NC0025496_HWA AT approval_20220915

City of Lincolnton
Attn: Daniel Perry, Pretreatment Coordinator
P.O. Box 617
Lincolnton, NC27093
Email: [e-mail]
Subject: HWA-AT Approval
ProgramName:Lincolnton
NPDES Permit No NC0025496, 3.5 MGD
Class B Biosolids Permit No. WQ0002712
City of Lincolnton WWTP
Lincoln County, MRO
Dear Permittee:
The Municipal Unit of the Division of Water Resources has reviewed the Headworks Analysis
(HWA) and Allocation Table (AT) for the City of Lincolnton’s wastewater treatment plant
(WWTP) working under the NPDES Permit No NC0025496(effective on September 1, 2021).
The revised HWA wassubmittedon August 30, 2022, in response to the August 29, 2022, DWR’s
HWA Review Letter.

The Division concurs with the HWA calculations for all pollutants of concern, with the corrections
observations, and requests discussed below. The approved Maximum Allowable Headworks
Loadings (MAHLs), Maximum Allowable Industrial Loadings (MAILs), and the basis for these
values are found in the enclosed HWA and Allocation Table (AT) spreadsheet, which has the
updates and corrections highlighted. Please ensure to replace or update the POTW’s HWA AT
spreadsheets with this approved one.
1.HWA Corrections
a.The HWA Sheet included a new field for the POTW NPDES Design Flow (MGD), 6.0
MGD, this value is acceptable for the calculation of the Design Criteria. The current
POTW NPDES Permitted Flow (MGD), 3.5 MGD is used inthe ATcalculations.
2.HWA Observations and Requests
a.The literature Plant Removal Rate (%)for Bis (2-Ethylhexyl) Phthalate is acceptable at
this time. It is recommended that facilities which have detectable quantities of effluent
organics develop site-specific organic removal rates for the organics detected.
b.Thanks for providing additional information about the inclusion of Cerium and
Lanthanum in the HWA. Please include a note in the HWA narrative about those
elements in future HWA submittals

Next HWA Due date: The HWA approved today is based on DMR and LTMP data for the period
of March 2021 through February 2022. Unless conditions at the POTW change significantly and
thus warrant an earlier submittal (see Comprehensive Guide, Chapter 5, Section B), the POTW
must submit an updated site-specific HWA by November 30, 2026 (or after the reissue of the next
NPDES permit renewal/modification).

Regardless of this approval action today, within 180 days of the effective date of any
reissued/modified NPDES permit, the Permittee would be required to submit to the Division a
written technical evaluation of the need to revise local limits (i.e., an updated HWA or
documentation of why one is not needed) \[NPDES Permit Section D, 4.\]. This action may include
revising, updating, or adding to the list of Significant Industrial Users (SIUs) and/or modifying
SIU Industrial User Pretreatment Permit (IUP) limits. In addition, any executed Special Order of
Consent (SOC) conditions or requirements related to pretreatment or pretreatment program
updates must be complied with separately from this approval action.
Federal and State pretreatment regulations require the local delegated pretreatment program to
effectively control and document the discharge of wastewater from Significant/Categorical
Industrial Users to the POTW. It is the POTW’sresponsibility to ensure that these objectives are
consistently met.

Thank you for your continued support of the Pretreatment Program. If you have any questions or
comments, please contact the Pretreatment Coordinator Keyes \[[e-mail]\], or the
Unit Supervisor, Michael at \[[e-mail]\].

Sincerely,

for Richard E. Rogers Jr., Director
Division of Water Resources
dy/Lincolnton.25496_hwa_2022
Attachments:
Lincolnton.25496. HWA-AT (approved) (.xlsx and .pdf)
cc with attachments:
City of Lincolnton, Superintendent/ Donald Burkey
DWR - Morresville Regional Office – Pretreatment/Wes Bell
Municipal Unit File and Central Files (Laserfiche)