Okay, let's break down the options for dealing with those conductors in the duct bank to be demolished, keeping safety and best practices in mind.

Understanding the Situation Service Continuity

A critical piece is that the existing electrical service must remain feeding a building.

Duct Bank Demolition

The duct bank itself is being removed as part of the building demolition.

Circuits No Longer Used

The circuits within the duct bank are being decommissioned entirely.

Options and Considerations1. Electrical Contractor Removes Conductors (Best Practice)



Pros



Safety

This is the safest and most controlled option. A qualified electrician is responsible for disconnecting, testing for any residual voltage, and physically removing the conductors. This eliminates any potential risk of accidental energization or shock during the demolition process.

Liability

The electrical contractor assumes responsibility for proper disconnection and removal, reducing the liability for the demolition contractor or other parties.

Code Compliance

Ensures compliance with electrical codes regarding removal of abandoned conductors.

Proper Disposal/Recycling

The electrical contractor can ensure the conductors are properly disposed of or recycled, which is important for environmental responsibility.

Cons



Cost

This will likely be the most expensive option due to the labor involved.

Coordination

Requires careful coordination with the demolition schedule.2.

Electrical Contractor Disconnects and Safes Off, Others Remove Conductors (Less Desirable)



Pros



Cost Savings (Potentially)

Might appear cheaper if the demolition contractor handles the physical removal.

Cons



Safety Risk

The biggest concern. Demolition crews are not generally trained or qualified to handle electrical conductors, even if they are supposedly disconnected. There's a risk of misidentification, accidental cutting through potentially live wires, or other hazards.

Liability

Even if you disconnect and "safe off," you could still be held liable if someone gets injured due to improper handling of the conductors after you release control of them. It's difficult to prove that the demolition crew acted negligently.

Compliance Concerns

May not meet code requirements, particularly regarding who is qualified to perform electrical work.

Communication Breakdown

High potential for miscommunication between the electrical contractor and the demolition crew regarding the exact circuits that are disconnected.3.

Abandonment in Place (Potentially Viable, Requires Careful Evaluation)



Pros



Cost Savings

The cheapest option, as it avoids the labor of removing the conductors.

Cons



Code Compliance



This is the biggest hurdle. The NEC (National Electrical Code) has specific rules about abandoning conductors in place. You would need to carefully review these and ensure your situation meets the requirements. Typically, abandoned conductors must be disconnected at both ends and made inaccessible. The requirement is to make sure no one is working on them in the future. Future Issues

Abandoned conductors could potentially cause problems in the future if the duct bank is ever disturbed.

AHJ Approval

You would absolutely need to get approval from the local Authority Having Jurisdiction (AHJ) before abandoning conductors. The AHJ may have specific requirements or objections to abandonment.

Requirements to Consider for Abandonment (Assuming AHJ Approval)



Thorough Disconnection

Completely disconnect conductors at both ends.

Insulation

Make sure the conductors are properly insulated.

Marking

Clearly mark the conductors as "Abandoned" or "Not in Service."

Accessibility

The conductors must be considered inaccessible, which in most cases requires completely filling the duct bank.

Practical RecommendationOption 1 (Electrical Contractor Removes Conductors) is the most practical and responsible course of action. While it may be the most expensive upfront, the safety and liability benefits far outweigh the cost.

Here's a breakdown of the steps I would take


Site Survey and Planning

Conduct a thorough site survey to identify all affected circuits, their termination points, and the physical layout of the duct bank.2.

Coordination

Coordinate closely with the demolition contractor to understand the demolition schedule and ensure that the electrical work is completed before the duct bank is disturbed.3.

Disconnect and Lockout/Tagout

Disconnect the conductors at both ends, following proper lockout/tagout procedures.4.

Testing

Verify that the conductors are de-energized using a reliable voltage tester.5.

Removal

Carefully pull the conductors from the duct bank, taking precautions to avoid damage to the remaining service cables.6.

Disposal/Recycling

Properly dispose of or recycle the conductors.7.

Documentation

Document the work performed, including photographs and a detailed description of the circuits removed.

If you are absolutely considering Abandonment in Place


Consult with AHJ

Have a discussion with the AHJ before doing anything else. Get their feedback and any specific requirements they may have.2.

Detailed Code Review

Thoroughly review the NEC and any local amendments related to abandoned conductors.3.

Careful Disconnection and Marking

Disconnect the conductors at both ends, insulate them, and clearly mark them as "Abandoned" or "Not in Service."4.

Inaccessibility

If needed backfill the duct bank.5.

Documentation

Document everything, including photos, code references, and AHJ approval.

Why I Strongly Disadvise Option 2 (Others Remove)

The risk of safety incidents and potential liability is simply too high. You have no control over how the demolition crew handles the conductors, and any mistake could have serious consequences.

In Summary

Prioritize safety and code compliance. Removal by the electrical contractor is the most controlled, safest, and defensible option. Abandonment in place is possible* but requires very careful planning, AHJ approval, and meticulous execution. Avoid having the demolition crew handle the conductors after disconnection, as it creates unacceptable risks. Flag for review