Colorado Oil Tank Removal Guide: OPS Rules & Mountain Communities

OPS: An Agency Name That Trips People Up

Colorado regulates both aboveground and underground petroleum storage tanks through the Division of Oil and Public Safety (OPS), part of the Department of Labor and Employment — not the state health or environment department, which is where most homeowners instinctively look first. OPS oversight is codified at 7 CCR 1101-14 and covers permitting, closure procedure, and soil sampling for tank systems statewide.

Permanent closure under OPS rules can happen two ways: removing the tank entirely, or filling it in place with an inert substance. Once you're ready to close a tank system, all liquids and sludge have to be pumped out first, and the closure method you choose determines what happens next.

Why Mountain Communities See More of These Tanks

Heating oil was common in Colorado's mountain communities and in older Denver neighborhoods before natural gas infrastructure reached them. Higher elevations with longer, colder winters made a reliable on-site fuel supply more practical in remote mountain towns than waiting on gas line extensions that, in some cases, still haven't arrived. Older cabins, historic ski-town properties, and rural parcels without nearby gas service are meaningfully more likely to have a buried or above-ground tank than a comparably aged home along the Front Range.

If you're buying an older mountain property with no documented heating history, that's a reasonable trigger for a tank sweep before you assume the furnace has always run on gas or propane.

Permits, Fire Department Notice & the 2019 Rule Changes

A licensed contractor pulls the required OPS permit, typically $75-$200, before draining and cleaning the tank interior. On top of that state permit, local fire departments separately require advance notice of tank closure — a step that's easy to miss if you assume the state permit covers everything. In mountain jurisdictions served by volunteer fire departments rather than full-time staff, that coordination can take longer to schedule than it would in a metro department, so build in extra lead time if you're working toward a closing date or a short mountain construction season.

Colorado's OPS storage tank regulations were amended in 2019, and the update included incentives intended to encourage owners to close out aging systems. Specifics change over time, so confirm current details with your contractor rather than assuming a fixed number applies to your situation.

What Removal Costs in Colorado

A standard underground residential removal runs $1,600-$3,200, covering the OPS permit, excavation, draining and cleaning the tank, hauling, and soil sampling. Front Range properties with easy equipment access tend to land toward the lower end; mountain-town jobs can run higher when a crew has to work around tight lot access, elevation, or a compressed construction season that limits when heavy equipment can even get to the site. If contamination is found, remediation is a separate cost, commonly $12,000-$40,000 depending on how far it has spread.

The Removal Process, Step by Step

1. Confirm the tank. A GPR sweep locates it without digging if there's no documentation.
2. Permit and notify. The contractor pulls the OPS permit and separately notifies the local fire department.
3. Pump and clean. Remaining liquids and sludge are pumped out before excavation begins.
4. Excavate and haul, or fill in place. Full removal or in-place closure with an inert fill, depending on access and owner preference.
5. Soil sampling and closure. Samples confirm clean soil, and the contractor files closure documentation with OPS.

Front Range jobs typically wrap in a day on-site; mountain-town jobs sometimes need a second day if access requires smaller equipment or hand work.