The criteria Texas uses to determine how much — and whether — to clean up abandoned industrial facilities, waste dumps and other polluted sites are so lax that they may allow residential homes to be built in areas that neighboring states wouldn’t even consider safe for factories or oil refineries.

That’s according to a report by the Texas Campaign for the Environment Fund set to be released on Tuesday that compares benchmarks for more than 80 different pollutants that Texas, Arkansas, Louisiana, New Mexico, Mississippi and Oklahoma use to determine whether a site is contaminated enough to warrant cleanup and how much pollution should be removed from the soil or water there before it can be re-developed.

The overarching conclusion of the report: Texas’ formulas are “substantially weaker” than those used by almost every nearby state, in part because it tolerates a greater risk of cancer. That means that some polluted Texas sites that would be eligible for cleanup in other states may not be eligible here — and if the state does decide to clean them up, it may not remove as much pollution as its neighbors.

While some neighboring states — namely Arkansas and Oklahoma — rely on federal criteria, Texas uses its own benchmarks. Overall, they are so weak that Texas allows “pollution concentrations on land designated for residential uses that Louisiana, Arkansas, Oklahoma, and Mississippi wouldn’t even restrict to industrial uses,” the report found.

For example, Texas’ cleanup rules say that the ground at residential properties should contain no more than 69 milligrams of the carcinogenic petrochemical benzene for every 1 kilogram of soil; Louisiana, meanwhile, only allows 3.1 milligrams of benzene per kilogram of soil — and that's for sites intended for industrial use.

The report comes a year after heavy rains from Hurricane Harvey flooded many polluted sites in the Houston area, sparking concerns about contaminants leaching into homes and waterways. And statewide, rapid urban revitalization and population growth means many contaminated sites are being remediated and redeveloped for both commercial and residential use.

Almost all of the 5,533 polluted sites in Texas that have been identified as needing some amount of cleanup are enrolled in state-run cleanup programs, according to the report, while only about 7 percent are enrolled in federal cleanup programs. One percent are enrolled in the federal Superfund program, which is generally reserved for the most highly polluted sites in the most urgent need of cleanup. The state’s environmental regulatory agency, the Texas Commission on Environmental Quality, also is responsible — per U.S. Environmental Protection Agency requirements — for determining which sites are eligible for the Superfund program.

The report also found that Texas’ benchmarks are significantly weaker than those used by the federal government to determine whether a site is eligible for Superfund status.

“On average, for all chemicals targeted by Texas and the EPA, the strictest Texas benchmarks tolerate soil pollution at a rate nearly 14 times greater than the benchmarks used to score potential Superfund sites and groundwater pollution at a rate nearly 35 times higher,” according to the report, which emphasizes that the disparity is particularly stark for carcinogenic contaminants.

While Texas benchmarks for pollutants that are not thought to cause cancer are 4.5 percent stronger than federal Superfund thresholds, the report found that they are 1,682 percent weaker for known carcinogens.

“It is fair to say that the more dangerous a pollutant, the less emphasis Texas puts on cleaning it up,” the report concludes.

In a statement, the TCEQ said its cleanup standards were “developed based on broad-based stakeholder input” and “are the result of sound science and uniform methods that assess risk at each site using conservative assumptions to be protective of human health and the environment.”

The report found that the benchmarks in Texas are weaker in part because the state assumes “that Texans are smaller on average than people in other states, that they drink less water, and that children accidentally consume less dirt.”

“As a result we accept greater levels of pollution in our soil and water,” the report says.

But the report found that an even bigger factor was that Texas tolerates a higher cancer risk than other states. In Arkansas, Oklahoma, Louisiana and Mississippi, benchmarks are based on an amount of pollution that would likely cause one additional case of cancer for every 1 million people. Meanwhile, Texas’ benchmarks tolerate an additional case of cancer for every 100,000 people (New Mexico uses the same standard).

The report recommends adopting a more conservative cancer risk level and revising formulas to match assumptions of accidental soil consumption and body size that are used in other states, either through legislation or TCEQ rulemaking.

For the report, the Texas Campaign for the Environment Fund and Air Alliance Houston also requested files on TCEQ investigations of at least 818 potentially contaminated sites from 2007 to 2017. Most of those probes ended with a determination that no further action was necessary, even in some cases when evidence suggested that pollutant levels exceeded state benchmarks and where the EPA later deemed the site a cleanup priority. The report noted that many of the investigation reports omitted specific pollutant concentrations — or lacked a thorough explanation of why the agency decided no further action was warranted.

In May, the EPA added — or proposed to add — two polluted Texas sites to the Superfund program’s National Priorities List that the TCEQ had previously determined required no further action, according to the report. They include a former metal forging and fabrication business in Grande Prairie that the TCEQ decided not to clean up because “the area was not on well water,” the report says, and a long-troubled metal plating facility in San Antonio the TCEQ had investigated and ordered to remove vats and drums. While the agency found “elevated levels” of the toxic liquid bromodichloromethane at the facility, it was below state benchmarks so no further action was taken.

The EPA eventually added the San Antonio site to the Superfund list because it was concerned it may contaminate the Edwards Aquifer, which provides drinking water to some 2 million people. It found that the soil and groundwater at the site are contaminated with heavy metals and cyanide and that concentrations of hexavalent chromium — a toxic carcinogen — exceeded maximums set in the federal Safe Drinking Water Act.

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