敌人：穴居大鼠（Cave Rat）、较小的鼹鼠（Lesser Mole Rat）、豚鼠（Pig Rat）、辐射蝎（Radscorpion）
可搜刮物品：闪光弹（Flare）、治疗针、急救包、狩猎步枪、.223FMJ（两份）、绳子、皮夹克、10mm AP、定时炸弹、手雷、10mm冲锋枪、10mm JHP、撬棍、急救技能书、.44子弹。
- If pressed about Necropolis she will reveal its location. Alternatively, Miss Stapleton sells a holodisk with the location of Necropolis.
- (optional) She can send water to Vault 13 for varying prices. This will add another 100 days to the time limit, but reduced by the same amount for the mutant invasions (500 days normally in v1.0, 13 years in later versions).
Travel to Necropolis.
Use the manhole to enter the sewers and proceed north through the sewers to the Watershed area. If the Vault Dweller takes this route, they will come across a group of friendly ghoul refugees and they can get information on the super mutants from their leader. After this, keep heading north through the sewers and climb up the ladder at the end. Find a building to the north with some super mutants and an imprisoned ghoul. In order to navigate the area without combat, either convince the super mutant leader Harry with a high Speech skill, sneak past, or confuse him by having extremely low Intelligence. Violence is an option as well. Failing to achieve a peaceful solution, Harry will either attack, or send the player character to the Mariposa Military Base.
After dealing with the super mutants, free the ghoul prisoner. If he lives, he will identify the entrance to Vault 12 in the adjacent cell. However, the entrance can be opened without speaking to him.
Ghouls inhabit the Vault area and are hostile during night time. Travel to the third level using the elevator, and enter the command center area. Remove the water chip from the computer. It should be noted that doing this will turn the ghouls in the Vault hostile.
- 500 XP for finding the destroyed command center.
- 7000 XP for giving the water chip to Overseer Jacoren.
- After completing this quest, Overseer Jacoren will give the quests "Destroy the source of the Mutants" and "Destroy the Mutant leader".
- After getting the water chip to Vault 13, all Necropolis ghouls will be attacked in 30 days by invading super mutants unless the Master is killed in time.
- This quest is not crucial to finishing the game. Killing the Master and destroying the vats before the time limit runs out ends the game.
- This quest can be the first the Vault Dweller completes, leaving nigh-infinite time to finish the other quests within 500 days (in v1.0).
- In patched versions of Fallout, more time is added before the super mutants attack, up to a maximum of 13 in-game years.
- If this quest is not completed before the time limit runs out, the game is over, and kicks back to the main menu.
- Find the Water Chip is the first main storyline quest and it is received just after the intro with Overseer Jacoren in front of the Vault 13 door.
- To keep the water chip, simply press the 0 key when Jacoren asks for it. Afterwards, the Vault Dweller will be at the computer, gain the 7500 XP, remove the time limit, get the new quests from him and keep the chip. If the player character has a bag or backpack below the water chip in the their inventory list, this will also keep the chip from disappearing.表达式错误：未预料的<操作符
- There are two ways to "reset" the quest. The easiest is to talk to the water merchants. The other requires that the Vault Dweller kept the chip; returning to Necropolis and using it on the water computer, thereby also undoing the chip quest, which means the Vault Dweller can give the water chip to the Overseer again for 7500 more XP. Using this cheat allows the Vault Dweller to keep the chip and then travel back and forth between the Hub and Vault 13, gaining 8500 XP each round trip and increasing the time limit all the while.表达式错误：未预料的<操作符Template:Navbox quests FO1