Enviva Southampton testing already completed?

Published 7:05 pm Friday, August 2, 2019

HAP tests from 2013, 2015 cited in permitting for North Carolina plant

[This is the fourth of a multi-part series. The fifth part investigates a claim that the DEQ required a pollution control device in Enviva Southampton’s 2012 permit, but removed this requirement the following year at the company’s request.]


While the Virginia Department of Environmental Quality appears to hold the opinion that Enviva is keeping up its end of the bargain, the Environmental Integrity Project — which sent a letter to Gov. Ralph Northam in April of last year alleging that Enviva Southampton was over-polluting — is still arguing for some type of enforcement action to be taken against the company. When the EIP learned of Enviva Southampton’s arrangement with the DEQ to delay the testing requirement for hazardous air pollutants (HAPs) and volatile organic compounds (VOCs) until after the plant’s proposed expansion, Patrick Anderson, the EIP’s legal counsel, sent another letter on behalf of the nonprofit organization and other environmental groups, this time to the director of the DEQ’s Air and Renewable Energy Division, Michael Dowd, on Nov. 5, 2018. This letter states, “Unfortunately, it now appears that DEQ has decided not to require those tests until after Enviva has radically modified the facility, meaning those tests will not reveal what is almost certainly a serious, years-long violation of the Clean Air Act and the facility’s permit … we therefore write to ask that DEQ bring an enforcement action based on existing credible evidence that Enviva Southampton constructed a major source of HAPs without undergoing the appropriate permitting and that the facility has likewise been violating permit limits on individual and total HAPs since it began operations… .”

Anderson’s Nov. 5 letter then claims Enviva conducted HAP emission testing on the wood dryer at the Southampton County facility in 2013 before the plant began operations and again in 2015, and therefore either knew or should have known about the alleged excess HAP emissions at that time. As proof of this claim, Anderson provided The Tidewater News with a copy of a July 18, 2018, letter from Michael Carbon, managing principal of the consulting firm Ramboll, to Kevin Godwin, a permit engineer with North Carolina’s DEQ, which was written on behalf of Enviva Pellets Hamlet LLC in regards to the planned expansion of Enviva’s Hamlet, North Carolina plant. This letter, according to Anderson, had been sent in response to the North Carolina DEQ’s July 6, 2018, request that Enviva identify what testing the company relied upon to develop its emission estimates for the Hamlet facility.

Attached to this letter is a list of the various Enviva plants the company tested when developing its emissions estimates. Included in this list are references to two tests conducted at the Southampton County facility — one on Dec. 3, 2013, and another on Dec. 1, 2015. Both tests, according to the list, were conducted on the Southampton facility’s wood dryer, and both tested for the following pollutants: acrolein, formaldehyde, methanol, phenol and propionaldehyde. The list of pollutants tested in 2015 also includes acetaldehyde. These six pollutants — as Tamera Thompson, manager of the DEQ’s Office of Air Permit Programs, previously confirmed — are the most prominent HAPs emitted by wood pellet manufacturing facilities.

Asked to describe the health effects of some of these HAPs, Dr. Dwight Flammia, a state public health toxicologist with the Virginia Department of Health, said acetaldehyde is a plant product and potential human carcinogen that is present in small amounts in fruits and bread. Its most likely health effect, when people are exposed to high concentrations in air, is eye, nose and throat irritation. Benzene, he said, is derived from petroleum. As such, it is found in car exhaust, but burning plant material also produces small amounts of benzene. At lower concentrations, it can cause drowsiness, confusion, dizziness and rapid heart rate. Exposure over a long period of time can cause anemia and is linked to leukemia. Very high concentrations can cause death. Formaldehyde, he said, is found in low levels in plants and animals, as well as many consumer products, including pressed wood, carpets and some personal care products. At low levels, formaldehyde can cause eye, nose and throat irritation. People exposed at their workplace to very high levels of formaldehyde over years have developed nose and throat cancers. Phenol and propionaldehyde are not considered to be carcinogens. However, short-term exposure to phenol can cause irritation to lungs, headaches and burning eyes. Higher concentrations over several weeks can cause heart, liver, kidney and lung damage, and even paralysis or death in some cases. Short-term exposure to propionaldenyde in studies on animals caused liver damage and increased blood pressure, but no studies about human health are available.

Anytime you go to the gas station, you’re breathing in benzene,” Flammia said, adding that health effects of each of these chemicals are “dependent on what the individual is exposed to, the length of duration, and route of exposure.”

That document [sent to the North Carolina DEQ] does not include the results [of the tests at the Southampton plant], nor have we ever been able to obtain the tests or the results,” Anderson said. “Last time I inquired with Virginia DEQ and North Carolina DEQ, around October 2018, neither agency had these tests nor the results, as Enviva never submitted the tests to the agencies.”

What the document does provide for each test at the Southampton facility is an operating production rate and percentage of softwood. For the 2013 test, an operating production rate of 62 oven-dried tons per hour (ODT/hr) is listed. For the 2015 test, 64.3 ODT/hr is listed. The percentage of softwood for each test is listed at 10 percent.

The operating production rate is the amount of wood being processed by the unit during testing,” Anderson explained. “Because the weight of wood depends on the amount of moisture it contains, and that in turn varies considerably throughout the manufacturing process, the industry uses ‘oven-dried ton,’ or ODT as a consistent baseline to measure weight. ODT is what the wood would weigh if all the moisture were removed.”

The production rate is important in the context of emissions, he explained, because typically emissions are estimated by multiplying the ODT by an emission factor. Emissions factors, he said, are estimates for the rate at which a particular pollutant is emitted, in terms of pounds per ODT. The attorney then provided the following example: if a plant produces 500,000 ODTs per year and the emission factor for, say, methanol, is 0.25 pounds per ODT, the plant can be estimated to emit 62.5 tons of methanol per year.

But without the actual results of the testing, the production rate itself is basically useless,” Anderson said. “One of the main problems with this industry is that there are no industry-standard emissions factors, unlike most other, more established industries … so the reason why so many plants in this industry have had issues with excess emissions is due to faulty (i.e. low) emission factors that are based on incorrect engineering assumptions or cherry picking from available emission factors.

For example, one problem we frequently see is that if there are, say, five emission factors available for a particular process, all based on real testing, companies will often select the lowest of the available factors in order to lower projected emissions, without adequate justification. Or they simply invent an emission factor based on ‘engineering judgement’ without a basis in testing, which often turns out to be low.”

According to Thompson, the 1990 amendments to the Clean Air Act task the federal Environmental Protection Agency (EPA) with setting industry-specific standards — either in terms of a numerical emissions limit or requiring a specific pollution control technology – for all pollution source categories that emit a major amount of the 187 HAPs the federal government currently regulates. The EPA, she said, has established 139 different maximum achievable control technology (MACT) standards — meaning best practices for pollution control — for both major and area (minor) sources, including sources as large as power plants and paper mills, and sources as small as dry cleaners. Thompson confirmed that at present, wood pellet manufacturing facilities are not included in the EPA’s list of pollution sources, and therefore, no federal MACT standard exists.

Since Enviva Southampton agreed to air quality permit limits to stay below the federal major source threshold, “DEQ applied the Virginia State Air Toxics regulations [when issuing air quality permits],” she said.

Thompson then confirmed that Enviva had tested the Southampton County facility in 2013 and again in 2015 for VOCs, particulate matter and nitrogen oxides, and had sent the results of those tests to the Virginia DEQ, but had not forwarded any test results for HAPs to the agency.

The VOC, particulate matter and nitrogen oxide test results, she said, indicated that the Southampton County plant was in full compliance with its air quality permit and federal standards for each of these pollutants, both in terms of its short-term limit measured in pounds per hour, and its annual limit measured in tons per year.

When asked why the DEQ requested additional VOC testing in June 2018, given that the 2013 and 2015 tests showed full compliance, Thompson explained that Enviva Southampton had only conducted testing on its wood dryer, as was required by their original permit. However, there are other sources of VOCs at the facility, such as the hammermills, she said, which Enviva’s original permit did not require to be tested.

The fact that Enviva Southampton showed neither the 2013 HAP test results, nor the 2015 results to the DEQ following its receipt of the agency’s June 2018 letter requiring testing, Anderson added, is what leads him to believe that these results likely showed something other than compliance with state and federal limits for HAPs.

Maria Moreno — a spokeswoman for Enviva Partners LP, the parent company of Enviva Southampton — when asked if Enviva had tested its Southampton County plant for HAP and VOC emissions in 2013 and again in 2015, did not answer “yes” or “no.” Nor did she provide any figures when asked for the results of these alleged tests in terms of tons per year. Moreno, rather, issued the following statement:

The Southampton plant has a valid air permit, which was issued in January 2015, and has been operating under and in compliance with all of its terms, including stack testing of the required air emissions. We performed the most recent stack testing in accordance with the requirements of the existing permit in April of this year and our stack compliance report was submitted to VA DEQ and is publicly available from VA DEQ. The test results are fully compliant with the permit and VA DEQ confirmed that in June.”

Thompson had previously confirmed that the April 2019 stack test data Enviva submitted for the Southampton County plant had only included results for particulate matter and nitrogen oxides. The April results did not include any figures for HAPs or VOCs, she said, and therefore, are not the same as the testing the DEQ requested in June 2018.

When asked if his firm had been able to obtain test results for any Enviva facilities that showed higher emissions than what the company had reported to its state environmental agency, Anderson said, “Not precisely, because few permits have required testing for HAPs. The closest instance is with regard to Enviva Sampson [in North Carolina], where Enviva eventually conceded that HAP emissions were much higher than originally estimated, but that plant was permitted as a major source for HAPs to begin with, so the higher emissions were not directly relevant to whether the facility was major or minor. That said, North Carolina did take action to require that plant to redo its major source HAP technology review and to install new pollution controls for HAPs.”