Shovel Cave Location
This cave is located somewhat centrally on the island but on the north-west side of the mountain. Outside of the cave, three operatives can be found impaled, with the middle one having a slingshot on his belt. The rope gun is required to explore beyond the entrance of the cave, and the rebreather is required to reach the shovel.
It is possible to get past the rope gun requirement at the entrance of the cave by jumping onto the small ledge on the right side of the gap (facing away from the entrance), and then jumping and building an upright stick in the main cave area.
This cave contains Puffies, Fingers, Legsy, and Mutant Babies.
After surfacing from the first dive search by the right wall and you will find the Wetsuit. The pistol flashlight can be found near dead operatives in a large room that contains several twins and fingers.
While reaching the second dive search, there is another path to the left reach to a dead operative with tons of money and some grenades, which can be proven useful later on
The shovel can be spotted laid across the lap of a dead maintenance worker at the very end of this cave. A large, inaccessible area is here that shows the side of the Holosprings resort and luxury bunkers.
Taking the pathway back towards the entrance, a wall will break apart, revealing a Sluggy that can be blown up to access an alternate exit. It is difficult to miss as it's noted by a large crashing sound and many physical rocks will be thrown into the player's path.