Thicket Excavations

Thicket Excavations is a quarry located in the northwest of the Commonwealth in Fallout 4.

Background
Originally a granite quarry, this quarry has obtained a reputation across the Commonwealth for producing the finest mirelurk meat due to the waters giving it a better flavor.

Layout
The pre-War sign displaying the location's name is directly outside of the fence. It instructs visitors to check-in at the office, wearing safety equipment at all times, and includes a reminder that the area is not open to the public.

A fenced-in quarry area that has been flooded, it is found to have scattered pieces of cut stone around it. There are stairways leading up the north side of the quarry and a sloped ramp that extends into the water. The top-level on the east side includes an elevator as well as a camper in which Sully Mathis's terminal can be found which details his plans for restoring the quarry for use as a base. There are several campers spread out around the nearby area.

If the water is drained from the quarry during Pull the Plug, 24 hours have passed and one has reached level 12, then Sully will then (when the Sole Survivor next returns) be found to have brought in his gang of raiders, and these hostile raiders will be found spread out throughout the quarry. Sully Mathis will now be found to be much more powerful - minimum level 30 - and like the raiders will henceforth be implacably hostile regardless of any prior help he was given. Three mirelurk pens will also be found in the area.

There is a chemistry station part-way down towards the bottom of the excavation area. It is in a little shed on the south side of the quarry. At approximately the midsection of the quarry on the north side, a weapons workbench is accessible.

Loot

 * Taboo Tattoos issue #2 - In a metal trailer caravan (the one closest to the excavation area) on the south side of the excavation area and directly southwest of the water pump.
 * Sully's journal - Holotape in the east trailer inside of a terminal.

Related quests

 * Pull the Plug: The Sole Survivor meets a man named Sully Mathis who needs help unplugging some pipes to drain the quarry.
 * Raider Troubles: A group of settlers is struggling to defend themselves against a nearby group of raiders and asks the Sole Survivor for help.
 * Randolph Safehouse: The Railroad agent Mister Tims will leave dead drops in the form of six holotapes for the Sole Survivor, containing information about possible hazards to the Railroad's escort and escape of synths out of the Commonwealth. They can assist in these efforts by clearing out the location of hostiles.
 * Quartermastery: Scribe Haylen has identified the location of a piece of technology she wishes to retrieve and catalog. She asks the Sole Survivor for help in bringing back the technology in one piece.
 * Cleansing the Commonwealth: Knight Rhys gives the Sole Survivor an assignment to clear the location of what he calls "abominations" to further the aims of the Brotherhood of Steel.
 * To the Mattresses: The synth-hating L&L Gang is a major threat to the Railroad. Desdemona has a lead on them and asks the Sole Survivor to help neutralize their members.
 * Stop the Raiding: The Sole Survivor becomes aware of a group of settlers being terrorized by nearby raiders and can offer to help.
 * A Permanent Solution: One of the leaders of the Nuka-World raider gangs tasks the player character with neutralizing a target to further their gang's aims.

Appearances
Thicket Excavations appears only in Fallout 4.

Bugs

 * Upon arrival at Thicket Excavations, there seems to be a foglike low-res concrete-floor, hovering above most of the real surfaces, and it persists underwater. It is the high distance version of the model one should only see when the object is very far away. This manifests in that both the Sole Survivor and Sully Mathis wade knee-deep in concrete, Sully always hovers around the compressor/pump, before the Sole Survivor suddenly falls into the water or the access-way leading down into the excavation. The impact of this bug can be negated by restarting the game.
 * If one swims underwater to enter the excavation site before draining it, they will fall down to the floor and be able to walk and shoot their gun underwater. In some cases, Dogmeat may also teleport down to the player character and swim in place as he tries to follow them.
 * Occasionally, the caged mirelurks will spawn outside of their cages. Caged mirelurks only turn hostile when attacked, or when the Sole Survivor (or a companion) enters their cage, so the mirelurks will roam around without turning hostile.
 * Similar to one of the USS Constitution bugs, companions tend to repeat their location-specific comments over and over as long as they are in the quarry's vicinity.