INTERNAL MEMO — DO NOT SEND

Protest 006: DSC 006 — Clay Layer ESU 2C

Date: 2026-03-04
Prepared by: WSDOT Claims Analysis
Subject: Protest 006 — DSC 006 — Clay Layer ESU 2C — Internal Analysis and DRB Preparation
Responding to: Skanska LTR 291 (Dec 8, 2025) — Supplement to Notice of Protest 006

Evaluation Framework

1. Was WSDOT’s position appropriate? YES. The Contract clearly allocates subsurface characterization, interpretation, and design risk to the Design-Builder.
2. Is the Design-Builder’s assertion valid? NO. The conditions do not meet the contractual definition of a DSC. The Design-Builder has not carried its burden of proof.
3. Appropriate path forward? Deny. Reaffirm WSDOT SL 9727-162.

I. Controlling Provisions

II. Why WSDOT’s Position Is Correct

1. Full design responsibility accepted. RFP Section 1-02.1: DB undertakes full responsibility; not excused from Work omitted or misdescribed.
2. Subsurface information provided without warranty. RFP Section 1-02.4(2): no warranty of DB interpretations from GBR or GDR.
3. Section 2.6 does not create a warranty or override risk allocation. RFP Section 2.6 directs the DB to use GDR information as part of its geotechnical evaluation. It does not convert the GDR into a warranty or override the risk allocation in Section 1-02.4(2). SL 242 did not address Skanska’s Section 2.6 argument — the position paper must address this gap.
4. Obligation to investigate, interpret, and supplement. RFP Section 1-02.4 and Section 1-02.4(1): “reasonable investigation” encompasses analysis and interpretation, not merely data collection.
5. GBR controls the DSC baseline. RFP Section 1-02.4(2): GBR takes precedence over GDR when inconsistent.
6. GBR baselined “poor ground” at all depths at these wall locations. GBR Section 3.2.7 (p.9) assigns ground behavior to the DB: “it shall be the Design-Builder’s responsibility to assess these poor ground conditions and their related significance to the structure and the overall design performance to be achieved.” GBR Table 1 (pp.10–11) baselines poor ground in the Sammamish River Valley Area (MP 23.59–24.00) without Footnote 3’s 10-foot depth limit. DSC 006 structures are in this zone.
7. Historical reference information supports foreseeability. Appendix G03 (at DB’s risk per Section 1-02.2) documents a 60-year record: settlement predictions of 1.4–4.0 ft, “2 years required for 90 per cent” consolidation (1966 Foundation Design Recommendations, G03 Vol 1, p.564), sand drain recommendations, and 1956–1967 settlement analyses across the Woodinville Interchange vicinity.
8. Burden of proof lies with the Design-Builder. RFP Section 1-04.7(1): burden not met.

III. Rebuttal of Supplement Arguments

Argument 1: GDR Overburden Errors

DB Position: “Incorrect overburden values” in the GDR are numerical miscalculations, not professional judgment. RFP Section 1-02.4(2).1 does not apply.

Why It Fails: Even if discrepancies exist, Section 1-03.5 required prompt notification and written instructions. The specific discrepancy: GDR consolidation test overburden values of 1060/1065 psf imply a saturated unit weight of ~75 pcf, while laboratory-tested saturated unit weight averaged 113 pcf — error factors of 2.39x and 2.00x inflating reported OCR values. This discrepancy was apparent from the DB’s own work products and should have been recognized per Section 1-02.4(1). Section 1-02.4(2) makes no warranty. Section 2.6 does not override risk allocation.

Argument 2: 245+ Explorations = Reasonable Investigation

DB Position: Volume of post-award testing meets the “reasonable investigation” standard.

Why It Fails: “Reasonable investigation” includes interpretation, not just data collection. No sensitivity analysis demonstrated. Appendix G03 historical settlement data bears on foreseeability.

Argument 3: Settlement Meets DSC Definition

DB Position: Surcharge data and backcalculated parameters show material difference under Section 1-04.7(a) and unusual nature under Section 1-04.7(b).

Why It Fails: “Not discoverable” element not met. G03 historical data includes settlement predictions of 1.4–4.0 ft, year-scale consolidation timeframes, and laboratory-determined consolidation parameters. The DB’s own pre- and post-stone-column CPT investigations show reduced tip resistance within the ESU 2C clay layer following installation, consistent with construction-induced disturbance. The “1.0–1.3” OCR range cited by GeoEngineers may reflect combined effects of soil properties and construction-induced disturbance, not solely in-situ conditions.

Argument 4: “Poor Ground” Classification vs. Magnitude

DB Position: Material difference lies in magnitude, not generic classification.

Why It Fails: GBR Section 3.2.7 does not merely “classify” ground as poor. It expressly assigns the DB responsibility to “assess these poor ground conditions and their related significance to the structure and the overall design performance to be achieved.” “Significance” and “design performance” inherently encompass magnitude and behavior. GBR Table 1 baselines poor ground in the Sammamish River Valley (MP 23.59–24.00) without Footnote 3’s 10-foot depth limit. DSC 006 structures are in this zone.

Argument 5: GDR Is a “Contract Document” per GDM Ch.22 / Section 2.6 Reliance

DB Position: The GDR is a contract document per GDM Section 22-2. Section 2.6 creates a reliance right on GDR data.

Why It Fails: RFP Section 2.6.2.1 (Design-Build Modifications to the GDM) explicitly lists GDM Chapter 22 among provisions that “do not apply to design-build contracts.” The GDR is classified as a Reference Document per Appendix A1, provided at the DB’s risk per Section 1-02.2. Section 2.6 requires the DB to use GDR information but does not convert it into a warranty or override Section 1-02.4(2). The IED (SL 9727-162, Attachment 1, Finding 3) already addressed and rejected this argument.

IV. Fatal Flaw

The GBR, not the GDR, is the baseline for DSC comparison. The GBR baselined the very conditions Skanska is complaining about and placed them within the Design-Builder’s risk allocation.

The DB’s settlement predictions differed from reality because of unconservative parameter selection and interpretation. The DB relied on median values from variable data without demonstrating sensitivity analysis, and did not reconcile discrepancies between unit weights used in other analyses and GDR-reported values. These are investigation and interpretation failures within the DB’s contractual responsibility, not undiscoverable subsurface conditions.

Key Finding: GeoEngineers Appendix A (Timeline of Activities)

GeoEngineers’ own Appendix A (LTR 291, PDF pp.47–49) provides a construction timeline that strengthens WSDOT’s position:

1. Figure 21 proves the post-award investigation changed nothing. Pre-award and post-award settlement predictions are virtually identical (~1 inch post-construction at Abutment 10). Despite 245+ explorations, the DB did not revise GDR-derived parameters. Clearest evidence that “reasonable investigation” consisted of data collection without meaningful interpretation.
2. GeoEngineers controlled the lab testing program. WSDOT SL 9727-149 (Laboratory Testing Package 01) was performed on samples that GeoEngineers personally delivered to WSDOT’s lab. GeoEngineers identified specific portions to test and supplied all testing parameters. WSDOT’s lab executed the protocol GeoEngineers designed. This demonstrates Design-Builder control of the investigation, not WSDOT-directed testing.
3. Construction timeline shows rapid onset. Wall 23.80R construction began 9/2/2024. By 10/18/2024 (46 days), leveling pad poured in the area that would fail. By 10/31/2024, panels tilting 2–5 inches. By 11/6/2024, wall torn down. Rapid onset under normal loading suggests clay compressibility was detectable from the start.
4. Stop-work recommendation preceded DSC notice by 10 days. On 3/22/2025, GeoEngineers recommended stopping work on Abutment 10 and Walls 23.72R/23.73R. First email to WSDOT came 4/1/2025. The DB’s own consultant recognized the broader risk before WSDOT was notified.
5. Surcharge and preload test mirror historical treatments. GeoEngineers recommended a 3-foot gravel surcharge (4/8–6/13/2025) and instrumented preload test (5/21–12/4/2025) — functionally the same as 1960s treatments in Appendix G03. Post-issue response mirroring historical approach reinforces foreseeability.
6. Figure 20 (sensitivity to e₀) is their strongest exhibit but has a counter. Measured field response exceeds even the most pessimistic lab-derived prediction. However, field measurements were taken after stone column installation. The “measured response” curve captures combined in-situ properties AND construction-induced disturbance. CPT evidence (Figures 12–14) supports this interpretation.
7. $25.4M cost claim + 7-month schedule delay (plus AECOM $3.97M + 11-month delay). The magnitude will create sympathy pressure. Position paper must be tight on contractual analysis.

Direction Already Provided

Rebuts any claim that WSDOT has not provided sufficient direction.

WSDOT has provided four written communications over the course of six months, participated in collaborative investigation (including lab testing at GeoEngineers’ direction), and explicitly requested early information sharing.

V. Gaps in DB Submittal

• A. No reconciliation of GDR/analysis discrepancies — GDR overburden values of 1060/1065 psf imply ~75 pcf vs. lab-tested 113 pcf (2.0x–2.4x discrepancy). Should have been identified per Section 1-02.4(1).
• B. No evidence of sensitivity analysis on variable soil parameters. Absence undermines the “unforeseeable” claim.
• C. No discussion of Section 1-03.5 duty to seek written instructions upon discovering apparent errors.
• D. No acknowledgment that GBR (not GDR) establishes the DSC baseline per Section 1-02.4(2).
• E. No analysis of means/methods influence on settlement — pre- and post-stone-column CPT data shows reduced tip resistance in ESU 2C clay, consistent with construction-induced disturbance.

VI. Entitlement Analysis

VII. Recommendation

Option A — Deny and Close. Issue determination denying the protest. Reaffirm SL 9727-162 and risk allocation framework. Cite dispute procedures per RFP Section 1-04.5(1).

Option B (partial acknowledgment) is not recommended. Any concession on the GDR issue risks being read as an admission that WSDOT bears responsibility for Design-Builder interpretations from reference documents.

Correspondence and Events Chronology

INTERNAL MEMO — Prepared 2026-03-01. Hardened 2026-03-04 with pinpoint citations, Section 2.6 paragraph, G03 deep search findings, Footnote 3 zone analysis, GDM Ch.22 rebuttal, and GBR Table 1 baseline. Updated 2026-03-05 with SL 175 39-day timeline, AECOM AESK-0010 R2, GeoEngineers lab control updates, Direction Already Provided table, and full correspondence chronology.