Nearly three years after a potentially explosive fire destroyed a Winston-Salem fertilizer plant and prompted a voluntary evacuation affecting thousands of nearby residents, state environmental officials have advised the site’s owners to move forward with cleanup efforts “as soon as possible.”
And while questions remain about chemicals, metals and fuel that were discovered underground after the 8-acre Winston Weaver Co. property was cleared, those substances pose no immediate threat to neighbors, N.C. Department of Environmental Quality hydrologist Thomas Moore said in a phone interview with the Winston-Salem Journal.
“There’s not a risk to the community,” Moore asserted. “But we would say that there is some additional assessment that needs to be conducted before we completely have the full picture of how far the contamination has gone and what next remedial actions will be necessary.”
Those potential remedies include removing soil, installing a system to withdraw and treat tainted groundwater and applying a deed restriction that limits future use of the tract, he added.
In a Nov. 5 letter, Moore informed Winston Weaver that DEQ’s Inactive Hazardous Sites Branch had determined the fire site at 4440 N. Cherry St. is “eligible for approved cleanup” without direct state oversight.
To participate in the process, the company must hire a private environmental consulting or engineering firm approved by DEQ to “implement and oversee the remedial action and enter into an administrative agreement” with the state, the letter stated.
Shifting responsibility to a private firm through DEQ’s Registered Environmental Consultant Program “allows us to focus on sites that are a priority or higher risk,” Moore added.
The letter gave Winston Weaver 30 days to reply, but the company has since requested an extension of the deadline, Moore said.
Mike Spence, the Winston Weaver representative listed in the correspondence, did not respond to a request for comment.
Collin Day, regional supervisor in DEQ’s Waste Management Superfund Section, noted that Winston Weaver is not legally obligated to take part in the recommended program.
“Even though the cleanup standards guidelines are the same, a lot of parties elect not to participate,” Day said.
If Winston Weaver opts out, DEQ will maintain direct oversight.
“We’re not going to cut and run on this,” Day insisted.
In an email sent Nov. 5, the same day as his letter to Winston Weaver, DEQ’s Moore offered a concise assessment of the state’s position.
“Based on discussions with you and the proposals in the report, the REC program appears to be the best avenue to pursue site closure,” Moore wrote to Spence, the company representative. “Consequently, we would encourage you to start this process as soon as possible.”
Explosive material improperly stored
The blaze broke out Jan. 31, 2022, took days to extinguish and led to a voluntary evacuation affecting about 6,000 people over concerns that an estimated 600 tons of stored ammonium nitrate could trigger what Winston-Salem’s fire chief suggested could have been “one of the worst explosions in U.S. history.”
Blinding smoke engulfed portions of the city for days and, at one point, EPA monitors reported air particulate levels seven times higher than what the agency deems “hazardous.”
Runoff from more than 4.2 million gallons of water used to fight the fire sent chemicals into nearby creeks, killing fish and prompting the city to issue alerts encouraging residents to avoid those waters.
N.C. Department of Labor investigators concluded that improperly stored ammonium nitrate — a common ingredient in fertilizer — may have heightened the risk for a destructive, deadly blast, according to documents obtained by the Journal through a public records request.
The AN stored at the Winston Weaver facility was 20 times what was present at a Texas fertilizer plant when it exploded in 2013, killing 15 people (including a dozen first responders), injuring 250, leveling an entire block, and damaging or destroying more than 150 buildings, including two schools and a nursing home.
AN at the Winston Weaver plant was exposed to moisture from a perpetually leaky roof and held in unsafe storage bins, NCDOL determined after interviews with employees who had worked there.
Those conditions had the potential to make the stored ammonium nitrate more volatile, increasing the risk of a destructive blast, the probe found.
‘It’s kind of complicated’
Extensive testing of the site by an environmental firm hired by Winston Weaver found the presence of fuel, “hot spots” of accumulated arsenic and high concentrations of other contaminants in soil and groundwater.
In a final assessment completed in September, Pennsylvania-based Montrose Engineering & Geology Inc. recommended that “additional soil remediation may be needed” to address high levels of arsenic on a portion of the site.
Long-term exposure to large amounts of arsenic, which occurs naturally in soil and many kinds of rock, can cause skin, lung, bladder, liver, kidney and prostate cancers, as well as coronary heart disease and other cardiovascular issues.
Montrose also suggested additional sampling to determine the depth of arsenic contamination.
In his Nov. 5 letter, Moore further instructed Winston Weaver to carry out testing and reporting that is “reasonable and necessary” to determine “any hazard posed by the site,” and develop and implement a cleanup plan “within reasonable time limits.”
“It’s kind of complicated because we’re looking at three different types of contaminants,” Moore said in the interview when asked about the future of the property. Those contaminants include compounds found in the fertilizer stored onsite for years, as well as heavy metals — including arsenic — and concentrations of fuel likely present below ground for decades before the fire.
DEQ also instructed the company to drill three new monitoring wells to those already in place to gauge the level of groundwater contamination.
“What we’re saying is the site’s not fully assessed but we don’t believe there’s a risk right now,” Moore explained.
Winston Weaver also will be tasked with removing a 400-foot gravel embankment that was hastily installed to prevent chemical-laden runoff as firefighters poured as much as 6,800 gallons of water per minute on the blaze.
Several storm drains under the berm and collection area remain sealed, and city of Winston-Salem officials have expressed concern that ash and contaminated soil could find their way into a section of the storm-water system that feeds into nearby Monarcas Creek.
DEQ instructed Winston Weaver to work with the city on removing the berm and safely reopening the drains.