A mine maintenance contractor in western Australia's analog in Nevada - a US copper mine - sent a three-person crew to perform routine electrical maintenance on the processing plant's motor control centers. The COI was on file and had been marked compliant. Six weeks later, an arc flash incident severely burned two of the three workers. Workers' compensation covered the workers. But investigation revealed the contractor had changed carriers at their last renewal and the new WC policy contained a class code exclusion for electrical maintenance work performed in mining environments. The new carrier denied the WC claim, citing the exclusion.
The mine operator ended up exposed for the workers' medical costs as a statutory employer in the applicable state - a liability that materialized because the renewal COI was marked compliant based on the presence of a WC line, not a review of the new policy's class code structure.
This checklist is built to catch that kind of gap.
How to Use This Checklist
Work through every item for every contractor, at initial engagement and at every policy renewal. Do not shortcut sections based on contractor familiarity or low perceived risk - the arc flash example above involved a routine maintenance contractor on a low-priority task.
For each section, mark items as: Pass / Fail / Needs Documentation. Fail items require formal deficiency notices before the contractor accesses the site. "Needs Documentation" items require follow-up with the contractor's broker before making a compliance determination.
Section 1: Basic COI Elements
- Named insured on COI exactly matches the legal entity in the access agreement or MSA
- If contractor operates under multiple entities (holding company, operating subsidiary), the contracting entity is the insured entity
- Certificate holder lists the mine operator's correct legal entity name
- All policies are currently in force (effective dates before today, expiration dates after the planned work period)
- Insurer names are identifiable and admitted carriers in the applicable state
- No unusual qualifications or restrictions in the description of operations box without follow-up verification
Section 2: General Liability
- Per-occurrence limit meets the access agreement/MSA requirement (typically $2M-$5M for mining)
- General aggregate meets the access agreement/MSA requirement (typically $4M-$10M)
- Products/completed operations aggregate is separately stated and meets requirements
- No residential exclusion (generally not an issue in mining, but verify for any contractor working in or near residential areas)
- XCU confirmation: For excavation, drilling, and blasting contractors, confirm the GL policy does NOT contain explosion, collapse, and underground hazard exclusions - or that separate coverage is in place
- If the GL contains an absolute pollution exclusion, standalone pollution liability is verified separately (see Section 5)
- For contractors with design-assist responsibilities, confirm professional services exclusion is addressed by a separate professional liability policy
Section 3: Workers' Compensation and Employers' Liability
- WC policy covers the state(s) where the mine is located (not just the contractor's home state)
- WC policy lists the correct NCCI or state-specific class codes for the work being performed at the mine
- For underground contractors, confirm the WC policy covers underground operations (some policies contain underground mining exclusions)
- Employers' liability limits: $1M/$1M/$1M minimum (higher for underground operations)
- Waiver of subrogation endorsement is present on the WC policy
- If the contractor uses independent owner-operators or subcontracted labor, confirm WC coverage extends to those workers or that separate coverage exists
Workers' compensation in mining is among the highest-risk classifications. WC policy review at the class code level - not just the presence of a WC line - is essential.
Section 4: Commercial Auto
- Auto liability CSL meets the access agreement/MSA requirement (typically $1M-$2M for mining)
- Hired auto coverage included if contractor uses rented vehicles or contracted drivers
- Non-owned auto included if contractor employees use personal vehicles for work travel to site
- For transport and haulage contractors: confirm coverage extends to the type of cargo being transported (ore concentrate, reagents, fuels may require separate cargo coverage)
- For hazardous materials transport: confirm auto policy covers the specific hazard class of materials being transported; pollution endorsement may be required
Section 5: Pollution Liability
Pollution liability is the most critical and most frequently deficient coverage in mining contractor COIs. Review this section with particular care.
- Standalone contractor's pollution liability (CPL) policy is present - OR - GL policy has been verified not to contain an absolute pollution exclusion for the contractor's scope of work
- CPL per-occurrence limit meets access agreement/MSA requirement (typically $2M-$5M minimum)
- CPL covers cleanup costs, not just third-party bodily injury and property damage (many CPL policies cover all three; some limit coverage to certain types)
- CPL does not contain an exclusion for mining operations or the specific contaminants at the mine site
- CPL effective dates are current and align with the contract period
- CPL retroactive date does not exclude pre-existing conditions relevant to the contractor's scope
- For contractors transporting or handling processing chemicals (cyanide, acids, reagents): confirm CPL covers sudden and accidental chemical releases AND gradual releases
| CPL Coverage Element | What to Check |
|---|---|
| Per-occurrence limit | Minimum $2M; $5M for high-hazard chemical handlers |
| Coverage trigger | Confirm both sudden/accidental AND gradual pollution events |
| Mining operations exclusion | Must be absent - some CPL policies restrict mining |
| Retroactive date | Must precede contract start date |
| Named insured | Must match contracting entity exactly |
Section 6: Umbrella/Excess Liability
- Umbrella/excess limit meets access agreement/MSA requirement (typically $5M-$25M for mining)
- Umbrella follows form over general liability - not just over GL; also over WC employers' liability and auto
- Umbrella does not contain independent exclusions that contradict the underlying GL coverage (particularly for pollution, explosion, underground hazard)
- If GL contains a pollution exclusion and CPL is separate, confirm the umbrella sits above the CPL as well as the GL
The umbrella-follows-form issue is critical in mining. If the GL contains an XCU exclusion and the umbrella follows form, the umbrella also excludes XCU - meaning there is no excess coverage for an explosion or underground hazard claim, regardless of the umbrella limit.
Section 7: Endorsements
- Additional insured endorsement is present on GL (confirm form; not just checkbox)
- AI endorsement names the mine operator's correct legal entity
- If the access agreement requires AI status for the landowner or mine owner in addition to the operator, all required entities are named
- WOS is present on GL
- WOS is present on WC employers' liability line
- WOS is present on auto if required
- Primary and noncontributory endorsement is present if required by the access agreement
- Notice of cancellation provision matches the access agreement requirement (typically 30 days)
Handling Specialty Contractors with Non-Standard Coverage
Some mining contractors - particularly small specialty firms or international contractors - carry non-standard policies that don't map cleanly to the ACORD 25 format. Common situations:
Lloyd's or surplus lines coverage: Legitimate but requires additional review of the actual policy terms; Lloyd's certificates look different from ACORD 25 certificates.
Captive insurance programs: Some large mining contractors self-insure through captive arrangements. Verify the captive's capitalization and confirm it meets the financial strength requirements in the access agreement.
International policies with US endorsements: Contractors based outside the US may carry primary coverage from their home country's insurer with US-admitted endorsements. Confirm US coverage applies to work performed at US mine sites.
For any non-standard coverage situation, obtain the actual policy documents (not just the COI) and review them against the access agreement requirements before granting access.
Bramble reads access agreements, MSAs, and other mining contract documents to extract insurance requirements, then compares them against the incoming COI - including mining-specific coverages like pollution liability and blasting coverage. Non-standard or deficient COIs are flagged for risk manager review before the contractor accesses the site. See how Bramble works for mining risk managers.