The Texas General Well Driller exam is a closed-book PSI test with 60 scored plus 5 non-scored items in a total of 120 minutes, and you need 70% to pass. Its content is weighted toward Texas law and rule (20 items) and groundwater protection (15 items), with safety, hydrology and geology, and rigs making up the rest. You cannot schedule until TDLR approves your license application, so start with the application and experience documentation, then study the official references named in the PSI candidate bulletin for each weighted area.
What the exam covers and how the content is weighted
The General Well Driller exam tests five subject areas, with Texas law and rule and groundwater protection together accounting for more than half of the scored items.
The Texas Department of Licensing and Regulation (TDLR) lists the TX General Well Driller test among its Water Well Driller endorsement examinations, delivered through the testing vendor PSI. The PSI candidate bulletin for this exam states the exact content outline and item counts, so you can plan study time against real weights rather than guesses.
Note the framing: General Well Driller is an endorsement examination within TDLR's licensing program, not a standalone license title. Your application, not this exam alone, determines the license type and endorsements you hold.
| Subject area | Scored items |
|---|---|
| Texas Law and Rule | 20 |
| Groundwater Protection | 15 |
| Safety | 10 |
| Hydrology and Geology | 10 |
| Rigs | 5 |
Sources: Water Well Driller and Pump Installer Licensing Examination (TDLR) — Exam eligibility, endorsement exam list, retake and eligibility-validity rules; PSI Texas well driller candidate bulletin — General Well Driller content outline, format, fees, reference lists; endorsement exam outlines
Apply first: the approval steps before you can schedule
You must submit a license application and have TDLR verify your eligibility before PSI will let you register and schedule the exam.
TDLR's exam page is explicit about the order: applicants submit an application first, TDLR staff verify that you meet the eligibility requirements, and only then do you receive an eligibility email from PSI with instructions for registering and scheduling. Eligibility is valid for one year from the date of approval, so plan your study and test date inside that window.
For the underlying license, TDLR requires a minimum of two years of relevant experience under the supervision of a licensed Well Driller or Pump Installer. Your qualifying installations or drillings must be documented on the Well Driller and Pump Installer Experience Verification Form, completed by your supervising licensee, or by a supervisor letter describing your experience for each period of employment.
- Submit the Well Driller and/or Pump Installer License Application with the correct non-refundable fee.
- Document two years of supervised experience with the Experience Verification Form or supervisor letters.
- Schedule with PSI promptly after approval so your one-year eligibility window does not lapse.
Sources: Water Well Driller and Pump Installer Licensing Examination (TDLR) — Exam eligibility, endorsement exam list, retake and eligibility-validity rules; Apply for a New Water Well Driller and/or Pump Installer License (TDLR) — Experience requirements, qualifying drillings tables, application fees, criminal convictions
Format, fees, and retakes
The closed-book General exam has 60 scored items plus five non-scored items, with 120 minutes total. The passing standard is 70% correct on the scored items.
The PSI bulletin states the format precisely: 60 scored items with 110 minutes, 5 additional non-scored items with 10 minutes, and a passing standard of 70% correct. Non-scored items are unscored pretest questions mixed into the sitting, so answer every item as if it counts.
The exam is closed book, and the bulletin adds a rule worth internalizing: do not consider code exceptions unless a question specifically directs you to. Answer from the general requirements in your studied references rather than hunting for edge-case exceptions.
If you fail, you may schedule a retake with PSI within 24 to 48 hours of the failed exam, provided your eligibility has not expired. The $52 examination fee is charged per sitting.
Sources: Water Well Driller and Pump Installer Licensing Examination (TDLR) — Exam eligibility, endorsement exam list, retake and eligibility-validity rules; PSI Texas well driller candidate bulletin — General Well Driller content outline, format, fees, reference lists; endorsement exam outlines
Texas law and rule: the largest content area
Twenty of the sixty scored items come from Texas law and rule, so the Occupations Code and the administrative rules deserve the largest share of your study time.
The bulletin names two primary sources for this area: Texas Occupations Code, Chapter 1901, which governs water well drillers, and Title 16 Texas Administrative Code, Chapter 76, the state's water well driller rules. Both are available free online through the links in the bulletin's reference list.
Read the statute and rules themselves rather than summaries. Because this area carries the heaviest weight, plan to work through Chapter 76 section by section and note which provisions describe duties you would perform on a job. This guide does not restate the rules; the current administrative text is the controlling source for their content.
Hydrology, geology, and groundwater protection
These two areas total 25 scored items and reward understanding how drilling methods interact with formations and how finished wells are evaluated and protected.
The bulletin's reference list for this exam includes Aquifers of Texas (Report 380, TWDB, 2011) and Groundwater and Wells, third edition. Standard hydrology references describe the common well construction methods in consistent terms: bored wells use earth augers, driven wells use a casing with a screened drive point, jetted wells excavate with a high-pressure jet, cable-tool (percussion) drilling repeatedly lifts and drops a chisel bit and bails out the slurry, hydraulic rotary circulates mud either down the pipe (normal) or down the annulus (reverse), and air rotary works like hydraulic rotary but uses air as the fluid.
The same fundamentals explain two post-construction concepts. Well development is the phase after construction that removes clay, silt, and fine sand from beside the screen or open hole so the well produces sediment-free water. Specific capacity expresses a well's yield per unit of drawdown, calculated by dividing the pumping rate by the drawdown measured at the same time in the test.
Groundwater protection, at 15 items, is the second-heaviest area. TDLR's program pages point to the state's well construction and plugging specifications as core program material, so treat the current Chapter 76 provisions on construction and plugging as your primary study text for this area.
Practice
During a constant-rate test on a completed well, both of the following readings are taken 60 minutes after the pump started: a pumping rate of 50 gallons per minute and a drawdown of 10 feet. What is the well's specific capacity at that point in the test?
Show answer
5 gallons per minute per foot of drawdown.
Specific capacity is the yield per unit of drawdown, so divide the pumping rate by the drawdown, using readings taken at the same elapsed time: 50 ÷ 10 = 5 gpm per foot. Dividing the other way gives 0.2 feet per gallon per minute, which is the inverted ratio and not specific capacity. Keep the scope in mind too: a specific capacity figure from one moment describes that well at that time and does not by itself establish the aquifer's long-term sustainable yield or select a pump.
Sources: Water Well Driller and Pump Installer Licensing Examination (TDLR) — Exam eligibility, endorsement exam list, retake and eligibility-validity rules; PSI Texas well driller candidate bulletin — General Well Driller content outline, format, fees, reference lists; endorsement exam outlines; USGS Water-Supply Paper 2220, Basic Ground-Water Hydrology — Selected fundamentals: well construction methods, well development, specific capacity
Safety and rigs: study the named OSHA subparts
Safety (10 items) and rigs (5 items) are best prepared by working directly through the OSHA subparts and drilling references named in the bulletin.
The bulletin's reference list names specific OSHA standards for this exam: occupational noise exposure (1910.95), control of hazardous energy or lockout/tagout (1910.147), derricks (1910.181), slings (1910.184), selection and use of work practices (1910.333), machine guarding (1917.151), safety belts, lifelines, and lanyards (1926.104), jacks—lever, ratchet, screw, and hydraulic (1926.305), duty to have fall protection (1926.501), and wire rope inspection (1926.1413). These citations tell you exactly which federal texts to read; they do not summarize the rules, so read each subpart itself.
For rigs, the bulletin also lists The Drilling Manual, 5th Edition. Use it and your supervised field experience together: paper study covers the tested knowledge, but it cannot substitute for supervised practical competence around rig equipment.
For revision, connect each named safety standard to the hazard it addresses, then read the actual requirement in that standard. The reference list identifies study material; it does not replace the text.
- Read each named OSHA subpart and note the hazard it controls and the requirement it imposes.
- Pair The Drilling Manual's rig chapters with the safety subparts so equipment and safe practice are learned together.
- Remember the closed-book rule: you need these requirements in memory, not in a book you can open.
How this exam fits with the other Texas driller exams
General Well Driller is one of six TDLR driller endorsement examinations; the others have their own outlines, item counts, and fees, and pump installer work is a separate license track.
TDLR's endorsement examinations for drillers are the Closed Loop Geothermal, Dewatering, General, Injection, Monitor Well, and Water Well Driller exams. You select endorsements on your licensing application, and the exam you take depends on your license class and selected endorsements.
Do not confuse the General exam with the Water Well Driller exam. The Water Well Driller exam has 70 scored items in 112 minutes and is weighted heavily toward design, construction, and completion, while the General exam is the 60-item law-and-protection-weighted test described above. Adding a later endorsement to an existing license means a new application, proof of the qualifying drillings for that endorsement, and a $25 fee.
Pump work sits on a separate track entirely, with its own endorsement examinations such as Single Phase Pump, Three-Phase Pump, General Pump Installer, Line Shaft Turbine Pump, and Windmills, Hand Pump and Pump Jack. If your work includes pumping equipment, plan for the pump installer application and exam path as well.
The endorsement outlines differ. Water Well assigns 35 scored items to design/construction/completion, 12 to geology/hydrology, four to rehabilitation, 15 to law/rule and four to safety. Monitor Well uses 34 construction, 12 geology/hydrology, 15 law/rule and four safety. Closed Loop uses 22 construction, six law/rule and two safety; its construction topics include loop installation, pipe fusion and grouting. Injection and Dewatering each use 16 construction, six geology/hydrology, six law/rule and two safety. All these bulletins specify 70% to pass.
| Exam | Scored + non-scored items | Total time |
|---|---|---|
| General | 60 + 5 | 120 min |
| Water Well | 70 + 5 | 120 min |
| Monitor Well | 65 + 6 | 120 min |
| Closed Loop Geothermal | 30 + 3 | 60 min |
| Injection | 30 + 3 | 60 min |
| Dewatering | 30 + 3 | 60 min |
Sources: Water Well Driller and Pump Installer Licensing Examination (TDLR) — Exam eligibility, endorsement exam list, retake and eligibility-validity rules; Apply for a New Water Well Driller and/or Pump Installer License (TDLR) — Experience requirements, qualifying drillings tables, application fees, criminal convictions; PSI Texas well driller candidate bulletin — General Well Driller content outline, format, fees, reference lists; endorsement exam outlines
Preparation checklist and next steps
Sequence your effort: application and experience documentation first, then law and groundwater protection, then the technical and safety areas, all from the official references.
Because PSI will not schedule you until TDLR approves your application, the administrative steps are your true starting point. Confirm which license type and endorsements fit your work before you apply, since the qualifying drilling counts and fees differ by license type.
- Submit the license application with experience verification and the correct fee, and answer the conviction question.
- After TDLR approval, schedule inside the one-year eligibility window.
- Allocate the most study time to Texas Occupations Code Chapter 1901 and 16 TAC Chapter 76, the heaviest and second-heaviest areas.
- Study the named OSHA subparts and The Drilling Manual for the safety and rigs areas.
- Work through the named hydrology references and practice specific-capacity style calculations.
- Download the current Candidate Information Bulletin from TDLR's exam page to confirm the outline, fees, and site details before your test date.
Sources: Water Well Driller and Pump Installer Licensing Examination (TDLR) — Exam eligibility, endorsement exam list, retake and eligibility-validity rules; Apply for a New Water Well Driller and/or Pump Installer License (TDLR) — Experience requirements, qualifying drillings tables, application fees, criminal convictions; PSI Texas well driller candidate bulletin — General Well Driller content outline, format, fees, reference lists; endorsement exam outlines; USGS Water-Supply Paper 2220, Basic Ground-Water Hydrology — Selected fundamentals: well construction methods, well development, specific capacity
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