Urban pressures on quarries spills over in Maricopa County
Proposed copper mines in Arizona are getting most of the news headlines these days, but a more common issue both here in Arizona and across the nation, is the encroachment of housing on sand and gravel quarries.
To be economically viable, quarries have to be as close as possible to where the materials are needed for construction. A rule of thumb is that for each 30-40 miles additional that sand, gravel, or aggregate must be hauled, the price doubles. And that dramatically increases the cost of construction. So, quarry operators try to find areas adjacent to urban areas but away from areas that are likely to be developed in the near term. In fast growing Arizona, that hasn't always worked out, and many quarries are now surrounded by new residents who want the industrial operations shut down.
Such a controversy apparently has been brewing in the towns of El Mirage and Youngtown in northern Maricopa County, just west of Sun City. The area has undergone massive residential development, hemming in the Agua Fria River on all sides, including a long-established aggregate quarry. El Mirage is reported to have dropped a plan today to annex a 240 acre quarry owned by the Salt River Materials Group, which is owned by the Salt River Pima-Maricopa Indian Community. The initial intent had been to give El Mirage more control over the mining operation. But the Arizona Republic reports that Youngtown residents were opposed to the annexation. [right, Google Map view of Agua Fria River between El Mirage, Youngtown, and Sun City]
Another possible factor, not mentioned in the news story, is a new state law that requires local governments to factor in aggregate and sand and gravel resource availability in their land use plans.