This quick tutorial will show you how to (kind of) get rid of terrain anchors.
Step 1: Terrain anchors
Ok, first you nee
d to find your terrain anchors.

Step 2: H O L E

Step 3: Throw your terrain anchors away.
Thirdly, throw your terrain anchors into the hole. Note: You may have to push your terrain anchors down the hole by picking them up and dropping them because they may get caught on stuff on the way down.

Step 4: G O N E

Step 5: enjoy life

Thanks to Bonez for his great guide, all credit to his effort. you can also read the original guide from Steam Community. enjoy the game.