TEXAS OSSF Installer 1 Test Preparation
Comprehensive Resource To Help You Ace
2026-2027 Includes Frequently Tested
Questions With ELABORATED 100% Correct
COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!!
Current Update!!
1. Spots and streaks in soil coloration are called:
A. Horizons
B. Stains
C. Mottles Correct Answer
D. Veins
2. Soil mottles are an indication of:
A. Excess organic matter
B. Seasonal saturation Correct Answer
C. High permeability
D. Clay texture
3. Soil showing signs of seasonal saturation within what depth below the bottom
of a proposed drain field is considered unsuitable?
A. 12 inches
B. 18 inches
C. 24 inches Correct Answer
D. 36 inches
,4. When conducting a site evaluation, soil borings or pits must be excavated to at
least how many inches below the bottom of the proposed drain field?
A. 12 inches
B. 18 inches
C. 24 inches Correct Answer
D. 48 inches
5. Inadequate lot size is the most commonly identified reason for OSSF failure.
A. True Correct Answer
B. False
6. The total area available for an OSSF must be how much larger than the design
area of the initial system?
A. 1.5 times
B. 2 times Correct Answer
C. 2.5 times
D. 3 times
7. What is the minimum and maximum slope considered suitable for an OSSF site?
A. 0% to 15%
B. 1% to 20%
C. 2% to 30% Correct Answer
D. 5% to 40%
8. A septic tank must be set back at least how many feet from a public well?
,A. 25 ft
B. 40 ft
C. 50 ft Correct Answer
D. 100 ft
9. A septic tank must be set back at least 50 feet from which of the following?
A. Public wells only
B. Private wells only
C. Pressure cemented wells only
D. All three types of wells Correct Answer
10. Septic tanks and drainfields must be set back how many feet from homes,
swimming pools, and property lines?
A. 3 ft
B. 5 ft Correct Answer
C. 10 ft
D. 20 ft
11. Septic tanks and drainfields must be set back how many feet from private
water lines?
A. 5 ft
B. 10 ft Correct Answer
C. 15 ft
D. 20 ft
12. Drainfields must be set back how many feet from bodies of water?
, A. 25 ft
B. 50 ft
C. 75 ft Correct Answer
D. 100 ft
13. Septic tanks must be set back how many feet from bodies of water?
A. 25 ft
B. 40 ft
C. 50 ft Correct Answer
D. 75 ft
14. The minimum lot size for a septic system served by an individual well is:
A. ½ acre
B. ¾ acre
C. 1 acre Correct Answer
D. 2 acres
15. The minimum lot size for a septic system served by a public water supply is:
A. ¼ acre
B. ½ acre Correct Answer
C. 1 acre
D. 2 acres
16. System capacity must be:
A. Less than system load
B. Equal to system load
Comprehensive Resource To Help You Ace
2026-2027 Includes Frequently Tested
Questions With ELABORATED 100% Correct
COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!!
Current Update!!
1. Spots and streaks in soil coloration are called:
A. Horizons
B. Stains
C. Mottles Correct Answer
D. Veins
2. Soil mottles are an indication of:
A. Excess organic matter
B. Seasonal saturation Correct Answer
C. High permeability
D. Clay texture
3. Soil showing signs of seasonal saturation within what depth below the bottom
of a proposed drain field is considered unsuitable?
A. 12 inches
B. 18 inches
C. 24 inches Correct Answer
D. 36 inches
,4. When conducting a site evaluation, soil borings or pits must be excavated to at
least how many inches below the bottom of the proposed drain field?
A. 12 inches
B. 18 inches
C. 24 inches Correct Answer
D. 48 inches
5. Inadequate lot size is the most commonly identified reason for OSSF failure.
A. True Correct Answer
B. False
6. The total area available for an OSSF must be how much larger than the design
area of the initial system?
A. 1.5 times
B. 2 times Correct Answer
C. 2.5 times
D. 3 times
7. What is the minimum and maximum slope considered suitable for an OSSF site?
A. 0% to 15%
B. 1% to 20%
C. 2% to 30% Correct Answer
D. 5% to 40%
8. A septic tank must be set back at least how many feet from a public well?
,A. 25 ft
B. 40 ft
C. 50 ft Correct Answer
D. 100 ft
9. A septic tank must be set back at least 50 feet from which of the following?
A. Public wells only
B. Private wells only
C. Pressure cemented wells only
D. All three types of wells Correct Answer
10. Septic tanks and drainfields must be set back how many feet from homes,
swimming pools, and property lines?
A. 3 ft
B. 5 ft Correct Answer
C. 10 ft
D. 20 ft
11. Septic tanks and drainfields must be set back how many feet from private
water lines?
A. 5 ft
B. 10 ft Correct Answer
C. 15 ft
D. 20 ft
12. Drainfields must be set back how many feet from bodies of water?
, A. 25 ft
B. 50 ft
C. 75 ft Correct Answer
D. 100 ft
13. Septic tanks must be set back how many feet from bodies of water?
A. 25 ft
B. 40 ft
C. 50 ft Correct Answer
D. 75 ft
14. The minimum lot size for a septic system served by an individual well is:
A. ½ acre
B. ¾ acre
C. 1 acre Correct Answer
D. 2 acres
15. The minimum lot size for a septic system served by a public water supply is:
A. ¼ acre
B. ½ acre Correct Answer
C. 1 acre
D. 2 acres
16. System capacity must be:
A. Less than system load
B. Equal to system load
