An environmental study of a rock quarry proposed in northern San Diego County has survived a second court challenge. The Fourth District Court of Appeal, which had rejected an air pollution analysis in an earlier environmental impact report, accepted a revised version and refused to let project opponents raise the issue of newly identified air pollution from the planned mine.

San Diego County in 1987 approved Palomar Aggregates' proposed quarry on Rosemary's Mountain about two miles east of the junction of Interstate 15 and Highway 76. A group called Riverwatch successfully challenged the EIR in San Diego County Superior Court. The Fourth District overturned most of that decision but found the air quality analysis to be insufficient. (Riverwatch v. County of San Diego, (1999) 76 Cal.App.4th 1428; see CP&DR Legal Digest, February 2000.)

Specifically, the EIR had concluded that air quality impacts would be insignificant because the quarry's processing operations would generate only 95 pounds of airborne dust (called PM 10) per day, which was below the San Diego Air Pollution Control District's 100-pound threshold of significance. However, erosion and hauling of aggregate were expected to generate another 193 pounds of dust per day. The EIR should have considered those emissions in the finding of significance, the court ruled.

Palomar and the county then revised the EIR that re-evaluated the various emissions sources and added mitigation measures to get below the 100-pound threshold. Riverwatch again challenged the document, but the Superior Court this time accepted the study. In an unpublished opinion issued in late October, the Fourth District upheld the lower court.

In the second round of litigation, Riverwatch complained that the revised EIR did not address diesel emissions and additional dust sources related to the project. The court ruled the EIR did not have to do so, because Riverwatch's sole contention in the first round of litigation was that the EIR failed to properly analyze sources of pollution that the EIR had identified.

“Nothing in Riverwatch's pleadings or briefs gave notice to the county, Palomar or the trial court that additional sources of PM 10 or the toxicity of diesel exhaust needed to be considered,” the appellate court ruled. “Contrary to opponents' contention, the project proponent was not required to consider the impact of previously unidentified sources of pollution.”

The case is Riverwatch v. County of San Diego, No. D042430.