California · Area of Critical Environmental Concern
Mountain Pass Dinosaur Trackway
BLM found a historic value here, and its plan calls for special management. BLM's records place at least 24 active mining claims inside the line today. It covers 596 acres and was designated September 14, 2016, in the CDCA Plan, as amended by DRECP. In the plan's name, CDCA stands for California Desert Conservation Area and DRECP for Desert Renewable Energy Conservation Plan.
One of the 1,120 places the Bureau of Land Management has designated an Area of Critical Environmental Concern. This page shows its line, what BLM found there and what sits inside it.
The line
Who holds the claims
At least 24 claims sit inside this line: 24 active, 24 with a holder BLM names. BLM lists 24 as Active.
- SECURE NATURAL RESOURCES LLC24claims
BLM's mining rules list designated ACECs among the places where mining that disturbs the surface beyond casual use needs a plan of operations BLM approves. Exploration of five acres or less can go ahead on a notice instead.
The nearest areas
- IvanpahCalifornia · 86,428 acres · at least 703 active mining claims and 637 more BLM lists as Filed, 42 rights of way, a grazing allotment covering part of it7miles
- Crescent TownsiteNevada · 436 acres · nothing placed inside19miles
- Halloran WashCalifornia · 1,744 acres · at least 23 mining claims BLM lists as Filed, 3 rights of way19miles
- IvanpahNevada · 31,857 acres · at least 15 active mining claims and 4 more BLM lists as Filed, 9 rights of way20miles
- Mesquite LakeCalifornia · 6,761 acres · at least 20 mining claims BLM lists as Filed, a grazing allotment covering part of it20miles
Next to it
Ivanpah Area of Critical Environmental Concern touches the line.
More from BLM's California office
Every area BLM's California office holdsThe proposed rule
A proposed rule, RIN 1004-AF53, would change how BLM drafts every land use plan, and how it designates ACECs like Mountain Pass Dinosaur Trackway. The comment window hasn't opened: the proposed rule wasn't in the Federal Register at our last check. The Watch sends one email the day it prints.
The rule's abstract
The purpose of this rulemaking is to establish in regulations an updated process for the approval of the development, revision, amendment, and maintenance of land use plans, as provided for by the Federal Land Policy and Management Act of 1976, for public lands administered by the Bureau of Land Management (BLM). Additionally, this rulemaking will provide clarification of the process the BLM uses for designating Areas of Critical Environmental Concern.Unified Agenda entry for RIN 1004-AF53, Publication ID 2026, reginfo.gov (OMB OIRA), read Oct 18, 2026