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Black Diamond Mines
Highlighting the History of the Land * Contra Costa County

Overview
Black Diamond Mines Regional Preserve is an area rich with history and natural beauty. Once home to several mining towns, this area was later used as ranchland until a proposal to strip mine the land for sand galvanized local residents and organizations to permanently protect this area. The Nortonville Loop hike wanders through historic mining areas along the western end of the preserve, and the second hike traces the eastern boundary of the park along an area that may soon become a massive sprawl-style development.

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Basics

Location:	Black Diamond Mines Regional Preserve, East Bay Regional Park District
Phone:	925.757.2620
Hike Length & Time:	5.5 miles, 3-5 hours
Elevation Gain:	500-1000 ft
Rating:	Moderate
Park Hours:	8 am - dusk, year-round
Other Information:	(All not allowed in mines.)

· Map

· Getting There

· A Brief History of the Area

· The Nortonville Loop

· The Sprawlside Loop

Map

Getting There
Nortonville Loop: Take Highway 24 from Highway 580 until you get to Highway 680. Take 680 north to Highway 242, then take 242 north to Highway 4 east. You can also take Highway 80 east to its junction with Highway 4. In either of these cases, take Highway 4 east to the Somersville Road exit and take Somersville Road south for 2.7 miles to the park entry station, then go an additional 1.2 miles to the parking lot at the end of Somersville Road.

Sprawlside Loop: Follow the directions above for Black Diamond Mines, but just before you hit the preserve, go left off of Somersville Road onto James Donlon Boulevard. Go right on Lone Tree Way, then right on Golf Course Road, then right on Frederickson Lane. Where Frederickson Lane makes a sharp right turn, pull off the road and park.

A Brief History of the Area
The first people inhabited this area perhaps 10,000 years ago. When Spanish explorers came into what is now eastern Contra Costa County in 1772, several tribes belonging to the Bay Miwok cultural and linguistic group inhabited the area. Nearby Mt. Diablo was an important spiritual center for the area's residents, who inhabited small villages and lived in harmony with the abundant plant and animal life that then filled this area. By the end of the 1790s, the native people were either forced out of the area or driven to the Spanish mission in San Jose, where they were decimated by European diseases and forced labor.

With Mexico's independence from Spain in 1821, this area became part of Mexico until 1848, when the United States acquired California as part of the treaty ending the Mexican-American War. American ranchers moved into this area after the Gold Rush of 1849, and the first coal discoveries were made around 1855.

The coal, also known as "black diamond," that gives this area its name was formed by the accumulation of bits of dead plants that grew here millions of years ago. Under heat and pressure the partially decayed plant matter transformed over millions of years into a low-grade coal called "lignite."

The lignite coal beds in this area were the largest known and most extensively mined coal deposits in California. From the 1860s to the early 1900s, twelve mines produced approximately four million tons of coal valued between $15 and $20 million. This coal fueled the development of the rapidly expanding urban and industrial centers of the San Francisco Bay Area at the end of the 19th Century. The miners in this area lived in five towns: Nortonville, Somersville, Stewartsville, Judsonville and West Hartley's. Nortonville was the largest of these towns, boasting a population of 900 in the 1870s.

After coal mining ended in the early 1900s, white sands used for making glass were mined from two deposits in this area from 1920 to 1949. In 1971, a Utah miner named Steven Kosanke wanted to strip mine the area for sand, igniting a storm of controversy. Several Bay Area conservation groups filed a lawsuit to stop the project. Groups including the Sierra Club, East Bay Regional Parks District (EBRPD), the Environmental Defense Fund, the Antioch Coalition to Save Coal Mines Park, and the Contra Costa Park and Recreational Council felt that the area was too valuable as a recreational resource and that botanical and bird species would not survive the strip mining process.

There are two individuals to note among the list of organizations. The first is John Bryant, the then principal of Heights Elementary School, who conducted field trips with his students at Black Diamond. He and his students located a rare form of manzanita that only exists in that area. The other to note was Congressman Jerome R. Waldie who successfully lobbied the U.S. Department of the Interior to deny Kosanke's sand mining application. With the mining proposal derailed, the East Bay Regional Park District purchased the first 2,640 acres in 1972 at the price of $2.50 per acre. Black Diamond Mines Regional Preserve currently encompasses more than 3,900 acres.

The Nortonville Loop
Hike Option 1
From the parking area, head south on the continuation of the road following the signs for the "Cemetery," "Mines," and "Nortonville." Pass the Stewartville Trailhead on your left, and continue straight on the Nortonville Trail.
The area you are walking through was the site of the mining town of Somersville. Mining began here in 1855, and the town was established in 1859, named after miner Francis Somers. In 1866 the Pittsburg railroad was extended to Somersville to carry coal from the mines to Pittsburg Landing, midway between Pittsburg and Antioch. From here the coal was shipped throughout the Bay Area and northern California.

To fully appreciate the history of the area, stop at the Greathouse Portal for a tour of a mine. The mine tour takes about 45 minutes and is led by a knowledgeable guide. Although the mine itself has been made safe for visitors, a small part has been maintained as-is from its heyday to give visitors a sense of the dangerous conditions that miners faced on the job.

After checking out the mine, continue along the Nortonville trail to the west. Turn right at the sign for the Rose Hill Cemetery and climb a dirt path and some wooden steps to the cemetery's entrance. The cemetery is the resting place of about 200 miners, many of whom died on the job, and miners' wives and children, many of whom died of epidemics that hit this area in the 1870s. Walk uphill through the cemetery past cypress trees and other exotic plants, and exit through the gate and follow the dirt road back to the Nortonville Trail, then head right (west).

The Nortonville Trail climbs to Nortonville Pass, where you will continue to the right on the Nortonville Trail. You might see some of the more than 100 bird species that inhabit this area as you walk along. Red-tailed hawks frequent this area, and elsewhere in the preserve you might see golden eagles, bluebirds, and goldfinches.

As you descend from the pass you enter the valley where Nortonville was located. Here you'll see the remnants of this once thriving mining community, which had its own railroad link to Pittsburg. On July 24, 1876, the Black Diamond Mine exploded, killing six miners. This, coupled with a devastating fire two years later that destroyed much of the town, marked the beginning of a decade-long decline in production for the mine, which closed down in May, 1885, leading to the subsequent demise of the town.

At the end of the Nortonville Trail, go left on the Black Diamond Trail. As you walk you'll see lots of native trees, including blue oaks, coast live oaks, California buckeye trees, and Coulter pines. After about three quarters of a mile on the Black Diamond Trail, you'll meet up with Black Diamond Way, a paved road coming in from your right. Continue straight on the now-paved Black Diamond Trail until you reach a clearing where you'll see a path to the left leading to "Jim's Place," an underground dwelling of unknown origin. After checking out this unique abode, come back to the Black Diamond Trail and go left, continuing on the trail as it winds uphill.

The trail ascends to a ridge, and soon hits a junction with a dirt road on the left, which is the continuation of the Black Diamond Trail. Go left on the continuation of the Black Diamond Trail, and take in the view to the east. From here you might see housing developments that have been marching westward from Antioch into open space and agricultural lands. Think about the value of having protected open spaces like Black Diamond Mines within easy reach of our cities and towns, but also reflect upon how rapid sprawl development threatens to pave over the Bay Area's greenbelt.

Where the Black Diamond Mine trail meets the Manhattan Canyon Trail, you can take a rest on the bench under an oak tree. Continue on the Black Diamond Trail as it begins to climb towards a set of powerlines. Pass through the cattle gate and continue along the trail until you hit the Nortonville Trail, then retrace your steps back to the parking area.

The Sprawlside Loop
Hike Option 2
On the left hand side of the road where Frederickson Lane makes a hard right turn, take the Contra Loma Trail south (left). After a third of a mile, go left onto the Stewartville Trail. Note the Richland property on your left (east) as you walk on the Stewartville Trail. There is fairly good separation between this developed property and the park boundary.

Continue south on the Stewartville Trail uphill and past its intersection with the Ridge Trail. You're now at an edge of the Preserve and have a good view to the east of the area known as Future Urban Area One (FUA-1). If the area around you doesn't look particularly "urban" yet, it may within a few years. Developers want to turn the 2,700 surrounding acres into 5,000 units of sprawl-style housing developments, which will lack services such as retail and public transit. That means the people living here will have to drive everywhere: to work, to go to the post office, even to get a gallon of milk.

In fact, the City of Antioch estimates development of FUA-1 will create more than 140,000 additional car trips each day on local roads and Highway 4, which is already snarled in traffic during the rush hours. The alternative to this type of wasteful sprawl development focuses smart growth development in already developed areas, such as Antioch's historic downtown. Greenbelt Alliance is working with a local group, Citizens for a Better Antioch, to block development of FUA-1 and protect the greenbelt around Antioch.

As large as FUA-1 is, it's also a gateway to development further south, approaching the relatively undeveloped foothills of Mt. Diablo. But building here may be problematic due to the presence of threatened or endangered species like the tiger salamander, the red-legged frog and the San Joaquin kit fox. In addition, the coal mining tunnels that honeycomb this area may pose a construction hazard.

Continue west on Stewartville Trail to its junction with the Star Mine Trail. Go left (south) on Star Mine Trail. You'll pass the Star Mine Group Camp and begin paralleling the westernmost boundary of FUA-1.

Continue past the Group Camp uphill to the old Star Mine itself, then further up through an old sand quarry area. If you like, you can take the branch trail off to the left (east) and after a mile connect with Empire Mine Road.

This 200-foot wide corridor belongs to the East Bay Regional Park District, but the proposed FUA-1 development could run all along its length on the left, while a proposed development at Roddy Ranch would run on the right.

Here's where the hike can get strenuous. Continue on the Star Mine Trail and ascend to its summit. This area has a little bench and features sweeping views of the surrounding area—ideal for a lunch break.

Afterward continue on the Star Mine Trail to the valley below and the old Stewartville townsite, just past the point where the Star Mine Trail again intersects the Stewartville Trail.

At this point you have two options: You can head northeast on the Stewartville Trail back to where you started at Frederickson Lane, or hook up with the Corcoran Trail 300 yards northeast of the intersection of the Star Mine Trail and the Stewartville Trail.

If you choose the latter, continue up the Corcoran Trail three-quarters of a mile to its junction with the Ridge Trail. Here you'll see great views of old Antioch, the Sacramento and San Joaquin Rivers, and previous developments that have been built in the last 10-15 years. Seventy-two percent of the City of Antioch's housing stock has been built since 1970, demonstrating just how rapid this area's growth has been.

Take the Ridge Trail to the east to its junction with the Stewartville Trail and follow it back to Frederickson Lane.

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