Tables: Soil Testing Criteria
Back to source | Source PDF | Structured table records
Table fragments retain their source context. Refer to the original page for layout, figures, merged headings and notes.
1. Table 1
BMP 2024, Ch 12, p. 2
| Section No. |
Contents |
Page No. |
| 1 |
Methods for Identifying HSGs and Soil Series: |
3 |
| 1a |
HSG and Soil Series Designations from the NRCS Soil Survey |
4 |
| 1b |
Default HSG and Soil Series Designations for Runoff Computations and the NJGRS Spreadsheet |
5 |
| 1c |
Hydrologic Soil Group Testing Procedures |
7 |
| 1d |
Seasonal High Water Table Location |
11 |
| 1e |
Perched Water Table Requirements |
13 |
| 2 |
Soil Tests for Stormwater Management BMPs: |
14 |
| 2a |
Soil Testing Requirements for Infiltration BMPs |
15 |
| 2b |
Soil Testing Requirements for Non-Infiltration BMPs with a required separation from the SHWT |
22 |
| 2c |
Soil Log Requirements |
22 |
| 3 |
Soil Hydraulic Conductivity Testing: |
27 |
| 3a |
Acceptable Soil Hydraulic Conductivity Test Methods |
27 |
| 3b |
Hydraulic Conductivity Testing in Fractured Bedrock |
27 |
| 4 |
Construction and Post-Construction Oversight and Soil Hydraulic Conductivity Testing: |
28 |
| 4a |
Construction and Post-Construction Oversight Requirements |
28 |
| 4b |
Post-construction Hydraulic Conductivity Testing |
28 |
| 5 |
Determination of the Input Parameters for Groundwater Mounding Analyses |
29 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
| Section No. | Contents | Page No. |
| --- | --- | --- |
| 1 | Methods for Identifying HSGs and Soil Series: | 3 |
| 1a | HSG and Soil Series Designations from the NRCS Soil Survey | 4 |
| 1b | Default HSG and Soil Series Designations for Runoff Computations and the NJGRS Spreadsheet | 5 |
| 1c | Hydrologic Soil Group Testing Procedures | 7 |
| 1d | Seasonal High Water Table Location | 11 |
| 1e | Perched Water Table Requirements | 13 |
| 2 | Soil Tests for Stormwater Management BMPs: | 14 |
| 2a | Soil Testing Requirements for Infiltration BMPs | 15 |
| 2b | Soil Testing Requirements for Non-Infiltration BMPs with a required separation from the SHWT | 22 |
| 2c | Soil Log Requirements | 22 |
| 3 | Soil Hydraulic Conductivity Testing: | 27 |
| 3a | Acceptable Soil Hydraulic Conductivity Test Methods | 27 |
| 3b | Hydraulic Conductivity Testing in Fractured Bedrock | 27 |
| 4 | Construction and Post-Construction Oversight and Soil Hydraulic Conductivity Testing: | 28 |
| 4a | Construction and Post-Construction Oversight Requirements | 28 |
| 4b | Post-construction Hydraulic Conductivity Testing | 28 |
| 5 | Determination of the Input Parameters for Groundwater Mounding Analyses | 29 |
2. Table 2
BMP 2024, Ch 12, p. 3
| Part |
Addendum Contents |
Page No. |
| A1 |
Percolation Test |
32 |
| A2 |
Tube Permeameter Test |
37 |
| A3 |
Basin Flooding Test |
44 |
| A4 |
Modified Basin Flooding Test |
45 |
| A5 |
Single Ring Infiltration Test |
47 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
In addition, the chapter includes an Addendum on the testing procedures listed in the table below:
| Part | Addendum Contents | Page No. |
| --- | --- | --- |
| A1 | Percolation Test | 32 |
| A2 | Tube Permeameter Test | 37 |
| A3 | Basin Flooding Test | 44 |
| A4 | Modified Basin Flooding Test | 45 |
| A5 | Single Ring Infiltration Test | 47 |
## General Notice
It is the responsibility of the company or persons performing or witnessing subsurface investigations and soil hydraulic conductivity tests to comply with all applicable Federal, State and local laws and regulations governing occupational safety, including, but not limited to, the requirements such as N.J.A.C. 7:9A-5.2(e)3 and Occupation Safety and Health Administration 1926, Subpart P. All soil profile pits, soil borings and soil hydraulic conductivity tests, along with any associated documentation, shall be conducted under the direct supervision of a licensed New Jersey professional engineer. During all subsurface investigations and soil test procedures, adequate measures shall be taken to ensure personnel safety and prohibit unauthorized access to the excavations at all times. Entering a soil pit excavated below the water table can be extremely dangerous and should be avoided unless the pit is relatively shallow and the sides of the pit have been stepped and sloped to eliminate the likelihood of sudden and severe cave-in of the pit.
## Section 1: Methods for Identifying HSGs and Soil Series
3. Table 3
BMP 2024, Ch 12, p. 5
| Summary by Map Unit - Middlesex County, New Jersey [NJ023] |
|
|
|
| Summary by Map Unit - Middlesex County, New Jersey [NJ023] |
|
|
|
| Map unit symbol |
Map unit name |
Rating |
Acres in A01 |
| FodB |
Fort Mott loamy sand, 0 to 5 percent slopes |
A |
27.8 |
| GarnB |
Galloway loamy sand, 0 to 5 percent slopes |
A/D |
0.2 |
| GarnkB |
Galloway loamy sand, clayey substratum, 0 to 5 percent slopes |
A/D |
7.4 |
| LakB |
Lakahurst sand, 0 to 5 percent slopes |
A |
22.4 |
| WakN |
Manshawkin musk, 0 to 2 percent slopes, frequently flooded |
A/D |
8.5 |
| HSG |
Pits, sand and gravel |
A |
9.8 |
| HW |
Pits, clay |
A |
3.6 |
| Totals for Area of Interest |
|
|
79.7 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
A close up of the lower right legend is provided in Figure 12-1b below. The column titled "Map unit name" contains the information on the soil series and the soil types for each soil unit depicted as a shape on the map in Figure 12-1a. HSG information is shown under column titled "Rating". The two areas highlighted in gray, within the white ovals, are those map units identified by the red rectangle for which HSG and soil series have not been determined. The soils in the undetermined HSG and soil series may be determined by the methods in Subsections 1b and 1c, which are discussed on Pages 5 and 7, respectively. Information on dual-rated soils shown above and on the following page, i.e., those with a rating of 'A/D,' is provided on Page 7.
Figure 12-1b: NRCS Web Soil Survey Summary by Map Unit Legend
| Summary by Map Unit - Middlesex County, New Jersey [NJ023] | | | |
| --- | --- | --- | --- |
| Summary by Map Unit - Middlesex County, New Jersey [NJ023] | | | |
| Map unit symbol | Map unit name | Rating | Acres in A01 |
| FodB | Fort Mott loamy sand, 0 to 5 percent slopes | A | 27.8 |
| GarnB | Galloway loamy sand, 0 to 5 percent slopes | A/D | 0.2 |
| GarnkB | Galloway loamy sand, clayey substratum, 0 to 5 percent slopes | A/D | 7.4 |
| LakB | Lakahurst sand, 0 to 5 percent slopes | A | 22.4 |
| WakN | Manshawkin musk, 0 to 2 percent slopes, frequently flooded | A/D | 8.5 |
| HSG | Pits, sand and gravel | A | 9.8 |
| HW | Pits, clay | A | 3.6 |
| Totals for Area of Interest | | | 79.7 |
## Subsection 1b: Default HSG and Soil Series Designations
Where HSG information from the NRCS Web Soil Survey or a published survey is either unavailable or inconsistent with conditions in the field, the runoff computations for pre- and post-developed drainage area conditions may be based upon default HSGs. These default HSGs are shown in Table 12-1 below for drainage areas within and outside New Jersey's coastal plain, which is depicted in the graphic provided as Figure 12-2 on the next page. Additionally, the NJDEP Bureau of GIS website allows the user to locate an address to obtain information regarding the physiographic province in which a project is located. Use the link provided below:
https://gisdata-njdep.opendata.arcgis.com/datasets/20377d0dc1fe41f1ab2d9d0897844441_20/explore.
4. Table 12-1: Default Hydrologic Soil Group for Runoff Computations
BMP 2024, Ch 12, p. 5
| Site Condition |
Site Location (see Figure 12-2) |
|
|
In Coastal Plain |
Outside Coastal Plain |
| Pre-construction |
HSG A |
HSG B |
| Post-construction |
HSG D |
HSG D |
Source context and notes
Where HSG information from the NRCS Web Soil Survey or a published survey is either unavailable or inconsistent with conditions in the field, the runoff computations for pre- and post-developed drainage area conditions may be based upon default HSGs. These default HSGs are shown in Table 12-1 below for drainage areas within and outside New Jersey's coastal plain, which is depicted in the graphic provided as Figure 12-2 on the next page. Additionally, the NJDEP Bureau of GIS website allows the user to locate an address to obtain information regarding the physiographic province in which a project is located. Use the link provided below:
https://gisdata-njdep.opendata.arcgis.com/datasets/20377d0dc1fe41f1ab2d9d0897844441_20/explore.
If the designer engineer does not wish to utilize these assumed hydrologic soil groups, a process is outlined in the remainder of this chapter to establish the HSG based on a site-specific investigation.
Table 12-1: Default Hydrologic Soil Group for Runoff Computations
| Site Condition | Site Location (see Figure 12-2) | |
| --- | --- | --- |
| | In Coastal Plain | Outside Coastal Plain |
| Pre-construction | HSG A | HSG B |
| Post-construction | HSG D | HSG D |
Once the default HSG is selected, in accordance with the table above, the default soil series shown in Table 12-2 may be used in the NJGRS for groundwater recharge calculations.
5. Table 12-2: Default Soil Series for NJGRS Recharge Computation
BMP 2024, Ch 12, p. 6
| HSG |
Soil Series Name |
| A |
Fort Mott |
| B |
Nixon |
| C |
Readington |
| D |
Any soil series that results in zero annual recharge |
Source context and notes
Source revision: March 2024.
Figure 12-2: Physiographic Provinces of NJ
[Figure: img-1.jpeg (original PDF, p. 6)](SOURCE.pdf#page=6)
Image modified from the New Jersey Geological Survey Information Circular, "Physiographic Provinces of New Jersey, 2006" and used with permission.
Table 12-2: Default Soil Series for NJGRS Recharge Computation
| HSG | Soil Series Name |
| --- | --- |
| A | Fort Mott |
| B | Nixon |
| C | Readington |
| D | Any soil series that results in zero annual recharge |
6. Table 12-3: Example 1 - Soil Explorations vs. Map Unit Size
BMP 2024, Ch 12, p. 9
| Map Unit Size |
Number of Soil Profile Pits |
Number of Soil Borings |
| 0.45 ac |
1 |
1 |
| 1.9 ac |
1 |
4 |
| 2.6 ac |
1 + 1 = 2 |
4 + 2 = 6 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Table 12-3: Example 1 - Soil Explorations vs. Map Unit Size
| Map Unit Size | Number of Soil Profile Pits | Number of Soil Borings |
| --- | --- | --- |
| 0.45 ac | 1 | 1 |
| 1.9 ac | 1 | 4 |
| 2.6 ac | 1 + 1 = 2 | 4 + 2 = 6 |
## Depth of Soil Profile Pits and Boring:
The determination of the soil HSG is based upon the depth to restrictions (i.e., the depth to the SHWT and soil morphological characteristics which restrict the vertical movement of water including, but not limited to, abrupt textural boundaries, fragipans, dense materials, bedrock and ortstein horizons and the hydraulic conductivity of the most restrictive soil horizon above either the restriction or the SHWT. The presence and depth of these restrictions must be included in the soil log of both the soil profile pits and the soil borings. Soil profile pits and soil borings performed for the purpose of determining HSG must extend at least 40 inches below existing grade, except when the SHWT is at a depth of 24 inches or less, the exploration may be terminated before excavation to the depth of 40 inches below existing grade and the soils are classified as HSG D. If the same soil profile pit or soil boring will also be used for the test of soil hydraulic conductivity, the depth of the exploration shall follow the requirements set forth in Subsection 2a on Page 15. Examples of the required depth for HSG soil exploration are in Table 12-4 below.
Table 12-4: Example 2 – HSG Soil Exploration Required Depth Determinations
7. Table 12-4: Example 2 – HSG Soil Exploration Required Depth Determinations
BMP 2024, Ch 12, p. 9
| Elevation |
Example 2-A |
Example 2-B |
Example 2-C |
| Ex. Grade (EG) = |
EL. 11 |
EL. 9 |
EL. 9 |
| 40 in. Below EG= |
EL. 7.66 |
EL. 5.66 |
EL. 5.66 |
| SHWT = |
SHWT was not encountered |
EL. 7.5 |
EL. 6.5 |
| Required Elevation of Soil Pit or Boring Excavation = |
Answer: EL. 7.66
SHWT was not within 24 inches below the existing grade. The depth is required down to at least 40 inches below the existing grade. |
Answer: EL. 7.5
SHWT was within 24 inches below the existing grade. The soil is designated as HSG D soil. The excavation may be terminated before to the depth of 40 inches below the existing grade. |
Answer: EL. 5.66
SHWT was not within 24 inches below the existing grade. The depth is required down to at least 40 inches below the existing grade. |
Source context and notes
| 2.6 ac | 1 + 1 = 2 | 4 + 2 = 6 |
## Depth of Soil Profile Pits and Boring:
The determination of the soil HSG is based upon the depth to restrictions (i.e., the depth to the SHWT and soil morphological characteristics which restrict the vertical movement of water including, but not limited to, abrupt textural boundaries, fragipans, dense materials, bedrock and ortstein horizons and the hydraulic conductivity of the most restrictive soil horizon above either the restriction or the SHWT. The presence and depth of these restrictions must be included in the soil log of both the soil profile pits and the soil borings. Soil profile pits and soil borings performed for the purpose of determining HSG must extend at least 40 inches below existing grade, except when the SHWT is at a depth of 24 inches or less, the exploration may be terminated before excavation to the depth of 40 inches below existing grade and the soils are classified as HSG D. If the same soil profile pit or soil boring will also be used for the test of soil hydraulic conductivity, the depth of the exploration shall follow the requirements set forth in Subsection 2a on Page 15. Examples of the required depth for HSG soil exploration are in Table 12-4 below.
Table 12-4: Example 2 – HSG Soil Exploration Required Depth Determinations
| Elevation | Example 2-A | Example 2-B | Example 2-C |
| --- | --- | --- | --- |
| Ex. Grade (EG) = | EL. 11 | EL. 9 | EL. 9 |
| 40 in. Below EG= | EL. 7.66 | EL. 5.66 | EL. 5.66 |
| SHWT = | SHWT was not encountered | EL. 7.5 | EL. 6.5 |
| Required Elevation of Soil Pit or Boring Excavation = | Answer: EL. 7.66
SHWT was not within 24 inches below the existing grade. The depth is required down to at least 40 inches below the existing grade. | Answer: EL. 7.5
SHWT was within 24 inches below the existing grade. The soil is designated as HSG D soil. The excavation may be terminated before to the depth of 40 inches below the existing grade. | Answer: EL. 5.66
SHWT was not within 24 inches below the existing grade. The depth is required down to at least 40 inches below the existing grade. |
Note: "Ex." Denotes Existing and "EL." Denotes Elevation
8. Table 8
BMP 2024, Ch 12, p. 11
| Determination of Hydrologic Soil Group Worksheet |
|
|
|
|
|
| Determining No. of Test Pit for HSG |
|
|
|
Requirements |
|
| Unknown Mapping Unit No. |
Size of Mapping Unit (acre) |
# of Soil Profile Pit(s) Required |
# of Soil Boring(s) Required |
1. a mapping unit of less than 0.5 acre, a minimum of one soil profile pit and one soil boring shall be conducted within that mapping unit.
2. a minimum of one soil profile pit and four soil borings shall be conducted within each soil mapping unit of 0.5 acre or more and less than or equal to 2 acres, as shown on the NRCS Web Soil Survey.
3. a mapping unit larger than 2 acres within the limits of the overall site, a minimum of one additional soil profile pit and two additional soil borings shall be conducted for each additional 2 acres. |
|
|
|
1 |
1 |
|
|
|
|
1 |
1 |
|
|
|
|
1 |
1 |
|
|
|
|
1 |
1 |
|
|
|
|
1 |
1 |
|
|
|
|
1 |
1 |
|
|
|
|
1 |
1 |
|
|
|
|
|
|
|
|
| Determining Depth of Soil Profile Pit/Boring |
|
|
|
|
|
| Test No. |
Existing Grade Elevation (ft) |
40 in. Below Existing Grade (ft) |
SHWT Elevation (ft) |
Depth of Test Pit/Boring from Existing Grade (ft) |
Notes |
| 1 |
11 |
7.66 |
- |
7.66 |
|
| 2 |
9 |
5.66 |
7.5 |
7.5 |
SHWT is within 24 inches. D soil |
| 3 |
9 |
5.66 |
6.5 |
5.66 |
|
| 4 |
|
|
|
|
|
| 5 |
|
|
|
|
|
| 6 |
|
|
|
|
|
| 7 |
|
|
|
|
|
| 8 |
|
|
|
|
|
| 9 |
|
|
|
|
|
| 10 |
|
|
|
|
|
Source context and notes
Figure 12-3: Example of an HSG Soil Testing Worksheet
HSG Soil Testing Worksheet
Project Name:
Location:
| Determination of Hydrologic Soil Group Worksheet | | | | | |
| --- | --- | --- | --- | --- | --- |
| Determining No. of Test Pit for HSG | | | | Requirements | |
| Unknown Mapping Unit No. | Size of Mapping Unit (acre) | # of Soil Profile Pit(s) Required | # of Soil Boring(s) Required | 1. a mapping unit of less than 0.5 acre, a minimum of one soil profile pit and one soil boring shall be conducted within that mapping unit.
2. a minimum of one soil profile pit and four soil borings shall be conducted within each soil mapping unit of 0.5 acre or more and less than or equal to 2 acres, as shown on the NRCS Web Soil Survey.
3. a mapping unit larger than 2 acres within the limits of the overall site, a minimum of one additional soil profile pit and two additional soil borings shall be conducted for each additional 2 acres. | |
| | | 1 | 1 | | |
| | | 1 | 1 | | |
| | | 1 | 1 | | |
| | | 1 | 1 | | |
| | | 1 | 1 | | |
| | | 1 | 1 | | |
| | | 1 | 1 | | |
| | | | | | |
| Determining Depth of Soil Profile Pit/Boring | | | | | |
| Test No. | Existing Grade Elevation (ft) | 40 in. Below Existing Grade (ft) | SHWT Elevation (ft) | Depth of Test Pit/Boring from Existing Grade (ft) | Notes |
| 1 | 11 | 7.66 | - | 7.66 | |
| 2 | 9 | 5.66 | 7.5 | 7.5 | SHWT is within 24 inches. D soil |
| 3 | 9 | 5.66 | 6.5 | 5.66 | |
| 4 | | | | | |
| 5 | | | | | |
| 6 | | | | | |
| 7 | | | | | |
| 8 | | | | | |
| 9 | | | | | |
| 10 | | | | | |
Soil profile pits and soil borings performed for the purpose of determining HSG must extend at least 40 inches below existing grade, except when the SHWT is at a depth of 24 inches or less, the exploration may be terminated before excavation to the depth of 40 inches below existing grade and the soils are classified as HSG D.
## Subsection 1d: Seasonal High Water Table (SHWT) Location
This subsection establishes the guidelines to be followed for determining the upper limit of the zone of saturation, which is known as the Seasonal High Water Table (SHWT). As mentioned earlier, the location of the SHWT can be very important to determining the HSGs present on a site. Additionally, most of the stormwater management BMPs presented in this manual must meet the minimum separation from the SHWT specified in the relevant subchapter. The location of the SHWT shall be determined by one of the following methods:
9. Table 12-5: SHWT Determination - Mottling Shows Redoximorphic Features within Soil Exploration
BMP 2024, Ch 12, p. 12
| Time Period |
Observation |
Conclusion |
| January-December |
Water table is observed above mottling showing redoximorphic features |
SHWT is at location of observed water table |
|
Water table is observed below mottling showing redoximorphic features or no water table is observed within the soil exploration depth |
SHWT is at location of mottling showing redoximorphic features |
Source context and notes
a. During the months of January through April, inclusive, water levels may be measured directly within soil profile pits or borings. Whenever the Department determines that there has been a significant departure from normal climatic conditions, the Department may, with due notice to the administrative authority, lengthen or shorten the period allowed for direct measurement during any given year. In low lying coastal areas where groundwater levels fluctuate with the tides, measurements shall be taken at the time of highest groundwater elevation in response to tidal fluctuation or
b. During other times of the year, the depth to the SHWT may be obtained from the NRCS Web Soil Survey provided that the soil series present at the site is identified based upon comparison of soil profile morphology observed within a soil profile pit and the soil profile description provided for the soil series in question within the NRCS Web Soil Survey. In cases where SHWT is shown as a range of elevations in the NRCS Web Soil Survey, the highest elevation of the range shall be used as the SHWT.
Below, and on the following page, are Tables 12-5 and 12-6 providing guidance on SHWT determination, depending on observations and the time of year. Table 12-5 corresponds with Item 1 within this subsection, and Table 12-6 corresponds with Item 2.
Table 12-5: SHWT Determination - Mottling Shows Redoximorphic Features within Soil Exploration
| Time Period | Observation | Conclusion |
| --- | --- | --- |
| January-December | Water table is observed above mottling showing redoximorphic features | SHWT is at location of observed water table |
| | Water table is observed below mottling showing redoximorphic features or no water table is observed within the soil exploration depth | SHWT is at location of mottling showing redoximorphic features |
10. Table 12-6: SHWT Determination - Mottling Shows No Redoximorphic Features within Soil Exploration
BMP 2024, Ch 12, p. 13
| Time Period |
Observation |
Conclusion |
| January-April |
Water table is observed |
SHWT is at location of the observed water table |
|
Water table is not observed |
SHWT is assumed to be at the lowest elevation of soil exploration |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Table 12-6: SHWT Determination - Mottling Shows No Redoximorphic Features within Soil Exploration
| Time Period | Observation | Conclusion |
| --- | --- | --- |
| January-April | Water table is observed | SHWT is at location of the observed water table |
| | Water table is not observed | SHWT is assumed to be at the lowest elevation of soil exploration |
| May-December | The soil profile observed in a profile pit is verified against the detailed information provided in the NRCS Web Soil Survey | The depth to water table given in NRCS Web Soil Survey may be used as the SHWT, provided that the Beginning Month and the Ending Month is between January and April in the Advanced Options for Depth to Water Table:
Note: If a range is provided for the water table elevation, the highest elevation of the range shall be used as the SHWT. |
| | The soil profile in a profile pit is not verified against the detailed information provided in the NRCS Web Soil Survey | The SHWT is undetermined. Soil test following Subsection 1d needs to be conducted in January through April or alternatively conducted during May through December at other locations in compliance with Section 2. |
## Subsection 1e: Perched Water Table Requirements
11. Table 12-6: SHWT Determination - Mottling Shows No Redoximorphic Features within Soil Exploration
BMP 2024, Ch 12, p. 13
| | The soil profile in a profile pit is not verified against the detailed information provided in the NRCS Web Soil Survey | The SHWT is undetermined. Soil test following Subsection 1d needs to be conducted in January through April or alternatively conducted during May through December at other locations in compliance with Section 2. |
Source context and notes
| Time Period | Observation | Conclusion |
| --- | --- | --- |
| January-April | Water table is observed | SHWT is at location of the observed water table |
| | Water table is not observed | SHWT is assumed to be at the lowest elevation of soil exploration |
| May-December | The soil profile observed in a profile pit is verified against the detailed information provided in the NRCS Web Soil Survey | The depth to water table given in NRCS Web Soil Survey may be used as the SHWT, provided that the Beginning Month and the Ending Month is between January and April in the Advanced Options for Depth to Water Table:
Note: If a range is provided for the water table elevation, the highest elevation of the range shall be used as the SHWT. |
| | The soil profile in a profile pit is not verified against the detailed information provided in the NRCS Web Soil Survey | The SHWT is undetermined. Soil test following Subsection 1d needs to be conducted in January through April or alternatively conducted during May through December at other locations in compliance with Section 2. |
## Subsection 1e: Perched Water Table Requirements
If a groundwater table is encountered during soil exploration, in accordance with N.J.A.C. 7:9-5.8 (e), it shall be considered to be perched if it is present immediately above a hydraulically restrictive horizon, such as clay or fragipan, underlain by a layer of permeable unsaturated soil which is free of mottling and has a chroma of four or higher. In cases where a perched water table exists at the location of a BMP, additional soil testing is required to determine the extent of the hydraulically restrictive horizon within the area of the BMP, which is sometimes referred to as the "footprint." The following requirements must be followed:
12. Table 12
BMP 2024, Ch 12, p. 15
| No. |
Testing Requirement Applicability |
Page No. |
| 1 |
Requirements for any infiltration BMP |
15 |
| 2 |
Requirements for a site with one or more infiltration BMPs, each equal to or less than five hundred square feet in area |
16 |
| 3 |
Requirements for a site with one or more small-scale green infrastructure BMPs that infiltrate runoff into subsoil, where each green infrastructure BMP is greater than 500 square feet in area, exclusive of porous paving systems |
16 |
| 4 |
Requirements for a linear BMP |
16 |
| 5 |
Allowable substitutions |
17 |
| 6 |
Proximity of soil exploration(s) to the actual location of a BMP |
17 |
| 7 |
When additional soil profile pit(s) may be required |
18 |
Source context and notes
underneath and surrounding the basin is sufficiently impermeable to prevent excessive seepage, such as standard constructed wetlands and wet ponds. Under such circumstances, the depth and location of the soil exploration may not be limited to the requirements under this subsection. The design engineer needs to conduct soil tests for the saturated soil hydraulic conductivity using their professional judgement and the engineering needs.
## Subsection 2a: Soil Testing Requirements for Infiltration BMPs
## Required Quantity and Placement of Soil Explorations
For infiltration BMPs, soil profile pits and soil borings must be conducted in the infiltration area, which is the area of the BMP providing infiltration. The infiltration area does not include the slope, side or wall areas of a BMP. The location and numbers of soil profile pits and soil borings must meet the requirements listed in Items 1 through 7 in the index below and covered on the subsequent pages. Example 3, found in Table 12-7 on Page 18 illustrates the various requirements.
| No. | Testing Requirement Applicability | Page No. |
| --- | --- | --- |
| 1 | Requirements for any infiltration BMP | 15 |
| 2 | Requirements for a site with one or more infiltration BMPs, each equal to or less than five hundred square feet in area | 16 |
| 3 | Requirements for a site with one or more small-scale green infrastructure BMPs that infiltrate runoff into subsoil, where each green infrastructure BMP is greater than 500 square feet in area, exclusive of porous paving systems | 16 |
| 4 | Requirements for a linear BMP | 16 |
| 5 | Allowable substitutions | 17 |
| 6 | Proximity of soil exploration(s) to the actual location of a BMP | 17 |
| 7 | When additional soil profile pit(s) may be required | 18 |
## 1. Requirements for any infiltration BMP:
- Except as specified in Items 2, 3 and 4 listed below, a minimum of two soil profile pits must be excavated within the infiltration area of any proposed infiltration BMP to determine the suitability and distribution of soil types and seasonal high water table present at location of the BMP.
- Placement of the test pits must be sufficient to provide adequate characterization of the infiltration area.
- For BMP infiltration areas larger than ten thousand square feet, a minimum of one additional soil profile pit shall be conducted for each additional area of ten thousand square feet.
- At least one test to establish the soil hydraulic conductivity must be conducted for each soil profile pit.
13. Table 12-7: Example 3 – Required Number of Soil Profile Pits and Soil Borings
BMP 2024, Ch 12, p. 18
| Type of Soil Exploration and Number Required: |
Example BMPs |
|
|
|
|
|
|
9,000 sf Infiltration Basin |
25,450 sf Infiltration Basin |
35,000 sf Porous Paving System |
10 Rain Gardens Each = 400 sf |
4 Small-Scale Infiltration Basins, Each = 1,500 sf |
2,500 ft Linear Bioretention Swale |
| Soil Profile Pit(s) |
2 |
4 Total: 2 (1st 10,000 sf) + 1 (2nd 10,000 sf) + 1 (add'l. 5,450 sf) |
5 Total: 2 (1st 10,000 sf) + 1 (2nd 10,000 sf) + 1 (3rd 10,000 sf) + 1 (add'l. 5,000 sf) |
1 |
1 |
2 Total: 1 (1st 500 ft) + 1 (2,000 ft) |
| Soil Boring(s) |
None Required |
None Required |
None Required |
10 Total: 1 per each GI BMP |
8 |
3 Total: 1 per each 500 ft of length after the first 500 feet |
Source context and notes
7. When additional soil profile pit(s) may be required
- Where soil and/or groundwater properties vary significantly between soil explorations, additional soil profile pits shall be conducted as necessary to resolve such differences and accurately characterize the subsurface conditions below the infiltration BMP.
- See Example 3, in Table 12-7 below, to determine the number of soil profile pits and soil borings necessary for a variety of stormwater infiltration BMPs of many sizes.
Table 12-7: Example 3 – Required Number of Soil Profile Pits and Soil Borings
| Type of Soil Exploration and Number Required: | Example BMPs | | | | | |
| --- | --- | --- | --- | --- | --- | --- |
| | 9,000 sf Infiltration Basin | 25,450 sf Infiltration Basin | 35,000 sf Porous Paving System | 10 Rain Gardens Each = 400 sf | 4 Small-Scale Infiltration Basins, Each = 1,500 sf | 2,500 ft Linear Bioretention Swale |
| Soil Profile Pit(s) | 2 | 4 Total: 2 (1st 10,000 sf) + 1 (2nd 10,000 sf) + 1 (add'l. 5,450 sf) | 5 Total: 2 (1st 10,000 sf) + 1 (2nd 10,000 sf) + 1 (3rd 10,000 sf) + 1 (add'l. 5,000 sf) | 1 | 1 | 2 Total: 1 (1st 500 ft) + 1 (2,000 ft) |
| Soil Boring(s) | None Required | None Required | None Required | 10 Total: 1 per each GI BMP | 8 | 3 Total: 1 per each 500 ft of length after the first 500 feet |
14. Table 12-8: Example 5 – Required Depth for Locating the Most Hydraulically Restrictive Layer
BMP 2024, Ch 12, p. 20
| Criteria |
Example BMPs |
|
|
|
|
|
Bioretention Basin |
Infiltration Basin |
|
|
|
|
|
w/ 6 in Sand Layer |
w/ 6 in Sand Layer |
w/ 5 ft Sand Replacement Below Basin Bottom* |
w/ 10 ft Sand Replacement Below Basin Bottom* |
| Maximum Standing Water Depth (ft) |
1 |
2 |
2 |
2 |
2 |
| SHWT (ft) Below the Basin Bottom |
12 |
12 |
4** |
12 |
18 |
| Depth range to locate the most hydraulically restrictive layer(s) |
0 to 8 ft below the bottom of the basin |
0 to 8 ft below the bottom of the sand layer |
0 to 4 ft below the bottom of the sand layer |
5 to 12 ft below the bottom of the basin |
10 to 18 ft below the bottom of the basin |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Table 12-8: Example 5 – Required Depth for Locating the Most Hydraulically Restrictive Layer
| Criteria | Example BMPs | | | | |
| --- | --- | --- | --- | --- | --- |
| | Bioretention Basin | Infiltration Basin | | | |
| | | w/ 6 in Sand Layer | w/ 6 in Sand Layer | w/ 5 ft Sand Replacement Below Basin Bottom* | w/ 10 ft Sand Replacement Below Basin Bottom* |
| Maximum Standing Water Depth (ft) | 1 | 2 | 2 | 2 | 2 |
| SHWT (ft) Below the Basin Bottom | 12 | 12 | 4** | 12 | 18 |
| Depth range to locate the most hydraulically restrictive layer(s) | 0 to 8 ft below the bottom of the basin | 0 to 8 ft below the bottom of the sand layer | 0 to 4 ft below the bottom of the sand layer | 5 to 12 ft below the bottom of the basin | 10 to 18 ft below the bottom of the basin |
*The depth of sand replacement specified does not include the required 0.5 ft deep sand layer comprising the surface of the basin infiltration area.
**The location of the SHWT is the limiting factor in this case
On the following page is an example of an Excel spreadsheet that may be used to calculate the number of soil profile pits and borings, plus the depth(s), required for an infiltration BMP as part of soil hydraulic conductivity testing. The workbook including this spreadsheet may be downloaded from the Department website, under the heading for Chapter 12 of the BMP Manual, at:
https://dep.nj.gov/stormwater/bmp-manual/
15. Table 15
BMP 2024, Ch 12, p. 21
| No. of Soil Explorations Required for Stormwater BMPs (Single, Non-GI, Large BMP, Linear BMP) |
|
|
|
|
| Type (select one) |
Size of Infiltration Area (square feet) |
Length of Linear BMP (ft) |
# of Soil Profile Pits Required |
# of Soil Borings Required |
| Single BMP |
6,500 |
-- |
2 |
0 |
| Single BMP |
25,600 |
-- |
4 |
0 |
| Linear BMP |
-- |
450 |
1 |
0 |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
|
|
|
|
|
| No. of Soil Explorations Required for Stormwater BMPs in accordance with Items 2 and 3 of Subsection 2a in Ch. 12 |
|
|
|
|
| Type (select one) |
# of Soil Mapping Unit |
# of BMPs |
# of Soil Profile Pits Required |
# of Soil Borings Required |
| Small BMPs <= 500 sf |
1 |
5 |
1 |
5 |
| GI BMPs > 500 sf |
2 |
9 |
2 |
18 |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
|
-- |
-- |
-- |
-- |
Source context and notes
Figure 12-5a: Example of a Hydraulic Conductivity Testing Worksheet for Infiltration BMPs
Soil Explorations for Stormwater BMPs
Project Name:
Location:
| No. of Soil Explorations Required for Stormwater BMPs (Single, Non-GI, Large BMP, Linear BMP) | | | | |
| --- | --- | --- | --- | --- |
| Type (select one) | Size of Infiltration Area (square feet) | Length of Linear BMP (ft) | # of Soil Profile Pits Required | # of Soil Borings Required |
| Single BMP | 6,500 | -- | 2 | 0 |
| Single BMP | 25,600 | -- | 4 | 0 |
| Linear BMP | -- | 450 | 1 | 0 |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
| | | | | |
| No. of Soil Explorations Required for Stormwater BMPs in accordance with Items 2 and 3 of Subsection 2a in Ch. 12 | | | | |
| Type (select one) | # of Soil Mapping Unit | # of BMPs | # of Soil Profile Pits Required | # of Soil Borings Required |
| Small BMPs <= 500 sf | 1 | 5 | 1 | 5 |
| GI BMPs > 500 sf | 2 | 9 | 2 | 18 |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
| | -- | -- | -- | -- |
On the following page is depicted the portion of example Excel spreadsheet for determining the depth of the soil profile pit/boring.
16. Table 16
BMP 2024, Ch 12, p. 22
| Determining Depth of Soil Profile Pit/Boring |
|
|
|
|
|
| Test Pit / Boring No. |
Existing Grade EL (ft) |
Lowest Bottom EL (ft) |
Maximum Potential Water Depth (ft) |
Depth of Test Pit/Boring Depth from Existing Grade (in) |
Elevation of Excavation EL (ft) |
| 1 |
100 |
96 |
2 |
144 |
88 |
| 2 |
|
|
|
96 |
-8 |
| 3 |
|
|
|
96 |
-8 |
| 4 |
|
|
|
96 |
-8 |
| 5 |
|
|
|
96 |
-8 |
| 6 |
|
|
|
96 |
-8 |
| 7 |
|
|
|
96 |
-8 |
| 8 |
|
|
|
96 |
-8 |
| 9 |
|
|
|
96 |
-8 |
| 10 |
|
|
|
96 |
-8 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Figure 12-5b: Hydraulic Conductivity Test Worksheet for Infiltration BMPs – Determining the Depth of Soil Profit Pit/Boring
| Determining Depth of Soil Profile Pit/Boring | | | | | |
| --- | --- | --- | --- | --- | --- |
| Test Pit / Boring No. | Existing Grade EL (ft) | Lowest Bottom EL (ft) | Maximum Potential Water Depth (ft) | Depth of Test Pit/Boring Depth from Existing Grade (in) | Elevation of Excavation EL (ft) |
| 1 | 100 | 96 | 2 | 144 | 88 |
| 2 | | | | 96 | -8 |
| 3 | | | | 96 | -8 |
| 4 | | | | 96 | -8 |
| 5 | | | | 96 | -8 |
| 6 | | | | 96 | -8 |
| 7 | | | | 96 | -8 |
| 8 | | | | 96 | -8 |
| 9 | | | | 96 | -8 |
| 10 | | | | 96 | -8 |
Note: Soil profile pits and soil borings performed for the purpose of designing a stormwater BMP must extend to either a minimum depth of eight feet below the lowest elevation of the basin bottom or to a depth that is at least twice the maximum potential water depth generated by the largest design storm, whichever is greater.
## Subsection 2b: Soil Testing for Non-Infiltration BMPs with a Required Separation from the SHWT
The location and depth of soil exploration in Subsection 2a may be followed with these clarifications:
17. Table 17
BMP 2024, Ch 12, p. 25
| DISIGNED BY: |
|
NAME |
| NJPE No. |
SE CODE |
|
| DATE |
JUNE 18, 2012 |
|
| LAST REV. |
N/A |
|
Source context and notes
= ELEV. 128.0 OR
b. TWO TIMES THE MAXIMUM DEPTH OF
WATER CH4 IN THE BMP (AS DEFINED
OF THE LOWEST SPELLWAY INVERT
ELEV.) = ELEV.128.0.
THEREFORE THE TEST PITS MUST
PENETRATE TO MIN. ELEV. 128.0
| DISIGNED BY: | | NAME |
| --- | --- | --- |
| NJPE No. | SE CODE | |
| DATE | JUNE 18, 2012 | |
| LAST REV. | N/A | |
18. Table 18
BMP 2024, Ch 12, p. 26
| Soil Profile Report |
|
|
|
|
|
| Project Name: |
|
|
Municipality: |
|
|
| Project Location: |
|
|
Block/Lot Info: |
|
|
| Date of Observation of SHWT: |
|
|
Lowest Point in BMP (ft) = |
|
5 |
| Prepared by: |
|
|
Max Water Depth (ft) = |
|
2 |
|
|
|
Required Soil Profile Pit Depth (ft) = 13 |
|
|
| Test Pit No.: |
|
|
Locating the Seasonal High Water Table, if determined by direct observation, must be performed between January 1 and April 30. If determined by the soil morphological observation, redoximorphic features must be noted. |
|
|
| Observation Reported: |
|
Elevation (ft) |
|
|
|
| Ground Level: |
|
100 |
|
|
|
| Seasonal High Water Table: |
|
|
Generally, most USDA Soil textual types listed below are arranged from most to least hydraulically restrictive; if unsure of the soil type present, multiple soil layers may need to be tested. Clay, Clay Loam, Loam, Silty Clay, Silty Clay Loam, Silt Loam, Silt, Sandy Clay, Sandy Clay Loam, Loamy Sand, Sandy Loam, Sand. |
|
|
| Pit bottom: |
|
87 |
|
|
|
| USDA Soil Texture (select one) |
Check box if most hydraulically restrictive |
Top Elevation / Bottom Elevation (ft) |
Direct Observation of Water Table (ft), if any |
Soil Morphological Observation |
Notes |
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
|
☐ |
/ |
|
|
|
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Figure 12-8: Soil Profile Report Template
| Soil Profile Report | | | | | |
| --- | --- | --- | --- | --- | --- |
| Project Name: | | | Municipality: | | |
| Project Location: | | | Block/Lot Info: | | |
| Date of Observation of SHWT: | | | Lowest Point in BMP (ft) = | | 5 |
| Prepared by: | | | Max Water Depth (ft) = | | 2 |
| | | | Required Soil Profile Pit Depth (ft) = 13 | | |
| Test Pit No.: | | | Locating the Seasonal High Water Table, if determined by direct observation, must be performed between January 1 and April 30. If determined by the soil morphological observation, redoximorphic features must be noted. | | |
| Observation Reported: | | Elevation (ft) | | | |
| Ground Level: | | 100 | | | |
| Seasonal High Water Table: | | | Generally, most USDA Soil textual types listed below are arranged from most to least hydraulically restrictive; if unsure of the soil type present, multiple soil layers may need to be tested. Clay, Clay Loam, Loam, Silty Clay, Silty Clay Loam, Silt Loam, Silt, Sandy Clay, Sandy Clay Loam, Loamy Sand, Sandy Loam, Sand. | | |
| Pit bottom: | | 87 | | | |
| USDA Soil Texture (select one) | Check box if most hydraulically restrictive | Top Elevation / Bottom Elevation (ft) | Direct Observation of Water Table (ft), if any | Soil Morphological Observation | Notes |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
| | ☐ | / | | | |
19. Table 19
BMP 2024, Ch 12, p. 31
| Subsection No. |
Test Name |
Page No. |
| A1 |
Percolation Test |
32 |
| A2 |
Tube Permeameter Test |
37 |
| A3 |
Basin Flooding Test |
44 |
| A4 |
Modified Basin Flooding Test |
45 |
| A5 |
Single Ring Infiltration Test |
47 |
Source context and notes
This addendum provides the Department summary of the NRCS guidance documents to establish hydrologic soil group based on hydraulic conductivity and the procedures for a percolation test, a tube permeameter test and a basin flooding test, which was mentioned in Section 3b above.
## Part A: Procedures for Soil Hydraulic Conductivity Testing
Test procedures for each of the testing methods cited in Section 3 above are found beginning on the pages specified below.
Hydraulic Conductivity Test Procedures
| Subsection No. | Test Name | Page No. |
| --- | --- | --- |
| A1 | Percolation Test | 32 |
| A2 | Tube Permeameter Test | 37 |
| A3 | Basin Flooding Test | 44 |
| A4 | Modified Basin Flooding Test | 45 |
| A5 | Single Ring Infiltration Test | 47 |
20. Table 12-9: $a$ Values for Corresponding Test Hole Diameters
BMP 2024, Ch 12, p. 35
| Parameter |
Values |
|
|
|
|
|
| d (in) |
6 |
8 |
9 |
10 |
11 |
12 |
| a |
20.00 |
24.00 |
25.71 |
27.27 |
28.70 |
30.00 |
Source context and notes
$$
K _ {s} = \frac {a}{P _ {m}}
$$
where, $a$ represents the right half of Equation 2. Thus, for various values of $d$ , $a$ is calculated as shown in Table 12-9 below:
Table 12-9: $a$ Values for Corresponding Test Hole Diameters
| Parameter | Values | | | | | |
| --- | --- | --- | --- | --- | --- | --- |
| d (in) | 6 | 8 | 9 | 10 | 11 | 12 |
| a | 20.00 | 24.00 | 25.71 | 27.27 | 28.70 | 30.00 |
b. If the test is performed in a rectangular or square hole, Equation 2 is modified as follows:
$$
P _ {m} = \frac {\Delta t}{6} \quad (Equation 1)
$$
$$
K _ {S} = \frac {1}{P _ {m}} \times \frac {6 0 A}{[ A + 6 (L + W) ]} \quad (Equation 2 modified)
$$
21. Table 21
BMP 2024, Ch 12, p. 36
| Percolation Test Data Sheet |
|
|
|
|
|
|
|
|
| Project: |
|
|
|
Date: |
|
|
|
|
| Municipality: |
|
|
|
|
|
|
|
|
| Test Hole Dimensions |
|
|
|
|
|
|
|
|
| Test Pit # |
|
|
|
|
|
|
|
|
| Test Hole Shape (select one) |
Round |
Enter the Diameter (in) if Round was selected |
6 |
Enter Dimensions (in) if Square or Rectangular was selected |
|
Length |
|
|
|
|
|
|
|
|
|
Width |
|
| Test Results |
|
|
|
|
|
|
|
|
| Trial No. |
Start Time at 6 inches |
Stop Time at 0 inch |
Time Interval (min) |
Initial Water Depth (in) |
Final Water Depth (in) |
Change in Water Level (in) |
Percolation Rate (min/in) |
Converted Hydraulic Conductivity (in/hr) |
| 1 |
0 |
25 |
25 |
6 |
0 |
6 |
4.167 |
4.800 |
| 2 |
0 |
24 |
24 |
6 |
0 |
6 |
4.000 |
5.000 |
| 3 |
|
|
0 |
6 |
0 |
6 |
|
|
| 4 |
|
|
0 |
6 |
0 |
6 |
|
|
| 5 |
|
|
0 |
6 |
0 |
6 |
|
|
|
|
|
|
|
|
Average |
|
4.900 |
| Test Hole Dimensions |
|
|
|
|
|
|
|
|
| Test Pit # |
|
|
|
|
|
|
|
|
| Test Hole Shape (select one) |
Sq/Rect |
Enter the Diameter (in) if Round was selected |
|
Enter Dimensions (in) if Square or Rectangular was selected |
|
Length |
10 |
|
|
|
|
|
|
|
|
Width |
10 |
| Test Results |
|
|
|
|
|
|
|
|
| Trial No. |
Start Time at 6 inches |
Stop Time at 0 inch |
Time Interval (min) |
Initial Water Depth (in) |
Final Water Depth (in) |
Change in Water Level (in) |
Percolation Rate (min/in) |
Converted Hydraulic Conductivity (in/hr) |
| 1 |
0 |
16 |
16 |
6 |
0 |
6 |
2.667 |
10.227 |
| 2 |
|
|
0 |
6 |
0 |
6 |
|
|
| 3 |
|
|
0 |
6 |
0 |
6 |
|
|
| 4 |
|
|
0 |
6 |
0 |
6 |
|
|
| 5 |
|
|
0 |
6 |
0 |
6 |
|
|
|
|
|
|
|
|
Average |
|
10.227 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Figure 12-10: Percolation Test Data Sheet
| Percolation Test Data Sheet | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Project: | | | | Date: | | | | |
| Municipality: | | | | | | | | |
| Test Hole Dimensions | | | | | | | | |
| Test Pit # | | | | | | | | |
| Test Hole Shape (select one) | Round | Enter the Diameter (in) if Round was selected | 6 | Enter Dimensions (in) if Square or Rectangular was selected | | Length | | |
| | | | | | | | Width | |
| Test Results | | | | | | | | |
| Trial No. | Start Time at 6 inches | Stop Time at 0 inch | Time Interval (min) | Initial Water Depth (in) | Final Water Depth (in) | Change in Water Level (in) | Percolation Rate (min/in) | Converted Hydraulic Conductivity (in/hr) |
| 1 | 0 | 25 | 25 | 6 | 0 | 6 | 4.167 | 4.800 |
| 2 | 0 | 24 | 24 | 6 | 0 | 6 | 4.000 | 5.000 |
| 3 | | | 0 | 6 | 0 | 6 | | |
| 4 | | | 0 | 6 | 0 | 6 | | |
| 5 | | | 0 | 6 | 0 | 6 | | |
| | | | | | | Average | | 4.900 |
| Test Hole Dimensions | | | | | | | | |
| Test Pit # | | | | | | | | |
| Test Hole Shape (select one) | Sq/Rect | Enter the Diameter (in) if Round was selected | | Enter Dimensions (in) if Square or Rectangular was selected | | Length | 10 | |
| | | | | | | | Width | 10 |
| Test Results | | | | | | | | |
| Trial No. | Start Time at 6 inches | Stop Time at 0 inch | Time Interval (min) | Initial Water Depth (in) | Final Water Depth (in) | Change in Water Level (in) | Percolation Rate (min/in) | Converted Hydraulic Conductivity (in/hr) |
| 1 | 0 | 16 | 16 | 6 | 0 | 6 | 2.667 | 10.227 |
| 2 | | | 0 | 6 | 0 | 6 | | |
| 3 | | | 0 | 6 | 0 | 6 | | |
| 4 | | | 0 | 6 | 0 | 6 | | |
| 5 | | | 0 | 6 | 0 | 6 | | |
| | | | | | | Average | | 10.227 |
22. Table 12-10: Soil Hydraulic Conductivity Classes
BMP 2024, Ch 12, p. 42
| Measured Hydraulic Conductivity (in/hr) |
Soil Hydraulic Conductivity Class |
| Greater than or equal to 20 |
K5 |
| 6 – 20 |
K4 |
| 2 – 6 |
K3 |
| 0.6 – 2 |
K2 |
| 0.2 – 0.6 |
K1 |
| Less than 0.2 |
K0 |
Source context and notes
# Soil Testing Criteria
Source revision: March 2024.
Table 12-10: Soil Hydraulic Conductivity Classes
| Measured Hydraulic Conductivity (in/hr) | Soil Hydraulic Conductivity Class |
| --- | --- |
| Greater than or equal to 20 | K5 |
| 6 – 20 | K4 |
| 2 – 6 | K3 |
| 0.6 – 2 | K2 |
| 0.2 – 0.6 | K1 |
| Less than 0.2 | K0 |
ii. Where the results of replicate tests differ by more than one soil hydraulic conductivity class, the samples must be examined for the defects listed below. If any of these defects are found, the defective core(s) must be discarded and the test repeated using a new replicate sample for each defective replicate sample.
- Cracks, worm channels, large root channels or poor soil tube contact within the sample yielding the highest soil hydraulic conductivity value(s),
- Large pieces of gravel, roots or unsaturated soil within the interior of the sample yielding the slowest soil hydraulic conductivity value(s) and
- Smearing or compaction of the upper or lower surface of the sample yielding the lowest soil hydraulic conductivity value(s).
c. Step Three: When test results have been obtained with an acceptable range of variability as defined in "Step Two" above, the results shall be interpreted as follows:
Images on table pages
Page associations do not establish that a crop depicts a specific table.