Eliminating Hazards at Abandoned Mines Will 

Take a Long Time

Although federal agencies are working to remove hazards 

and to close abandoned mines, it will take decades to 

complete this work. As many as half a million abandoned 

mines are believed to exist, and the location of many more is 

still unknown. Usually, sites have no signage at all to warn 

people about their presence or their dangers.

Hazards at Abandoned Mines Are Not 

Under Control

These dangers are real and could kill or injure not only you, 

but also family, friends, and others who attempt to rescue you.

1. You Fall to Your Death Down a Shaft. You’re 

walking, off a trail, and have no idea that under your feet is a 

mine shaft hundreds of feet deep. Or you see a mine opening 

and figure you’ll just step inside to check it out. Either way, 

what is beneath your feet can quickly disappear under your 

weight and vibrations. STAY ON MARKED TRAILS. 

STAY OUT OF MINES.

5. You Can’t Find Your Way Out. Because mines can 

have so many openings leading in different directions, it is 

easy to become lost and disoriented very soon after entering 

a mine. Backtracking is an option, yet one wrong turn could 

prove fatal. If flashlights or other artificial light sources fail 

or break, you will be in utter darkness. Even expert cavers 

have lost their way in these conditions. STAY OUT.

6. While Above Ground, You Plunge Over an 

Unexpected Cliff (Highwall), You Are Buried Alive 

Under a Collapsing Highwall, You Fall Into/Drown 

in an Open Pit. Highwalls are vertical cliffs of earth and 

debris left over from mining near the surface. Highwalls are 

unstable, prone to collapse, and extremely dangerous. If you 

approach one from the top in a motorized vehicle, chances 

are that you will not see the cliff until it is too late. Open pits 

on the other side of these cliffs are often filled with water 

and harmful chemicals. Drowning in water-filled pits and 

quarries is the most common cause of death in abandoned 

mines. STAY ON MARKED TRAILS.

Other dangers include exposure to radioactive gas 

and toxic chemicals, confrontations with wildlife 

dwelling in mines, and injury from collapsing surface 

structures and equipment. Any water in abandoned 

mines could be toxic—do not drink it.

2. You Are Crushed by a Cave-In. Wood, metal, and rock 

supports in mines—and especially around mine openings—

rot and decay, leaving unsafe structures. Mine shafts, and 

horizontal openings, are dangerous pathways where ceilings 

and floors could give way just because of your presence. 

STAY OUT.

3. You Are Killed by Explosives Left Behind. Even a 

small vibration can trigger undetonated/unstable explosives, 

which are frequently left behind in mines. STAY OUT.

4. You Breathe in Deadly Gases or Run Out of Oxygen. 

Lethal gases (methane, carbon monoxide, hydrogen sulfide, and 

toxic levels of carbon dioxide) can accumulate in underground 

passages—even close to entrances. When you breathe these 

gases, your muscles stop responding normally. Your thinking 

becomes clouded, and you are unable to help yourself. This is 

followed by loss of consciousness, and death. There typically 

is no smell or other warning sign that these gases are present. 

Even pockets of air with extremely low oxygen levels can rob 

you of your ability to react. STAY OUT.
The following portal is sponsored by federal, state, and local 

partners to raise awareness about Abandoned Mine Lands: 

http://abandonedmines.gov

For additional information about Abandoned Mine Lands, 

visit the following websites:

Federal Programs

National Park Service

http://nature.nps.gov/geology/aml/index.cfm

Bureau of Land Management

http://www.blm.gov/wo/st/en/prog/more/

Abandoned_Mine_Lands.html

U.S. Forest Service

http://www.fs.fed.us/geology/aml.html

Office of Surface Mining

http://www.osmre.gov/index.shtm

Environmental Protection Agency

http://www.epa.gov/superfund/programs/aml/

State Programs

http://www.naamlp.net

Why Are There Abandoned Mines?

Abandoned mines are what is left over from mining activities in 

the distant past. Back then, mine operators could simply walk 

away from a mine without removing safety or environmental 

hazards. Today, federal and state laws require that mine 

operators make mine sites safe before abandoning them. 

How Dangerous Are Abandoned Mines?

Every year, many people are killed or hurt at abandoned mine 

sites. In 2000–2013 alone, 381 people were killed; 152 people 

suffered broken bones and other injuries. Across the country, 

abandoned mines exist in every state. Even a mine that was 

“safe” last year could be deadly today due to deteriorating 

conditions.

The leading cause of death at abandoned mines is drowning 

in water-filled pits and quarries. Steep, slippery walls make 

it difficult to get out of the water. Old machinery and other 

hazards beneath the water can injure or trap you. 

The second most common cause of death and injury is falling 

into vertical underground mine openings. These openings 

can be hundreds of feet deep. Often they are not visible but 

concealed by dirt, rock, mine debris, and water. Unstable 

ground or decaying timbers around mine openings can simply 

drop out from beneath your feet.

Don’t Be Fooled!

The lack of a sign does NOT mean 

that a mine is safe!

Produced by the BLM National Operations Center, Denver, CO

BLM/WO/GI-13/009+3720

P-416

Dangers at 

Abandoned 

Mines

 ...can kill you