Riverside County's mining barons have holed up for decades in the soft hills above Interstate 15, dynamiting hundreds of acres to extract the raw ingredients of concrete, roof tile and asphalt for construction across Southern California.
Now the stuff is being used to build new homes next door, and some of the pit kings feel as though they're digging themselves into a hole with every shovelful.
"They're moving in and trying to kick me out, but we're providing the materials to build their houses," Larry Werner, owner of Werner Corp. Sand & Gravel, said of his new neighbors -- so-called "active" retirees at the upscale Trilogy development.
"I do know there's a rock quarry there," said Mary Lou Luna, 56, who moved to Trilogy with her husband a year ago. "It gets a little noisy. You see the smoke."
Neighbors such as Luna are Werner's worst fear.
"We have the heaviest industry land use on Earth right here -- mining," he grumbled. "Then they go and put the most sensitive land use on Earth right over the fence -- senior citizen housing. They call that planning!"
Until recently, there was always plenty of elbow room in the Inland Empire, and little known Temescal Canyon south of Corona was no exception. Wide open-pit mining, a landfill, a roadhouse saloon or two and a nudist camp have all co-existed in this alluvial valley bisected by I-15. Massive gravel, brick, sand and clay mining operations extract 20 million tons of construction materials worth an estimated $100 million from the hills every year, according to the Southern California Rock Products Assn. On one flank, Minnesota Mining & Manufacturing Co., better known as the maker of 3M brand Scotch tape, extracts rare roofing material.
The average Californian requires more than 6 tons of concrete annually, between road repaving and home, school and mall construction, according to U.S. Bureau of Mines figures. The raw materials are found in plentiful supply locally, but residential development in coastal Los Angeles, Orange and San Diego counties has steadily shoved pit surface mining inland.
Temescal Canyon helped filled the void. A unique confluence of warm- and cold-water creeks, combined with eons of earthquakes and uplift of ancient ocean floor along the Elsinore fault, have sloughed tons of rock off the Santa Ana Mountains to the valley and foothills.
"It's a pretty interesting and unique combination of mineral commodities," said county engineering geologist Wayne Harrison, who said the rich deposits have made the canyon "the poster child of clustering" when it comes to mining.
"We have the finest supply of minerals west of the Rockies," boasts Joyce DeLeo, whose husband, Jerry, owns Corona Clay, where material is manufactured for ball fields.
DeLeo is one of a dozen mine owners who have long considered "being a good neighbor" to mean hoisting a few dozen back-country residents over Temescal Creek in a bucket loader when it flooded in the springtime.
But these days, it's hard to miss the signs of change. A welter of billboards crowds the freeway, exhorting wannabe home buyers. Huge grading machines scrape and level the land for row after row of wood frame houses. Shopping malls and condo villages are built atop abandoned quarry pits.
"It's an emerging area, and we see big opportunities," said Retreat developer Jim Previti, whose homes are selling for up to $1 million apiece. "A lot of people never would have dreamed of it five or 10 years ago."
As Werner sits in traffic on the increasingly sluggish I-15, or glances over the chain-link fence ringing his vast surface mines, he remembers the fate of his father and other mine operators who were pushed out of Orange County a generation ago. With another 30 years' worth of reserves left in the ground, he has swung into action, spending millions to try to hide his entire, behemoth operation.
He has hired sound consultants, built a 50-foot-high berm and covered it with large, dust-obscuring trees. He even won an exemption from federal regulators to allow his equipment operators to use a strobe light warning system at night if there is a problem in the pit, rather than a piercing whistle."Our objective here is to encapsulate ourselves. The reality is the homes are coming. They're already down front, and now they're coming up the side," said Werner. "We're going to do our best to be good neighbors."
There are new neighbors aplenty. The Inland Empire has added nearly half a million new residents in the last three years, and 2.5 million more are expected to arrive by 2030, according to planners. In Temescal Canyon alone, 22,000 new homes are under construction or on the drawing boards, according to developers and county planners.
Economists say it would be no great loss if mining were to go away in Riverside County.