State regulators and oil and gas industry workers are scrambling to assess the damage and mitigate health and environmental impacts of historical flooding on Weld County, one of the most drilled counties in the nation.
"At this point - as access continues to be limited and emergency responders remain focused on lives, property and roadways - we have limited information about specific impacts or particular locations," said Todd Hartman, spokesman for the Colorado Oil and Gas Conservation Commission.
"But as the situation improves, and more information is available, COGCC will be working with state and local authorities, operators and the public to assess risks and, where necessary, provide environmental response and remediation."
Hard-hit Weld County has the highest number of active oil and gas wells in the state at 20,554 - more than a third of the statewide total of 51,228. Yuma County to the east has the third highest number of active wells at 3,343. In addition to the gas and oil operations, officials note other toxic substances of concern.
"Many contaminants, such as raw sewage, as well as potential releases of chemicals from homes, businesses and industry, may be contained in the floodwaters," said Mark Salley, spokesman for the Colorado Department of Public Health and Environment. "People are encouraged to stay out of the water as much as possible . and wash frequently with warm water and soap" if they do come in contact with contaminated water."
A spokesman for the Weld County Department of Public Health and Environment did not return a call requesting comment.
Before the floodwaters even began to recede, citizen activists who monitor drilling operations jumped into action. They have loaded photos of flooded oil and gas wells, chemical storage facilities and wastewater and chemical holding tanks on several different websites, demanding action from state regulators.
A small percentage of the chemicals used in drilling operations and hydraulic fracturing, or fracking, are cancer causing. The situation has prompting concerns about both short- and long-term health risks. The concern is magnified, activists say, by potential spills in heavily populated or agricultural areas.
"Drilling and fracking in floodplains is extremely risky and only amplifies the public health and environmental concerns associated with this dangerous industrial activity," said Gary Wockner of Denver-based Clean Water Action.
"The [health department] and [oil and gas commission] should inspect every well that was flooded, require that the industry clean up every pollution plume, and create new regulations that better protect the public and the environment in and near floodplains."
Hartman said the oil and gas commission is tracking reports and collecting data this week on impacted locations, working closely with industry, local officials and the public. He added the agency is using GIS (geographic information system) mapping to identify oil and gas locations in flooded areas of the South Platte River and its tributaries and forming teams of field inspectors, environmental protection specialists and engineers to focus on areas north and south of the river.
Drilling in the Wattenberg Field of the Denver Basin, which is northeast of Denver, has pushed Colorado oil production to its highest levels since 1957. Fracking has opened up vast new reserves in the area.
Doug Hock, a spokesman for Encana - one of the largest operators in the area - said in the wake of the flood, his company "shut in" 397 of its 1,241 wells in the basin.
"We're using GIS to help prioritize lower-lying facilities that may likely have greater impacts," Hock said in an email. "We're keeping COGCC updated as we move forward with these inspections. We are unaware of any resulting spills at this time."
Another major operator, Anadarko, reports on its website that the company has "shut in" approximately 600 of its wells in the area.
"The majority of our drilling, completions and workover activities in the affected areas of the field have been shut down, and restarting the activities is expected to be significantly delayed due to road and location conditions," the company reported. "We expect to be able to better assess our facilities once the flooding begins to recede and road access improves."
Officials with the Colorado Oil and Gas Association, an industry trade group, did not respond to requests for comment. The state health department's Salley said that the association is coordinating with the state, the U.S. Environmental Protection Agency and the National Response Center to address environmental impacts from the flood.
The oil and gas commission has added a link to its website for anyone to report potential oil and gas or chemical spills related to the flooding.
Power plants in the area have not been impacted by flooding, according to an Xcel Energy spokesman.
"So far we haven't experienced any generation issues due to the flood," said Xcel's Gabriel Romero. The flooding of the St. Vrain River through Platteville, he said, did not damage the company's gas-fired power plant there or a nearby storage facility for 14 tons of spent nuclear fuel from the decommissioned Fort St. Vrain nuclear power plant.
"No issues so far," he said. "We have not escalated our situational alerts thus far, meaning at this point we are not overly concerned with the facility."