RECLAMATION OF THE LANDSCAPE 329 



years. Crushed stone demand for concrete and roadstone purposes 

 alone runs at about 50 percent of sand and gravel demand, and there 

 is presently no reason to expect much change in that relation. In 

 short, it is reasonably predictable that production of these construc- 

 tion aggregates in the next 20 years will be 3 to 85/2 times what it 

 has been in the last 1 9 years. 



As might be expected, where most marketing areas are generally 

 limited to an area within 30 to 50 miles of the site of extraction, the 

 degree of criticalness of presently available reserves varies widely 

 across the country. Some limited information available to the Na- 

 tional Sand & Gravel Association has indicated that reserves of sand 

 and gravel held or controlled by a representative sample of producers 

 have an average remaining life at recent rates of production ranging 

 from over 40 years in Alabama and Mississippi to about six years in 

 Connecticut and Minnesota. In the Los Angeles metropolitan 

 area one of the largest construction markets in the world reliable 

 testimony before a California legislative committtee pointed out the 

 probability that every acre zoned for sand and gravel extraction 

 at the time of the investigation would be depleted by 1975. It was 

 testified that known deposits near those presently being worked could 

 add about 15 years' supply if zoning authority will protect these 

 additional areas from encroachment and permit extraction. Other- 

 wise, it was estimated, transportation from more remote areas into 

 this urban construction market will probably add in excess of $70 

 million a year to construction costs in the area. 



The public interest requires economical and orderly development 

 of all natural resources the surface of the land the water the 

 minerals. Orderly development needs recognition by all interests 

 the public, conservation people, planning people, and the extractive 

 industries of the benefits of planning for multiple use of land. 

 Multiple use allows extraction of the mineral values followed by 

 preparation of the land for any number of facilities and uses park- 

 land, recreation areas, homes, commercial and industrial establish- 

 ments, sewage plants, water reservoirs, and to the alarm of many 

 people sanitary landfills. Many companies in the sand and gravel 

 and crushed stone industries have in the past and are now accom- 

 plishing suitable afteruse, not only in recognition of a public duty, 

 but also to the operators' economic benefit. 



Just a word about sanitary landfills. The proper disposal of the 

 tremendous amounts of solid refuse generated by urban-suburban 

 complexes is becoming increasingly expensive and critical. Con- 



