NC0038377_2021-08-30 SELC et al comments on Mayo permit modification_20211215

SOUTHERN ENVIRONMENTAL LAW CENTER
Telephone [phone]
VIA E-MAIL
601 WEST ROSEMARY STREET, SUITE 220 Facsimile 919-929-9421
CHAPEL HILL, NC 27516-2356
August 30, 2021
Sergei Chernikov
North Carolina Department of Environmental Quality
Wastewater Permitting
Attn: Mayo
1617 Mail Service Center
Raleigh, NC 27699-1617
[e-mail]
Re: Draft NPDES Permit NC00038377
Mayo Steam Electric Generating Plant
Dear Dr. Chernikov:
On behalf of the Sierra Club, Good Stewards of Rockingham, and the Dan Riverkeeper,
the Southern Environmental Law Center submits these comments on the proposed National
Pollutant Discharge Elimination System permit modification for Duke Energy's Mayo Steam
Electric Generating Plant, noticed for public comment by the North Carolina Department of
Environmental Quality.
The Department achieved tremendous progress for the Roanoke River basin when it
secured an agreement from Duke Energy to excavate its unlined, leaking coal ash pit at Mayo.
Moving the coal ash to a modern, lined landfill instead of a primitive pit will significantly reduce
groundwater and surface water pollution around Mayo. However, the agency must fulfill its
responsibility to oversee that landfill and its operation and ensure that it complies with the Clean
Water Act.
This draft permit modification does not fulfill this obligation. With this permit
modification, the Department plans to allow Duke Energy to flush as much as 50,000 gallons a
day —that is, 350,000 gallons per week and over 18 million gallons a year —of heavily polluted
coal ash landfill leachate through its new retention basin and into Mayo Lake with no treatment.
This leachate would presumably include the highly toxic FGD wastewater sent to the landfill to
condition ash, which DEQ itself notes has "elevated concentrations of metals and chloride." Fact
Sheet at 2.
Coal ash contains toxic substances, such as arsenic and mercury, which any water
flowing through the landfill collects and concentrates. DEQ's Reasonable Potential Analysis
makes clear that the leachate is highly polluted: adding it to the lined retention basin necessitates
new limits for arsenic, antimony, fluorides, chlorides, and barium to avoid violating water
quality standards. Fact Sheet at 4. But Congress has been clear that merely applying water
quality -based limitations is not enough: the agency cannot permit this wastestream without
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determining and requiring pollution limits based on the Best Available Technology, as the Clean
Water Act requires.
The Agency must establish Best Available Technology standards for Mayo's coal
ash landfill leachate.
As we have reminded the Department too many times to count, the Clean Water Act
requires that polluters use the best available technology economically achievable (BAT) to
control and if possible eliminate their discharge of pollutants. 33 U.S.C. § 1311(b)(2)(A). The
Act requires that water quality -based effluent limitations, like those DEQ has relied on in this
and other permits, serve as a supplemental, rather than the only, protection for lakes, rivers, and
streams. Congress made the Act "technology -forcing": technology -based effluent limitations
spur innovation in wastewater treatment and control and ensure progress toward the Act's goal of
eliminating the discharge of pollutants into navigable waters. Kennecott v. EPA, 780 F.2d 445,
448 (4th Cir. 1985); see also EPA v. Nat'l Crushed Stone Ass'n, 449 U.S. 64, 74 (1980).
Moreover, Best Available Technology limitations must "be based on the performance of the
single best -performing plant in an industrial field." Southwestern Electric Power Co. v. EPA,
920 F.3d 999, 1006 (5th Cir. 2019) (quoting Chem. Mfrs. Ass'n v. EPA, 870 F.2d 177, 226 (5th
Cir. 1989)). The Clean Water Act requires that permitting agencies "use the latest scientific
research and technology in setting effluent limits, pushing industries toward the goal of zero
discharge as quickly as possible." Kennecott, 780 F.2d at 448; see also NRDC v. EPA, 863 F.2d
1420, 1431 (9th Cir. 1988).
No national effluent limitation guidelines are in place setting BAT for coal ash landfill
leachate. In the 2015 Effluent Limitation Guidelines Rule for power plants ("ELG Rule"), EPA
attempted to rubber-stamp existing unlined coal ash settling lagoons as BAT for leachate,
providing no limits for toxic pollutants in that wastestream. Final Rule, Effluent Limitations
Guidelines and Standards for the Steam Electric Power Generating Point Source Category, 80
Fed. Reg. 67,837, 67,854 (Nov. 3, 2015).
But in 2019 the Fifth Circuit Court of Appeals rejected EPA's gambit, holding EPA
could not lawfully exempt leachate discharges from toxic limits and declare impoundments to be
the best available technology for leachate when the agency had repeatedly recognized that they
were outdated and ineffective. Sw. Elec. Power Co. v. EPA, 920 F.3d 999 (5th Cir. 2019). The
Fifth Circuit vacated this portion of the ELG Rule, stating:
[EPA's decision] is particularly inexplicable given the rule's recognition that
impoundments have proven "largely ineffective" at pollution control over the past
decades. And, as we have seen, it was the recognized shortcomings of
impoundments —shortcomings with respect to leachate discharges as well as other
wastestreams—that led the agency to revise the steam -electric effluent guidelines
in the first place.
Id. at 1025-26 (citations omitted).
Two years have passed since the Fifth Circuit's vacatur of the leachate portion of
the ELG Rule. EPA's 2020 rollback of the 2015 ELG Rule did nothing to address
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leachate pollution. Steam Electric Reconsideration Rule, 85 Fed. Reg 64,650, 64,654-55
(Oct. 13, 2020). Nor has EPA announced that it intends to address this in its forthcoming
rule to revise and hopefully strengthen power plant wastewater protections.1
In the absence of promulgated effluent limitation guidelines, the NPDES permit
writer must use best professional judgment to determine the BAT standard applicable to
the leachate discharges at Mayo. 33 U.S.C. § 1342(a)(1)(B); 40 C.F.R. § 125.3; 15A
N.C. Admin. Code 2H .0118. When applying best professional judgment, "[i]ndividual
judgments []take the place of uniform national guidelines, but the technology -based
standard remains the same." Tx. Oil & Gas Ass 'n v. EPA, 161 F.3d 923, 929 (5th Cir.
1998).
EPA has determined that what Duke Energy and DEQ propose here is absolutely illegal.
The exact same logic and deficient protections were included in a pollutant discharge permit
proposed by EPA for the Merrimack coal-fired plant in New Hampshire. Noting the decision in
Southwest Electric Power, EPA agreed that it had an obligation to set site -specific Best
Available Technology limitations. On the EPA's motion, the Environmental Appeals Board
agreed and remanded that portion of the proposed permit to correct this serious error. In re GSP
Merrimack LLC (NPDES Permit No. NH000 1465 Environmental Appeals Board, Appeals Nos.
05 & 06) (August 21, 2021) at 19.2 The Board approved EPA's plan to perform a site -specific
analysis. DEQ must do the same here.
Without nationally established effluent limitation guidelines for landfill leachate,
the agency's obligation is clear: DEQ must use its best professional judgment to set
technolojiv-based effluent limitations for leachate at Mayo. DEQ has not done this
analysis and this modification therefore violates the Clean Water Act.
DEQ must not rubber-stamp impoundments as BAT and should consider
membrane filtration.
In conducting the Clean Water Act -mandated analysis, the Department cannot reasonably
determine that the status quo of dumping leachate into an impoundment is the Best Available
Technology.
The Fifth Circuit stated that "everything the rule says about the record of impoundments
over the past three decades indicates that their performance in controlling discharges has been
distinctly poor." Sw. Elec. Power Co., 920 F.3d at 1018. Indeed, the record shows that
"impoundments are demonstrably ineffective at doing so and demonstrably inferior to other
available technologies." Id. at 1019.
1 2021 Supplemental Steam Electric Rulemaking,
https://www.epa.gov/eg/2021-supplemental-steam-electric-rulemaking.
2https://yosemite. epa. gov/OA/EAB_WEB_Docket.nsf/Filings%20By%20Appeal%20Number/C
B6DAB631 E28A9A4852587260066B9C0?OpenDocument.
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As it recognized, "the Supreme Court has explained that a BAT must achieve `reasonable
further progress' towards the Act's goal of eliminating pollution." Id. at 1006 (citing Nat'l
Crushed Stone, 449 U.S. at 75). EPA itself stated in the ELG Rule that impoundments "are
largely ineffective at controlling discharges of toxic pollutants and nutrients." 80 Fed. Reg.
67,840. And, for FGD wastewater, EPA found that declaring surface impoundments BAT
"would not result in reasonable further progress toward eliminating the toxic pollutants." Id. at
67,851.
EPA laid out the critical failings of impoundments in detail:
Pollutants that are present mostly in soluble (dissolved) form, such as selenium,
boron, and magnesium, are not effectively and reliably removed by gravity in
surface impoundments. For metals present in both soluble and particulate forms
(such as mercury), gravity settling in surface impoundments does not effectively
remove the dissolved fraction. Furthermore, the environment in some surface
impoundments can create chemical conditions (e.g., low pH) that convert
particulate forms of metals to soluble forms, which are not removed by the gravity
settling process.
Id. The Fifth Circuit held that "[t]hese conceded defects in impoundments are in critical tension
with EPA's choosing them as BAT for legacy wastewater." Sw. Elec. Power Co., 920 F.3d at
1017. The same would be true if DEQ made that mistake.
Rather, a membrane toxic pollution control technology is now available and effective for
such toxic pollution as leachate, and the Department cannot avoid requiring its installation at
Mayo.
Membrane filtration is obviously available, as EPA confirmed by using it for its
Voluntary Incentive Program limits in 2020, 85 Fed. Reg. 64,673, and reconfirmed in July 2021
when announcing its intention to reexamine the 2020 Rule to strengthen it: "treatment systems
using membranes continue to rapidly advance as an effective option for treating a wide variety of
industrial pollution, including from steam electric power plants."3 Moreover, EPA's 2020 ELG
Rule record demonstrates membrane technology is in use at three plants in China, and it has been
piloted by at least seven plants in the United States, including at Belews Creek. 84 Fed. Reg. at
64,632. The technology is also in use in other industries. EPA's site visit notes from its ELG
rulemaking reflect: "According to [Duke Energy], the paste encapsulation technology is well -
proven over the past several decades in the mining industry for tailings deposition and
underground backfill."4
3 EPA Announces Intent to Bolster Limits on Water Pollution from Power Plants (July 26, 2021)
https://www. epa.gov/newsreleases/epa-announces-intent-bolster-limits-water-pollution-power-
plants.
4 EPA, Notes from Site Visit to Duke Energy's Belews Creek Steam Station on December 13,
2017, Docket ID No. EPA-HQ-OW-2009-0819-7337 ("Belews Creek Site Visit Notes").
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Accordingly, membrane technology is "available," as Courts have interpreted the term
under the Clean Water Act, and should be used in the Wateree permit as BAT for leachate. At
the very least, the Department must do more than give its blessing to an impoundment system
that does not meaningfully control toxic pollution and must consider other treatment options.
Thank you for your consideration of these comments.
Sincerely,
cc: Bill Lane
Francisco Benzoni
Leslie Griffith
Staff Attorney
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