Nine miners survived the July 2002 Quecreek inundation after a rescue involving drilling, pumping, communications, and a capsule brought down from the surface. The investigation also exposed a lasting information problem: an incomplete historical map had been treated as a reliable boundary of abandoned workings.
The account below follows the MSHA investigation report and its later addendum. Times are the local times recorded in the report. This is a historical explanation, rather than instructions for mine operations or rescue.
How the miners became trapped
At about 8:45 p.m. on July 24, 2002, water broke into the working face of the 1-Left section at Quecreek #1 mine in Somerset County, Pennsylvania. The water came from the abandoned Harrison No. 2 mine. Nine miners on the affected section could not get out because water blocked their route. Seven miners on another section and two outby miners escaped.
The underground elevations mattered. Water filled lower workings and cut off the escape path while the trapped crew reached higher ground. Reading the event only as “water entered a tunnel” misses why a route could become unusable before the entire mine was flooded.
A rescue in stages
On a narrow screen, scroll the table sideways. Keyboard users can focus the table region and use the arrow keys.
| Local date and time | Event | Why it mattered |
|---|---|---|
| July 24, about 8:45 p.m. | Water inundation begins. | Nine miners become trapped on 1-Left. |
| July 25, morning | A 6.5-inch borehole reaches the section; miners tap on the drill steel. | The surface receives and acknowledges a sign of survivors. |
| July 25, evening | Drilling begins on a 30-inch rescue hole. | A larger route is needed for extraction while pumping continues. |
| July 27, 10:13 p.m. | The rescue hole reaches the mine. | The extraction opening is established. |
| July 27, 10:53 p.m. | Communications equipment is lowered through the smaller hole. | Rescuers learn all nine miners are alive. |
| July 28, 12:55–2:45 a.m. | The first through last miners reach the surface in MSHA's rescue capsule. | All nine are recovered alive. |
MSHA describes entrapment lasting approximately 76 to 78 hours, reflecting different extraction times. The often-used “77 hours” is a shorthand for that interval. The smaller borehole, larger rescue opening, and water removal served different roles in a coordinated effort.
What the investigation found
MSHA identified the use of an undated, uncertified map that did not show the complete final Harrison No. 2 workings as the primary cause. That information fed an inaccurate depiction on Quecreek's own maps. The report identified the unavailability of a certified final map in Pennsylvania's repository as the root cause.
Its analysis also considered whether changing water or roof conditions should have warned the crew. Investigators concluded that potential warning signs were obscured by conditions previously encountered in the mine. That finding matters: the lesson cannot fairly be reduced to a claim that workers simply ignored an obvious approaching flood.
For readers examining the report's maps, compare the map's date, purpose, surveyed extent, and source. A boundary on a drawing may represent the extent of available information rather than a verified physical stopping point. The distinction between “mapped” and “complete” is central to this case.
What later records added
MSHA's later investigation addendum describes documents examined in July 2004, including maps and correspondence about final workings. A 1964 letter described plans to provide a final blueprint, and two detailed maps together appeared to show the entire older mine.
The addendum discusses fragmented filing and the difficulty of locating records. It concludes that, without someone who knew the maps and their whereabouts, even possession of the documents would not have made retrieval likely. Preserve that distinction: information can exist in a collection while remaining unavailable to the person making a consequential decision.
Read the rescue and the prevention lesson together
- Preserve provenance: keep a record's source, date, scope, and uncertainty attached to it.
- Make records retrievable: preservation needs indexing, ownership, and a workable response to requests.
- Resolve consequential uncertainty: an incomplete map deserves explicit treatment in qualified planning.
- Separate history from hindsight: use investigation findings to distinguish what was known then from what became known later.
The survival of all nine miners and the records failure are both essential parts of the story. Read the report and addendum together for their evidence and qualifications. For a different example of planning how critical information reaches people, see emergency communications continuity.