Former Mine Datacenter Sites in California
At a glance
Decommissioned or active mining land. Mine sites often retain heavy electrical service and water rights from prior operations, and many sit near coal-plant substations now freeing up grid capacity.
Top former mine sites in California
| Site | Type | County | Voltage | Capacity | Queue wait | Score |
|---|---|---|---|---|---|---|
| Mine Site | Former Mine | San Mateo County | — | — | 7.6 yrs | 48.7 |
| Mine Site | Former Mine | San Mateo County | — | — | 7.6 yrs | 48.7 |
| Mine Site | Former Mine | Alameda County | — | — | 7.6 yrs | 48.4 |
| Mine Site | Former Mine | Riverside County | — | — | 7.6 yrs | 48.2 |
| Mine Site | Former Mine | Riverside County | — | — | 7.6 yrs | 48.2 |
| Mine Site | Former Mine | Riverside County | — | — | 7.6 yrs | 48.2 |
| Mine Site | Former Mine | San Francisco County | — | — | 7.6 yrs | 48.2 |
| Mine Site | Former Mine | Sacramento County | — | — | 7.6 yrs | 47.8 |
| Mine Site | Former Mine | Los Angeles County | — | — | 7.6 yrs | 47.7 |
| Mine Site | Former Mine | Los Angeles County | — | — | 7.6 yrs | 47.7 |
| Mine Site | Former Mine | Santa Clara County | — | — | 7.6 yrs | 47.6 |
| Mine Site | Former Mine | San Diego County | — | — | 7.6 yrs | 47.5 |
| Mine Site | Former Mine | San Mateo County | — | — | 7.6 yrs | 47.5 |
| Mine Site | Former Mine | San Diego County | — | — | 7.6 yrs | 47.5 |
| Mine Site | Former Mine | San Diego County | — | — | 7.6 yrs | 47.3 |
| Mine Site | Former Mine | Fresno County | — | — | 7.6 yrs | 47.3 |
| Mine Site | Former Mine | Fresno County | — | — | 7.6 yrs | 47.3 |
| Mine Site | Former Mine | Alameda County | — | — | 7.6 yrs | 47.3 |
| Mine Site | Former Mine | Alameda County | — | — | 7.6 yrs | 47.2 |
| Mine Site | Former Mine | San Diego County | — | — | 7.6 yrs | 47.2 |
| Mine Site | Former Mine | Riverside County | — | — | 7.6 yrs | 47.2 |
| Mine Site | Former Mine | Alameda County | — | — | 7.6 yrs | 47.1 |
| Mine Site | Former Mine | Alameda County | — | — | 7.6 yrs | 47.0 |
| Mine Site | Former Mine | Los Angeles County | — | — | 7.6 yrs | 47.0 |
| Mine Site | Former Mine | San Mateo County | — | — | 7.6 yrs | 46.7 |
How does California compare with other states for former mine sites?
With 451 sites, California ranks 12th of the 50 states that have any former mine candidate sites. Kentucky leads with 5,049. Nationally, former mine sites average 49.7/100 DC Readiness, below the 53.0 average across all site types. Across every site type, California averages 45.4, the 52nd-highest of 52 states, and its candidate sites face an average interconnection-queue wait of 7.6 years.
Where are the highest-scoring former mine sites in California?
The top 25 range from 48.7 to 46.7 on the 0–100 DC Readiness Score. They are concentrated in Alameda County (5), San Mateo County (4), Riverside County (4) and San Diego County (4). By grid region, 22 are in CAISO and 3 are in WECC.
County pages: Alameda County · San Mateo County · Riverside County · San Diego County
What power, fiber and flood exposure do these former mine sites have?
Their counties have a median of 13 fixed fiber broadband providers in FCC data. The median distance to the nearest internet exchange facility is 4 km. The median interconnection-queue wait in their markets is 7.6 years. None of the 3 with a mapped FEMA flood zone sits in a high-risk (A or V) zone. 7 lie within 25 km of a binding transmission constraint.
Frequently asked questions
How many former mine datacenter sites are in California?
GridCensus catalogs 451 former mine datacenter candidate sites in California, 2% of the national total for this type (12th of 50 states).
What is a former mine datacenter site?
Decommissioned or active mining land. Mine sites often retain heavy electrical service and water rights from prior operations, and many sit near coal-plant substations now freeing up grid capacity.
What is the best former mine datacenter site in California?
By DC Readiness Score, Mine Site in San Mateo County ranks first at 48.7/100, followed by Mine Site in San Mateo County at 48.7.
Which California counties have the best former mine sites?
The top 25 former mine sites in California are concentrated in Alameda County (5), San Mateo County (4), Riverside County (4) and San Diego County (4).
How does California score for datacenters overall?
All 8,490 scored sites in California average 45.4/100 DC Readiness, the 52nd-highest of 52 states, against a national average of 53.0.
More on former mine sites and California
- All datacenter sites in California· 8,490 sites
- Former Mine datacenter sites nationwide· 26,205 sites
- Federal Excess sites in California· 3,212 sites
- Industrial sites in California· 2,201 sites
- Substation-Adjacent sites in California· 1,573 sites
- Greenfield sites in California· 941 sites
- Brownfield sites in California· 103 sites
- Military BRAC sites in California· 9 sites
Former Mine sites in other states
- Former Mine sites in Kentucky· 5,049 sites
- Former Mine sites in Pennsylvania· 3,356 sites
- Former Mine sites in West Virginia· 2,495 sites
- Former Mine sites in Virginia· 1,614 sites
- Former Mine sites in Alabama· 1,069 sites
- Former Mine sites in Texas· 935 sites
- Former Mine sites in Ohio· 925 sites
- Former Mine sites in Tennessee· 661 sites
Dataset updated . Screening estimates derived from public data sources.
About this data
Source: GridCensus composite of HIFLD transmission and substation data, EIA, FEMA National Risk Index, FCC broadband data, PeeringDB and ISO interconnection queues, as published November 13, 2026 — GridCensus refreshes it monthly. See the methodology for how records are matched, cleaned and scored.
Cite as: GridCensus, “Former Mine datacenter sites in California”, https://gridcensus.com/site-types/mine/california (data as of November 13, 2026).
Go deeper than the public screen
Every site and score for Former Mine sites in California is free to browse. Pro adds Watchtower on 25 sites, alerts when new candidate sites, datacenters or interconnection-queue requests appear in your markets, score and capacity history, and CSV export. Enterprise adds team seats, weekly data files for all 147,272 sites, the REST API and an MCP server for AI tools.