REP50071

• Permit No: C1981044
• IBM Index Class Name: Report
• Doc Name: REGULATION OF COAL MINE SUBSIDENCE IN COLO
• Permit Index Doc Type: SUBSIDENCE REPORT
• Media Type: D
• Archive: No

~ Chapter 75
THE REGULATION OF COAL MINE SUBSIDENCE IN COLORADO III 'll'IIIIIIIII III
999
James A. Pendleton, Ph.D.
Mined Land Reclamation Division,
Department of Natural Resources, State of Colorado
'bstract. In response to Public Law 95-87
iM RA ,Colorado promulgated regulations
_overning the mining of Coal. These regulations
require the prediction, monitoring and mitigation
of "material damage" caused by subsidence. All
permitted underground coal mines within Colorado
ave approved subsidence programs. Preliminary
~nitoring results indicate the subsidence
~:echanical predictions have been sufficiently
accurate to preclude material subsidence damage.
.~e State of Colorado has developed a practical
approach to regulating subsidence, which stresses
monitoring verification of predicted subsidence
phenomena. However, shortcomings exist in our
rbility to precisely predict the secondary
consequences of subsidence, including effects to
•uctures, the hydrologic balance and the
_..oironment. lack of accuracy in predicting these
secondary consequences results in uncertainty,
necessitating conservatism in permitting. To
.:void increasingly stringent permit restrictions,
future research should emphasize the secondary
:onsequences of subsidence.
Introduction
Amendments to the Rules, including the subsidence
regulations were adopted by the Board in August of
1981. These regulations require the prediction,
monitoring and mitigation of "material damage"
caused by subsidence.
This paper describes the state regulations
pertaining to subsidence control. Examples are
cited from approved permits within the state.
Performance of the approved subsidence programs
are related for the past five years.
Technological short-comings and research
objectives are identified.
Colorado Subsidence Regulation
Two sections of the regulations of the Colorado
Mined Land Reclamation Board for coal mining are
dedicated to the regulation of subsidence. Rule
2.05.6(6) "Subsidence Survey, Subsidence
Monitoring and Subsidence Control Plan", presents
the requirements for the preparation of
subsidence-related portions of permit
applications. Rule 4.20, "Subsidence Control",
presents the subsidence performance standards
which all mines must satisfy.
The Legislature of the State of Colorado
adopted House Bill 1223, "The Colorado Surface
::oal Mining Reclamation Act" (The State Act), in
1979. This Act provided for the creation of a
state regulatory program as accommodated within
public Law 95-87, "The Surface Mining Control and
Reclamation Act of 1977" (SMCRA). Section
;4-33-121(2)(a) of the Colorado Revised Statutes
(CRS) and Section 516(b) of Public Law 95-87,
identically require the underground coal mine
operator to "Adopt measures consistent with known
technology in order to prevent subsidence causing
material damage to the extent technologically and
economically feasible, maximize mined stability,
and maintain the value and reasonably foreseeable
use of such surface lands, except in those
instances where the mining technology used
requires planned subsidence in a predictable and
controlled manner..."
On July 23, 1980, the Colorado Mined Land
7eclamation Board adopted regulations to
administer and enforce the State Act.
The requirements of the various sections of
Rule 2.05.6(6) will be discussed in detail
hereafter. Rule 4.20, the "Subsidence Control"
performance standards, are analogous to Sections
817.121 through 817.126 of the regulations of the
U. S. Office of Surface Mining Reclamation and
Enforcement (OSM). These performance standards
address the notification of potentially affected
property owners and residents, the protection of
surface owner's property and property values, and
the provision of buffer zones. Rule 4.20.4, which
addresses Buffer Zones, includes provisions for
protection of water bodies and impoundments,
aquifers which serve as water supply to public
water systems and public buildings, such as
"churches, schools, hospitals, courthouses and
government offices." The final paragraph of Rule
4.20.4 provides the Division the authorization to
"suspend underground coal mining under urbanized
areas, cities, towns and communities, and adjacent
to industrial and commercial buildings, major
impoundments or permanent streams, if imminent
danger is found to inhabitants."
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