From The Leadville Herald-Democrat (Sean Summers):
Following more than a year of back-and-forth with state regulators, the Leadville Sanitation District has been issued a new wastewater discharge permit that will allow for the same amount of mercury to be present in treated water released into California Gulch.
The new permit, issued by the Colorado Department of Health and Environment (CDPHE), came after outside evaluations and public comments to the state agency called attention to Leadville Sanitation District’s (LSD) inability to meet proposed lower mercury limits without substantial upgrades.
The previous permit limited acceptable mercury levels in treated water to 0.077 micrograms per liter. Though CDPHE was going to require a lower limit of 0.044 micrograms per liter in the new permit, the limit will remain the same under the recently implemented five-year discharge permit.
While the new permit maintains the same limits for mercury levels, it requires the sanitation district to monitor for a number of contaminants not previously recorded, including uranium and radium, among others.
The permit, citing a 1989 report regarding the release of gasoline from underground storage tanks, also calls for new monitoring of benzene, toluene, ethylbenzene and xylene given the potential for groundwater contamination from the Tabor Grand Hotel service site.
The permit went into effect on Jan. 1, and requires regular reporting of contaminant levels to CDPHE.
LSD has had issues meeting the 0.077 microgram-per-liter mercury limit in the past. The district was found to be out of compliance with state-determined mercury limits in 2017, prompting evaluations of the district’s collection system.
As the organization responsible for receiving, treating and releasing all of Lake County’s wastewater, LSD has since been evaluating the sources of entry for contaminants into the county’s wastewater system.
While the district has not been able to pinpoint the exact entry point for mercury and other contaminants, evaluations of the district’s aging collection system, made up of pipes and drains throughout Leadville, suggest that the intake system has leaks which may allow for contaminant infiltration and leakage.
After recording a lower-than-expected amount of incoming sewage based on the number of residences and businesses served in the sanitation district, CDPHE is requiring LSD address the issue under the new permit. In its explanation of the new requirement, CDPHE says the low input may be a result of sewage leaking from the collection system before reaching the treatment facility.
The new permit requires LSD to meet acceptable mercury limits stipulated in the 2021 permit by September 2023. The district is required to submit a report that identifies sources of cadmium, zinc, benzene, toluene, ethylbenzene and xylene by Sept. 30 of this year.