Up the Stream

Investigate the river near Sawmill and identify its contamination source for Lab Rat.

Show on map

Earlier source versions · See version & sources

Lab Rat

Required tasks (1)

I went, I saw, I conquered

What to do

Map links are approximate objective references. They do not establish an entrance, floor or item surface.

1
Check the source of the contamination.
131, 142 131, 142 130, 142

Finish & hand in

Stay alive during the task.

Rewards

870 USD

Walkthroughs & video

Detailed wiki reference, unknown patch

Version unknown · Older walkthrough. Check against your current objective.

Follow the river west of Sawmill to its mouth and the large pond. The wiki reports grid 132,142 for the contamination source.
The reference describes an abandoned truck and bodies at the site. Investigate one of the bodies and report to Lab Rat. The grid is not visually confirmed in the current patch.

Open source

Version, sources & details

The guide combines documented older builds and dated recordings. It is not verified in game for live patch 0.5.1.1. Loot, costs and times may have changed.

0.5.0 / cb4f600 (2026-10-22) · Sources checked 14 November 2026

Open source

All related map references (3)

Each map point shows its own meaning and precision.

Up the Stream · Source objective reference 1 · 131, 142 Up the Stream · Source objective reference 2 · 131, 142 Up the Stream · Source objective reference 3 · 130, 142

Not yet established

The reviewed text describes the mission goal, not a complete arrival-to-handover route.
Current-patch verification, sufficient map positions and visual step evidence are missing.

All sources & coverage