Black Diamond Mines Regional Preserve
The Black Diamond Mines Regional Preserve is a park located north of Mount Diablo in Contra Costa County, California under the administration of the East Bay Regional Park District. The district acquired the property in 1973. The preserve contains relics of 3 mining towns, former coal and sand mines, and offers guided tours of a former sand mine. The of trails in the Preserve cross rolling foothill terrain covered with grassland, California oak woodland, California mixed evergreen forest, and chaparral.
History
Indigenous history
Long before the widespread ranching and mining activity that took place in the area, indigenous people had a presence in the Bay Area for 13,000 years. Three Bay Miwok tribes, the Chupcan, Ompin, and Volvon, lived in the areas surrounding the Black Diamond Mines Regional Preserve. The Chupcan occupied territory to the west of the preserve near Concord, the Volvon occupied the territory to the south including much of Mount Diablo, and the Ompin occupied the area to the north including Pittsburg, Collinsville, and the intervening waterway. Black Diamond Mines Regional Preserve is located in a boundary area between these three tribes. At the beginning of the 19th century, these three tribes were significantly impacted by the Spanish mission system. Between 1804 and 1806, the majority of Volvon Bay Miwok were split up and baptized at either Mission Dolores or Mission San Jose. A Spanish military raid caused the Chupcans to flee to Suisun territory in 1804, and by 1811, most Chupcans were split up and baptized at either Mission Dolores or Mission San Jose. In 1810, some members of the Ompin went to Mission Dolores, and the remaining members went to Mission San Jose in the years 1811 and 1812.Mount Diablo Coalfield
In 1859 William C. Israel discovered a coal deposit while clearing out a spring on his land at Horse Haven Valley, six miles south of Antioch. His initial attempt to mine the coal was not financially successful but soon other coal deposits were discovered nearby and mining operations grew rapidly. The area became known as the Mount Diablo Coalfield, producing more than 4 million tons of coal during this time.The area includes the remains of twelve coal mines and the sites of several long-gone coal mining towns. The Preserve contains over of mine workings. The largest and oldest town, Nortonville, had a peak population of about 1,000. Somersville, Stewartville, West Hartley and Judsonville were located in valleys to the east. The sites of Judsonville and West Hartley are located on private property outside the eastern boundary of the Preserve. The mines were the Empire, Central, Star, Corcoran, Pittsburg, Manhattan, Eureka, Independent, Union, Black Diamond, Mt. Hope, and Cumberland. The coal produced was of a low grade, but for a time in the 19th century, was the only readily accessible and economic source in California. Therefore, it was a very valuable resource and powering the railroads, ships and heavy industry of California. The mineral was often called 'black diamond."
The coal was carried to the San Joaquin River by three railroads: the Empire, Pittsburg, and Black Diamond, for shipment by barge to markets in San Francisco, Sacramento, Stockton and other communities. Coal mining activity ended as better-quality imported coal became affordable and as petroleum emerged as an energy source. After the coal mines closed, the towns were abandoned and the area was used mainly for cattle grazing.
In 1973 the Southport Land and Commercial Company donated 160 acres of its land holdings to the East Bay Regional Park District. Early plans for the park considered the name Nortonville-Somersville Coal Mines Regional Park. The park eventually opened on May 8, 1976 as the Black Diamond Mines Regional Park. An additional 176.18 acres of land which includes the former Nortonville town site was acquired by the East Bay Regional Park District in December 1980.
In the period between the mines ceasing operations and the East Bay Regional Park District acquiring the land, many area youths visited the former Nortonville and Somersville town sites for recreation and to explore the abandoned mines. Some were gravely injured or killed due to falls, cave-ins, or asphyxiation from dangerous gases. Immediately after assuming ownership, the East Bay Regional Park District began a mine hazard abatement program to close the coal mines, with assistance provided by the United States Department of the Interior, Office of Surface Mining. Since that time no deaths have occurred within the park. In 1980 four young boys were killed on private land adjacent to the park when they were exposed to methane gas a mile within an unsealed coal mine.
Park staff have maintained a public-access opening into a former coal mine known as Prospect Tunnel. Visitors can explore the first of this approximately 400-foot tunnel.
Rose Hill Cemetery
Rose Hill Cemetery, officially designated as a Protestant cemetery, the final resting place for over 200 residents of the coalfield, is located on a hillside between the Somersville and Nortonville townsites. After the mines closed and the nearby towns were abandoned, the cemetery fell into disuse. Many of the gravestones were stolen or destroyed by vandals, or damaged by cattle using them as scratching posts. In 1960, Ansel Adams photographed two Italian Cypress trees in the cemetery, and called the image, "Poplars, Cemetery near Mount Diablo".Those buried in the cemetery include coal miners who were killed as a result of their work in the mines. However, the majority of the buried are children from the nearby towns of Nortonville and Somersville who died of diseases such as smallpox, scarlet fever, diphtheria, and typhoid.
Few people buried in the cemetery are identified. Many of the individual plots were never marked. More had only a wooden marker – nearly all of which were destroyed over the years by either wildfires that swept through the area or by insects, weather, or other natural cause. Vandals are said to have carried off some of the more permanent stone markers. The original records for the cemetery were destroyed in the 1906 San Francisco earthquake and fire.
The land the cemetery occupies was originally owned by the Black Diamond Coal Mining Company president and chief stockholder Alvinza Hayward, who left it to his daughter Emma Rose upon his death. In the 1940s she deeded the land to Contra Costa County. It was transferred to the East Bay Regional Park District in September 1973. Since that time park staff has undertaken restoration of the cemetery, including stabilizing eroded soil, repairing and reinstalling gravestones, and marking burial sites missing gravestones with brass plaques. They have also sought to recover stolen gravestones, such as an 1883 gravestone for 8-year-old Walter E. Clare that was returned in 2002 by a local family who discovered it buried on their property while replacing a sewer line.
A few whose earthly remains were laid to rest here include:
- William Gething, age 36, who was killed with 10 other men in an 1876 mine explosion; 7 other men who died in the same accident are buried nearby. The citizens of Nortonville raised $300 to erect a white bronze monument to these men, located in the cemetery. The monument was stolen or destroyed sometime after the 1930s.
- Sarah Norton, age 68, wife of Noah Norton, who worked as a midwife and was killed instantly when she was thrown from her buggy on her way to attend a delivery; she reportedly delivered over 600 babies for miners' wives.
- The earliest stone marker belongs to Elizabeth Richmond, who died in February, 1865.
- The youngest known person was the one-day-old, unnamed daughter of Thomas H. and Elizabeth Jenkins, who died on April 15, 1880.
- The oldest known person was Ruth French, age 81, died on September 11, 1874.
- The most recent known burial was William T. Davis, died in 1954.
Sandstone mines
In the 1920s, a mine producing high-quality silica sandstone was started by owner Marvin Greathouse on a hillside above the Somersville townsite. He sold the product to the Hazel-Atlas Glass Company which operated a plant in Oakland manufacturing glass containers. Hazel-Atlas eventually purchased the mine and operated it until about 1945. Another sandstone mine in the Nortonville area produced sand used by the Columbia Steel mill in Pittsburg, California, for steel casting. The two companies recovered more than of sand between from the 1920s to the 1940s. The Hazel-Atlas mine is being restored and maintained by park staff and can be visited on guided tours which cover the area's mining history and geology.Inside the Greathouse portal, a -long section of the entrance corridor has been made into a museum. The first section is a series of self-guided exhibits, while the larger second section, houses a reconstruction of the Hazel-Atlas works as it would have appeared around 1940.
Park staff originally repurposed the Hazel-Atlas mine as a museum in the 1970s, but storm damage in 2007 forced closure of this attraction for extensive repairs. It did not reopen for five years.
Geology
The rich coal deposits and sandstone hills of Black Diamond Mines Regional Preserve were formed by geological activity in the Tertiary period. In the period between the Paleocene epoch and Miocene epoch of the Tertiary era, the North American Plate and the Pacific plate came together at a subduction zone where the North American Plate was pushed over the Pacific Plate. During this era, the Pacific Ocean stretched over much of the California central valley with the coastline reaching the lower regions of the Sierra Nevada mountains. Tectonic activity between the North American and Pacific plate, along with sea level changes, brought about four series of marine sediment deposition. The coal that was mined from the Mount Diablo Coal Field was formed during the third marine sediment deposition cycle which took place during the middle of the Eocene epoch. At the beginning of this third cycle, tectonic activity caused an uplift of the continental shelf seafloor, resulting in the creation of shallow marshes. Erosion during this era brought an abundance of sediment into the shallow sea covering the continental shelf, with some sediment making its way into the marshlands. These sediments, along with the favorable hot and humid climate, fueled the growth of coastal marsh flora that eventually formed into coal. Tectonic activity towards the end of this sedimentation cycle caused the continental shelf to sink and resulted in sediments being deposited into deeper water. The Mount Diablo Mountain Range of today was created at the beginning of the fourth depositional cycle when the continental shelf began to rise up once again.Recreation
The trails offer views of Mount Diablo, the Sacramento-San Joaquin River Delta, and on clear days, the Sierra Nevada.The Preserve usually has an impressive variety of wildflowers in spring including the rare Mount Diablo fairy lantern, Mount Diablo sunflower, and Brewer's dwarf flax. It is home to a variety of wildlife including deer, mountain lions, coyotes, foxes, bobcats, golden eagles, and a variety of hawks. The endangered San Joaquin kit fox and threatened California red-legged frog, California tiger salamander and Alameda whipsnake are present as well. The park is open year-round for hiking, mountain biking, and horseback riding from 8 am to dusk. A backpack camp and a group camp can be reserved for overnight stays. There have been many reports of a ghost in the park.