# Site Survey - Stockpile Measurement

What’s your best way to measure stock piles for this? A lot of convergence, and large piles. Any ideas? Best fit would work on the smaller ones, but the larger ones look tough to get a proper floor. Suggestions welcome.

I have found that the greatest variation in volumetric measurement of stockpiles occurs in selection of
1.appropriate base / floor / or elevation plane
2. outside perimeter.

For base plane or floor measurements other programs give you more options, but if using DroneDeploy, then I recommend BEST FIT unless is it completely flat/horizantal/planar surface.

For selection of outside perimeter, draw your vector area according to actual ground around all connected stockpiles which overlap, trying to keep perimeter lying on actual ground surfaces the entire time. If you can, isolate each stockpile to measure individually however if they are connected and overlapping, then your perimeter may have zigzags and odd shapes.

I have done a comparison of a stock pile which I surveyed using our drone, measuring only 22,000 points, compared to a hired LiDAR survey which measured a million points. The hired survey MEASURED BASE PLANE AS A FIXED ELEVATION when the ground is uneven and far from flat. When I matched their elevation plane measuring volume from fixed height I got the exact same volume.

When would you recommend “lowest point” - I though “best fit” was for flat surface on a stand alone pile? Am I wrong? For instance when measuring a pile which stands alone and does not have any covergence or walls = Best Fit, vector points will slice a flat plane across the bottom and calculate volume. If “lowest point” and walls coverge, like two big piles back to back, the vector points would cut out a 3 dimentional plane. For instance kind of like an “L” if vector point were on top of pile and on lower flat floor of pile it would “cut through” pile to connect the dots?

Lowest point would be for the flat planar base, and I believe that it will even be perfectly horizantal but I’m not sure about that, whereas Best Fit as will best fit an uneven surface, and I believe behind the scenes a digital surface is interpolated and used as base… best fit is your 3D cut through a pile.