By Edward McAllister and Selam Gebrekidan
Sept 19 (Reuters) - Political and environmental pressure mounted on energy companies in Colorado on Thursday, as officials tried to assess the damage from oil and gas spills that followed last week’s heavy flooding.
Regulators were tracking 10 oil spills in the north-central portion of the state, where eight people have died and thousands have been displaced, the Colorado Oil and Gas Conservation Commission (COGCC) said in a statement on Thursday.
The COGCC described two spills as “notable”, the rest as “minor”.
The full extent of the damage was still unclear as workers struggled to gain access to some of the worst-hit areas, but leaks were beginning to be reported from well sites ravaged by torrential rains.
Images of tanks that store oil or drilling fluids, unmoored and floating in mud-brown floodwater, have raised concern among local residents, environmentalists and politicians.
The spills in Colorado present a “major public health issue”, Congressman Jared Polis of the second district of Colorado said in a letter to the COGCC. “In light of the serious conditions on the ground, the industry, at a minimum, must disclose all chemicals that may be contaminating soil and groundwater,” he said.
Fertilizer and pesticides and sewage all pose a major threat to the environment after the rains, but much of the worry surrounds the oil and gas production technique known as hydraulic fracturing, or fracking - a newer feature in the state where energy output is on the rise.
Fracking involves pumping millions of gallons of water, chemicals and sand deep underground to fracture shale rock deposits that hold vast amounts of oil and gas. Large amounts of that water returns to the surface and is stored in the kind of tanks that have been seen floating away in the Colorado floods.
Some companies in Colorado, including Encana Corp. and Anadarko Petroleum Corp. do disclose the fracking chemicals used in Weld County wells, according to Frac Focus, a website where energy firms can list substances they use. The drilling fluids contain hydrochloric acid, benzyl chloride and many other chemicals.
A storage tank owned by energy company Anadarko spilled an estimated 125 barrels of oil into the flood-swollen South Platte River in north-central Colorado, the COGCC said on Wednesday.
Separately, Denver-based Kerr-McGee Oil and Gas Onshore company, a unit of Anadarko, reported the spill of an unknown volume of condensate into the South Platte on Tuesday from a 300-barrel-capacity storage tank.
Anadarko deployed absorbent booms to the spills, but oil still escaped.
“In both cases, it appears the oil left the site in floodwaters,” the COGCC said in its statement Thursday.
Noble Energy Inc said it had identified three wells that were leaking natural gas following the floods last week.
Two of the compromised wells were shut on Wednesday, but a third that appeared to be leaking a “limited” amount of gas could not be safely accessed for shutdown, the company said in a statement on Wednesday.
Noble operates more than 8,000 active wells in the DJ Basin in Colorado. Between five and ten percent of those wells have been shut in due to the flood.
Oil and gas was one of myriad problems facing the state as the cleanup continued, regulators said.
“These spills are not an unexpected part of many other sources of contamination associated with the flood,” the COGCC said. “Those include very large volumes (millions of gallons) of raw, municipal sewage and other hazards associated with households, agriculture, business and industry.”