Landfill failure

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Dleg

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Well, this isn't technically an "exam" topic, but since this is the enviro dungeon, I thought I;d post these here.

This is what happens when all the leachate pumps fail, are not replaced or repaired for two months, during which time 20+ inches of rain falls onto your landfill: Overtopping of liner system, followed by rapid groundwater contamination.

See that bare section of soil at the bottom right of the pooled leachate? That's where the overtopping occurred, scouring out the "operations layer" (2 feet of gravel) and exposing the liner:

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mmmmm..... yummy leachate. And a whole lake of it!

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^^Those were discharge hoses/pipes from earlier pumps. They're no longer in use. Up to about a year ago, the water inside this particular cell was still clean rainwater, so it could just be pumped out with a trash pump or the temporary pump you can see out in the middle of "the pond". About a year ago, though, the waste pile began to encroach into the cell, and then when the pumps failed in the active cell, the "lake" in the picture became leachate which had spilled over from the first cell. To help visualize this failure, I've attached a rough schematic of the situation.

 
Well, sample results from "the pond" came back positive for leachate (18 mg/l ammonia), so this has now become my official next "big task". Uggghhhhhhh..... I hate enforcement......

:whipping:

 
^^^ Did you receive any other results beside NH3 ?? Just curious because while NH3 is bad there are other consistuent sources that will fowl water quality criteria.

JR

 
^^Not much else - we were just trying to determine if it was indeed leachate. The landfill operator was denying it and saying it was only rainwater, which makes no sense if you understand the design and factor in 2+ months of no pumping. So we went with what we could do locally, which is basic chemistry (DO, pH, TSS), Ammonia, Nitrate, Phosphate, and BOD. Ammonia was the kicker, though - there's no likely other explanation for an ammonia concentration of 18 mg/l. Just as a reference, the ammonia concentration in the actual leachate holding pond was 55 mg/l, so the number measured was consistent with that plus dilution from rainwater collected in the empty cell.

More serious testing will follow, of course. It will be interesting to see what turns up in the monitoring wells. There are two wells within about 300 feet of that spot, and the discahrge point is down in excavated, highly permeable limestone.

 
^^It's the tropics. Mostly just grass and weeds, but there is some woddy vegetation coming in. Obviously, there is a lot at this landfill that is not being properly maintained...

 
Just for completeness's sake, the landfill owner was issued an administrative order and is now in their second and last week to provide a repair schedule and proof that the pumps and related parts have been ordered. As mitigation, they built a clay berm on top of the liner just behind the gravel-topped berm in the picture, but it didn't work. They excavated down to the composite liner, but part of the liner is a drainage geotextile lying on top of the HPDE, and they just emplaced the clay on top of that. As expected, leachate is just flowing under the new berm, through the drainage material. Hopefully the pumps will be reparied soon and that won't be a problem anymore. But I suspect we will be getting hits on the monitoring well...

Bonus Solid Waste question (basic RCRA-D, possibly applicable to exam): If a statisitically significant increase in an Appendix I constituent is detected in groundwater, the landfill operator must move from detection monitoring to a _________ monitoring program, and test for ______________ constituents.

 
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"Assessment" monitoring and "Appendix II" constituents....

Here's a nice, recent shot of the conditions at the landfill, almost 2 years later:

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"Assessment" monitoring and "Appendix II" constituents....
Here's a nice, recent shot of the conditions at the landfill, almost 2 years later:
Holy Necropost, Batman!

I don't get it...the pond is still there, but they just tried to "pretty it up" by adding some livestock? Does this mean that the problem has been fixed, or not after 2 years?

 
The problem is pretty much still not fixed. The livestock either broke in or were let in only recently. I'm headed up there in a little while to go see if they have been removed yet.

I just thought those were hilarious pictures. Sad, but hilarious.

 
Pretty cool actually ... it always surprises me at how different people view disposing/managing waste residuals.

JR

 

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