Rock Products - The Leading Voice of the Aggregate Industries.

Rock Products 120th Anniversary - Part 8

In This Issue, We Cover The Years 1960-1969.

The first part of our historical account of the 1960s appeared in the January issue. This is Part Two. – Ed.

26 120YEARS 400For many years, aggregate producers examined new equipment at two separate exhibitions, one sponsored by the National Sand and Gravel Association (NSGA) and the other by the National Crushed Stone Association (NCSA). Following negotiations that began in 1962, the associations merged the two shows. The first combined show was held in February 1964 in Chicago.

Not all attempts to introduce new technology, however, were successful. In a 1962 report on the use of building materials in the highway program, the Bureau of Public Roads said, “The favorable trend in drilling and blasting is expected to continue and, in the not too distant future, quarrying operations may be improved by the introduction of electromagnetic radiation, ultrasonic methods, or perhaps nuclear explosives in isolated areas to reduce solid rock into processing size.”

The Atomic Energy Commission (AEC) picked up on the idea and, in its effort to develop industrial uses for nuclear explosives, suggested at the Highway Research Board’s annual meeting in 1964 that aggregate could be a by-product of a nuclear explosion. The AEC estimated that a 100-kiloton, deeply buried detonation would produce more than 15 million cu. yd. crushed stone for less than $1 million. Atomic scientists said the blast area probably could be entered for normal work within four days after detonation.

The idea was taken seriously enough to make the June 1965 cover of Rock Products. An article on the subject said, “nuclear explosives, the newest way to an ‘instant quarry,’ have come out of the experimental stage and promise to be the safest, cheapest, most versatile of all blasting methods.”

ROCK PRODUCTS ranking of the Top Ten

crushed stone OPERATIONS IN 1968




Est. Annual Production


U.S. Steel

Rodgers City, Mich.



Material Service

Thornton, Ill.



Vulcan Materials

McCook, Ill.



Inland Lime & Stone

Gulliver, Mich.



New York Trap Rock

Clinton Point, N.Y.



Presque Isle Corp.

Stoneport, Mich.



Bethlehem Mines

Hanover, Pa.



Huron Portland

Alpena, Mich.



Solvay Process Div.

Jamesville, N.Y.



Kaiser Cement

Permanente, Calif.


million short tons
Struggling with Costs and Over-Capacity

Problems in the rock products industry were compounded in the last half of the 1960s by general economic and political conditions in the United States. Higher inflation rates and tighter money supplies created a slump in residential construction, and inflation essentially consumed increases in federal outlays for highway construction, resulting in little real growth. Aggregate production increased just 7 percent from 1967 to 1970; cement production increased 5 percent.

Government apportionments for interstate construction came under attack for a number of reasons:

  • Cuts in non-military spending were necessary to support the effort in southeast Asia. By 1968, the United States had more than 500,000 troops in Vietnam.
  • Cuts in overall government spending were thought to help stem inflation.
  • Increased government funding for mass transit-system construction was gaining support in order to ease growing traffic congestion in large cities.
  • Increased focus on environmental issues, in particular air pollution, required government-funded studies.

Federal officials began to doubt the government’s ability to finance and complete the interstate system. Of the more than 22,000 miles of interstate highways open to traffic by 1967 (only about 54 percent of the planned system), about 25 percent were already deemed inadequate for traffic expected in the 1970s. Many in Washington called for future efforts to be directed toward urban freeways and mass transit instead of more interstates.

But interstate interests prevailed. Late in 1968, Congress and President Johnson approved a Bureau of Public Roads plan to add 1,500 miles to the original 41,000-mile interstate system. And the victory of Richard Nixon in the presidential elections gave the rock products industry confidence that support for highway construction would continue. Nixon supported interstate construction as vice president during the Eisenhower administration when the Highway Act of 1957 was enacted.

The Environment

44 120TH 400On the environmental front, concern continued to grow throughout the late 1960s. In 1970, in an environmental message to Congress, President Nixon described the problem as “the inevitable by-product either of advancing technology or of growing population. It results not so much from choices made as from choices neglected; not from malign intention, but from failure to take into account the full consequences of our actions.”

Shortly afterward, the president’s Advisory Council on Executive Reorganization recommended forming an independent agency: the Environmental Protection Administration. It would incorporate the Federal Water Quality Administration from the Interior Department and the National Air Pollution Control Administration from the Housing, Education, and Welfare Department.

Although increased federal regulation was not desired, emphasis on control of air pollution did offer hope for some rock products producers. Early research and pilot studies indicated that limestone could be used by coal-burning power plants to neutralize sulfur dioxide emissions. But such environmental uses were considered only a “promising field” at the time.

Passage of the Federal Metal and Nonmetallic Mines Safety Act late in 1966 had signaled the trend toward further government intrusion into the industry’s activities. In a speech at the NSGA’s 1968 annual convention, Vincent P. Ahearn Sr., retired managing director said, “Management must be concerned with the quality of government at all levels and must carefully maintain historical perspective and a sense of humor. State sovereignty is in a steady decline, and the governors are the pallbearers.”

The Federal Safety Act established advisory committees, with representatives from government, labor and industry, to develop proposed standards. The result was 155 mandatory and 155 advisory standards, which were published in the Federal Register in 1969 and became effective July 31, 1970.

This increased government oversight and little real growth in highway construction added to the frustrations of aggregate producers. Also, minor price increases were wiped out by soaring labor costs, and specification changes required more processing to make smaller sizes of aggregate.

The industry’s answer was to build larger, more highly automated plants and to use larger loaders and haul trucks. Livingston-Graham’s El Monte, Calif., operation near Los Angeles was reported to be the world’s largest sand and gravel plant with a capacity of 3,000 tph. It also boasted the industry’s largest screens (8- x 20-ft. double-decks), largest haul trucks (100 ton), and a 15-cu.-yd. shovel and 7-ft. cone crushers.

As late as 1967, experts said that although computerized process control was a proven part of cement manufacturing, it was beyond the needs of the aggregate industry. The experts were wrong. In 1968, Kaiser Sand and Gravel announced it would install a computer as part of its process control system at its Radum, Calif., plant, to be online in 1969. The success of this and later applications solidly established a place for computers in aggregate-processing facilities.

Cement Industry Developments

47 120TH 400It would take more than computer controls, however, to help the cement industry, which still was haunted by overcapacity and depressed prices. Scheduled price increases in the Midwest in 1967 were rolled back before they even took effect. Only one new cement plant went on line in 1968, replacing an older plant with similar capacity, and two new plants in 1969. As construction and modernization plans were cancelled or delayed, activity reached its lowest level in 15 years.

Lime-kiln construction, on the other hand, was on the fast track. The basic oxygen process for steel production and a rapidly growing market for soil stabilization was lifting the demand for lime to record levels. Shortages appeared in parts of the country and the industry involved in the largest capacity expansion in its history. During 1964 and the first half of 1965, lime plant capacity totaling 4,550 tpd was constructed. In 1967, projects to add 6,226-tpd capacity were announced or underway.

A concern of the lime industry was if it did not meet the demand of the steel industry, the steel industry would install captive lime facilities at its mills. In fact, captive lime production did increase when Bethlehem Steel built its own plant.

Activity in the steel industry also affected slag producers. Increased steel production helped increase the amount of raw material available; however, advancing technology resulted in a dwindling supply of blast-furnace slag. Producers tried upgrading lower-quality stockpiled material as well as introducing heavier slag, especially for railroad ballast.

Increased emphasis by highway engineers on the skid resistance of the asphalt aggregates improved the market for slag as well as lightweight aggregate during the late 1960s. Test methods were controversial, but in many areas highway departments were paying higher prices for skid-resistant aggregate. In 1968, Vulcan Materials Co. and the National Slag Association initiated a SOS marketing program: Stamp Out Skids.

Although technology for mining and processing aggregate and manufacturing cement and lime continued to evolve during the late 1960s, Rock Products reported few significant developments.

As the size of wheel loaders continued to increase, producers used them more in face-loading and load-and-carry applications, causing a running battle between shovel and wheel loader manufacturers. A 1968 Rock Products article comparing the two types of machines stated, “on most jobs, a power shovel (not hydraulic) with a particular bucket size will produce about the same amount of material over a given time as a tractor shovel (wheel loader) with twice the bucket capacity.” The cost of a 6-cu.-yd. shovel, with an estimate 16-year working life, was about $230,000. A wheel loader, with an estimated 5-year working life, cost about $148,000.

Other interesting new products at the time:

  • Trojan introduced a wheel loader with two articulating joints. The operator’s cab, transmission, and fuel and hydraulic fluid tanks were mounted in the middle section of the three-section machine.
  • Hydraulic Machine Co. developed a 15,000-ft.-lb. hydraulic hammer, rated for 100 impact cycles per minute, to mount on hydraulic backhoes.
  • European cement manufacturers were installing stockpiling and reclaiming equipment for homogenizing raw materials for dry-process kilns to improve efficiency and product quality.