OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 1 of 7

COALEX COMPARISON REPORT - 45

January, 1986

TOPIC: TOPSOIL SUBSTITUTES*

* This report is based on the most recent documents identified in the COALEX file. A state may 

have additional or revised rules or procedures not contained in the COALEX file.

SEARCH RESULTS:

Sec. 515(b)(5) of the Federal Surface Mining Control & Reclamation Act (SMCRA) requires the 

removal, segregation, and preservation of topsoil from the area to be mined. However, other 

strata may be similarly removed, segregated, and preserved if the topsoil is of insufficient 

quantity or of poor quality, or if other strata can be shown to be more suitable for sustaining 

vegetation.

Given this statutory framework, questions arise as to when topsoil substitutes can be used, what 

criteria for using substitutes is mandated by federal regulation, and what criteria is left to the 

discretion of the states. This Report focuses on the federal regulations and the various state 

equivalents pertaining to soil substitutes.

Federal Regulations

OSM's permanent program regulations include the general provisions of SMCRA providing for 

the removal, storage, and replacement of topsoil or a substitute. The regulations also include 

direction as to when a topsoil substitute may be used and what tests must be performed.

OSM defines topsoil as "the A & E soil horizon layers of the four master soil horizons." The 

federal regulations promulgated pursuant to SMCRA list four major soil horizons. The A horizon, 

often called the surface soil, is the part of the soil in which organic matter is most abundant. 

Leaching of soluble or suspended particles is typically the greatest in the A horizon. The layer 

near the surface and below the A horizon is known as the E horizon. An E horizon is most 

commonly differentiated from the A horizon by a lighter color and generally has measurably less 

organic matter. It can be differentiated from the B horizon by color of higher value or lower 

chroma, or by a coarser texture. Immediately below the E horizon is the B horizon, commonly 

known as the subsoil. This layer commonly contains more clay, iron, and aluminum than the 

other three horizons. The deepest layer of the soil profile, known as the C horizon, consists of 

loose material or weathered rock that is relatively unaffected by biologic activity. (30 CFR Sec. 

701.5) If topsoil of sufficient quality and quantity is available, it must be removed, segregated, 

and replaced in accordance with 30 CFR Sec. 816.22 or 817.22. However, situations may arise 

in which the available topsoil is too thin or of poor quality for sustaining revegetation. 

Recognizing these problems, the re= gulations provide for the use of selected overburden 

materials as a substitute for or as a supplement to existing topsoil. (30 CFR Sec. 816.22(b), 

817.22(b))

Before removing the topsoil and the substitute materials to be used, the operator must 

demonstrate to the regulatory authority that the resulting medium is equal to, or more suitable 
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 2 of 7

for sustaining vegetation than, the existing topsoil and is the best available in the permit area. 

(30 CFR Secs. 816.22(b) and 817.22(b)) If use of a substitute or supplement is approved, the 

alternative material should be treated in accordance with topsoil handling requirements found in 

30 CFR Secs. 816.22 and 817.22.

Insufficient Quality

The factors which an operator is required to evaluate to demonstrate the suitability of a soil 

substitute are found in the reclamation plan requirements of 30 CFR Secs. 780.18(b)(4) and 

784.13(b)(4). Several tests are mandated by federal regulation: analysis of the thickness of soil 

horizons, total depth, texture, percent coarse fragments, pH, and areal extent of the different 

kinds of soils. (Id.) Other tests may be performed if deemed "necessary and desirable" by the 

regulatory authority; including field-site trials or greenhouse tests. (Id.) Tests for net acidity or 

alkalinity, phosphorus and potassium were deleted from the final rules, but may be conducted 

according to local conditions. (46 FR 22092, 22093 (1983))

Interpretive rules found at 30 CFR Secs. 816.200 and 817.200 clarify when and how these tests 

should be conducted. Both the existing topsoil and the proposed substitute must be tested in 

order to show the advantage of using the substitute and the results must be certified by an 

approved laboratory. Sources where the analysis, trials, and tests may be obtained are also 

listed. (30 CFR Sec. 816.200(c)(1), 817.200(c)(1)) If the operator can demonstrate through soil 

survey or other data that the topsoil is insufficient and substitute material will be used, only the 

substitute must be analyzed under 780.18(b)(4) and 784.13(b)(4).

If surface soils have not already been mapped, an operator may request the Soil Conservation 

Service to conduct a soil investigation. Other data may also be accepted or required which has 

been collected according to National Cooperative Soil Survey Standards. (45 FR 39446, 39447 

(1980))

No regulatory provisions were identified at the federal level that specifically indicated the 

number or frequency of soil samples that may be necessary on a mine site prior to approval of a 

topsoil substitute. However, several states have adopted rules requiring a certain number of soil 

samples. This information, taken from a April, 1984 survey conducted by the Interstate Mining 

Compact, is summarized in Table 1.

Insufficient Quantity

The federal regulations provide guidelines for thin topsoil situations. If the topsoil is less than six 

inches thick, the operator may remove the topsoil and the unconsolidated materials directly 

below and treat the mixture as topsoil. (30 CFR Secs. 816.22(a)(2) and 817.22(a)(2)) This six 

inch requirement is a minimum, so additional material may be required to be saved if necessary 

to ensure soil productivity. (44 FR 15138, 15140 (1979)) However, this minimum does not apply 

if more than six inches of topsoil is available; in that situation all existing topsoil must be 

removed. (46 FR 22092, 22094 (1983))
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 3 of 7

State Regulations

A search was conducted of the states listed with COALEX to determine what topsoil substitution 

tests are required. In addition, results of a survey conducted by the Interstate Mining Compa= ct 

Commission on topsoil and overburden handling procedures were utilized.

Many of the states identified use the same criteria for approval as is found in the federal 

regulations. Thus, selected overburden materials may be used as a topsoil substitute or 

supplement if the operator can demonstrate to the regulatory authority that the resulting soil 

medium will be equal to or more suitable than the existing topsoil for sustaining revegetation. 

However, the tests which must be conducted to demonstrate the suitability of the substitute vary 

from state to state.

Seven states (Missouri, Kentucky, Virginia, Louisiana, Maryland, Mississippi, and Arkansas) use 

the mandatory tests found in earlier versions of the federal regulations. (See 30 CFR Secs. 

816.22(e)(I) and 817.22(e)(I) (1982)) These tests are: pH, net acidity or alkalinity, phosphorous, 

potassium, and texture class. In addition, other tests may be required by the regulatory authority 

(see Table 2).

Three states reported that substitution is not utilized. In Kansas, there is no overburden 

substituted for the A or B horizons; in Iowa, none is substituted due to the geology.

Pennsylvania's regulatory requirements for surface coal mining do not allow for topsoil 

substitutes. However, subsoil substitutes are allowed under the provisions found in Appendix A1.

The remaining fifteen states use a variety of tests to determine the adequacy of topsoil 

substitutes. These tests are listed on Table 3. All states require testing for pH, while seven or 

more require testing for texture class, potassium, phosphorous, net acidity/alkalinity, electrical 

conductivity and sodium absorption ratio. In Wyoming, revegetation test plots for subsoil are 

mandatory. (Wyoming Land Quality Regulations, Sec. 2c(2))

Oklahoma's proposed topsoil substitute plan requires a variety of tests according to which strata 

are to be used. A number of tests are required for all strata, but additional tests are to be 

performed on subsoil and geologic strata. (See Appendix A-2)

ATTACHMENTS:

A. 44 FR 15138 (1979).

B. 45 FR 39446 (1980).

C. 48 FR 22092 (1983).

D. Wyoming Land Quality Division Regulations, Sec. 2c(2) (1980).

APPENDIX A

A-1 Pennsylvania Narrative on Subsoil Substitutes

A-2 Oklahoma Narrative on Topsoil Substitutes
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 4 of 7

TABLE 1: OVERBURDEN CORE SAMPLES REQUIRED

(IMCC Survey, 4/24/85)

(Reformatted from original)

ALABAMA

1 per 40 acres - mines less than 100 aces.

1 per 80 acres - mines greater than 100 acres.

ILLINOIS

Site specific - generally 2 per pit; 1 per 80 acres for prime farmland.

IOWA

Site specific.

INDIANA

Site specific.

KANSAS

Site specific.

KENTUCKY

Site specific - generally 1 per 1/4 mile in Eastern Kentucky, 1 per « mile in Western Kentucky.

MISSOURI

Site specific - minimum of 1 per permit area.

NEW MEXICO

1 per 150 acres; minimum of 3 per permit.

NORTH CAROLINA

Site specific.

NORTH DAKOTA

Site specific.

OHIO

Site specific.

OKLAHOMA

a) No apparent limiting factors and moderate level of soil complexity:

 1) less than 2 acres - none

 2) 2-25 acres - 1

 3) 15-75 acres - 2

 4) greater than 75 acres - 3

b) One or more apparent limiting factors and moderate level of soil complexity:

 1) less than 2 acres - none

 2) 2-10 acres - 1

 3) 10-50 acres - 2
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 5 of 7

 4) 50-120 acres - 3

 5) greater than 120 acres - 4.

TEXAS

Approximately 1 per 500 acres.

UTAH

4 boreholes per section for ACR.

16 per section 1 year prior to mining.

WYOMING

Number should adequately characterize each mapping unit; suggested that at least one 

sample be taken for each series found. Recommended intensities:

a) 5% of mine area (or 40-60 acres) - 3 samples

b) -5% of mine area (40-160 acres) - 2 samples

c) 2% of mine area (40 acres) - 1 sample.

TABLE 2: STATES FOLLOWING 30 CFR SEC. 816.22(e)(1)

(Reformatted from original)

MISSOURI

10 CSR 40-3.030(2)(E)

KENTUCKY

405 KAR 16:050E

VIRGINIA

Coal Surface Mining Reclamation Regs., V816.22(e)

LOUISIANA

La. Surface Mining Regulations, Statewide Order 29-0-1 Sec. 216.22

MARYLAND 

Md. Admin. Code, Tit. 8, Sec. 08.13.09.02

MISSISSIPPI

Surface Coal Mining & Reclamation Regs., Sec. 216.22

ARKANSAS

Surface Coal Mining & Reclamation Code, Sec. 816.22

STATES NOT USING SUBSTITUTION

IOWA

None due to geology.

KANSAS

No overburden substituted for A or B horizons.
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 6 of 7

PENNSYLVANIA

Topsoil substitutes not allowed; subsoil substitutes or supplements allowed.

TABLE 3: TESTS USED TO DETERMINE THE ADEQUACY OF TOPSOIL SUBSTITUTES

(Reformatted from original)

ALABAMA

ph; Potassium; Phosphorous Net Acidity/Alkalinity; % Coarse Fragments

Other: Weathering ability; Calcium, Sulfur (Total or Pyritic)

ALASKA

pH, Texture Class; % Coarse Fragments

Other: Thickness of soil horizons; Chemistry areal extent of soils; Mineralogy of fine earth 

fraction

COLORADO

pH; Potassium; Phosphorous; Net Acidity/Alkalinity; Electrical Conductivity; Sodium 

Absorption Ratio

ILLINOIS

pH; Texture Class; Potassium

Other: P1, P2, NNP

INDIANA

pH; Texture Class; Potassium; Phosphorous; Net Acidity/Alkalinity; Nitrogen; % Organic 

Matter; CaCo3 Equivalent/Deficiency

Other: % Pyritic Sulfur

MONTANA

pH; Texture Class; Net Acidity/Alkalinity; Electrical Conductivity; Sodium Absorption Ratio

MISSOURI

pH; Texture Class; Potassium; Phosphorous; Electrical Conductivity; Sodium Absorption 

Ratio; % Organic Matter; CaCo3 Equivalent/Deficiency

Other: Calcium, Magnesium

NEW MEXICO

pH; Texture Class; Net Acidity/Alkalinity; Electrical Conductivity; Sodium Absorption Ratio; 

CaCo3 Equivalent/Deficiency

Other: Saturation, Boron, Selenium, Molybdenium, Copper

NORTH DAKOTA

pH; Texture Class; Potassium; Phosphorous; Electrical Conductivity; Sodium Absorption 

Ratio; Nitrogen; % Organic Matter; Water Holding Capacity
OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT

U.S. Department of the Interior

Research conducted by: Betty S. Chambers and S. Michele Manning Page 7 of 7

OHIO

pH; Texture Class; Potassium; Phosphorous; % Coarse Fragments; % Organic= Matter; 

CaCo3 Equivalent/Deficiency

OKLAHOMA

pH; Texture Class; Potassium; Phosphorous; Electrical Conductivity; Nitrogen; % Coarse 

Fragments; CaCo3 Equivalent/Deficiency

Other: See Appendix A-2

TEXAS

pH; Texture Class; Net Acidity/Alkalinity; Electrical Conductivity; Sodium Absorption Ratio

UTAH

pH; Texture Class; Net Acidity/Alkalinity; Electrical Conductivity; Sodium Absorption Ratio; 

Nitrogen; % Coarse Fragments 

Other: Saturation, Selenium, Boron, Molybdenium, Arsenic

WEST VIRGINIA

pH; Texture Class

Other: Nutrient Content

WYOMING

pH; Texture Class; Potassium; Phosphorous; Net Acidity/Alkalinity; Electrical Conductivity; 

Sodium Absorption Ratio; Nitrogen; % Coarse Fragments; % Organic Matter; Water Holding 

Capacity

Other: Revegetation test plots for subsoil required; Selenium, Boron, Arsenic

ATTACHMENTS:

A. COALEX COMPARISON REPORT - 37.

B. Short excerpts of state regulations referencing coal exploration.