Exactly what the title says, an option to fill in a steam geyser, so it is removed. Maybe after research? Or just a deconstruct option? If there is another way to do this, please tell me.
There is already a mod for this. It's a part of a bigger collection but the collection itself is modular which means you can choose to only use the laser drill. The mod is called Enhanced Defense: Phoenix Edition - Modular.
You can get it here:
https://ludeon.com/forums/index.php?topic=6636.0
The section you are looking for is called "LaserDrill". Here's what it does:
QuoteAdds a Laser Drill that allows the creation of new steam vents, and a Laser laserFill that allows you to remove unwanted steam vents. Both of these operations will take a considerable amount of time.