TITLE 77: PUBLIC HEALTH
CHAPTER I: DEPARTMENT OF PUBLIC HEALTH
SUBCHAPTER r: WATER AND SEWAGE
PART 905 PRIVATE SEWAGE DISPOSAL CODE
SECTION 905.APPENDIX A ILLUSTRATIONS AND EXHIBITS

Section 905.APPENDIX A   Illustrations and Exhibits

 

Section 905.ILLUSTRATION M   Soil Suitability for On-Site Sewage Design

 

Section 905.EXHIBIT A   Loading Rates in Square Feet Per Bedroom and Gallons/Square Feet/Day

 

Design

Group

Soil Group

(Most limiting

Layer)

Minimum

Separation

To Limiting

Layer (1)

Permeability

Range

Size of System

Residential

Reg. Absorption

(ft2/bedroom)

Institutional/Commercial

Allowable Application

Rate (GPD/ft2

 

 

 

 

 

 

 

I

1A

N/A

Very Rapid

N/A

N/A

II

2A; 2B; 2K

3 feet

Rapid

200

1.0

III

3B; 3K

3 feet

High

 

 

 

 

 

Moderately

220

0.91

 

 

 

Rapid

 

 

IV

3A; 3C; 3L;

3 feet

Low

 

 

 

4B; 4K

 

Moderately

240

0.84

 

 

 

Rapid

 

 

V

4A; 4C; 4D;

3 feet

Very High

 

 

 

4L; 4M; 5B;

 

Moderate

265

0.75

 

5D

 

 

 

 

VI

5C; 5E; 5K; 6F

3 feet

High

 

 

 

 

 

Moderate

290

0.69

VII

5A; 5H; 6D

2 feet

Moderate

325

0.62

VIII

4N; 5I; 5L

2 feet

Low

 

 

 

6A; 6E; 6G;

 

Moderate

385

0.52

 

6K

 

 

 

 

IX(2)

5J; 5M; 6C;

2 feet

High

 

 

 

6H; 6L; 7A;

 

Moderately

445

0.45

 

7D; 7F

 

Slow

 

 

X(2)

6I; 7E; 7G; 8A

2 feet

Low

 

 

 

 

 

Moderately

500

0.40

 

 

 

Slow

 

 

XI(2)

5N; 6J; 6M;

2 feet

Slow

740

0.27

 

7I; 7K

 

 

 

 

XII(2)

7J; 7L; 8I

2 feet

Very Slow

1000

0.20

XII(2)

6N; 7M; 7N;

N/A

N/A

N/A

0.00

 

8J; 8N

 

 

 

 

XIII

9

SUBSURFACE DISPOSAL NOT RECOMMENDED

 

NOTES:

 

(1)   Limiting layers include fragipans; bedrock; compact glacial tills; seasonal high water table or other soil profile features that will materially affect the absorption of liquid from the disposal field.

 

(2)   Soils in this group are less than the minimum percolation rate established in Section 905.Illustration H of this Part as suitable for subsurface seepage systems.

 

(Source: Section repealed, new Section added at 20 Ill. Reg. 2431, effective March 15, 1996)

Section 905.APPENDIX A   Illustrations and Exhibits

 

Section 905.EXHIBIT B   Key for Determining Sewage Loading Rates (Gallons/Square Feet/Day)

 

Section 905.EXHIBIT B   Key for Determining Sewage Loading Rates (Gallons/Square Feet/Day)

 

Structure and

Parent Material

Single grain; Granular;

Angular and Subangular Blocky; Prismatic

 

 

Structureless or Massive

Loess: Outwash

Till; Lacustrine

Platy 2

Week

Moderate

Strong

Moderate; Strong

Loess; Outwash

Till3; Lacustrine

Moist Consistence

lo vfr fr

lo vfr

fr fi

fr

fi

fr

fi

fr

fi

vfi

vfr

fr

vfr fr

fi vfi

Texture

A

B

C

D

E

F

G

H

I

J

K

L

M

N

1.

Fragmental;  Ext. or Very gravelly sand; Gravelly sand; Coarse sand; Gravelly loamy sand

> 1.004

N/A5

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

2.

Medium sand; Sand; Loamy course sand; Loamy sand;  Coarse sandy loam

1.00

1.00

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

1.00

N/A

N/A

N/A

3.

Fine sand; Loamy fine sand

0.84

0.91

0.84

N/A

N/A

N/A

N/A

N/A

N/A

N/A

0.91

0.84

N/A

N/A

4.

Sandy loam; Fine sandy loam; Gravelly sandy loam; Gravelly loam; Gravelly silt loam

0.75

0.84

0.75

0.75

N/A

N/A

N/A

N/A

N/A

N/A

0.84

0.75

0.75

0.52

5.

Loam; Silt loam; Very fine sandy loam; Sandy clay loam; Silt; Very fine sand; Loamy very fine sand

0.62

0.75

0.69

0.75

0.69

N/A

N/A

0.62

0.52

0.456

0.69

0.52

0.456

0.276

6.

Silty clay loam (<35% c); Clay loam (< 35% c)

.052

N/A

0.456

0.62

0.52

0.69

0.52

0.456

0.406

0.276

0.52

0.456

0.276

0.006

7.

Silty clay loam (>35% c); Clay loam (>35% c); Sandy clay (<40% c)

0.456

N/A

N/A

0.456

0.406

0.456

0.406

N/A

0.276

0.2 06

0.276

0.206

0.006

0.006

8.

Sandy clay (>40% c) Silty clay

0.406

N/A

N/A

N/A

N/A

N/A

N/A

N/A

0.206

0.006

N/A

N/A

N/A

0.0 6

9.

Clay; Organics; Fragic; Fragipan; Lithic; Paralithic

–––SOIL PROPERTIES HAVE VERY SERVERE LIMITATIONS; SUBSURFACE DISPOSAL NOT RECOMMENDED–––––

 

FOOTNOTES:

 

1      Disturbed soils are highly variable and require special on-site investigations.

2      Moderate or strong platy structure for the soil textures in Group 5 have a loading rate of 0.40 g/d/ft.  Platy structure having firm or very firm consistency and/or caused by mechanical compaction has a loading rate of 0.0 g/d/sq. ft.

3      Weakly structured BC horizons and basal glacial tills structured by geogenic processes have the same loading rates as structureless glacial till.

4      This soil group is estimated to have very rapid permeability and exceeds the maximum established rate in Section 905.Illustration H, Exhibit A of this Part.

5      N/A means not applicable.

6      These soil groups are estimated to have moderately slow to very slow permeability and are less than the minimum established rate in Section 905.Illustration H, Exhibit A of this Part.

 

(Source:  Section repealed, new Section added at 20 Ill. Reg. 2431, effective March 15, 1996)