100+ Free REP Practice Questions

Pass your NREP Registered Environmental Professional exam on the first try — instant access, no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately

Not published by NREP Pass Rate

100+ Questions

100% Free

1 / 10

Question 1

Score: 0/0

Under ASTM E1527-21, what is the maximum viability period of a Phase I Environmental Site Assessment (ESA) for it to qualify for CERCLA All Appropriate Inquiries (AAI) landowner liability protections?

90 days from date of first completion task

180 days with prescribed updates for certain components

One year with no update requirements

Two years provided the site has not changed

to track

2026 Statistics

Key Facts: REP Exam

100

Practice Questions

OpenExamPrep REP Bank

MS/PhD

Typical Education

NREP REP Requirements

2 yrs min

Experience Required

NREP (senior-level)

$78,980

Median Wage (Env Scientist)

BLS OES May 2023

Projected Job Growth 2022-2032

BLS OOH

Annual

CEU Renewal Cycle

NREP

The NREP REP is a senior-level credential for experienced environmental professionals with a graduate degree (or qualifying license) and substantial senior-level experience. U.S. Bureau of Labor Statistics reports ~85,100 environmental scientists/specialists nationally with a median wage of ~$78,980 (May 2023); senior practitioners (90th percentile) earn over $129,000 with many exceeding $150,000 in consulting/corporate leadership roles. BLS projects 6% employment growth 2022-2032 — faster than average — driven by climate, ESG reporting, PFAS remediation, and due diligence demand. The REP signals senior-tier expertise above the REM precursor.

Sample REP Practice Questions

Try these sample questions to test your REP exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1Under ASTM E1527-21, what is the maximum viability period of a Phase I Environmental Site Assessment (ESA) for it to qualify for CERCLA All Appropriate Inquiries (AAI) landowner liability protections?

A.90 days from date of first completion task

B.180 days with prescribed updates for certain components

C.One year with no update requirements

D.Two years provided the site has not changed

Explanation: A Phase I ESA is viable for 180 days from the earliest date of the five key components (regulatory records review, site reconnaissance, interviews, title search, and declaration by the environmental professional). If older than 180 days but less than one year, the four prescribed components must be updated. Over one year, a new Phase I is required for AAI compliance.

2Which of the following is the correct definition of a Recognized Environmental Condition (REC) under ASTM E1527-21?

A.Any historical use of hazardous substances regardless of current site status

B.The presence or likely presence of hazardous substances or petroleum products in, on, or at a property due to a release, likely release, or material threat of a future release

C.Contamination that has been fully remediated and closed by the regulatory agency

D.De minimis conditions that do not pose a material risk of exposure

Explanation: Per ASTM E1527-21, a REC is the presence or likely presence of hazardous substances or petroleum products in, on, or at a property: (1) due to a release to the environment, (2) under conditions indicative of a release, or (3) under conditions that pose a material threat of a future release. De minimis conditions are explicitly excluded from RECs.

3A Phase I ESA identifies historical soil contamination from a former underground storage tank that was removed in 1995. Soil samples confirmed contamination exceeded state cleanup standards at the time. The site received a No Further Action letter with a deed restriction prohibiting residential use and requiring maintenance of a vapor barrier. What is the appropriate classification under ASTM E1527-21?

A.Recognized Environmental Condition (REC)

B.Historical Recognized Environmental Condition (HREC)

C.Controlled Recognized Environmental Condition (CREC)

D.De minimis condition

Explanation: A CREC is a past release that has been addressed to the satisfaction of the regulatory authority with hazardous substances allowed to remain in place subject to an activity and use limitation (AUL) or engineering/institutional control. The deed restriction and vapor barrier requirement constitute controls that must be maintained, making this a CREC. An HREC would apply only if residual contamination met unrestricted use criteria.

4Under the EPA AAI rule (40 CFR Part 312), which of the following must the environmental professional include in the Phase I ESA declaration?

A.A guarantee that no contamination exists on the property

B.A statement of qualifications and a declaration that the assessment meets the definition of an environmental professional and AAI standards

C.A certified laboratory report from site sampling

D.An ASTM membership number

Explanation: 40 CFR 312.21 requires the environmental professional to provide a signed declaration attesting to their qualifications (license/registration, education, and experience) and that the assessment was performed in conformance with the AAI rule. The declaration does not require sampling (Phase I is non-intrusive) and cannot guarantee the absence of contamination.

5Historical land use research for a Phase I ESA under ASTM E1527-21 must extend back to what point in time?

A.The past 20 years only

B.The year 1940 only

C.The property's first developed use or back to 1940, whichever is earlier

D.The past 50 years regardless of development history

Explanation: ASTM E1527-21 requires historical use research back to the property's first developed use, or back to 1940, whichever is earlier. This helps identify past industrial, commercial, or agricultural uses that may have contributed to contamination. Sources include Sanborn maps, aerial photographs, city directories, and topographic maps.

6During a Phase II ESA, a Data Quality Objective (DQO) process is used to:

A.Select the lowest-cost laboratory

B.Define the type, quantity, and quality of data needed to support defensible decisions

C.Determine which contaminants are regulated

D.Eliminate the need for a QA/QC plan

Explanation: The EPA's 7-step DQO process (QA/G-4) defines the problem, identifies goals, inputs, study boundaries, analytical approach, acceptable limits on decision errors, and optimized design. DQOs ensure data are of sufficient quality and quantity to support project decisions, and they drive MDL/RL selection, sampling density, and QA/QC sample frequency.

7The Method Detection Limit (MDL) is best defined as:

A.The lowest concentration at which the laboratory routinely reports results

B.The minimum concentration of a substance that can be measured and reported with 99% confidence that the analyte concentration is greater than zero

C.The cleanup goal set by the regulator

D.The concentration at which human health effects occur

Explanation: Per 40 CFR Part 136 Appendix B, the MDL is the minimum concentration of a substance that can be measured and reported with 99% confidence that the analyte concentration is greater than zero. The reporting limit (RL) or quantitation limit (PQL) is typically 3-10 times the MDL and represents the lowest concentration that can be reliably quantified.

8A baseline human health risk assessment under EPA Risk Assessment Guidance for Superfund (RAGS) follows which four-step framework?

A.Planning, execution, review, and closure

B.Data collection/evaluation, exposure assessment, toxicity assessment, and risk characterization

C.Hazard identification, mitigation, verification, and monitoring

D.Source, pathway, receptor, and control

Explanation: EPA's baseline human health risk assessment follows NAS/NRC's four-step framework codified in RAGS Part A: (1) Data collection and evaluation (hazard identification), (2) Exposure assessment, (3) Toxicity assessment, and (4) Risk characterization. This produces cancer risk (CR) and non-cancer hazard quotient (HQ) estimates.

9For a non-carcinogenic chemical exposure, the Hazard Quotient (HQ) is calculated as:

A.Exposure dose divided by the reference dose (RfD)

B.Cancer slope factor multiplied by exposure dose

C.Exposure concentration divided by the LC50

D.MDL divided by the regulatory limit

Explanation: HQ = Exposure Dose / RfD (or Exposure Concentration / RfC for inhalation). An HQ above 1.0 indicates potential for adverse non-cancer health effects. For multiple chemicals affecting the same target organ, HQs are summed to compute a Hazard Index (HI). Cancer risk is calculated separately using the slope factor (CSF): Risk = Dose × CSF.

10An incremental lifetime cancer risk of 3 × 10⁻⁵ for a site means:

A.3 out of 1,000 exposed individuals will develop cancer

B.3 out of 100,000 additional cancer cases are estimated over a lifetime of exposure

C.The site poses no cancer risk

D.3% of exposed individuals will develop cancer

Explanation: 3 × 10⁻⁵ equals 3 in 100,000 additional (incremental) lifetime cancer cases above background over a standard 70-year lifetime. EPA's acceptable risk range under CERCLA is 10⁻⁴ to 10⁻⁶. This value exceeds the 10⁻⁶ point-of-departure and typically warrants response action evaluation, though it falls within the CERCLA risk management range.

About the REP Exam

The NREP Registered Environmental Professional (REP) is an advanced, senior-level credential for experienced environmental practitioners with graduate degrees (MS/PhD) or qualifying professional licenses (CIH, CSP, CHMM, CEP, CET) plus substantial senior-level environmental work experience. The REP recognizes expertise across environmental due diligence, risk assessment, remediation, multi-media regulatory compliance, NEPA and state environmental review, climate regulation, and ESG reporting — positioning holders for senior consulting, corporate environmental leadership, and M&A due diligence roles.

Assessment

100 multiple-choice questions (senior-level) spanning environmental due diligence (ASTM E1527-21, AAI), risk assessment, remediation, multi-media compliance, NEPA, climate regulations, and ESG/sustainability

Time Limit

2 hours

Passing Score

70% (where exam component applies)

Exam Fee

$295-$395 (NREP (National Registry of Environmental Professionals))

REP Exam Content Outline

~20%

Environmental Due Diligence

ASTM E1527-21 Phase I ESA, AAI rule (40 CFR 312), RECs/CRECs/HRECs, historical land use, Phase II sampling plans, QA/QC, M&A due diligence, CERCLA landowner defenses (BFPP, CPO, ILO)

~15%

Risk Assessment

EPA RAGS framework, exposure assessment (RME, CTE), RfD/RfC, cancer slope factor, HQ/HI, cancer risk, EPA RSLs, vapor intrusion screening, cumulative and mixtures risk

~18%

Remediation Technologies

ISCO (persulfate, permanganate, Fenton's), enhanced reductive dechlorination (Dhc bioaugmentation), thermal (ERH/TCH/SEE), SVE/AS, MPE, PRB/ZVI, phytoremediation, MNA lines of evidence, PFAS treatment (GAC, IX, RO), NCP 9-criteria remedy selection

~15%

Multi-Media Regulatory Compliance

CAA (NSR, Title V, NESHAP), CWA (NPDES, SPCC, 404 wetlands), RCRA (generator categories, LDR, corrective action), TSCA (PCBs, PFAS), EPCRA (TRI, Tier II), CERCLA, OSHA HAZWOPER, ESA Section 7, NHPA Section 106

~10%

NEPA and State Environmental Review

EA/EIS/CatEx, tiering, alternatives analysis, cumulative impacts, mitigated FONSI, mitigation monitoring, environmental justice (EO 12898, 14008, 14096, Justice40), CEQA (EIR, baseline), SEQR (Pos Dec, Neg Dec)

~10%

Climate Regulations

EPA GHG Reporting (40 CFR 98, 25,000 tCO2e/yr threshold), SEC climate disclosure rule, California SB 253/261, IRA methane fee, cap-and-trade (CARB, RGGI), SBTi, scenario analysis

~12%

Sustainability and ESG Reporting

GRI (impact materiality), SASB (financial materiality), TCFD/IFRS S2, ESRS/CSRD double materiality, GHG Protocol (Scopes 1/2/3), ISO 14001 EMS, LCA (ISO 14040/14044), EPDs (ISO 14025), EPR laws, circular economy

How to Pass the REP Exam

What You Need to Know

Passing score: 70% (where exam component applies)
Assessment: 100 multiple-choice questions (senior-level) spanning environmental due diligence (ASTM E1527-21, AAI), risk assessment, remediation, multi-media compliance, NEPA, climate regulations, and ESG/sustainability
Time limit: 2 hours
Exam fee: $295-$395

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

REP Study Tips from Top Performers

1Master ASTM E1527-21 cold — know the differences between REC, CREC, HREC, de minimis condition, and vapor encroachment condition (VEC); this appears throughout senior-level practice

2Memorize the CERCLA 9 evaluation criteria (2 threshold: Overall Protection, ARARs | 5 balancing | 2 modifying) and NCP's remedy selection framework — expect application-based scenario questions

3Know the 25,000 tCO2e/yr GHG reporting threshold (40 CFR 98) and how SEC climate disclosure, California SB 253/261, and IFRS S2 differ — senior practitioners advise on all three

4Practice HQ (Dose/RfD) and cancer risk (Dose × CSF) calculations plus EPA acceptable risk range (10⁻⁴ to 10⁻⁶) — senior risk assessors must compute these under pressure

5Understand double materiality (CSRD/ESRS) versus single-axis materiality (SASB financial / GRI impact) — this is the dominant distinction in modern ESG reporting

Frequently Asked Questions

What is the NREP Registered Environmental Professional (REP) credential?

The REP is a senior-level NREP credential for experienced environmental practitioners. It recognizes advanced expertise across environmental due diligence, risk assessment, remediation, multi-media compliance, NEPA, climate regulations, and ESG reporting. NREP positions REP as an advanced credential designed for experienced professionals — not entry-level practitioners.

REP vs REM — how do they differ?

REM (Registered Environmental Manager) is the broader, mid-level management credential from NREP, typically requiring a bachelor's degree plus 5 years of directly related environmental experience and a 100-question exam. REP (Registered Environmental Professional) is positioned as more senior — typically requiring a graduate degree (Master's/Doctorate) in an environmental field (or qualifying professional license like CIH/CSP/CHMM) plus at least 2 years of senior-level experience. Many practitioners earn REM first as a precursor to REP.

What are the eligibility requirements for REP?

Per NREP: a Master's or Doctorate degree in an environmentally related field from an accredited institution (MBAs are not accepted) OR a qualifying professional license (CIH, CSP, CHMM, CEP, CET, among others listed by NREP), plus a minimum of 2 years of relevant senior-level environmental work experience. Many senior practitioners hold equivalent profiles of BS + 10 years or MS + 8 years of professional practice.

Is there an exam for REP?

NREP's REP is primarily an application-based credential with credential committee review of education, professional license, and senior-level experience documentation. When an assessment component applies, it typically consists of 100 multiple-choice questions delivered via online proctoring with a 70% passing standard. Always confirm current exam/application requirements directly with NREP.

How much does the REP credential cost?

NREP REP application fees are typically in the $295-$395 range. Annual renewal requires a renewal fee plus documentation of Continuing Education Units (CEUs). Confirm the current fee schedule directly with NREP at customerservice@nrep.org or 814-680-6232, as fees may change.

How do I maintain the REP credential?

REP renewal is annual — candidates must submit CEUs each year to maintain the credential. NREP does not permit renewal through re-examination alone — ongoing continuing education is mandatory. Approved CEUs include relevant professional development, technical training, conference attendance, authored publications, and teaching at recognized environmental programs.

What regulations and frameworks does the REP cover?

The REP spans federal environmental statutes (CAA, CWA, RCRA, CERCLA, TSCA, EPCRA, NEPA, ESA, NHPA, SDWA), key state programs (CEQA, SEQR, California climate disclosure SB 253/261, SCP), ASTM standards (E1527-21 Phase I ESA, E2600 vapor encroachment, E1903 Phase II), EPA RAGS risk assessment guidance, and emerging ESG/climate frameworks (TCFD, IFRS S2, GRI, SASB, ESRS/CSRD, SBTi, GHG Protocol).

What careers does the REP credential support?

REP holders typically serve as senior environmental consultants, practice leaders, corporate environmental directors/VPs, M&A due diligence leads, sustainability/ESG directors, and expert witnesses. Per BLS (May 2023), environmental scientists/specialists earn a median wage of ~$78,980, with senior practitioners (90th percentile) exceeding $129,000 — many REP-holding consulting principals and in-house corporate leaders earn $150K+.