Last reviewed: 13 November 2026

Telecommunications sites often rely on standby diesel generators in small compounds, rooftops or remote cabinets. A fuel leak can go unnoticed between maintenance visits and reach the surrounding ground or drainage before anyone arrives. The best response is early detection, sound storage and clear instructions for the engineer who discovers it.

Inspect the whole fuel system

Check bulk tanks, day tanks, filling points, supply and return lines, filters and flexible connectors. Review bund condition, liquid detection alarms, security and the route of any overflow. A secondary containment system must be compatible with the fuel, sized appropriately and kept clear of accumulated rainwater where required.

Do not assume every backup-generator installation has the same legal requirements. Tank arrangements, oil type, capacity, location and jurisdiction can change the rules; assess the installation against the applicable oil-storage and fire guidance.

Keep maintenance leaks contained

A compatible drip trays may help with routine servicing drips, while oil-only absorbents or spill kits can assist trained engineers with a small, identified diesel or lubricant leak. Prevent fuel from entering rooftop outlets, surface-water gullies or cable ducts.

If the leak affects electrical equipment, isolation and access control take priority over absorbent deployment. Larger releases or contamination of ground or water may require a specialist contractor and prompt notification. Used absorbents are potentially contaminated waste, not ordinary litter.

Prepare for unattended periods

  • Record inspections, fuel deliveries and alarm tests.
  • Keep the site drain and bund plans available to visiting contractors.
  • Provide suitable response materials where engineers can reach them safely.
  • Set clear escalation arrangements for after-hours alarms.
  • Investigate repeated losses rather than topping up fuel indefinitely.

The Environment Agency pollution-prevention guidance for businesses in England offers an England-specific starting point for pollution prevention. Site operators should verify the applicable national and local rules.