Oil tank leak 912ULS

I just purchased this airplane and flew it about 17 hours to my home airport. During that time I noticed a small amount of oil along the belly of the plane developing. Upon doing some investigating I found this on the bottom of the oil tank. Is that a bolt that screw into the tank or is it welded or molded into the tank? Will this require a new tank replacement? This is on a 912ULS.

If it were me, I would carefully clean the area around the bottom of the oil tank and see if I could better pinpoint the leak's source (a little talcum powder helps to ID the source).  Potentially the leak could be from the copper o-ring between the boss and the quick-drain fitting or the small o-ring inside the quick-drain itself -- you can replace this O-ring with a new one. The boss (nut-like thing at the bottom of the tank) is welded to the bottom of the tank.  You may find that someone previously tightened/removed the quick-drain fitting incorrectly and over-stressed the boss creating a leak.  The correct way to tighten/remove the quick-drain or the OEM plug is to "double-wrench" the assembly so as to not stress the boss/tank bottom interface.