Sealing up fountain in pond?

[kdlklm]

I've inherited a project that has a fountain in the center of a pond. I'm looking for opinions on the best way to seal up the pond liner around the fountain. The fountain sits about 3 inches into the water when it will be filled. The soil is very sandy so it needs to be sealed well. I'm open for suggestions. Thank you.

[kdlklm]

Photos Attached

[tadpole]

What I would do is to remove the existing concrete pedestal base and pour a new concrete base flush with the bottom of the Pond. Lay the liner as one piece. Place a double layer of underlayment (geotextile) between liner and new concrete base and also between fountain pedestal base and the liner. If client wants fountain to remain at present height, pour a second concrete section of concrete base on top of the liner. Sort a like making a liner sandwich with 2 concrete slabs as the bun. No cutting liner, no sealing, no leaks.