If you have recently received an Abandoned Mine Lands (AML) hazard notice, you may be wondering exactly what AML hazard fencing is and why it is important.
Until recently, prospectors were allowed to leave a mine site without being required to leave the property in a safe condition. These aging abandoned mines may contain sheer drop-offs, unstable earth, abandoned equipment, trapped gasses, deep standing water, and more. With no posted warning signs or barriers required, abandoned mines became a hazard across the country. Each year, individuals in the United States are injured or killed in these mining hazards due to falls, entrapment, drowning, and more. To help prevent accidents, owners of abandoned mine land are required to erect and maintain AML hazard notices and barricades.
To aid in this safety effort, several state and federal organizations identify and monitor abandoned land mines. Landowners are asked to proactively manage AML hazard fencing around known abandoned mine lands, even if they have not received a notice, to help protect the public.
WHAT IS AML HAZARD FENCING?
AML hazard fencing refers to posted signage, barricades, and/or fences erected around abandoned mine land areas and access points. These barricades and signs are intended to help protect individuals from undue access and injury.
For ordered AML Hazard fencing required by a state or federal program, there are minimal requirements for these signs and barricades that must be followed depending on access point type and hazard level. Individuals receiving an AML Hazard Notice will be provided a certain amount of time (typically between 60-180 days, depending on the hazard level) to erect this fencing and send proof of completion. In addition, landowners are required to maintain these notices and barricades to ensure safety.
COMMON ABANDONED MINE LAND HAZARDS
What’s so dangerous about abandoned mine land hazards? When mines are constructed, they have safety precautions in place that are intended only for the short term. When these mines were abandoned, vertical openings were often left uncovered, support structures were removed or left to rot, and safety systems such as ventilation and water-pumping equipment were removed.
There are several types of hazards that may be present at an abandoned mine site depending on the size, scope, equipment, and location of the mine.
- Adits, Declines, and Shafts. Open adits and shafts are the most common type of hazard in the Western United States. Adits tunnel into the ground horizontally, declines tunnel in at an angle, and shafts tunnel down vertically. These diggings can be unstable and there may not be much indication the hazard is there until someone is very close to it.
- Trenches and Pits. Trenches and Pits are common in historical mining districts. Many times the walls are unstable; these areas need to be fenced to keep people out and warn people that a hazard is in the area.
- Water Hazards. The largest cause of death in abandoned mines in the United States is water. Many abandoned mines become flooded, leaving water that may be dangerously deep and cold, as well as having slippery walls, steep drop-offs, and other hazards.
- Gasses & Oxygen Deficiency. Mines are also at risk of accumulating pockets of deadly gasses such as carbon monoxide, methane, or even pockets of still air that have little oxygen concentration.
- Cave-Ins. Even active mines are at risk of cave-ins, but for abandoned mines, this risk increases. Over time, bedrock can become increasingly unstable due to weathering, blasting, water accumulation, and other factors. This makes even casual exploration dangerous in or around an abandoned mine.
- Highwalls. Underground mines are not the only AML areas that contain risks. Open pits and quarries also contain risks. Highwalls are vertical or near-vertical edges of these pits or quarries. These areas can be prone to collapse, which makes them dangerous to climb on or near.
AML HAZARD FENCING SERVICES
If you’d like to learn more about AML hazard fencing requirements or services, please reach out to Rangefront’s mining services experts today.
ABOUT THE AUTHOR
BRIAN GOSS
President, Rangefront Mining Services
Brian Goss brings over 20 years of experience in gold and mineral exploration. He is the founder and President of Rangefront, a premier geological services and mining consulting company that caters to a large spectrum of clients in the mining and minerals exploration industries. Brian is also a director of Lithium Corp. (OTCQB: LTUM), an exploration stage company specializing in energy storage minerals and from 2014 to 2017, he fulfilled the role of President and Director of Graphite Corp. (OTCQB: GRPH), an exploration stage that specialized in the development of graphite properties. Prior to founding Rangefront, Brian worked as a staff geologist for Centerra Gold on the REN project, as well as various exploration and development projects in the Western United States and Michigan. Brian Goss holds a Bachelor of Science Degree with a major in Geology from Wayne State University in Michigan.
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