day yesterday, we pumped for an hour to make a delta at the current position of the outfall.
At 9:25 we stopped. Timmy moved the port traveling cable back by tying it to another tree, and then we went to the pond to move the outfall. The water level in the pond was at -4” ML, but the substrate level of Cell 4 is roughly +2” ML, with water and mud escaping through the marsh and containment into Cell 2, making a rather large delta below marsh level.

Figure 12. Effluent escaping from Cell 4 to the left had created a delta of fluid mud (no ripples) in Cell 2 to the right. The blow-out under the reed containment is also shown.

Figure 12. Effluent escaping from Cell 4 to the left had created a delta of fluid mud (no ripples) in Cell 2 to the right. The blow-out under the reed containment is also shown.

It took 3 hours to pull a 40 ft flex hose out of Cell 4 and move the outfall to the low spot (+1” ML) in the middle of the cell. We were both covered in mud by the end of it. I don’t know how we could have managed without an airboat.

While Timmy was warming up the airboat, I took the pirogue to the west side of Cell 4 to untie the pontoon from the cane anchor, then hauled the rope over to the marsh landing we use between the north cells and south cells. The delta in Cell 2 was thick and difficult to pole through, so I threw the rope to Timmy who was now on the marsh island with the airboat, and poled around to the landing. With me tugging and pushing and prying, and Timmy banging on the hose connector, we finally got it apart. He taped up the end of the hose still attached to the pontoon so it wouldn’t fill with mud, tied a rope around the end, and then tied that to the airboat.

Then it was a tug-a-war between the airboat and the mud. The curve of the hose was pulling against the mud in the cell, and scooped a good bit of it into a circular hill as the airboat finally made headway. I stood to the side where I could see the hose and Timmy could see me, and let him know when the next connector came into sight. Then he untied the airboat and circled around to get the next connector apart. This one took longer, but we finally succeeded. Back in the airboat, Timmy went back to the taped end of the hose and hauled the freed 40-foot flex hose over to the levee.

Figure 13. Timmy starting to disconnect the hose after pulling the free end across the marsh.

Figure 13. Timmy starting to disconnect the hose after pulling the free end across the marsh.

When he returned, he greased up the fittings, and reconnected them. The ropes connected to the pontoon were then tied to the airboat, and Timmy headed across the cell to pull the outfall to its next position in the lowest part of the cell. Once again, it was apparent that the airboat made very little impression on the mud. I walked around the cell across the containment between cells 4 and 5 to meet Timmy on the other side, where I untied the rope from the airboat and brought the free end back around to the pirogue landing.

Figure 14. The airboat skated across the mud to pull the pontoon into its new position.

Figure 14. The airboat skated across the mud to pull the pontoon into its new position.

Figure 15. The track left by the airboat barely made an impression

Figure 15. The track left by the airboat barely made an impression.

Figure 16. The discharge was pulled close to the marsh for its last delta.

At 12:15 we were back on the dredge and pumping mud again. After an hour, we stopped again to move the outfall.

Fluid mud was covering the cell again. This time it took 2 hours with the airboat to pull 2 sections of hose out – a 20 ft hard hose and 40 ft flex hose, and bring the outfall back to the marsh island between cells 4 and 2. Everything was covered in mud!

Figure 17. With the pontoon on land, Timmy was cleaning off the pervasive mud.

At 2:15, we were pumping mud again for another hour. We stopped at 3:15 with Cell 4 determined to be full at an average of +2” ML, and Cell 2 with a large addition of overflow. We disconnected the hose and Karen crawled out on the pontoon to untie the extraneous broken ropes and straps that cluttered the pontoon. With that loose, we pulled the last hose section and the pontoon onto the marsh platform by hand.

Figure 18. The pontoon and last section being towed to the dock.

The airboat again was used to pull everything to the dock. The pontoon and last section of hose was left tied to the dock, ready for deployment in Cell 1 next week.

With Cell 4 filled, we’ve completed 0.659 acres of fill, roughly a foot deep, to bring the substrate up above marsh level. With just two people working parttime, this took 145 hours of pumping in just under a year. I will be doing a time/cost assessment soon, to see how much of our time was spent on 1) pumping, 2) repairs and maintenance, 3) moving hose, 4) and building containment. That should be an interesting spreadsheet.

Figure 19. This is an estimate of the status of the study cells as of May 11, 2012. Cells 4 & 5 are filled to marsh level or above. The yellow crescents represent the 16 locations of the dredge outfall that filled Cell 4 in 72 hours. The red arrows show where sediment was escaping the target area. Green lines represent completed containment, and the orange lines represent planned containment. White dots represent PVC poles placed by LSU as depth markers. Measurements are in inches.

 

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