Certified Engineering Geologist (CEG) — California Specialty

Certified Engineering Geologist (CEG) — California Specialty

1. Credential header

• Credential: Certified Engineering Geologist (CEG) — California specialty certification
• Issuing body: California Board for Professional Engineers, Land Surveyors, and Geologists (BPELSG)
• Jurisdiction: California, USA (Washington and Oregon offer their own engineering-geology specialties)
• Level: Specialty certification layered on the California PG — required to practice engineering geology in California
• Prerequisites: California PG (or eligibility), qualifying engineering-geology experience, pass the CEG exam.
• Renewal: Follows the PG renewal cycle; the Renewal Assessment (free, online, state law/rules, within 60 days of expiration every 2 years, effective July 1, 2026) applies to BPELSG licensees. Confirm current requirements with the board.

2. The pathway, step by step

1. California PG. ASBOG FG (140 MC, 4 hrs) + ASBOG PG (110 MC, 4 hrs) + California CSE (3 hours), 3 years experience (see the PG guide).
2. Engineering-geology experience. Responsible-charge work in geologic hazard evaluation, slope stability, fault studies, subsurface characterization for engineering works — documented with references.
3. Pass the CEG exam. CBT at Prometric. Test plan effective January 2025: Project Planning 18%, Data Collection 28%, Interpretation & Reporting 40%, Construction 14%. (Question count and total exam hours were not verified in this pass — confirm with BPELSG/Prometric before scheduling.)
4. Apply to BPELSG for the specialty certification.

3. What the CEG restricts

California requires the CEG specialty to practice engineering geology. General geologic work runs under the PG; the moment the work is engineering geology — evaluating geologic hazards for design, characterizing the ground for foundations and slopes, fault-rupture and seismic-hazard studies under SHMA/Alquist-Priolo — the CEG is required. This is the sharpest scope boundary in the California geo-professions:

• PG (without CEG): general geology, groundwater, environmental site assessment, mineral resources.
• CEG: engineering geology — slope stability evaluations, landslide mapping, fault investigations, seismic hazard reports, geologic input to grading and foundation design.
• PE/GE (civil/geotechnical engineer): engineering design and analysis — the engineer takes the CEG's geologic model and designs the mitigation.

Every SHMA or Alquist-Priolo report filed in California carries CEG (and usually GE) responsible charge. The two professions are complementary by statute and by practice.

4. Exam structure and strategy

The January 2025 test plan weights tell you exactly how to allocate study: Interpretation & Reporting at 40% is the exam's center of gravity — taking field and lab data and producing defensible geologic models, hazard evaluations, and written reports. Data Collection (28%) is field methods; Project Planning (18%) is scope, standards of care, and regulatory triggers; Construction (14%) is observation, mapping, and change conditions during grading.

Strategy: study backwards from the report. For every method (trenching, drilling, geophysics, lab testing), know what it tells you, what it can't tell you, and how its results appear in a hazard evaluation. The exam tests the complete workflow — plan the investigation, collect the data, interpret it, write it up, observe construction — and penalizes candidates who know methods but can't synthesize.

5. Knowledge domains (by test-plan weight)

5.1 Interpretation & Reporting (40%)

• Geologic models: from borings, trenches, and outcrops to cross-sections — projecting contacts, honoring structure, quantifying uncertainty. The exam tests whether your section is geologically reasonable (contacts follow structure; no floating lenses without evidence).
• Slope stability evaluation: recognizing failure modes from geomorphology (headscarps, hummocky terrain, jackstrawed trees), selecting analysis sections, parameter selection from lab/field data, interpreting FS results against regulatory thresholds (1.5 static, 1.1 pseudo-static typical).
• Fault evaluation: trench logging (stratigraphic offset, colluvial wedges, upward terminations), distinguishing active vs. inactive faulting, age-dating (radiocarbon, soil development), setback recommendations under Alquist-Priolo.
• Liquefaction/lateral spreading: SPT/CPT-based triggering, settlement estimates, hazard mapping for SHMA reports.
• Report writing: the CEG report must state the scope, methods, findings, opinions, recommendations, and limitations — with uncertainty quantified, not hidden. The exam tests report adequacy against the standard of care.

5.2 Data Collection (28%)

• Subsurface exploration: drilling methods (hollow-stem auger, mud rotary, sonic — selection by geology and objective), SPT, CPT, sampling (California sampler, Shelby tubes, pitch barrels); logging standards (USCS, consistency/density descriptors).
• Trenching: the signature CEG method — fault trenches (perpendicular to strike, deep enough to expose the full stratigraphic section), landslide trenches; logging at 1:60 or larger scale, photomosaics.
• Geophysics: seismic refraction/reflection (rippability, depth to bedrock), resistivity (groundwater, clay zones), GPR (shallow voids/utilities) — know what each method resolves and its depth limits.
• Remote sensing: LiDAR bare-earth DEMs (the landslide mapper's primary tool — hummocky topography and scarps invisible under vegetation), aerial photo interpretation (stereo pairs, temporal sequences showing movement), InSAR for slow creep.
• Lab testing: index tests (Atterberg, gradation), strength (direct shear, triaxial), consolidation — selection and interpretation, not procedure memorization.

5.3 Project Planning (18%)

• Regulatory triggers: when SHMA requires investigation (development in a mapped hazard zone), when Alquist-Priolo applies (structures for human occupancy in an EFZ), DSOD jurisdiction, local grading ordinances.
• Scope development: matching investigation intensity to hazard and project risk — a single-family home on flat ground vs. a hillside subdivision vs. a hospital.
• Standard of care: what the reasonably prudent CEG does — literature review (geologic maps, prior reports), field reconnaissance, then subsurface work; the exam penalizes skipping steps.
• Contracts and liability: limitation of liability, differing site conditions, the CEG's duty to warn of hazards.

5.4 Construction (14%)

• Grading observation: the CEG observes cuts as they're opened — confirming the geologic model, mapping exposed contacts and landslides, recommending keyway/benching and removals.
• Changed conditions: when the ground differs from the model (unmapped landslide, fault splay, worse bedrock) — stop-work authority concepts, supplemental investigation, redesign coordination with the GE.
• Mitigation construction: landslide repair observation (subdrain installation, shear key excavation), fault setback verification, compaction testing coordination.

6. Key methods reference (units + selection logic)

• Trenching: fault studies (perpendicular to strike), landslide confirmation; scale ≥ 1:60 logging.
• SPT/CPT: triggering analysis input — (N1)60, qc1N, Ic; fines corrections.
• LiDAR: bare-earth DEM resolution ~1 m or better for scarp morphology.
• Seismic refraction: depth to bedrock/rippability; needs velocity contrast.
• Direct shear / triaxial: c', φ' for stability; residual strength for reactivated landslides (use residual, not peak, on pre-sheared surfaces — a classic exam trap).
• Radiocarbon: datable to ~50 ka; calibrates fault recency.

7. Worked examples

Example 1 — Trench evidence and fault recency

A fault trench exposes: Unit A (colluvium, unfaulted, C-14 dated 8 ka) overlying Unit B (alluvium, faulted, 15 ka) with a colluvial wedge banked against the fault scarp within Unit B.

Interpretation: the most recent event occurred after 15 ka (faults B) and before 8 ka (A unfaulted seals it) — bracketed between 8 and 15 ka. The colluvial wedge is the event horizon marker. Under Alquist-Priolo, a fault with displacement in the Holocene (< 11.7 ka) is zoned; this event may be Holocene — the CEG recommends additional dating to resolve the bracket, and the setback applies conservatively in the interim. The exam tests this bracketing logic relentlessly.

Example 2 — Residual vs. peak strength on a reactivated slide

Direct shear on slip-surface material: peak c' = 200 psf, φ' = 24°; residual φ'r = 14°, c'r ≈ 0. The slide moved in 1998 and 2005.

For stability analysis of the reactivated slide, use residual strengths — the slip surface is pre-sheared; peak strength no longer exists there. Infinite-slope check with z = 12 ft, β = 18°, γ = 125 pcf, seepage at surface: u = 62.4×12×cos²18° = 62.4×12×0.905 = 678 psf; FS = [(125×12×0.905 − 678) tan14°] / (125×12×sin18°cos18°) = [(1357 − 678)(0.2493)] / (1500×0.309×0.951) = 169.3/440.8 = 0.38 — actively unstable, consistent with the movement history. Using peak strength would have given a misleading FS > 1 — the exam's favorite strength-selection trap.

Example 3 — LiDAR-based landslide mapping scope

A 50-acre hillside subdivision proposal in the Santa Monica Mountains. Planning-level scope:

1. Literature: Dibblee/CGS geologic maps, prior landslide maps, historic aerials (temporal — look for pre-development scarps).
2. LiDAR bare-earth DEM: map headscarps, lateral margins, hummocky deposits; classify activity (active/dormant/relict) by morphology freshness.
3. Field reconnaissance: confirm LiDAR picks, map springs/seeps, distress in existing improvements.
4. Subsurface: borings/CPT through the slide mass to locate the basal rupture (shear strength sampling), trenches across the headscarp.
5. Analysis + report: stability sections, FS vs. thresholds, mitigation (buttress, shear pins, drainage) or avoidance. The exam tests scope sequencing — LiDAR before drilling, reconnaissance before trenching — and penalizes inverted scopes.

8. Standards and regulations cross-reference

• SHMA (1990) (geotechnical-reg-019): investigation and mitigation requirements in liquefaction/landslide zones — the CEG's primary regulatory driver.
• Alquist-Priolo (1972) (geotechnical-reg-020): fault investigation, trenching, setbacks — the CEG's signature work product.
• ASTM D1586/D5778/D2487 (geotechnical-std-012/013/014): SPT, CPT, USCS — shared field canon.
• CGS Special Publications and Notes (practice references): fault evaluation, landslide mapping, LiDAR guidelines — know they exist and govern California practice.
• OSHA 29 CFR 1926 Subpart P (geotechnical-std-018): trench/excavation safety for the CEG's own fieldwork.

9. Pitfalls and exam strategy

• 40% is interpretation: method trivia without synthesis fails. Practice writing the conclusion from a data set, not just naming the method.
• Residual strength on old slides: pre-sheared surface → residual parameters. Peak strength on a reactivated landslide is the exam's most reliable wrong answer.
• Bracketing fault age: unfaulted unit above = younger bound; faulted unit below = older bound. Draw the stratigraphic column if confused.
• LiDAR first, drilling second: scope-sequencing questions reward the cheapest-informative-first order.
• Uncertainty in reports: the standard of care requires stating limitations — an exam answer that presents a geologic model as certain fails the professional-judgment questions.
• Unverified exam length: the question count and hours were not verified in this pass — confirm with BPELSG/Prometric when scheduling, and pace by the test-plan weights regardless.

10. Practice problems

1. Trench: faulted Unit X (20 ka), unfaulted Unit Y (5 ka) above. Event bracket? Holocene-active? (Answer: 5–20 ka; Holocene is < 11.7 ka — the bracket straddles it; additional dating needed; treat as active pending resolution.)
2. Infinite slope: β = 22°, z = 10 ft, γ = 120 pcf, residual φ'r = 16°, c' = 0, dry. FS? (Answer: FS = tan16°/tan22° = 0.2867/0.4040 = 0.71 — unstable.)
3. Which investigation method for: (a) fault location, (b) depth to bedrock over 5 acres, (c) shallow voids? (Answer: (a) trenching perpendicular to strike; (b) seismic refraction; (c) GPR.)
4. A 1990s landslide repair is proposed for reactivation analysis. Peak or residual strength? (Answer: residual — pre-sheared surface.)
5. List the CEG report's required elements. (Answer: scope, methods, findings/data, geologic model, hazard evaluation, opinions, recommendations, limitations/uncertainty.)

File: geotechnical/certified-engineering-geologist-ceg-california-specialty-study-guide.md Sources: catalogue records geotechnical-cert-004, geotechnical-std-012/013/014/018, geotechnical-reg-019/020; CEG test-plan weights (18/28/40/14, effective Jan 2025) and CBT-at-Prometric format verified via board-published materials (2026-09-30). Question count and exam hours: NOT verified — confirm with BPELSG/Prometric.

Original ETS reference writing, verified against public sources on 2026-09-30. Thin sourcing is flagged inline. Not legal advice — confirm current editions with the issuing body.