OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Search conducted by: S. Michele Manning

Page 1 of 2

COALEX STATE INQUIRY REPORT – 92

October 20, 1987

Clint Milne

Mining and Minerals Division

New Mexico Energy and Minerals Department

525 Camino de los Marquez

Santa Fe, New Mexico 87501

TOPIC: SMALL AREA EXEMPTIONS

INQUIRY: 30 CFR Sec. 816.46(e) creates an exemption from the requirement that an operator 

construct siltation structures if, among other things, the disturbed drainage area is "small". Has 

Congress or OSM attempted to define the meaning of the work "small" as used in this context?

SEARCH RESULTS: Section 816.46 of the federal regulations requires that treatment 

facilities be constructed to establish and maintain sediment control on a permitted area. Under 

Sec. 816.46(e), exemptions to this requirement may be granted if (1) the disturbed drainage area 

within the total disturbed area is "small"; and (2) the operator can demonstrate that siltation 

structures and other sediment control measures are not necessary for drainage from the area to 

meet effluent limitations established under Sec. 816.42 and applicable state and Federal laws. 

This "small area exemption" is not specifically enunciated in SMCRA, therefore, no pertinent 

legislative history on the meaning of the work "small" is available. OSM included this exemption 

when it promulgated the original regulations in 1978 concerning the use of siltation structures to 

control surface runoff. These regulations were authorized by Sec. 515(b)(10)(B) of SMCRA, 

which requires the operator to minimize the disturbances to the prevailing hydrologic balance by 

"conducting surface coal mining operations so as to prevent...additional contributions of 

suspended solids to streamflow, or runoff outside the permit area" and to "construct any siltation 

structures...prior to commencement of surface coal mining operations." From this language, it is 

apparent that Congress left the development of specific siltation control measures to the 

discretion of the regulatory authority.

The language of Sec. 816.46(e) has not been altered since it was originally developed by OSM in 

1978. In the preamble to the final rules as published in 1979, OSM made no attempt to 

specifically define "small"; instead, it appears that the determination of whether an area is 

"small" is to be left to the discretion of the regulatory authority.

This assertion is bolstered by OSM's response to comments made on this section. In the 1979 

preamble, OSM considered modifying the exemption to require that the area be "small relative to 

the size of the ponds which would have to be constructed to comply with Sec. 814.46", but 

rejected such a modification, noting:
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Search conducted by: S. Michele Manning

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"The Office considers this modification to the proposed exemption to be unnecessary, because 

the language of the more general exemption provides greater latitude for a determination of what 

is small' and also meets the intent of the Office to recognize that, on isolated corners of 

operations, the building of sedimentation ponds may not be necessary to meet effluent limitations 

or water quality requirements and may create more deleterious effects to the local hydrologic 

system than the mining disturbance itself." (44 FR 14901, 15152 (1979))

As was noted earlier, the language of this exemption has not been altered since its adoption. 

Thus, the determination of whether an area is "small" is left to the discretion of the regulatory 

authority.

An earlier COALEX Report dealt with the meaning of a related topic: the definition of "small 

depression" as it is found at 30 CFR Sec. 816.102. A copy of the Report and its documentation 

are attached.

ATTACHMENTS

A. 44 FR 15152 (1979). 

B. COALEX STATE INQUIRY REPORT - 83, "Small depressions".