Improper CKD Disposal
Op-Ed by Bart Lorang
Is CEMEX Lyons the next Superfund Site?
CEMEX has submitted an application for an additional 15 years of mining at their Dowe Flats Mine near the Town of Lyons. Much of the talk has centered around the cement plant’s enormous emissions, but there are some pretty noteworthy concerns buried in the ground there too.
Cement kiln dust (CKD) is a byproduct of the cement manufacturing process that begins with the extraction of limestone and shale at Dowe Flats. Ultimately, CKD is generated in the cement plant and disposed of adjacent to the plant on the south side of Highway 66. CKD has “been known to precede a number of systemic injuries with particular reference to the respiratory, gastrointestinal, and integumentary systems characterized by fibrosis, emphysema, cough, cancer, inflammation, and liver diseases among workers and host community residents of cement factories”. (Source)
CEMEX CKD Disposal Practices at Lyons Plant Are Unknown
From 1969 to 1999 it is unclear the location of CKD disposal and exactly how much CKD was disposed over the decades. That’s because the Colorado Department of Reclamation, Mining, and Safety (DRMS) didn’t take on CKD disposal regulation for the cement industry until 1999. Since 1999, CKD has been disposed of in C-Pit at the Lyons Quarry (CEMEX’s plant), with a modeled capacity of 600,000 cubic yards over a 20 year time frame.
For reference, a 71-acre Portland Cement site located in Salt Lake City, Utah had about 500,000 cubic yards of CKD deposited as fill material between 1963 and 1983. That activity contaminated soil, air, and groundwater with heavy metals and the site was designated as a Superfund Site. (Source)
Now, Boulder County staff is recommending that we approve CEMEX’s application for an additional 15 years of mining at Dowe Flats, which guarantees 15 more years of plant operations and CKD production and onsite disposal.
Recommendations From Colorado DRMS
According to DRMS, “fresh” CKD should never be placed or allowed to be placed inadvertently, in open flowing water or in areas, such as flood plains, where open flowing water may reach the “fresh” CKD prior to a few weeks of curing. (Source) Did you know that the CEMEX Lyons Plant site is in a Floodway and Floodplain? And that the City of Longmont is downstream?
If that wasn’t scary enough, CKD fugitive dust plumes at CEMEX Lyons are a well chronicled problem. Local residents have been the sole, de facto monitoring mechanism for this for decades. Following up on one such complaint in early 2022, DRMS references the frequent issues at the plant and noted that the CKD disposal pit was not serviced for a number of days, which resulted in the reported dust emissions. The inspector noted, “it appears the operator is not effectively controlling wind erosion of these materials”. (Source)
CKD Disposal Is A Highly Toxic Disaster Waiting To Surface
I’m not sure that I can underscore how dangerous CKD can be to humans, wildlife and the environment, and that there is an unfathomable amount of it generated and then buried at the CEMEX plant site. If not managed properly, CKD can be absorbed into the groundwater, where local residents largely rely on well water, and the groundwater continues downstream to the City of Longmont.
I believe Boulder County and the City of Longmont should deploy local resources to investigate this matter and fully understand the implications to the health and safety of its residents.
In the meantime, I recommend that CEMEX’s application to extend mining at Dowe Flats be REJECTED.
