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California with 115 million tons ranked first in sand and gravel output and produced more than twice as much as second-ranked Michigan. Other States producing substantial quantities of sand and gravel in descending order of production were Illinois, Minnesota, Ohio, Wisconsin, and Texas. Combined production from the seven leading States was 375 million tons, about 41 percent of the U.S. total output. The value of sand and gravel produced in these seven States was $456 million, 40 percent of the Nation's total.

Nationwide commercial operations continued to dominate production with 84 percent of the output, while Governmentand-contractor operations accounted for 16 percent. The number of commercial operations continued to decline from 5,918 in 1970 to 5,738 in 1971.

Factors which had added to the consumer cost of sand and gravel include increased labor costs, growing land values, cost of land rehabilitation and longer haulage distances which increase transportation cost, and the need to produce from lower quality deposits as better ones become depleted or covered by urban expan

sion.

There were 4,676 commercial operations with production under 200,000 tons per year. These operations accounted for 34 percent of the total U.S. production. There were 767 operations with production between 200,000 and 500,000 tons, and they accounted for 31 percent of U.S. production. The remaining 295 operations, with

production over one-half million tons, accounted for 35 percent of U.S. production. The use of larger operating units, more efficient portable and semiportable plants, versatility of plant capacity and greater awareness of pollution control and rehabilitation were the key note of progress in

1971.

Automatic controls were installed in many of the larger and newer operations. These, together with improved equipment, have permitted recovery of salable fractions from deposits previously considered too low in quality for profitable exploitation. The industry continued to expand and improve its operations.

Descriptions of several new mechanized sand and gravel plants were published, illustrating equipment and technology. Special Aggregates Corporation, near Poland, N.Y., built an operation that would in every way protect the local environment, including a unique 350-ton-per-hour sand plant where gravity and water do all of the work except screening. The electric motors installed total 445 horsepower, most of which is used for moving water. A wide range of sand products are made, as well as several uncrushed gravel blends.2

Davison Sand & Gravel Co., of New Kensington, Pa., started up a new dredging operation in the Allegheny River above

1 Mining engineer, Division of Nonmetallic Minerals.

2 Trauffer, Walter E. Unique 350-tph Sand Plant Does All Handling by Water or Gravity. Pit and Quarry, v. 64, No. 7, January 1972, pp. 98-102.

Pittsburgh. They are reworking the beds of coarse gravel wasted in past years. The deposit is mostly 114- to 41/2-inch gravel. Digging of this material is done by a clamshell dredge. The plant capacity is about 300 tons per hour. Most of the product is subbase material for a freeway project.3

As urban land deposits of sand and gravel become depleted, more and more local bodies of water are being investigated for new deposits. Large quantities of good aggregate material has already been extracted in western Lake Erie and also along the Lake Ontario shore line. A study

was started in 1968 to evaluate the distribution and character of the sand and gravel deposits along the New York shore line in Lake Ontario with the intension of extending the study to Lake Erie. The findings have indicated that most of the Lake Ontario nearshore deposits consist of boulder beds of glacial till (75 percent), layers of sand and gravel (15 percent), and bedrock.4

3 Trauffer, Walter E. Wasted Gravel Dredged and Processed for Highway Sub-Base. Pit and Quarry, v. 63, No. 8, February 1971, pp. 84-88.

Woodrow, Donald L., Thomas L. Lewis, and Robert G. Sutton. Lake Ontario As A Source of Sand. Rock Products, v. 74, No. 4, April 1971, pp. 72-73.

Table 1.-Sand and gravel sold or used by producers in the United States,1
by class of operation and use

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1 Excludes American Samoa, Panama Canal Zone (1971), and Puerto Rico.

2 Data may not add to totals shown because of independent rounding.

3 See table 10 for use breakdown.

Approximate figures for operations by States, counties, municipalities, and other Government agencies under lease.

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Figure 1.-Production and value of sand and gravel in the United States.

CONSUMPTION AND USES

U.S. consumption of sand and gravel amounted to 920 million tons valued at $1.1 billion in 1971. The construction industry, the prime user of sand and gravel, consumed 96 percent of the tonnage and 91 percent by value of the sand and gravel output in 1971. Of the amount of sand

and gravel consumed by the construction industry, 50 percent went into paving, 37 percent into building, about 9 percent into fill, and 4 percent into other uses. The principal consumers of higher priced industrial sands were the glass and foundry industries.

VALUE,million dollars

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Figure 2.-Sand and gravel sold or used in the United States.

PRICES

Representative carload-lot prices of sand in 20 cities at the end of 1971 ranged from $1.00 per ton in Detroit to $6.25 per ton in Atlanta, according to the Engineering News-Record. The average of the sand prices reported was $3.23 per ton, compared with $3.03 per ton in 1970. Prices for either 4 or 112-inch gravel ranged from $1.70 per ton in Cincinnati to $7 per ton in New Orleans. The average of the 3/4-inch gravel prices reported for 18 cities was $3.67 per ton, compared with $3.18

per ton in 1970. For 12-inch gravel, the average for 15 cities was $3.48 per ton, compared with $3.06 per ton in 1970. The average value of sand and gravel sold or used by producers, f.o.b. plant, was $1.25 per ton; the comparable value in 1970 was $1.18 per ton.

The average price of sand in Montreal and Toronto, Canada, at the end of 1971. was $2.90 per ton; 3/4-inch gravel was $3.20 per ton, and 11/2-inch gravel was $2.60 per

ton.

FOREIGN TRADE

Canada received 83 percent of U.S. exports of construction sand, the Bahamas received 12 percent, and Mexico received less than one percent. The remainder went to 28 different countries. Exports of construction sand totaled 328,471 short tons, valued at $903,357. Canada received 89 percent of U.S. exports of common sand and gravel, the Bahamas received 8 percent, and Mexico received 3 percent. Total exports of common sand and gravel were

520,127 short tons, valued at $743,039. Of U.S. exports of industrial sand, which amounted to 879,142 short tons valued at $5,098,570, Canada received 78 percent, Mexico 14 percent, and the Bahamas about 4 percent. The remainder went to 60 different countries.

Most of the crude sand and gravel imported in 1971 was from Canada. Almost all of the imported glass sand was from Australia.

WORLD REVIEW

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Austria.-Proposed new legislation protect water sources from pollution presents problems for the aggregate industry. A complex procedure was proposed in connection with this legislation, including a hydrographic survey and test drill holes for water table fluctuation. Regular chemical and bacteriological analyses were demanded, and regulations stipulated that no dry operation can be opened in areas where underground water must be protected.5

Canada. The Consolidated Sand and Gravel Company has put into operation a new 800-ton-per-hour plant near Stouffville, 30 miles northeast of downtown Toronto. Eventual production of the plant will be 1,000 tons per hour of finished products. It is capable of producing twelve standard sizes of aggregates. Site rehabilitation is an integral part of the operation. Worked-out areas are being graded and reclaimed with top soil.6

The aggregate industries, which are among the largest and fastest growing in the primary sector of the Ontario economy, are receiving governmental attention. The government has been involved in regulating the quality of the environment during and after operations. Efforts are being made to increase the understanding of the diverse elements of the sand and gravel industry, to make them more compatible with the environmental aspirations of society.

United Kingdom.-In the United Kingdom there are over 1,000 firms with interests in sand and gravel. Production of sand and gravel in 1971 was about 120 million

short tons. Owing to a great deal of integration during the past decade, the industry is dominated by a small number of very large firms. About 43 percent of the aggregate market is held by six leading producers and the first 12 producers hold over one-half. This has resulted in a reduction in the number of workings, and a very large increase in the average production per pit. It is estimated that the annual production of sand and gravel pits increased from 37,200 cubic yards in 1957 to 66,900 cubic yards in 1969. Ready Mixed Concrete Ltd. (R.M.C.) was the largest producer, with an estimated 18 to 19 million tons of sand and gravel per year.?

Based on trends in the aggregate industry in United Kingdom, it is predicted that the industry will ultimately be comprised of fewer and larger groups controlling a much greater slice of the industry, because of competition, shortage of reserves, and the necessity to improve the return on capital. Also, aggregate prices will have to be raised to cover increased costs. It is predicted that the optimum size of the majority of operations will be an output of one-half million tons per year, with a few in the 1- to 3-million-tons-per-year bracket. Reserves of aggregate may become critical unless there is a major change in planning policy. Sea-dredging sources are not consid

The Quarry Managers' Journal. V. 55, No. 5, May 1971, p. 145.

Rock Products. V. 74, No. 8, August 1971,

p. 18.

1 Industrial Minerals. No. 49, October 1971, pp. 9-23.

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