[Federal Register: August 13, 2010 (Volume 75, Number 156)]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
DEPARTMENT OF LABOR
Mine Safety and Health Administration
30 CFR Parts 56 and 57
Metal and Nonmetal Dams
AGENCY: Mine Safety and Health Administration, Labor.
ACTION: Advance Notice of Proposed Rulemaking (ANPRM).
SUMMARY: Dam failures at metal and nonmetal mines have exposed miners
to life-threatening hazards. The Mine Safety and Health Administration
(MSHA) is reviewing its existing metal and nonmetal standards for dams.
The Agency is concerned that some dams pose hazards because they are
not designed, constructed, operated, and maintained to accepted dam
safety practices. MSHA is considering approaches to better protect
miners from the hazards of dam failures and is soliciting information
to help determine how best to proceed.
DATES: Comments must be received by midnight Eastern Daylight Saving
Time on October 12, 2010.
ADDRESSES: Comments must be identified with ``RIN 1219-AB70'' and may
be sent to MSHA by any of the following methods:
(1) Federal E-Rulemaking Portal: http://www.regulations.gov. Follow
the on-line instructions for submitting comments.
(2) Electronic mail: zzMSHA-Comments@dol.gov. Include ``RIN 1219-
AB70'' in the subject line of the message.
(3) Facsimile: 202-693-9441. Include ``RIN 1219-AB70'' in the
subject line of the message.
(4) Regular Mail: MSHA, Office of Standards, Regulations, and
Variances, 1100 Wilson Boulevard, Room 2350, Arlington, Virginia 22209-
(5) Hand Delivery or Courier: MSHA, Office of Standards,
Regulations, and Variances, 1100 Wilson Boulevard, Room 2350,
Arlington, Virginia. Sign in at the receptionist's desk on the 21st
MSHA will post all comments on the Internet without change,
including any personal information provided. Comments can be accessed
electronically at http://www.msha.gov under the ``Rules and Regs''
link. Comments may also be reviewed in person at the Office of
Standards, Regulations, and Variances, 1100 Wilson Boulevard, Room
2350, Arlington, Virginia. Sign in at the receptionist's desk on the
MSHA maintains a list that enables subscribers to receive e-mail
notification when the Agency publishes rulemaking documents in the
Federal Register. To subscribe, go to http://www.msha.gov/
FOR FURTHER INFORMATION CONTACT: Patricia W. Silvey, Director, Office
of Standards, Regulations, and Variances, MSHA, at
email@example.com (E-mail), 202-693-9440 (Voice), or 202-693-9441
MSHA's database contains information on nearly 2000 dams at metal
and nonmetal mines. Mine operators have constructed these structures
for various purposes, such as disposing of tailings or mine waste,
processing minerals, treating or supplying water, and controlling run-
off and sediment. Although many of these dams are designed,
constructed, operated, and maintained according to accepted dam safety
practices, others are not and dam failures and near failures continue
Since 1990 to the present, MSHA investigated dam failures at metal
and nonmetal mines in virtually every region of the country and at
small and large operations. Failures or near failures have occurred at
copper, phosphate, sand and gravel, trona, gypsum, and limestone mines,
Failures have damaged property and equipment, but no deaths or
serious injuries have occurred. Examples of dam failures include:
A 1990 failure of a 100-foot high dam at a limestone mine
in Puerto Rico released over 10 million gallons of water and tailings.
The failure flooded eight lanes of a major highway, depositing tailings
up to eight feet thick. The dam failed about 2 a.m. when no miners were
present. The mine operator did not use an engineer to design the dam;
several design and construction deficiencies, such as poor compaction,
steep slopes, and absence of internal drains, contributed to the
A 70-foot high tailings dam failed at an andesite quarry
in Wisconsin in 1992, tearing apart a railroad track and leveling a
power line at the mine. The dam failed at 3 a.m. when no miners were
present. The dam was not designed by an engineer. After a slope failure
in 1987, the mine operator installed instruments in the dam to monitor
internal water pressures. Pressures beyond a certain level would lead
to structural instability. In the 18 months before the 1992 failure,
however, the operator checked the instruments only twice. A combination
of steep slopes and high internal water pressure contributed to the
In 1997, a dam at an Arizona copper mine released tailings
for over a half mile downstream and to depths of 30 feet. Four miners,
one in a haul truck, one in a bulldozer, and two in a pickup truck,
were carried down-slope with the slide. One miner injured his back
running from the pickup but the others were not injured. The dam was
designed by an engineer; however, the mine operator's rate of placement
of waste rock on top of the tailings created pressures that contributed
to the failure.
In August 2002, a 450-foot section of dam failed at a sand
and gravel mine in Georgia, sending a wave of water and tailings
through the shop area. The 30-foot high dam failed shortly after 8 p.m.
The wave of water and tailings moved a scraper, backhoe and front-end
loader, which were parked in the area. Three miners, near the shop, saw
the dam failing and escaped in a pickup truck. The dam, built without
being designed by an engineer, had a weak foundation, among other
In 2004, a dam failure at a sand and gravel mine in
California released over 200 million gallons of water and tailings,
inundating a hydraulic excavator in an adjacent pit. The failure
occurred shortly after 6 p.m., at the start of the maintenance shift.
About 15 minutes before the failure, the excavator operator had gone
home and a bulldozer operator had parked his machine on the top of the
dam. A miner who lubricated the equipment was driving into the pit when
he noticed the rising water, halted his truck, and backed up the access
road. The dam was not properly designed. The investigation revealed
that the design of the dam failed to include an evaluation of the
foundation and embankment material strengths, and stability analyses to
verify that the slopes of the dam would have adequate factors of
MSHA investigators have found that design, construction, operation,
or maintenance deficiencies have contributed to failures of dams at
metal and nonmetal mines and exposed miners to hazards.
Since the early 1970's, Congress has enacted laws to create a
national program to reduce the risks of dam failures. The Federal
Emergency Management Agency (FEMA) is charged with administering the
national dam safety program and has issued a series of Federal
Guidelines for Dam Safety (Guidelines) (http://www.fema.gov/library/
The Guidelines address, among other things, practices and
procedures for the design, construction, operation, and maintenance of
all types of dams. In the Guidelines, FEMA recommends that dams:
Be designed by a competent engineer;
Be constructed under the general supervision of a
competent engineer knowledgeable about dam construction;
Be inspected and monitored at frequent intervals by a
person trained to recognize unusual conditions; be inspected by a
competent engineer with knowledge of dam safety at a frequency
consistent with the dam's hazard potential; and
Have an emergency action plan, if dams are classified as
having high or significant hazard potential in the event of failure.
Every two years, MSHA reports on the status of its dam safety
program to FEMA, which then sends Congress an evaluation of each
Federal agency's program and how it complies with the Guidelines. FEMA
has recommended, in biennial reports to Congress and in meetings of the
Interagency Committee on Dam Safety, that MSHA promulgate standards to
encompass all aspects of design, construction, and inspection for dams
at metal and nonmetal mines.
The existing requirements for dams at metal and nonmetal mines, 30
CFR 56.20010 and 57.20010, are derived from the Metal and Nonmetallic
Mine Safety Act of 1966. The standards state: ``If failure of a water
or silt retaining dam will create a hazard, it shall be of substantial
construction and inspected at regular intervals.'' The standards
promulgated for coal mines under the Federal Coal Mine Health and
Safety Act of 1969 were similar, but specified that the mine operator
inspect the dams
at least once per week and record inspection findings.
The requirements for coal mines were revised in 1975 after the
Buffalo Creek dam failure. For dams which can present a hazard or are
of a certain size, the existing standards require a coal mine operator
Have a registered professional engineer certify the dam's
Develop plans for the design, construction, maintenance,
and abandonment of the dam and have the plans approved by MSHA;
Have a qualified person inspect the dam weekly;
Have instrumentation monitored weekly;
Correct any hazardous conditions and make required
Submit an annual report with a registered, professional
engineer's certification that construction, operation, and maintenance
of the dam have been in accordance with approved plans.
II. Key Issues on Which Comment Is Requested
MSHA is asking interested parties to comment on measures to assure
that mine operators design, construct, operate and maintain dams to
protect miners against the hazards of a dam failure.
MSHA seeks comments on the questions below. If a commenter refers
to a particular dam as an example, please identify the mine, or provide
the number of miners and the mine's commodity. Also, include the dam's
storage capacity, height, and hazard potential and characterize its
complexity. Provide enough detail with the comments that the Agency can
understand the issues raised and give them the fullest consideration.
Comments should include alternatives, rationales, benefits to miners,
technological and economic feasibility, impact on small mines, and
supporting data. Please include any information that supports your
conclusions and recommendations: Experiences, data, analyses, studies
and articles, and standard professional practices.
1. MSHA is seeking information concerning current dam safety
practices at metal and nonmetal mines. What measures do mine operators
currently take to design, construct, operate, and maintain safe and
effective dams? What measures do mine operators currently take to
safely abandon their dams? For mine operators with dams, please provide
2. MSHA is required to inspect every mine in its entirety, which
includes dams of all sizes and hazard potential. A common approach for
dam safety is to have tiered requirements based on a dam's size and
hazard potential. How should MSHA determine safety requirements based
on a dam's size and hazard potential? Please include specific
recommendations and explain your reasoning.
3. What non-Federal authority regulates the safety of dams at metal
and nonmetal mines in your state, territory, or local jurisdiction?
Please discuss the specific requirements, including the principles that
they address. If possible, please provide information about relevant
non-federal dam safety requirements through a hyperlink or other means.
4. What records should be kept of activities related to the safety
of dams? Please be specific and include your rationale. What records
should be provided to miners if hazardous conditions are found?
Design and Construction of Dams
MSHA's existing standards do not include specific requirements for
design of dams. MSHA found that inadequate design contributed to some
of the metal and nonmetal dam failures. In responding to the following
questions, please discuss how any requirements should vary according to
the size or hazard potential of a dam, and why.
5. How should mine operators assure that dams are safely and
effectively designed? Please suggest requirements that MSHA should
consider for safe design of dams. Please be specific and include your
6. Please suggest requirements for review of dam designs by mine
operators and MSHA and include your rationale for specific
recommendations and alternatives.
7. With new standards, operators may need to evaluate and upgrade
existing dams. Please elaborate on how the safety of existing dams
should be addressed.
8. MSHA's existing standards for dams at metal and nonmetal mines
do not address whether a dam is constructed as designed. What measures
are necessary to ensure that mine operators construct dams as designed?
9. How should MSHA verify that dams have been constructed as
designed? Please explain your rationale.
Operation and Maintenance of Dams
MSHA's existing standards do not contain specific requirements
addressing the operation and maintenance of dams.
10. What should a mine operator do to operate and maintain a safe
dam? How should MSHA verify that dams are safely operated and
maintained? Please be specific.
MSHA's existing standards require dams to be inspected at regular
intervals if failure would create a hazard. Inspections can identify
hazardous conditions, allowing a mine operator to take corrective
action to prevent a failure. The Agency will be referring to two types
of inspections in this document, ``routine'' and ``detailed.'' Mine
operators should perform frequent, routine dam inspections, which may
include monitoring instrumentation, to identify unusual conditions and
signs of instability. Personnel with more specialized knowledge of dam
safety should conduct detailed inspections to identify less obvious
problems and evaluate the safety of the dam. Detailed inspections,
occurring less often, would include an examination of the dam and a
review of the routine inspections and monitoring data. The Guidelines
recommend that inspection personnel be qualified for their level of
responsibility and trained in inspection procedures.
11. What measures should mine operators take to assure that dams
are adequately inspected for unusual conditions and signs of
12. How often are routine inspections of dams conducted? How often
should they be conducted? What determines the frequency? Who conducts
the routine inspections? Please be specific and include your rationale.
13. Instruments, such as weirs, provide information on the
performance of a dam. How frequently should mine operators monitor dam
instrumentation? Please provide your rationale.
14. What information should be documented during routine dam
inspections? Please provide your rationale.
15. Does a competent engineer inspect your mine's dam? If so, at
what frequency? Please explain the rationale for these inspections and
what is evaluated.
16. How often should detailed inspections be conducted? Please
include your rationale.
17. What information and findings should be documented during
detailed dam inspections? Please be specific and include your
18. How should MSHA verify that mine operators conduct routine and
detailed inspections? Please explain how your suggestion would work.
Qualifications of Personnel
A mine operator is responsible for the design, construction,
operation, and maintenance of dams. For an effective dam safety
program, an operator must use personnel who are knowledgeable about dam
19. What qualifications do mine operators currently require of
persons who design, inspect, operate, and manage dams? In what
capacities are engineers used? Please be specific in your response.
20. The Guidelines recommend that dams be designed by competent
engineers. What specific qualifications or credentials should persons
who design dams possess? Please include your rationale.
21. The Guidelines recommend that a dam be constructed under the
general supervision of a competent engineer knowledgeable about dam
construction. What specific qualifications or credentials should a
person have who verifies that a dam is being constructed as designed?
Please provide your rationale.
22. What training should personnel receive who perform frequent,
routine inspections and who monitor instrumentation at dams? In your
response, please suggest course content and the frequency of the
training, including the rationale for your recommendations.
23. What qualifications or credentials should be required of
persons who perform detailed inspections to evaluate the safety of a
dam? Please be specific and include your rationale.
Abandonment of Dams
24. Some regulatory authorities require that dam owners obtain
approval of a plan to cap, breach, or otherwise safely abandon dams.
What actions should mine operators take to safely abandon dams? Please
include specific suggestions and rationale.
25. How can MSHA verify that a mine operator has safely abandoned a
MSHA seeks information to assist the Agency in deriving the costs
and benefits of any regulatory changes for dams at metal and nonmetal
mines. In answering the following questions, please indicate the dam's
storage capacity, height, and hazard potential and characterize the
complexity of each dam referenced. Also, please include the state where
each dam is located, and the number of employees at the mine.
26. What are the costs of designing a new dam? Please provide
details such as hours, rates of pay, job titles, and any contractual
services necessary. How often is the design of an existing dam changed?
What are the costs of a redesign?
27. What are the costs of constructing a dam? Please provide
details based on: Size of dam; labor costs, including hours, rates of
pay, job titles; costs of equipment and materials; and any contractual
28. Please describe the oversight you provide during dam
construction to assure it complies with the design plan. How much does
it cost per year per dam for oversight and quality control? What
special knowledge, qualifications, or credentials do you require of
those who provide oversight?
29. How often do you add height to an existing dam or modify it in
some other way? Who supervises the design and construction of these
modifications, for example, a professional engineer, competent
engineer, contractor, etc? Please be specific and provide rationale for
your answer. How much does it cost? Please provide details such as
labor costs, including hours, rates of pay, job titles, and costs of
equipment and materials and any contractual services necessary.
30. How much does it cost per year per dam for routine inspections?
If you incur separate costs for monitoring instrumentation, how much is
that cost? How often do you have a detailed inspection conducted? How
much does it cost per year for these inspections?
31. Does the state or local jurisdiction in which you operate
require you to use a professional engineer? If so, when is a
professional engineer specifically required? (If you have dams in more
than one state please identify which states require a professional
engineer and which do not).
32. What are the costs associated with training personnel who
conduct frequent, routine inspections and monitor instrumentation at
33. What costs are involved in capping, breaching, or otherwise
properly abandoning a dam? Please provide details of your experience
and what was involved when you properly abandoned a dam. Describe any
impact of a properly abandoned dam.
34. What are the costs to a mine operator if a dam fails? Please
characterize other impacts such as loss of life, environmental damage,
35. Do you have insurance against a dam failure? If so, please
specify cost and coverage. Does the insurance carrier require the use
of a professional engineer for specific dam activities? If a
professional engineer is not required, does the insurance carrier give
a discount if one is used? Does your insurance company have any other
requirements related to dam safety?
36. What quantifiable and non-quantifiable costs and benefits for
the downstream community are involved when a dam is properly designed
and constructed? In addition, MSHA welcomes comments on other relevant
indirect costs and benefits.
Dated: August 9, 2010.
Joseph A. Main,
Assistant Secretary of Labor for Mine Safety and Health.
[FR Doc. 2010-19960 Filed 8-12-10; 8:45 am]
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