LOS ANGELES (CBSLA.com) — A UCLA study released Tuesday found that while Los Angeles County’s air quality has gotten nominally better, the area’s groundwater and stormwater have excessive levels of pollution.

Los Angeles County’s environment earned a “C+” grade, according to the report.

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“Despite a strong recent history of environmental improvements, the county has a long way to go before joining the honor roll,” said Mark Gold, acting director of UCLA’s Institute of the Environment and Sustainability. “There’s tremendous room for improvement in all six environmental areas.”

The report rated the county based on its water, air, ecosystem health, waste, energy/greenhouse gases and quality of life. The county earned C grades in most areas, but scored Bs for waste and energy/greenhouse gases.

In the waste category, however, the county received a “B/incomplete,” with Gold saying there is no data tracking how much waste is being recycled.

“Despite the fact that all cities in the region comply with state solid waste management laws, we don’t have the data to determine who much waste is recycled or diverted from disposal in landfills,” he said.

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The institute’s Felicia Federico said one problem researchers discovered locally was that there are “enormous data gaps” and some indicators of environmental conditions “aren’t measured at all.”

“As a region we need to decide what the most important environmental measures are that we want to track and determine how we will do so regularly,” she said.

The report also found that despite large increases in water conservation, the county imports more than half of its water, and the per capita water use is more than double that of Europe and Australia. It also found that the county’s per-capita electricity use is among the lowest in the nation, but much of that power came from coal.

Air quality has improved substantially over the last 45 years, but the region still frequently violates federal standards for ozone and particulate matter, according to the report.

“We no longer have full days when children can’t go outside to play,” Gold said. “But lots of areas in the L.A. region have populations exposed to unacceptably high levels of cancer risk due to the air quality, especially in low-income areas, so we have significant environmental equity issues.”

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