Lagoon Silty Sand

[Arizona3106]

I have a lagoon with silty sand side slopes. I have not visited the site yet, but pictures are attached. This is their 2nd slope failure, and they are seeking outside opinions. I am currently thinking about recommending a geocell product with gravel infill. My second thought is plating the slope face with soil-cement, but the site is about 4.5 hrs away from the lab. So a solution with a lot of lab testing does not feel very desirable. However, the point of this post is to get Eng-Tips opinions, Thank you!

 

[dgillette]

Help me understand the pictures. Am I seeing a slump of a silty sand fill slope beneath a liner? How steep are the slopes? Under what conditions did the slumps occur? Is there a water table, or does the membrane do its thing properly?

I may not know the answer, but I know the questions.

 

[mudman54]

i like the geocells. many a time i've walked down a sandy bluff and the only thing holding the path together is the honeycomb cells.