The Mine Safety and Health Administration (MSHA), a division of the U.S. Dept. of Labor, provides a complete listing of hazard classifications for dams.
MSHA provides these hazard classifications for the purpose of assessing potential impact should dam failure occur. These hazard classifications also serve another purpose:
"To establish appropriate criteria for use in the design and operation of the facility. Thus, more conservative design and operations criteria apply as the potential for loss of life or property damage from failure increases.” – MSHA.gov
MSHA also indicates that more subsurface exploration and material property testing is normally performed for a facility with high hazard potential than one with low hazard potential.
Utilizing Hazard Classifications
Since MSHA allows facility managers to assess "potential" impacts of a failure, this helps avoid loss of operational safety on site. MSHA classifications adapt to the existing design of the specific facility and through proper assessment and implementation, focus attention on full phase operations and employee safety while performing daily tasks.
Guidelines to Dam Safety
Dam safety begins with design engineers whose task is to optimize safety in structural drawings of a new dam. Construction of proposed dams are massive projects that require strict attention to compliance regulations such as those found within MSHA and safe construction principles.
Among the guidelines to dam safety in construction and operation, dam design for proposed or existing mining facilities, require expertise and certification by hydrological design, engineering and construction professionals.
Large dams provide hydroelectric power. Smaller dams may be constructed for the purpose of flood control in flood plain areas or as retention basins to prevent soil erosion, depending on the circumstances and design sizes required. Still other dams serve mining operations and for runoff retention purposes.
Basic guidelines for dam safety are authorized on a federal and state level. Federal Guidelines for Dam Safety includes hazard classifications similar to MSHA, which is based on potential for worst case failure conditions and consequences of failure should a dam failure occur. In the U.S., there were over 8,000 deaths and 200 dam failures during the 20th century, punctuating further the need for federal and state safety guidelines.
Under federal dam safety guidelines, provisions for consideration include:
Note that on a state-by-state basis, each state may have dam safety regulations in addition to those at the federal level. This is usually due to topographical differences existing in a particular state.
In order to maintain dam safety at mining facilities, regular inspections are required to prevent fatalities, property damage and property loss in entirety. Under the MSHA Dam Safety Program, dams and impoundments are evaluated from measurable downstream distances.
Relationship of Dams and Impoundments in Mining Operations
Large mining operations utilize the expertise of a diverse group of engineers to design methods to store water for mining use and mining waste impounds.
As stated by MSHA, water used in mining operations require runoff control to "to prevent flooding of mine facilities. Runoff control is also necessary to "collect and prevent sediment from running off the mine property."
All mining materials impounded as liquid, solid or water waste may be a hazard to miners, should the holding dam fail for any reason. All dams used in mining operations must comply with federal and state regulations from startup design to construction and daily operations to avoid risk to workers, mine property and surrounding properties, rivers, lakes and streams, beyond the mining property lines.
Importance of MSHA Safety and Training
Mine owners live daily with potential risk. However, mine owners practice due diligence with regard to reducing risk and adhering to federal and state mining safety compliance regulations.
In order to ensure safety at all levels of mining operations, MSHA safety can be readily adapted through safety training programs and regular refresher training courses for employees and management.
An investment in a MSHA Safety Program results in a return in risk reduction and a safer workplace.