Underwater removing makes old land reappear

Summary:

Steps to reproduce:

  1. Mine underwater ground away
  2. Build a layer of slabs on the 2nd lvl of removed from above
  3. Destroy the slabs when its build

Expected Results:
Slabs are removed and no land appears, just water

Actual Results:
New land to mine appears

Notes:
Only tested on 1 layer due to placing of handmade ship.

Attachments:

Version Number and Mods in use:
Alpha 18

System Information:
Win 10 64bit
i5-4210H 2.9GHZ
8GB RAM

A post was merged into an existing topic: Removing slab results in sculpted terrain