DURANGO — Environmental Protection Agency officials facing sad, scared and angry residents whose river is being poisoned after botched federal work on an old mine apologized Friday, calling it a tragic disaster and revealing some of the contaminants in the water.

The soupy yellow-orange Animas River contains arsenic, lead, cadmium, aluminum and copper — among other potentially toxic heavy metals — “at varying levels,” the officials said in a packed public meeting.

But exactly how much remained uncertain Friday night, frustrating local authorities scrambling to protect public health and line up sufficient alternative water sources.

An acidic, yellowish discharge still was leaking out of the Gold King Mine portal, about 60 miles north of Durango (population 17,000), at an estimated rate of about 1,200 gallons a minute, state and federal officials said. EPA crews at the mine were trying to create a large hole to catch the contaminant-laced wastewater and try to clean it before it reaches streams and rivers.

EPA regional chief Shaun McGrath told residents the spill may be worse than a one-time belch from the mine with long-term downriver impacts leading to possible closures next spring and after as river currents re-churn deposited heavy metal contaminants.

“If you are seeing signs of animals that are suffering or dying, let us know,” McGrath told residents, urging cooperation and pledging support from keeping officials better informed to lining up safe water supplies. Domestic wells along the river will be tested for contamination, EPA officials said, and irrigation ditches that weren’t closed in time and took in contaminants would be addressed.

A yellow-orange plume from an initial surge estimated at 1 million gallons — still visible in Durango on Friday afternoon — was moving toward New Mexico and Utah. Federal and state agencies in those areas were mobilizing to track downriver impacts along the San Juan River and other waterways in the Colorado River Basin.

EPA workers triggered the spill Wednesday morning while they were investigating a worsening acid discharge from Gold King and three other mines in the mountains north of Silverton.

They were using a heavy digging machine. EPA’s on-scene coordinator, Hays Griswold, said “We were investigating where we could put in a pipe” to try to drain rising waters inside the mine. The EPA crew had stopped working momentarily.

“We had found the hard rock I wanted to find overhead,” Griswold said. “All of a sudden, there was a little spurt from the top.”

Then a flood of the built-up acid discharge blew through lose dirt, the only barrier between the collapsing mine portal and waterways. The bright orange wave tore down into Cement Creek, which flows into the Animas River.

EPA chiefs flew in Friday and acknowledged an inappropriate initial response Wednesday in which they downplayed the severity and failed to anticipate the downstream impacts.

Durango identifies itself as the “River City,” and residents’ lives revolve around fishing, swimming, tubing and entertaining tourists along the Animas River.

Most longtime residents know too well the problem of old mines that leak heavy metals into headwaters — an issue around Colorado and the western United States — but never expected a ruinous onslaught like this.

Holly Jobson, 62, walking at noon along banks where yellow sediment was glomming onto rocks, said Silverton ought to push for a proper federal cleanup around mines. Silverton officials in the past have resisted, fearing the stigma of a federal Superfund cleanup designation and the impact on tourism.

“I don’t know why we can’t get the best possible cleanup,” Jobson said. “This is awful. All that wildlife along the river. It may kill everything. And the water. Rivers are wonderful. And to have this happen?”

Some wept openly after waking up Friday and seeing the orange-yellow currents. From store clerks on Main Street to county officials at a basement command post, they were asking one overriding question: “What is in the water?”

That question still wasn’t fully answered Friday evening as the EPA’s top officials returned to Denver. They said they need more lab test results to know levels of contaminants. They said they must sample more water and analyze the data but that now they will use a local lab to speed their process.

The river remains closed, La Plata County Sheriff Sean Smith said. County health officials said that, based on the limited information, health risks remain high.

The discharge still flowing out of the mine Friday evening was darker in color, and Dave Ostrander, the EPA’s regional director of emergency preparedness assessment and response, said the initial “slug” moved beyond Silverton.

“We are very sorry for what happened. This is a huge tragedy,” Ostrander told residents. “It’s hard being on the other side of this. Typically we respond to emergencies; we don’t cause them. … It’s something we sincerely regret.”

Ostrander acknowledged that EPA public records on the Gold King Mine site were not accessible to the public and promised to change that.

U.S. Sen. Michael Bennet issued a statement saying he called EPA officials in Washington, D.C., urging attention to the spill and that there must be a follow-up look at what happened.

U.S. Rep. Scott Tipton, who represents the district, said the EPA must be held accountable and pay restitution and damages.

“If a mining operator or other private business caused the spill to occur, the EPA would be all over them,” Tipton said in a statement. “The EPA admits fault and, as such, must be accountable and held to the same standard.”

State Sen. Ellen Roberts, who lives near Durango and sat by the Animas for six hours Thursday as the yellow-orange plume was approaching, said Friday this was “an EPA-caused Love Canal” where the EPA worsened the harm by not warning locals until it was too late and then leaving the community “disarmed” in responding.

“It is an improvement to be hearing the words ‘tragedy,’ ‘disaster,’ and that they caused it and that they are sorry,” Roberts said.

“Those are important words for us to hear. But they don’t change the fact that our river is still orange and that there are question marks about its future — which is intertwined with our future,” she said.

“Now we need action.”

Bruce Finley: 303-954-1700, bfinley@denverpost.com or twitter.com/finleybruce