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Monday, May 28, 2012

Debris Part 13

Part 1
Part 2
Part 3
Part 4
Part 5
Part 6
Part 7
Part 8
Part 9
Part 10
Part 11
Part 12
Part 14

Let's move over to the London Avenue canal to take a look at its December, 2010 - June, 2011 remediation project, which was being constructed at the same time as those at 17th Street and Orleans Avenue. I've written about it before, on March 3, 2011.

London Avenue canal remediation - the basics

The London Ave project was far more complicated than the 17th Street project. It consisted of a great deal of sheet pile placement to cut off seepage along the canal, along with buttress (concrete embankment) construction and even tying into existing sheet piling left over from decades earlier. The objective was to raise the Safe Water Elevation along the entire canal to 8 feet, based on calculations of a wide variety of failure modes.

The work was initially concentrated on 11 of the 43 sections, or "reaches," into which the Corps and their consultants and Black & Veatch subdivided the canal. Soon after the project was awarded, however, four additional reaches were added. Difficulties in construction and a failure of resolve also led to the deletion of a reach. Here's the entire universe of project reaches:

and here's a summary of changes made during project construction:

The main problem with the canal was seepage. The I-walls that existed on August 29, 2005 were driven into sand, and they were way too short to cut off water from seeping beneath their bottom tips. So additional, much longer sheet piling was to be driven behind them to act as a seepage cutoff. In selected areas where piling couldn't be placed, grout would be injected in the soil and mixed, just as it was along many, many reaches of the 17th Street canal remediation project happening at the same time. Many of the reaches had sub-8-foot Safe Water Elevations due to seepage concerns, as seen here:

The numbers in blue come from the October, 2010 London Avenue Canal Safe Water Elevation report (Revision 5). Three of those in green are from a January, 2011 memo sent to the Corps by Black & Veatch after the contractor had mobilized. That memo showed that reaches 7, 8, and 28 were likely also vulnerable to seepage if one considered the canal bottom as "open," or just a layer of sand with nothing on top of it. (I wrote about "open bottom" reaches in detail in this June 30, 2011 post about the 17th Street project.)

I believe that January, 2011 memo is what got those three reaches added to the project. I don't know why reach 36 got added at the same time as 7, 8, and 28, but considering what was done on 36 (placing sheet piling to cut off seepage) was the same as on the other three reaches, it is likely there was some recalculation for Reach 36 showing it was also seepage-vulnerable.

A secondary problem existed in the height of the walls above the top surface of the levees. This was referred to as "stickup" and it was limited to 4 feet after the post-Katrina surge levee failures. There's much more about stickup and the Corps' kinda-sorta solution at the end of this post. All you need to know now is that the Corps addressed it by placing concrete embankment on top of the existing levees to make them taller.

To actually construct this stuff, the Corps needed to scalp off the top few feet of the levee in any given reach. A flat area was needed to mount the pile driving equipment during construction. So dirt was being taken out of the existing London Avenue canal levees en masse during the entire remediation project. And, as with 17th Street, it turned out those existing London Avenue levees were filled with junk.

In this post we'll be relying mostly on the contractor (Integrated Pro Services, or "IPS") Quality Control, or "QC," reports. I also got the Corps' Quality Assurance ("QA") reports. Here's links to all the files:

Contractor QC reports, Dec. 23, 2010 - March 31, 2011
Contractor QC reports, April 1, 2011 - June 30, 2011
Contractor QC reports, July 1, 2011 - August 25, 2011
Corps QA reports, January 8, 2011 - March 31, 2011
Corps QA reports, March 31, 2011 - June 30, 2011
Corps QA reports, June 30, 2011 - August 28, 2011

Rock and sand

Let's check in with the contractor on February 25, 2011:
"Reach 10 and 11 - Structural Excavation
[...]
The material that is being excavated at this reach is a combination of rock and dirt. Due to the rock and dirt mixture, this may propose [sic] an issued [sic] when backfilling begins and getting a compaction test to pass."

This was not the only site along the canal where excavation was taking place. Chunks of existing levee were being removed off of at least seven other reaches of varying lengths in late February and early March. And on March 3, 2011, the seemingly inevitable was reported in the QC report:
"Met with Frank (USACE Geotech), about the structural excavated material from reaches 30/31/32/33/34 and Reaches 10 and 11. The soil proctors from the material excavated is not approved to put [be] placed in the levee. USACE will provide an answer on this as [sic] a later date."

So once again, existing soil along many spots on the levee was found to be unsuitable to be in a levee. We knew from the February 25th report there were rocks in the Reach 10 and 11 material, but the Reach 30/31/32/33/34 material was unknown as troublesome until this report. Details came the next day. From the March 4, 2011 QC report:
"Per [USACE administrative contract officer] Greg Schultz, the material that was excavated from Reaches 30/31/32/33/34, to be used as structural backfill [i.e. put back in the levee], will need to be blended with hauled in material to get the sand percentage down, to allow excavated material to get a passing soil proctor for approved levee embankment. An additional soil proctor will need to be taken on material after blending has occurred.

Also, Reach 10 and 11 material will need to be ran through a shaker to allow stone and rip rap to be sieved out and then need[s] to be blended with hauled in material to get a passing soil proctor for approved levee embankment. Greg stated we can do sand cone test on this material that will be used for structural backfill in these reaches."

Never let it be said the Corps couldn't squeeze the hell out of a penny, even when there was no good reason to do so. Instead of simply replacing the bad soil (how cruddy must the soil have been on 17th Street that it wasn't eligible for sifting or blending, but was instead disposed of?), they said to re-use it after sifting or blending it. It's nice they're looking out for the people's dollars, but that seems poundfoolish in the extreme.

And let's not forget the fundamental fact that if there was debris in the top of the levee, there was likely debris in the bottom of the levee. But, just as on the 17th Street remediation project, there was no further investigation of the levee integrity. The project just kept motoring onward.

"Leaking through," "leaking through," "rushing through," "water is getting into street"

The debris issue wasn't the only landmine that week. Construction had exposed a nasty secret: the canal was leaking badly. The February 28, 2011 QC report sets the stage:
"Reach 35A - Water from the canal is leaking through the existing I-Wall at Station 102+33.56. Appears the existing water stop has failed and when canal level raises, water is leaking through this gap. QAR [Corps Quality Assurance Representative] was informed about this issue."

The water rose in the canal again later in the week. The March 4, 2011 QC report contains the following alarming passage:
"Reach 10 and 11: Canal water is leaking through existing I-Wall between stations 74+00 and 75+00. Appears the water is coming through the flood side levee and entering protected side through existing sheet piles. The canal water is at +/-1.28'. QAR was informed about this issue."

That is a truly terrifying paragraph to read for any New Orleanian. Six years after Katrina, the London Avenue canal was leaking like a sieve when the water just inches above normal tidal levels (usually about 0-1 foot).

The Corps was also freaked out, as the next paragraph reveals:
"Met with [USACE contracting officer] Greg [Schulz] and [Corps project engineer] Chuck [Brannon], the[y] stated they would get to the areas with greater risk from seepage as the canal water rises. The reaches with these risks/concerns are: Reach 13, 20, 10, 32. [Prime contractor] IPS expressed that the way the work was planned [the] majority of the reaches were planned to [be] started toward the end of the project and the coating of the sheet piles have not started for these reaches. IPS will follow up with LB Foster to see if the coating of the sheet piles can be moved up to allow for sheet piling installation to occur earlier. Also, will follow up with [sheet pile installation subcontractor] Blue Iron to see if another Giken Piler can be mob[ilized] onto site to begin sheet piling installation in these reaches. IPS express[ed] that this would be [a] cost impact to mob[ilize] additional equipment onto site to get these reaches completed."

Let me simplify that: the Corps wanted to reshuffle the entire construction schedule, already compressed to the first six months of 2011, to have sheet pile installed at really, really risky locations that were already leaking when the canal was at very mildly elevated levels. It's good they wanted to address this kind of thing as quickly as possible, but one has to shake one's head at what it took for them to feel some sense of urgency after six years of dithering - actual canal wall failures in front of their eyes. Were the 2005 failures not enough?

By the way, that listing of the riskiest reaches contains a typo. Reach 20 wasn't part of the scope of the project, but Reach 30 was. According to the October, 2010 London Avenue canal Safe Water Elevation (SWE) study, here's the seepage SWE's for those reaches:

Reach 10: 3.1 feet
Reach 13: 1.5 feet
Reach 30: 2.5 feet
Reach 32: 2.9 feet

Reach 20 had a seepage SWE of 10 feet, further confirming the typo.

Reach 35A started leaking again the following day. The March 5, 2011 QC report notes scarily:
"Reach 35A - Water is rushing through where I-Wall and T-Wall butt up against each other at Station 102+33.56. This is caused by the heavy rains and south winds and London Canal water levels are up causing water to leak through this gap. IPS was directed by Contractoring [sic] Officer to build a temporary berm around the area to equalize the water level and equalize the water level and prevent flows from the canal.

The canal stage at Filmore [Avenue] bridge is 2.24' at 0800"

This is Keystone Kops territory. 2.24' is a pittance. IPS must have been so pleased they signed on for the clusterblank that is the London Avenue canal (Note: the Reach 35A waterstop was replaced a couple of months later).

The leaks didn't stop with those in early March however. At Reach 36 (east bank just south of Robert E Lee Blvd), the QA report for May 20, 2011 tells us,
"Eugene Kennedy
Note leak at north end of Reach 36. Waiting to see if water from the canal will rise and flow to the street"

He didn't have to wait long. The QA report from the next day, May 21, 2011, says,
"Eugene Kennedy
Note two leaks at north end of Reach 36. Leaking at wall joint at end of I-wall and a boil about 20' south. Water is getting into street. High tide just over 2' in the canal. Instructed contractor to build earth berns to contain the water."

Once again, water levels of just 2 feet in the canal started it leaking. All these incidents (and there is a shocking number of them in just three months - imagine what had been going on for the previous six years that no one has taken note of!) point up just how fragile the entire London Avenue canal is, and why it should have been completely replaced with an Option 2-style, concrete-lined, surface level channel.

And don't forget - the public was never alerted to any of these 2011 failures.

Corps knowingly tells contractor to reuse unsuitable levee material, and contractor does it

Anyhow back to debris concerns. Remember that Corps contracting officer Greg Shultz said to blend and sift the sandy and rocky soil pulled from reaches 10, 11 and 30 through 34 with good soil and put it back in the levee on March 4, 2011? While it's unclear if the blending took place immediately after the 4th, it seems that wiser heads tried to prevail. On March 22, 2011 the QC report read:
"Received a verbal from Greg Schultz (CO) to bring in imported material fill, instead of blending the existing material with imported material. (RFI 0025 and 0025). Also, stated that the excavated material from the Reaches will be hauled off to the 17th Street project at staging easement. IPS will continu[e] to place the imported material already received on site (for blending purposes) for backfill/embankment for Reach 30 but once the imported material is used up, IPS will not proceed until an RFP is received by the USACE. This will be an impact in schedule and cost increase."

That potential cost increase would get bigger after more junk was found at Reach 13, perhaps the most dangerous reach of the canal, on March 23, 2011:
"Reach 13 ... The material that was being excavated consisted of rock/brick/dirt material, appears to be the same [as] excavated material at Reaches 10 and 11."

Apparently, though, the Corps just couldn't resist taking shortcuts. Just nine days after seemingly settling on importing clean fill to replace the bad material (and placing some of it) the March 31st report reports another reversal:
"Met with Greg (ACO) and Chuck (PM) on site concerning the excavated material from the Reaches. Greg verbally stated that the USACE wants to use the excavated material from the Reaches. USACE is fully aware that the excavated material did not meet the soil classification for levee material. Greg also stated to remove all rip rap and large boulders from excavated material prior to placement of structural backfill."

Unbelievable. And even more unbelievably the recycling of the crap soil within the London Avenue project got beyond the talking stage because the April 3, 2011 QC report says:
"Reach 11 - Structural Excavation
[...]
The material that is being excavated at this Reach is a combination of rock and dirt. All material was loaded into dump trucks and hauled to Reach 31 for structural backfill."

This apparently was so remarkable that Corps QA rep Gene Kennedy even noted it on his April 4th report:
"Spoils from 11 placed at 31 - cobbles 12"-16""

Rocks over a foot in diameter placed in the levee at Reach 31. Great.

So let me get this straight - they dig stuff out of the levees that is so unusable that a later report mentions that "large boulders" have to be removed from it. Then they decide, "sift out the big stuff, and blend the sandy stuff." Then they say, "no, no, bring in clean stuff and send the bad stuff to 17th Street." THEN they say, "No, hold on, go ahead and reuse the bad stuff as it is, even though we know it's very, very bad." At that point the contractor covered his ass by writing the March 31st and April 3rd reports, knowing that someone, someday would come looking. Today is that day.

How much unsuitable soil got put back in the levees?

So did the Corps continue putting unsuitable material back in the levees at London Avenue, or was it shipped over to 17th Street, or was it set aside in a fit of sanity? There's no indication in the 17th Street QC and QA reports that material was being received from the London Avenue site. All the dirt they got came from either the Bonnet Carre Spillway or (after the spillway was opened in the late spring) the Willow Bend pit in Donaldsonville.

One has to do some deducing with what happened at London Avenue. Assuming the QC reports for London Avenue are complete, one notices that they were scrupulous about noting when materials arrived on site. This included delivery of clean levee embankment. Before March 31st, there were repeated mentions of receipt of such and such number of trucks of imported approved fill. There were also mentions of unsuitable levee material being taken "off site."

After March 31st, there were no more mentions of deliveries of approved fill until mid June, and then only for a single day. Also after the 31st, the mentions of sending unsuitable material "off site" also stopped. Instead, whenever excavation was happening, it was always noted the dirt coming out of the levees was sent to the onsite stockpile on the east side of the canal near Mirabeau. In one case (at Reach 13 on the west bank), material was not even sent to the main stockpile, but was instead set right next to the levee. Also after the 31st, levees continued to have dirt piled back on to them after sheetpiling or jet grouting was completed. Where was that dirt coming from?

There is apparently only one answer - the dirt being placed on the levees after the sheetpiling and jet grouting was the same dirt being dug out of the levees. The contractor appears to have followed the Corps' March 31st instructions to a "T." There are no mentions in the reports of blending, sifting, or any treatment of the bad material when levees were built back up. The Corps just dug out bad stuff, and put it right back in. As least that's how it appears.

Because the London Avenue unsuitable material started getting explicitly mentioned again in the QC reports on May 31, 2011, less than a month before substantial completion of construction:
"Loaded and hauled out "unsuitable" levee material off site. Loaded out thirty-seven (37) trucks of "unsuitable" material at eighteen (18) yards per truck with a total of six hundred and sixty-six (666) yards hauled to off site yard."

This went on for another 3 days, until 2736 cubic yards of unsuitable material had been hauled off to points unknown. Did that 2736 cubic yards account for all the bad material that remained on site from mid-March? Probably not. We can only go with the evidence in front of us, and the evidence - including an explicit mention of unsuitable soil going back into a levee on April 3, 2011 - points to repeated, knowing, and dangerous reuse of material unsuitable for levee construction in the rebuilding of the London Avenue canal levees from March 31, 2011 until the substantial completion of the project in late June, 2011.

Reach 35 - never remediated

You'd think that would be the worst of what happened on this project. That is, until you read about Reach 35.

Reach 35 is no ordinary, sand-filled, debris-ridden, underengineered London Avenue canal reach. In 2007, the Corps believed it was the weakest reach along the entire canal. Reach 35 was the site of the ridiculous London Avenue Site Specific Load Test. This was the crazy exercise that involved building a cofferdam around some of the east wall of of the canal and filling it until the wall moved or leaked. The results (Corps: "we can load the canal to 5 feet instead of 4 feet") were found to be based on miscalculations within a month of their announcement. And by the time a comprehensive geotechnical evaluation of the canal was underway in 2009 and 2010, the Load Test was mostly discredited as inapplicable to anything but Reach 35, and even then the conclusions were shaky. Nevertheless, at one time the Corps believed Reach 35 to be the weakest section of the canal.

So it is with great surprise that one finds the following contract modification:
"Contract No: W912P8-10-D-0010 0004
Modification No: 1B
Effective date: 11-Apr-2011
Delete all work associated with Reach 35 (Stations 103+50 - 115+68)
Total contract price is decreased by $246,363.00"

That's over 1200 feet of London Avenue canal levee which, up until April 11, 2011 the Corps felt needed to be remediated in order to get its Safe Water Level up to 8 feet. So what happened? We find the answer in the QC reports.

On the very first day of real construction - January 28, 2011 - this is what the QC report said:
"Began locating sheet piles at Reach 35A & 35
[...]
Reach 35 - no sheet piles were located at Station 104+65
               - excavated to an elevation -2.37"

The plans for Reach 35 involved using an abandoned line of sheet piling on the landside of the existing I-wall as a foundation for a new concrete embankment. That embankment would have its top surface at elevation 4 feet. Remember that the objective of this project was to get safe water elevations of 8 feet along the entire canal, despite the fact the walls were actually much taller than 8 feet above sea level (12 or 13 feet in most cases). The Corps was just ignoring that extra height and simply imagining the walls were only 8 feet tall. Post-Katrina design rules limited the amount of "stickup," or height of exposed wall above a solid surface like a levee top, to 4 feet. So if the walls were only 8 feet tall (remember, this is the Corps' imaginary world, not the real one), then the 4 foot stickup requirement would mean the top of the levee should be at 8 minus 4, or 4 feet. Thus the new concrete embankment at Reach 35, where the stickup requirement was apparently the governing failure criteria, among many types of potential failures. Here's an annotated version of the typical cross section of Reach 35 summarizing all this (from the November, 2010 Issued For Construction set of drawings):

The abandoned landside sheet piling was - according to the drawings - supposed to have its top at an elevation of +2, less than a foot below the existing levee top. The horizontal position relative to the I-wall was unknown, so it wasn't surprising they didn't find it the first time. They tried again the following Monday, January 31, 2011, moving about 1000 feet north:
"Excavated to locate sheet piles in Reach 35 at Station 114+78
a. dug 2' off wall and 6' deep - no sheet piles located
b. dug 6' off wall and 6' deep - no sheet piles located
c. dug 8' off wall and 6' deep - no sheet piles located"

Okay, so that sounds bad. In fact, the onsite Corps representative was ready to give up:
"QA witness[ed] the exploration of the sheet piles at the above station. He agreed that it appears there are no sheet piles located in Reach 35."

Again, just to clarify, they are referring to the abandoned landside sheet piles, not the sheet pilings actually holding up the wall.

There was a project meeting three days later, on February 3, 2011. Reach 35 was discussed:
"[Corps project engineer] Chuck Brannon instructed IPS not to excavate Reach 35 until [they receive] an answer by USACE on the existing sheet piles. He also stated that if the existing sheet pile cannot be located, no work would be performed in this Reach."

Already the Corps was ready to throw in the towel, just a few days after beginning construction. That hardly sounds like an organization that proclaims itself to be "Building Strong."

But Corps project engineer Carmen Williams was not so easily deterred. The February 4, 2011 QC report says,
"Carmen Williams instructed IPS to do another exploration for the sheet piles in Reach 35. She instructed to excavate 4 feet off I-wall and to an elevation [of] -2 at station 109+00"

Ms. Williams apparently had the touch. The February 7, 2011 QC report tells us,
"Reach 35
Per the [Corps Quality Assurance Representative, or] QAR, excavated at Station 108+00 to explore for existing sheet piles. Excavated a trench 2' wide and 8.5' long to an elevation of -2.62'. Located the sheet piles at this location."

Eureka! Unfortunately they were about 4 feet below where they should have been, but at least they found them.

However, the news got worse:
 "The sheet piles appear to be disintegrating and breaking apart. [Corps personnel] Dan Brady and Chuck Brannon on site to view the findings."

That's the last we heard of Reach 35 until the contract modification was issued in April. It was just yanked from the project like it was never even in it. And when the Corps trumpeted the completion of the remediation projects later that summer, they didn't let anyone know that over 1200 feet of London Avenue canal I-wall and levee that had been due to be fixed was in fact not fixed.

This was not an unsolvable problem. There were other reaches within this same project that had also had the Elevation 4.0' concrete embankments installed. They had not relied on placing the embankments on the existing abandoned sheet piling, but had placed it atop new sheet piling driven even further to the landside. Admittedly, in those cases the new sheet piling was required to act as a seepage cutoff, but it did do double duty as a foundation for the new concrete embankment. Here's an example, using the same notation I used above for Reach 35's original design:

Note the existing abandoned sheet piling between the wall at the left and the new piling on the right. The Corps could have easily driven sheet piling the same way along Reach 35 to act as a base for the concrete embankment, even though they believed it wasn't strictly necessary for seepage concerns (Remember - in 2007 they believed Reach 35 was the weakest reach in the canal, and that seepage was a major concern there. But by 2011, it was only the stickup that was a concern. Go figure.).

But they chose not to. And that reach remains unremediated to this day, with a safe water elevation of around 6.2'.

Wrapping up

Here's what we learned about the 2011 London Avenue canal remediation project:

1) The soil in the levees as they existed before construction had rocks and sand in it. Some rocks were boulder sized. There was enough debris to term the soil "unsuitable" for levee construction. There was no follow-up to determine the extent of this debris contamination within the project reaches, or in reaches outside the project.

2) At first, the Corps wanted to reuse this bad soil as structural backfill on the project by blending the sandy stuff with good stuff, and sifting the rocks out of the rocky stuff. But then they apparently decided to use the bad soil as is, and just put it back in the levee, in one case moving it directly from one reach to another in the same day. This was done knowingly, not accidentally, and may have been done on a large scale for much of the term of the project.

3) One reach - Reach 35, a 1200 foot stretch of the east bank of the canal - did not get remediated at all, despite being in the original plans and specifications and also being the first Reach to be excavated. Reach 35 was the site of the 2007 London Avenue canal Site Specific Load Test, and as such, was believed at that time to be the weakest stretch of the entire canal. It was removed from the remediation project half way through despite numerous possible solutions to a problem which arose in the first weeks of construction. At the end of substantial construction, the Corps did not acknowledge this to the public.

4) In a three month span between late February, 2011 and late May, 2011, the canal sprung four different leaks, despite the water elevation never rising past about 2'-3". None were reported to the public.

This is very, very not good.

Next up - Orleans Avenue. And I'll tell you right now they were three for three in finding debris in the outfall canal levees.

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