Officials review California Gulch Superfund cleanup, lead-testing program and remaining obligations

At a Feb. 11 work session of the Lake County Board of County Commissioners, U.S. Environmental Protection Agency and Colorado Department of Public Health and Environment officials reviewed the history, current status and remaining obligations for the California Gulch (Leadville) Superfund site and the Lake County Community Health Plan, a long-running, community-based lead-testing and remediation program.

The discussion centered on the site’s mining and smelting legacy, the LCCHP remedy that focuses on reducing children’s lead exposure through testing and education, and the trust funds that currently finance the blood-lead program. “I’m Linda Kiefer. I’m with the U.S. Environmental Protection Agency, and I’ve been the project manager on the site for 16 years,” Kiefer told the commissioners, summarizing the federal role and the site’s long history of cleanup work.

Why it matters: Lake County’s Superfund work spans decades and includes a set of operable units with differing remedies and institutional controls. The LCCHP — selected as the remedy for residential soils in parts of the site — continues to operate as the principal public-health tool to identify elevated blood-lead levels in children, guide behavioral interventions and, in some cases, trigger property remediation paid from settlement funds.

Key facts and program mechanics

- Scope and history: Officials said the California Gulch Superfund site covers roughly 18 square miles and includes the historic mining district, Leadville and parts of the Arkansas River floodplain. Long-term mining and smelting produced slag piles, tailings and widespread soil disturbance. EPA project managers divided the site into operable units and prioritized cleanup and institutional controls by contamination type and land use.

- Remedy and approach: Project managers said the Lake County Community Health Plan was chosen as the residential-soils remedy because it targets exposure pathways that affect children across multiple locations, not only private yards. As one official summarized, “The Lake County Community Health Plan was chosen as the remedy.” The program provides outreach, free blood-lead testing, follow-up consultations and, when an elevated blood lead persists after education and behavior changes, a formal work-group decision that can lead to state-led remediation.

- Investigation and outcomes to date: EPA and state staff said more than 100 residential properties in the designated area have been investigated; 25 properties required soil remediation. Officials said the program’s health-focused, multi-pathway approach has reduced the need for large numbers of full-property remediations by identifying other exposure sources such as interior paint, occupational take-home dust and imported consumer goods.

- Cleanup trigger and screening levels: Officials noted that site-specific factors led to a cleanup trigger used historically in Leadville of 3,500 milligrams per kilogram for lead in soil. That number is higher than typical federal or CDC reference guidance; presenters said the figure was selected after community input and bioavailability studies specific to Leadville soils. Staff also discussed evolving federal guidance: CDC and EPA reference levels and measurement limits have fallen over time (examples discussed in the session included prior reference values of 10 µg/dL, later 5 µg/dL, and measurement considerations down to about 3.3 µg/dL).

- Funding and long-term stewardship: The ASARCO-related settlement trust that funds the clinic-style testing and outreach was reported to hold about $2.7 million. County public-health staff and EPA said the LCCHP typically costs $200,000–$300,000 per year to run; the trust reimburses program costs to the state and county under the trust agreement. Presenters said the trust is segregated and not commingled with other federal funding; if the county or program ceased operations, the trust agreement describes how remaining funds would be allocated.

- Institutional controls, five-year reviews and remaining work: EPA staff said that although nine operable units have been deleted from the National Priorities List, institutional controls and long-term operation-and-maintenance remain. Deleted operable units are still reviewed every five years to confirm protectiveness; some outlying operable units retain controls intended to allow future redevelopment while protecting public health. Project managers identified Strayhorse Gulch and other higher-priority pockets where additional work or monitoring remains.

Quotes and local roles

- “We still look at them every five years and just make sure that the work that we’ve done is still safe,” a state official said of deleted operable units.

- Melanie Granberg, environmental counsel to the county, told commissioners that legal issues such as CERCLA liability and recent state legislative proposals about waste-rock handling could affect county choices on reuse or redevelopment of capped areas. Granberg said she would send commissioners a memo about a Colorado bill under consideration that could change how waste-rock piles are treated under state law.

What the program does — and does not — pay for

Officials clarified that the LCCHP’s pathway to a property remediation generally requires an elevated blood-lead result in a child; the program’s work group then evaluates the case and, when remediation is recommended, the state contracts and performs the remediation. Presenters said that broad, universal yard cleanups without a clinical trigger are not funded under the current trust-driven structure and that full-property remediation can be expensive (staff cited examples where remediations reached several hundred thousand dollars per property when both soil and deteriorated housing conditions required correction).

Public engagement and next steps

Presenters said they welcome community and commissioner input on institutional controls and remedies and offered to meet individually to discuss legal, technical or health questions. County counsel and the state and EPA project managers said they would continue to coordinate on five-year reviews, outreach, and potential legislative or policy developments that could affect waste-rock reuse or liability.

Ending

Commissioners thanked EPA, CDPHE and county counsel for the briefing and said they would follow up on the memo about liability and state legislation. Staff emphasized that the LCCHP remains the county’s primary preventive mechanism for childhood lead exposure in the Superfund area and that funding and stewardship will continue to be monitored as guidance and site conditions evolve.