Civil engineering/Earthworks: Twice as many tons as offered*

Hello everyone,

I'm not sure if this is the right forum.

According to the soil report, we had to excavate 0.80 cm and fill with frost protection gravel.

Now we have received the invoice and are very surprised because the tonnage is much higher.

163 tons were quoted.

Material: mountain gravel (0-45 I estimate) 16.10m x 12.00m

In the billing, it is now 375 tons. And that even though the site manager said it was a great soil.

That can't be right, can it?

Please respond as soon as possible.

Thanks! Best regards Talulah