N.J. Admin. Code § 7:9A-5.3

Current through Register Vol. 56, No. 21, November 4, 2024

Section 7:9A-5.3 - Terminology required for soil logs

(a) A soil log shall be prepared for each soil profile pit or soil boring. The soil profile characteristics listed in 7:9A-5.2(g) shall be described using the terminology specified in (b) through (h) below.

(b) Depth and thickness of each district soil horizon or substratum shall be reported in inches. A distinct soil horizon or substratum is any soil horizon or substratum which differs from horizons or substrata above or below it in color, texture, coarse fragment content, mottling, structure or consistence.

(c) Color shall be described using the Munsell system of classification which includes a descriptive color name such as "strong brown" or "pale red", together with an alpha-numeric designation of hue, value and chroma such as "7.5 YR 5/6" or "2.5 YR 6/2". When mottling is encountered, report the dominant or background color and the mottle colors.

(d) Texture shall be reported as the name of the appropriate textural class which is shown on the USDA textural triangle, Figure 3 of Appendix A, determined based upon the relative proportions of sand, silt and clay in that portion of the soil which excludes the coarse fragment. Texture shall be estimated in the field by feel, or determined by textural analysis as prescribed in 7:9A-6.3.

(e) The volume percentage of coarse fragments shall be estimated in the field visually using volume percentage estimation charts provided in Figure 4 of Appendix A. Coarse fragments which are rounded or subrounded in shape shall be classified based upon size, as indicated in (e)1 through 3 below. In the case of shale, slate, or other thin rock fragments, the rock type and the average length and thickness of the rock fragments shall be reported.

1. "Gravel" means a rock fragment from two millimeters (0.1 inches) to 76 millimeters (three inches) in diameter;

2. "Cobble" means a rock fragment from 76 millimeters (three inches) to 254 millimeters (10 inches) in diameter; and

3. "Stone" means a rock fragment greater than 254 millimeters (10 inches) in diameter.

(f) When mottling is observed, the abundance, size, and contrast of the mottles shall be reported using the following terminology:

1. Abundance shall be estimated visually, by using the volume percentage charts provided in Figure 4 of Appendix A, to estimate the percentage of the exposed surface which is occupied by mottles. Abundance of mottles shall be classified as follows:

i. Mottles are "few" when less than two percent of the exposed surface is occupied by mottles;

ii. Mottles are "common" when from two percent to 20 percent of the exposed surface is occupied by mottles; and

iii. Mottles are "many" when more than 20 percent of the exposed surface is occupied by mottles.

2. Size shall be classified based on the estimated average longest dimension of the mottles, as follows:

i. Mottles are "fine" when they are less than five millimeters in size;

ii. Mottles are "medium" when they are from five to 15 millimeters in size; and

iii. Mottles are "course" when they are greater than 15 millimeters in size;

3. Contrast shall be described as follows:

i. Mottles are "faint" when they may be distinguished only on close examination;

ii. Mottles are "distinct" when they are readily seen but not prominent; and

iii. Mottles are "prominent" when they are obvious and one of the outstanding features of the soil horizon.

(g) Soil structure shall be described using the following terms which refer to the shape of the natural soil aggregates:

1. Structure is "spheroidal" when the aggregates are more or less equi-dimensional and lack sharp corners, sharp edges or well-defined faces. This term includes crumb and granular structure as defined by the USDA;

2. Structure is "subangular blocky" when the aggregates are more or less equi-dimensional and possess well-defined flat or somewhat curved faces, but lack sharp corners or edges;

3. Structure is "angular blocky" when the aggregates are more or less equi-dimensional in shape and possess well-defined flat or somewhat curved faces, sharp corners and sharp edges;

4. Structure is "prismatic" when the aggregates have one axis distinctly longer than the other two and are oriented with the long axis vertical;

5. Structure is "platy" when the aggregates have one axis distinctly shorter than the other two and are oriented with the short axis vertical. Soil horizons with platy structure generally show numerous well-defined horizontal structural faces and lack well defined vertical structural faces;

6. Structure is "massive" when the soil consists of a dense, compact mass showing no recognizable natural aggregates or structural faces; and

7. Structure is "single grain" when the soil consists of loose individual sand grains which lack cohesion and are not bound together into recognizable soil aggregates.

(h) Soil consistence shall be described using the following terminology which refers to the ease with which a soil clod or aggregate may be crushed with the fingers in either the dry or moist condition.

1. In the dry soil condition, soil consistence is characterized as:

i. "Loose" when the soil is non-coherent;

ii. "Soft" when the soil mass breaks to a powder of individual grains with slight pressure;

iii. "Slightly hard" when the soil mass is easily broken between thumb and forefinger;

iv. "Hard" when the soil mass can be broken in the hands without difficulty, but is barely breakable between thumb and forefinger; and

v. "Very hard" when the soil mass can be broken in the hands with difficulty, but is not breakable between thumb and forefinger.

2. In the moist soil condition, soil consistence is characterized as:

i. "Loose" when the soil is non-coherent;

ii. "Friable" when the soil material crushes easily between thumb and forefinger;

iii. "Firm" when the soil material crushes under moderate pressure between thumb and forefinger;

iv. "Very firm" when the soil material is barely crushable under strong pressure between thumb and forefinger; and

v. "Extremely firm" when the soil material cannot be crushed between thumb and forefinger, but can only be broken apart bit by bit.

3. For any moisture condition, soil consistence is characterized as "cemented" when the soil mass is brittle and hard, and cannot be broken by hand.

N.J. Admin. Code § 7:9A-5.3