NC0089621_More Information Requested_20180619

;n;* ROY COOPER
Governor
MICHAEL S.REGAN
Secretary
Water Resources a LINDA CULPEPPER
Environmental Quality Interim Director
June 19, 2018
Ms. Angela Walsh •
P.O. Box 576
Franklinton,NC 27525
Subject: Permit Application NC0089621
Novozymes WWTP
Franklin County
Dear Ms. Walsh:
Novozymes submitted a permit application to the Division on June 1, 2016 and subsequently has
submitted numerous documents for the Division's review. This letter summarizes outstanding
issues regarding the permit application and supporting documents.
Potassium
The Division reviewed the additional information submitted December 17, 2017 including the
review of USFWS "Estimating Potassium Concentrations for Freshwater Mussels, March 2017"
by Ramboll Environ. This evaluation points to deficiencies in the data and analysis provided by
the USFWS that supports evidence for the toxicity of potassium to freshwater mussels,but it
does not offer a solution to address the high potassium discharge.
Title 15A, section 02B .0208, of the North Carolina Administrative Code(NCAC) states, as part
of the NC aquatic life water quality standards,that "the concentration of toxic substances shall
not result in chronic toxicity." An evaluation of toxicity endpoints provided by EPA's
ECOTOXicology database(https://cfpub.epa.gov/ecotox/) shows that numerous species are
sensitive to potassium levels at or below the maximum concentration of 707 mg/L reported in the
Novozymes discharge. Examples of sensitivity include reported acute lethal concentration(LC50)
values of 53.2 mg/L for the freshwater scud Gammarus lacustris (De March et al., 1988), 415
mg/L for the water flea Daphnia magna (Bernot et al., 2005), and 720 mg/L for the channel
catfish Ictalurus punctatus (Waller et al., 1993). The high level of potassium known to occur in
the Novozymes discharge remains a concern as, combined with the low dilution potential of the
receiving stream,potentially toxic conditions for a variety of sensitive aquatic species may
result. Due to this concern,the Division is requesting that Novozymes perform testing to
evaluate the impact of its discharge to a variety of the sensitive freshwater species and to
freshwater mussels for the purpose of establishing a permit limitation protective of the receiving
stream Novozymes proposes to send its discharge. The Division recommends that Novozymes
Nothing Compares.:-
State of North Carolina I Environmental Quality
1611 Mail Service Center I Raleigh,North Carolina 27699-1611
919-707-9000 `

work with DWR's Standards Branch on the proposed study plan and acquire approval from the
Division before proceeding with testing. A complete report documenting all the test results
should be submitted to DWR for review. If the study is adequate, DWR will use this information
to establish potassium limits and toxicity testing needed in a proposed permit to protect the
receiving stream.
Engineering Alternative Analysis
The EAA should be updated to reflect the final project description and proposed treatment
system. The EAA should be submitted as one complete document and should reflect the final
proposed treatment system. The cost evaluation should be updated and should address potential
treatment to reduce salts in the effluent. Completion of the EAA may have to wait till the study
plan and limits are established as discussed above so actual treatment costs can be assessed.
Best Available Technology Analysis
The Division reviewed the Addendum to the BAT Analysis submitted on February 28, 2018. The
treatability study demonstrated that the wastewaters generated by the site are amenable to
treatment with advance nutrient removal technology. The Division has the following comments
on the study:
• Please clarify how was the data from the treatability study interpreted. For example, what
type of statistical analysis was performed to evaluate the data? The proposed limit was
derived from the reactor operated at 0.7 F/M ratio after the elimination of data from
several batches. Please explain why the eliminated data was not valid? Explain how the
laboratory data compares to the data collected by Dewberry.
• Please explain how the results were used to scale up the treatment system and provide the
updated design model for the new proposed treatment system.
• The Division does not agree that the surcharge cost imposed by municipalities is
equivalent to the cost of treatment to remove nitrogen used as comparison. A cost
comparison should include similar facilities and wastewaters. Cost is not the only criteria
evaluated to determine BAT.
• The BAT document should also be updated and compiled into one document. The
document should include the description of the existing operations,updated effluent data,
wastewater treatment technologies evaluated, cost analysis for evaluated technologies,
engineering models, treatability study, study results, statistical analysis and scale up of
the design. The BAT document should be updated, compiled and submitted as one
document.

Nitrogen Allocation
Note that Novozymes will have to acquire enough nitrogen allocations to cover Total Nitrogen
allocations in its NPDES permit. Please be aware when planning for the project that the existing
Nutrient rules in 15A NCAC 02B .0229 are under revision and will change in the coming years
resulting in increased allocation cost.
If Novozymes does not submit an updated BAT document and pursue a proposed potassium
study plan with the DWR Standards Branch, as described above,within the next 60 calendar
days [per 15A NCAC 2H.0107(b)],the project will be deactivated and withdrawn from our
review process and the documents recycled. If you wish to discuss the information above or if
you have any questions,please contact me at 919-807-6387 or email at
teresa.rodriguez@a,ncdenr.gov.
Sincerely,
Teresa Rodriguez
NPDES Complex Unit
Division of Water Resources/NCDEQ
cc: NPDES Files
Mike Poulios, Dewberry Engineers Inc.
2610 Wycliff Rd.
Raleigh,NC 27607
ec: Sarah McRae,USFWS
Connie Brower, Classifications, Standards and Rules Review Branch
Jeff Poupart, Water Quality Permitting