Volume measurement - snow covered piles

[hudikflygfoto]

I have been hired to do volume measurent of stockpiles using my drone. The measurement is going to be performed once every month during a year of the same location. The problem is during winter when the piles are  covered with snow.
Is there a way to  calculate the volume without taking the snow into account?
If I measure the snow depth, is there a way to lower the height of the pile with the same number or do you have a better way to do this?

[mbrett]

I do more or less the same thing where I work. I wouldn't try shifting the flight but instead calculate the surface area of the piles and estimate the depth of snow to come up with a volume of snow. The piles I calculate tend to accumulate less snow than the surrounding area so be careful estimating how deep the snow is on the pile.

Hope that helps

[hudikflygfoto]

Thanks! I will give that a try.   
Peter