Class D Water Operator License Exam TCEQ
Newest 2026 Questions and Correct Detailed
Answers Already Graded A+
T/F: If you do not fill out the submission form completely, you risk losing credit for
the sample. - CORRECT ANSWER-True (Submission form completion is
important)
T/F: The presence of fecal coliform in a water sample indicates fecal
contamination from a human or warm-blooded animal. - CORRECT ANSWER-
True (Sign of fecal contamination)
The purpose of the sample site plan is to assure bacteriological samples are
collected from active service connections which are representative of the
distribution system. - CORRECT ANSWER-Importance of sample site plan
True/False: Keeping the sample in ice or in a cooler prior to and during lab
transport is important because heat stimulates bacterial growth. - CORRECT
ANSWER-True
,What is the action level for lead and copper in mg/L? - CORRECT ANSWER-
Lead: 0.015 mg/L, Copper: 1.3 mg/L
True/False: Low doses of heavy metals like lead and copper can cause damage to
the central nervous system over time. - CORRECT ANSWER-True
What group of bacteria is used to indicate the possible presence of a pathogen? -
CORRECT ANSWER-Coliform
What is the term for the destruction of disease-causing microorganisms? -
CORRECT ANSWER-Pathogens
At room temperature, what form is chlorine in and how does its weight compare
to air? - CORRECT ANSWER-Chlorine is a greenish-yellow gas that is 2.5 times
heavier than air.
What must be kept in stock for disinfecting new water lines as required by the
State? - CORRECT ANSWER-Calcium hypochlorite
True/False: Hypochlorinators consist of a mixing tank and chemical solution feed
pump. - CORRECT ANSWER-True
, When chlorine gas is used, what type of breathing apparatus must be readily
accessible outside the chlorinator room? - CORRECT ANSWER-A full-face self-
contained breathing apparatus (SCBA) or supplied air respirator that meets OSHA
standards
True/False: Is it mandatory for all public water systems to have chlorination
facilities? - CORRECT ANSWER-True
True or False: In Texas, approximately 75% of all water is used for commercial,
industrial, or agricultural purposes. - CORRECT ANSWER-True
What percentage of Earth's surface is covered by water? - CORRECT ANSWER-
71%
Define drought: An extended period when a region experiences a deficiency in its
water supply, which can be atmospheric, ground, or surface water. - CORRECT
ANSWER-
True or False: Only about 1 gallon of tap water per person per day is used for
drinking and cooking. - CORRECT ANSWER-True
Newest 2026 Questions and Correct Detailed
Answers Already Graded A+
T/F: If you do not fill out the submission form completely, you risk losing credit for
the sample. - CORRECT ANSWER-True (Submission form completion is
important)
T/F: The presence of fecal coliform in a water sample indicates fecal
contamination from a human or warm-blooded animal. - CORRECT ANSWER-
True (Sign of fecal contamination)
The purpose of the sample site plan is to assure bacteriological samples are
collected from active service connections which are representative of the
distribution system. - CORRECT ANSWER-Importance of sample site plan
True/False: Keeping the sample in ice or in a cooler prior to and during lab
transport is important because heat stimulates bacterial growth. - CORRECT
ANSWER-True
,What is the action level for lead and copper in mg/L? - CORRECT ANSWER-
Lead: 0.015 mg/L, Copper: 1.3 mg/L
True/False: Low doses of heavy metals like lead and copper can cause damage to
the central nervous system over time. - CORRECT ANSWER-True
What group of bacteria is used to indicate the possible presence of a pathogen? -
CORRECT ANSWER-Coliform
What is the term for the destruction of disease-causing microorganisms? -
CORRECT ANSWER-Pathogens
At room temperature, what form is chlorine in and how does its weight compare
to air? - CORRECT ANSWER-Chlorine is a greenish-yellow gas that is 2.5 times
heavier than air.
What must be kept in stock for disinfecting new water lines as required by the
State? - CORRECT ANSWER-Calcium hypochlorite
True/False: Hypochlorinators consist of a mixing tank and chemical solution feed
pump. - CORRECT ANSWER-True
, When chlorine gas is used, what type of breathing apparatus must be readily
accessible outside the chlorinator room? - CORRECT ANSWER-A full-face self-
contained breathing apparatus (SCBA) or supplied air respirator that meets OSHA
standards
True/False: Is it mandatory for all public water systems to have chlorination
facilities? - CORRECT ANSWER-True
True or False: In Texas, approximately 75% of all water is used for commercial,
industrial, or agricultural purposes. - CORRECT ANSWER-True
What percentage of Earth's surface is covered by water? - CORRECT ANSWER-
71%
Define drought: An extended period when a region experiences a deficiency in its
water supply, which can be atmospheric, ground, or surface water. - CORRECT
ANSWER-
True or False: Only about 1 gallon of tap water per person per day is used for
drinking and cooking. - CORRECT ANSWER-True
