State officials delay water testing near Lowry superfund site, citing pandemic concerns


AURORA | Citing COVID-19 health concerns, the state health department has postponed a plan to test residential water wells in Gun Club Estates for possible contamination from the Lowry Landfill Superfund Site. 

The Colorado Department of Public Health and Environment had recommended testing wells supplying residents with drinking water in the east Aurora neighborhood near the intersection of South Gun Club Road and East Mississippi Avenue. Spokesperson Jeannine Natterman said the work would involve meeting in-person with property owners, but that “hasn’t been possible” since the new coronavirus pandemic swept into the region in March. 

The testing would likely look for 1,4 dioxane — a cancer-causing chemical if ingested in high concentrations — and other industrial waste dumped decades ago at the Lowry Landfill, which is about three miles away. Natterman said the health department hasn’t mapped a testing plan yet. Gun Club Estates is also close to two landfill sites that could contribute to underground pollution, according to the health department. 

Unlike Murphy Creek and the Waterstone development, many Gun Club Estates residents don’t draw from city water systems because homes were built before Aurora annexed the land. About 50 active, residential water wells supply water to about 140 people, according to CDPHE. 

Water wells are also common in Thunderbird Estates to the north, but CDPHE determined that area isn’t at risk and doesn’t warrant testing. 

There’s no evidence that wells in Gun Club Estates are contaminated either. But comprehensive testing is a key goal for residents who say more information is needed to conclude that the decades-old Superfund site isn’t still leaking waste into groundwater, residents’ wells and the surface of shallow Murphy Creek.  

Dietrick McGinnis, an environmental engineer hired by the site citizen’s oversight group, told Aurora’s city council last week it should be a “knee jerk” reaction to test wells in Gun Club Estates and possibly supply residents with bottled water.

The neighborhood lies at the tail end of a prominent “plume” of toxic waste extending — on the surface and underground — miles north from the Superfund site. 

In 2017, an EPA investigation couldn’t conclude whether groundwater up to 350 feet deep was protected from toxic waste leaking in. Groundwater typically flows north from the Lowry Landfill site toward residents in Murphy Creek and Gun Club Estates. Residents’ wells usually draw from the lower Denver aquifer at an average depth of 785 feet. 

“Nothing is impossible,” said Bonnie Rader, who leads the citizens oversight group. “We are hoping, of course, that they are too deep.”

While McGinnis argues that residential wells could be sullied by waste leaching into deep aquifers, CDPHE engineers said in a recent investigation that’s probably unlikely, but testing would help assuage residents’ concerns. 

A parallel team of engineers also disagrees with McGinnis. The 500-acre Superfund site, which has long been covered with earth, is overseen by the City and County of Denver and Waste Management on behalf of dozens of companies that legally dumped liquid and solid waste, including Hewlett Packard and Conoco Inc. 

Paul Rosaco, an engineer hired by Denver and Waste Management, said last week the plume is actually shrinking and not continuing to sully groundwater sources. 

Policy on the Superfund site has long been hammered out in a thicket of warring opinions. A state health department investigation in 2015 estimated that 425 million gallons of contaminated water had leaked from the site in the groundwater plume, according to data from about a decade earlier. In its 2017 review, the EPA couldn’t conclude whether the site management as a whole was adequately protecting the public. 

In that review, EPA staffers also conducted interviews with residents. All of them were “concerned about groundwater contamination and the use of private residential wells,” the paper reads. 

Rosaco and McGinnis also don’t agree on whether golfers or residents wading into Murphy Creek are at risk. 

McGinnis said last week he wouldn’t want his children near the creek; Roscao cited an EPA conclusion that, even if a golfer on the Murphy Creek golf course was deep in the water for an hour at a time and even drank some of the water, there would be no increased risk of developing cancer. 

Although CDPHE has postponed the well testing, a deep EPA investigation into the Lowry Landfill site is due in the coming months.