Sometimes conservation work involves work out in the field – or, in this case, the desert.
Last year, staff from the Department of Conservation’s Division of Mine Reclamation (DMR) completed a massive project to assess and remediate abandoned mine features across the Mojave National Preserve. Over the course of this multi-year project, staff worked often dawn-to-dusk, traveling across the Mojave Desert to inspect 65 mine features, making this one of the department’s largest single remediation projects to date.
The primary goal of this remediation work is to collaborate with our partners at the Mojave National Preserve to protect people from abandoned mine hazards in California while preserving mining history and wildlife habitat.
Abandoned mine lands are part of the rich mining history of California, with many abandoned mine features dating back to the Gold Rush. These mines are present in all 58 counties, the majority of which exist on federal land. These sites can be hazards to people, pets, livestock, and wildlife due to accidents or pollutants, but many mines are also habitats for important and threatened California species, especially in arid desert areas where mines can protect wildlife from extreme heat and cold. Since 1997, the Department of Conservation has partnered with federal, state, and local agencies to inventory and assess abandoned mines, then assist with the design and installation of remediation measures to ensure that communities and wildlife living near these features remain safe.
The Mojave National Preserve remediation project encompassed 65 such undertakings over the span of five years, including at many previously untouched sites. The project began in 2020 when staff entered discussions with the National Park Service (NPS). In 2021, staff secured $675,000 in federal grant funding to finance the majority of the project. Staff then contracted with Frontier Environmental Solutions, a remedial contractor who followed State procedures and protocols to complete remediation work. Staff then followed up with site visits to all 65 mines to inspect the remediations, 70% of which occurred at locations that had no previous safeguarding .
Between 2021 and 2025, Conservation staff trekked across the Mojave National Preserve for these remediations and inspections. Travel involved four-wheel driving on rough roads, camping, cross-country hiking, and underground work inside abandoned mining features. Staff traveled in pairs with ample safety equipment, including spare tires for work vehicles, satellite phones, and GPS tracking in order to keep fieldworkers as safe as possible. Most work occurred in cooler seasons from September to April to avoid the scorching summer desert temperatures.
To protect wildlife while preventing human intrusion into these spaces, staff installed fences, wire nets, and most notably, bat gates.
These barred gates, with 5 and ¾ inch openings to allow various species of bats to fly through and keeps the mine safe for them as refuge while preventing human visitors from disturbing their habitats. For many of the Mojave mines, staff also installed an 8- by 10-inch-tall tortoise door to allow access for the Mojave Desert tortoise, which is a threatened species.
In addition to bats and tortoises, mines in the Mojave Natural Preserve are home to many other species, including ringtails, barn owls, and smaller birds (including a nest of baby Say’s phoebes pictured below). Snakes, including rattlesnakes, are also common.
Project lead and Senior Environmental Scientist David Tibor expressed relief that such an extensive project is finally complete. “It was a multi-year project, from remediation scoping … to the environmental compliance MOJA does, to getting a contractor onboard for the construction, and over a year of construction work to build the project fully,” Tibor said. “Our small group has driven and hiked all over the Mojave National Preserve.”
The work doesn’t stop here, however – the team continues to work with the National Parks Service and other state and federal partners to remediate more mines across California, ranging from Death Valley National Park to Whiskeytown National Recreation Area. The team’s efforts continue to protect mining history and habitats while also keeping Californians safe.
The Mojave National Preserve receives hundreds of thousands of visitors per year – including hikers, hunters, campers, and rockhounds, and with most of the 65 remediated sites close to drivable open routes, the new safety remediations helps ensure that passersby remain safe when exploring this beautiful piece of California. Conservation and the National Park Service undertake this work to keep members of the public safe to explore preserved spaces freely while also conserving cultural artifacts and important wildlife habitats. These safety measures ensure the Preserve’s safety for threatened species, future generations of visitors, and an important piece of California’s history.
For more information on the Division of Mine Reclamation and the Abandoned Mine Lands Unit, check out our website.
