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u:s. DEPARTMENT OF THE INTERIO 

OFRCEOFSURFACE~Gr-~~~~~N~-~~:~ 

RECLAMATION AND ENFORCEMENT 362 

Subl-et Number: 

REG--14 

DIRECTIVES SYSTEM O.t~; 

. 7/9/37 

Interpretation of Initial Program and Indian Lands 

tions Conce n n · d 1i 

l, PtmPOSE. '11lis directive provides guidance to clarify the regulatory 

requ1rements concerning the stabilization of rills and gullies on 

Indian lands (25 CFR Part 216) and on lands subject to the Federal 

initial program regulations (Subchapter .B of 30 CFR Olapter VII). 

2 , DEFINITI CNS , None • 

3, POLICY/PROCEDURES. 

The backfilling and grading regulations at 25 CFR 216.105(i) (Indian 

lands) and 30 CFR 715.14 (i) (initial program sites) require that when 

rills and gullies deeper than nine inches form in areas that have 

been regraded and have had the topsoil replaced, but where vegetation 

has not yet been established, the permittee fill, grade, or otherwise 

stabilize the rills and gullies and reseed or replant the area 

a=rding to 25 CFR 216.110 or 30 CFR 715.20, as appropriate. Also, 

the rules specify that rills and gullies of lesser size must be 

stabilized if the erosion channels will disrupt the approved 

postmining land use or will result in additional erosion. 

The revegetation regulations at 25 CFR 216.110 (Indian lands) and 30 

CFR 715.20 (initial program sites) require the establishment of.a 

diverse, effective, permanent vegetative cover, capable of 

stabilizing the soil surface with respect to erosion and supportive 

of the approved postmining land use, on the entire permit area. 

Considered in conjunction with each other, these rules require that 

rills and gullies which form on regraded and topsoiled areas on 

Indian lands or initial program sites be filled, gra1ed, or otherwise 

stabilized unless they have naturally stabilized and will not. 

interfere with the postmining land use. Areas containing rills and 

gullies must also meet all applicable requirements of 25 CFR 216.110 

or 30 CFR 715.20 concerning surface stabilization and revegetation 

before full release of bond or operator liability can occur. 

Where vegetation sufficient to control overall erosion on the site 

has not yet been established, the presence of active rills and 

gullies constitutes a violation only when the rills and gullies are 

greater than nine inches in depth, or where. they would interfere with 

the postmining land use, or where they are of such areal extent as to 

preclude prompt future stabilization by further natural vegetative 

developnent. Operators should of course be encouraged to initiate 

appropriate soil conservation measures before erosion cccurs to this 

degree. 

7!22/86 
In evaluating rill and gully conditions, individuals must 

distinguish between active and inactive channels. Active rill and 

gully channel erosion is characterized by: 

(1) vertical or near vertical channel sides with the soil 

exposed; 

(2) overhanging banks or associated bank failures (unstabilized slumping); 

(3) continuing channel expansion or extension headward (uphill), outward (lateral), or downward (depth); 

(4) occurrence in the channel of raised clumps of soil 

(pedestals) containing plants whose roots are exposed around 

the edge of the pedestal; 

(5) temporary establishment of plants on channel sides because 

the plants have been undermined and translocated by erosional activities; 

(6) exposure of root crowns of plants along channel walls; 

(7) continuing downchannel deposition of eroded materials; and 

(B) lack of litter or organic matter accumulation in the channel. 

Characteristics of inactive erosional channels include: 

(1) rounding of channel sides; 

(2) discontinuance of channel expansion or extension (headward, 

outward, or downward); 

(3) extensive permanent establishment of vegetation on the sides 

and bottom of the channel; 

(4) lack of unanchored clumps of soil and vegetation that have 

fallen from the channel sides; 

(5) discontinuance of downchannel deposition of eroded materials; 

(6) establishment of a permanent vegetative cover on areas of 

erosional deposition; and 

(7) accumulation of litter and organic matter in the channel. 

) 
Observation of a rill or gully is not itself evidence that erosion is 

presently occurring or that site utility is being impaired. Where an 

erosional channel appears stabilized, based upon an evaluation of the 

channel characteristics discussed ~e. and the channel does not 

interfere with the postmining land use, the permittee should be advised 

to monitor the site for ·any change in status, but should not be required 

to take any corrective action. Inspectors shall also monitor such rills 

and gullies for any change in status. In general, if a channel displays 

both active and inactive characteristics, it should be considered active 

(and hence unstabilized). 

The remedial action specified for any rill or gully violation shall 

clearly allow use of the environmentally least disruptive method of 

stabilization consistent with the approved postmining land use. One 

example of a remedial measure other than regrading that may be acceptable is the application of heavy mulch or fiber mats to stabilize channels 

which do not interfere with the postmining land use. 

4. REPORI'ING RmUIREMENTS. None. 

5. REFEREN:ES. None. 

6. EFFECT ON Ol'HER IXX:UMENTS. Supersedes memorandum dated May 28, 1986, 

from the Deputy Director, Operations and Technical Services to the 

Assistant Directors, Field Operations ccncerning rills and gullies. 

7. EFFECTIVE DATE. Upon Issuance. 

8. CONTACT. Chief, Division of Regulatory Programs, (202) 343-5351.