Question about earthen diked storage area

[chicopee]

Roughly two years ago an existing earthen berm was increase in height to contain 1,100,000 gallons. The material that I noted may have contained clay however this material was full of rocks and appeared greyish and compact when dry.
This spring I was asked to check out the volume within this containment eventho I am not a surveyor or civil engineer(but did have a year of surveying in college from the reknown O.I. Jackson from Montana State College). I used a level, rod and tape to determine the elevations on the top and bottom of the berm and the distances between level and rod positions and between corners on top and bottom of the berm.(note that I calibrate the level before taking the data and periodically checked out the levelness of the equipemnt)
I plotted my results in AutoCAD and created a solid which revealed that the volume was under the 1.1M gallons by 54,000 gallons and that we would need an increase in height of at least 4".
One of the problem during the survey was that the containment floor was partly wet( about 1/3 rd and perhaps 6" deepin some spots) and muddy from all the snow and rain.
So here are my questions:
1)What amount of settlement of the berm could I expect from the time of the augmentation project.
2) Knowing that volume calculations was cheated from the wett condition (perhaps 6"+ deep in the deepest area, is it really worth the trouble to determine this additional volume and how could this be done without getting stuck in the mud and wet to the knee caps.
3) Erosion is evident along the wall where the stairway is located and no grass is growing; also is a visible path along the top of the dike from foot traffic over this two year period. Note a wire fabric was installed to stabilize the soil during the augmentation project. So is it possible that I lost some height from this erosion?

 

[civilperson]

What is the height of the added berm and what was the soil beneath the added beam? Compare the design top of berm elevations with your measured elevations, compare the design finish bottom elevations with your measured elevations. What is the design slope of the berm and what is the design dimensions compared to the measured slope and dimensions? Write the answers to all these questions along with your quantity calculations and submit as a report. You can NOT say why or how the current existing conditions came about but you can give a reliable measurement from your effort.

 

[chicopee]

Unfortunately I do not have the answers to your questions because I was not involved in the augmentation project. Another thought that occured to me is also the possibility of moisture loss concurrent to the other factors that I mentioned above.