System

{{entity:Radiochemistry Laboratory}} for a UK Nuclear Dockyard v2 (project se-radiochem-lab-v2). Full QC review triggered by first-pass-complete status. Project state at entry: 244 requirements, 159 trace links, 16 diagrams, 100 facts in namespace {{hex:50841059}} SE:radiochem-lab-v2.

Findings

Duplicate entities: 71 entities in the SE:radiochem-lab-v2 namespace had global duplicates. All 71 cleaned via deduplication.

Duplicate ARC requirements: Four pairs of architecture decisions contained near-identical text at different detail levels: {{stk:ARC-REQ-001}}/002, {{stk:ARC-REQ-006}}/007, {{stk:ARC-REQ-011}}/012, {{stk:ARC-REQ-017}}/018. The shorter variant in each pair was deleted.

Duplicate diagrams: {{entity:Laboratory Utilities and Building Services}} had two internal diagrams (diagram-1773929239689 and diagram-1773929242626). The newer duplicate was deleted.

Trace rationale: All 159 pre-existing trace links lacked --rationale fields. Links had descriptions but no engineering justification. This is a systemic gap from the first-pass decomposition sessions.

Spray patterns: {{sys:SYS-REQ-009}} (criticality fissile mass limits) traced to 20 SUB requirements — the worst spray in the project. {{sys:SYS-REQ-003}} (effluent batch analysis) and {{sys:SYS-REQ-006}} (airborne alpha detection) each traced to 12. SYS-REQ-009’s breadth is partially justified: criticality safety is genuinely cross-cutting in a nuclear facility handling submarine-origin fissile material. However, links to {{sub:SUB-REQ-041}} (emergency communications) and {{sub:SUB-REQ-094}} (physical security) represent “contributes to” relationships rather than genuine derivations.

Orphaned requirements: 36/244 orphaned at entry. 18 were ARC decisions (expected). 9 SUB and 4 IFC requirements had no upward traceability to system requirements.

SUB→VER coverage: Only 1 of 98 subsystem requirements had a verification trace link. The 59 existing VER entries covered IFC requirements (49 links) and SYS requirements (8 links) but almost entirely omitted subsystem-level verification.

No document sections: All 6 documents lack section structure. Requirements exist in flat lists without organisational grouping.

Lint findings: 1 high — {{entity:Active Drain System}} classified as abstract ({{hex:55D51018}}) despite having physical constraints in {{sub:SUB-REQ-044}}. 2 low findings on classification consistency and language quality (76 reqs without SHALL, all in ARC/VER documents where this is expected).

Corrections

Deleted 4 duplicate ARC requirements: ARC-REQ-002 (duplicate of {{stk:ARC-REQ-001}}), ARC-REQ-007 (duplicate of {{stk:ARC-REQ-006}}), ARC-REQ-012 (duplicate of {{stk:ARC-REQ-011}}), ARC-REQ-018 (duplicate of {{stk:ARC-REQ-017}}).

Deleted 1 duplicate diagram: Laboratory Utilities internal diagram (diagram-1773929242626).

Created 13 trace links with rationale: 9 SYS→SUB links for orphaned subsystem requirements ({{sub:SUB-REQ-066}}, {{sub:SUB-REQ-068}}, {{sub:SUB-REQ-070}}, {{sub:SUB-REQ-071}}, {{sub:SUB-REQ-074}}, {{sub:SUB-REQ-075}}, {{sub:SUB-REQ-076}}, {{sub:SUB-REQ-089}}, {{sub:SUB-REQ-091}}) and 4 SYS→IFC links for orphaned interface requirements ({{ifc:IFC-REQ-051}}, {{ifc:IFC-REQ-052}}, {{ifc:IFC-REQ-053}}, {{ifc:IFC-REQ-054}}).

Created 5 safety-critical VER entries with SUB→VER traces: {{sub:SUB-REQ-032}} ({{entity:Criticality Warning System}} neutron source test), {{sub:SUB-REQ-036}} ({{entity:Safety Interlock and Trip System}} SIL 3 proof test), {{sub:SUB-REQ-037}} (2oo3 voting timing and independence), {{sub:SUB-REQ-010}} ({{entity:Continuous Air Monitor Network}} alpha sensitivity), {{sub:SUB-REQ-038}} ({{entity:Emergency Power System}} UPS and battery autonomy).

Final state: 249 requirements (+5 VER, -4 duplicate ARC), 177 trace links (+18), 15 diagrams (-1 duplicate).

flowchart TB
  n0["Radiochemistry Laboratory"]
  n1["Sample Receipt"]
  n2["Gamma Spectrometry"]
  n3["Alpha Spectrometry"]
  n4["LSC Facility"]
  n5["ICP-MS Suite"]
  n6["Separations Lab"]
  n7["Ventilation"]
  n8["Rad Protection"]
  n9["Effluent Treatment"]
  n10["LIMS"]
  n11["Waste Management"]
  n12["Safety and Emergency"]
  n13["Utilities"]
  n0 --> n1
  n0 --> n2
  n0 --> n3
  n0 --> n4
  n0 --> n5
  n0 --> n6
  n0 --> n7
  n0 --> n8
  n0 --> n9
  n0 --> n10
  n0 --> n11
  n0 --> n12
  n0 --> n13

Residual

159 of 177 trace links still lack --rationale — all pre-existing links from decomposition sessions. Fixing these requires ~159 delete-and-recreate operations, far exceeding a single session budget. The spray pattern on {{sys:SYS-REQ-009}} (20 SUB links) was documented but not pruned; 2-3 links are marginal but the operator should judge whether criticality cross-cutting justifies the breadth. No document sections exist — creating sections would require reorganising 249 requirements across 6 documents. {{entity:Active Drain System}} ontological mismatch remains unfixed.

Next

Validation session should assess whether the project meets engineering quality standards for a nuclear-licensed radiochemistry facility. Key areas for the validator: (1) the 159 trace links without rationale represent a documentation debt that may need a dedicated rationale-backfill session before marking complete, (2) SUB→VER coverage improved from 1% to 6% but remains far below the 50% target — approximately 40 more VER entries needed for safety and measurement subsystems, (3) the SYS-REQ-009 spray should be reviewed for link pruning.