More than two dozen target shooting sites at the Table Mesa Recreation Area just north of Phoenix have excessive levels of lead and arsenic in their soil, according to a report commissioned by the Bureau of Land Management and obtained by Phoenix New Times.
The preliminary study was completed in August 2015, but it does not appear to have ever been made public, and its findings have not been reported until now. The BLM has taken a handful of precautions to warn the public, and Table Mesa, an 11,500-acre area near Black Canyon City, remains open for use.
In 2018, the agency began posting warning signs at Table Mesa's dispersed target shooting sites, said Leon Thomas, the BLM's Phoenix district manager. About three years ago, it imposed a moratorium on volunteer cleanups at the site.
The agency is awaiting a follow-up report, which Thomas said he expected to receive in December.
The 13-page document from 2015 included summaries of results and descriptions of methodology, but it did not include appendices, which the report said contained specific data from each of the 183 soil samples tested.
Rem Hawes, a spokesperson for the state office, provided the report to New Times upon request but said he did not have the appendices.
The BLM lists Table Mesa as a recreational area offering target shooting and trails for off-highway vehicles. It is also used for hiking, camping, mining, and dirt biking.
Pioneer Technical Services, an environmental services company based in Butte, Montana, completed the assessment for the BLM's Phoenix District Office.
Its objective was to identify areas where contamination from target shooting could pose risks to humans and the environment. People have gone to Table Mesa for target practice for many years, the report said, but in the past decade, "the use has intensified significantly."
Pioneer collected three to 11 soil samples from 31 informal target shooting sites, which, the report said, were scattered with "trash, litter, old targets, and bullet and shotgun casings."
They brought with them an X-ray-based analyzer, which they used in the field to measure levels of lead, arsenic, antimony, copper, and zinc — elements used in ammunition and commonly found in soils around target shooting ranges.
Pioneer also gathered five background soil samples from areas that were not used for target shooting, but only arsenic levels exceeded state limits, and only in three of those samples.
Of the 31 target shooting areas, 24 had soil samples with lead that exceeded the state limit of 800 milligrams of lead per kilogram of soil. In those areas, lead levels were generally two orders of magnitude above background amounts.
At least one sample from each of the 31 sites had excessive levels of arsenic, and three areas had excess amounts of antimony, a flaky, toxic element. No areas had excess levels of copper and zinc.
The report itself did not state the exact levels of lead or arsenic found in samples, which are in the appendices that the BLM could not provide.
Pioneer also sent one sample per site to a laboratory in Minnesota to confirm results from the X-ray-based analyzer. The lab results for arsenic tended to be lower than results from the field, but the levels of lead shown in lab testing were often significantly higher than amounts found with the X-ray analyzer, the report said.
The discrepancy in lead results could be due to bullet fragments in the soil samples, the report suggested, and Pioneer recommended sending all soil samples for lab testing.
The report served as an initial review to identify potential sites of concern and to test for potential contaminants.
In its report, Pioneer recommended follow-up testing to better compare background concentrations of arsenic and lead with those found in the soil samples. It also suggested conducting a risk assessment "to further refine the actual risk to human health and environment" and further evaluation to prioritize cleanup at the highest-risk areas.
Thomas, the Phoenix district manager, said that the upcoming report due in December — more than four years after the preliminary assessment came out — would cover all of those recommendations.
It would answer questions about the full scope of arsenic and lead contamination, and it would include a strategic plan for cleanup, he said.
Four years between the two reports did not count as "slow," he added, noting, "There are a lot of moving parts in the process. At no point in time did we ever just sit on the report."
Prior to commissioning the second report in 2018, the BLM conducted an internal risk assessment and consulted with the Arizona Department of Environmental Quality. The assessment laid out safety protocols for volunteer trash cleanups, like not eating or drinking while out there, Thomas said.
Formal volunteer cleanup sessions were put on hold about three years ago, he added, and the BLM asked the organization Tread Lightly!, which organizes those outings, to help spread the word.
He maintained that the overall risk for someone who periodically visits those sites at Table Mesa was nonexistent.
“Someone going out there to recreate, just to clean up once or twice, wouldn’t be exposed to any levels that’d be hazardous to them," he said.
Nevertheless, last year, the BLM began posting at least 20 warning signs at rec shooting sites, he said. A photo of one of them, which Thomas shared with New Times, shows a yellow sign with black lettering fixed to a pole pounded into the ground.
In English and Spanish, it advises caution but does not refer to specific problems at Table Mesa.
"Ammunition products contain lead and arsenic which may pose a health hazard if ingested, inhaled, or absorbed through the skin," it reads. "Avoid contact with surface materials. Thoroughly wash hands, footwear, and clothes if contact occurs."
Thomas said he did not have a reason for why the preliminary report from 2015 was never posted online, although he implied that the results from that report were just that — preliminary — and that the upcoming report would provide more reliable findings.
"We did a risk assessment. We have a study going on out there to see what the exposure is," he said. "I honestly think that taking the [upcoming] report and seeing what the report says and reacting to the actual science and data is the most responsible thing to do. So that’s what we’re doing.”
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It is not clear what actions the BLM could take to protect the public once that report comes out, and Thomas said he did not want to speculate.
Whether the BLM should allow recreational target shooting on the lands it manages is highly controversial.
In August, environmental groups sued the BLM and the Department of the Interior over its decision to allow target shooting in 89 percent of Sonoran Desert National Monument, west of Phoenix, despite concerns about damage to saguaros, lead contamination, and fatal stray bullets.
In the past, the National Rifle Association publicly has taken credit for keeping target shooting alive on that swath of BLM-managed land.