#159_2018_0321_AO_FINAL

To be attached to all inspection reports in-house only.
Laboratory Cert. #:
159
Laboratory Name:
Tarboro WWTP Laboratory
Inspection Type:
Municipal Maintenance
Inspector Name(s):
Anna Ostendorff and Beth Swanson
Inspection Date:
March 21 & 22, 2018
Date Forwarded for Initial
Review:
April 19, 2018
Initial Review by:
Jason Smith
Date Initial Review
Completed:
April 23, 2018
Cover Letter to use:
❑ Insp. Initial
❑Insp. No Finding
❑Corrected
(to use: rt click, properties, check)
® Insp. Reg
❑Insp. CP
❑Insp. Reg. Delay
Unit Supervisor/Chemist III:
Beth Swanson
Date Received:
April 30, 2018
Date Forwarded to Admin.:
May 15, 2018
Date Mailed:
May 16, 2016
Special Mailing Instructions:

May 16, 2018
159
Mr. Michael Allen
Tarboro WWTP Laboratory
P.O. Box 220
Tarboro, NC 27886-0220
ROY COOPER
MICHAE1.., S. REGAN
LINDA CULPEPPER
Subject: North Carolina Wastewater/Groundwater Laboratory Certification (NC WW/GW LC)
Maintenance Inspection
Dear Mr. Allen:
Enclosed is a report for the inspection performed on March 21 and 22, 2018 by Anna Ostendorff. I
apologize for the delay in getting this report to you. Where Finding(s) are cited in this report, a
response is required. Within thirty days of receipt, please supply this office with a written item for
item description of how these Finding(s) were corrected. Please describe the steps taken to prevent
recurrence and include an implementation date for each corrective action. If the Finding(s) cited in
the enclosed report are not corrected, enforcement actions may be recommended. For Certification
maintenance, your laboratory must continue to carry out the requirements set forth in 15A NCAC 2H
.0800.
A copy of the laboratory's Certified Parameter List at the time of the audit is attached. This list will
reflect any changes made during the audit. Copies of the checklists completed during the inspection
may be requested from this office. Thank you for your cooperation during the inspection. If you wish
to obtain an electronic copy of this report by email or if you have questions or need additional
information, please contact me at [phone] ext. 259.
Sincerely,
1
Beth Swanson
Technical Assistance & Compliance Specialist
Division of Water Resources
Attachment
cc: Anna Ostendorff, Dana Satterwhite
Water Sciences Section
NC Wastewater/Groundwater Laboratory Certification Branch
1623 Mall Service Center, Raleigh, North Carolina 27699-1623
Location: 4405 Reedy Creek Road, Raleigh, North Carolina 27607
Phom 919-733-39061 FAK 919-733-6241
Internet:

U Q91V
0*o]21k6'i:2*A0[QkiF
TYPE OF INSPECTION
/111 r7 f1 t771+'iir
LOCAL PERSON(S) CONTACTED:
I. INTRODUCTION:
Tarboro WWTP Laboratory
NC0020605
WQ0002047
Hwy 64/ Service Rd 268
Tarboro, NC 27886
159
March 21 & 22, 2018
Municipal Maintenance
Anna Ostendorff and Beth Swanson
Michael Allen and Kevin Peaden
This laboratory was inspected by representatives of the North Carolina Wastewater/Groundwater
Laboratory Certification (NC WW/GW LC) program to verify its compliance with the requirements
of 15A NCAC 2H .0800 for the analysis of compliance monitoring samples.
IL GENERAL COMMENTS:
The facility is neat and well organized and has all equipment necessary to perform the analyses.
Records are well organized and easy to retrieve. The laboratory has Quality Assurance
(QA)/Quality Control (QC) systems in place that exceed the minimum requirements. Additional
voluntary monitoring beyond the frequency required in the NC0020605 permit is performed and all
data is reported as required. Staff were forthcoming and seemed eager to adopt the necessary
changes.
All required Proficiency Testing (PT) Samples for the 2018 PT Calendar Year have not yet been
analyzed. The laboratory is reminded that results must be received by this office directly from the
vendor by September 30, 2018.
The laboratory submitted their QA and/or Standard Operating Procedures (SOP) document(s)
in advance of the inspection. These documents were reviewed and editorial and substantive
revision requirements and recommendations were made by this program outside of this formal
report process. Although subsequent revisions were not requested to be submitted, they must
be completed by May 31, 2019.

Page 2
#159 Tarboro yWVFP Laboratory
The laboratory is reminded that any time changes are made to laboratory procedures, the
laboratory must update the QA/SOP document(s) and inform relevant staff. Any changes made
in response to the pre -audit review or to Findings, Recommendations or Comments listed in this
report must be incorporated to insure the method is being performed as stated, references to
methods are accurate, and the QA and/or SOP document(s) is in agreement with each
approved practice, test, analysis, measurement, monitoring procedure or regulatory
requirement being used in the laboratory. In some instances, the laboratory may need to create
an SOP to document how new functions or policies will be implemented.
The laboratory is also reminded that SOPs are intended to describe procedures exactly as they
are to be performed. Use of the word "should" is not appropriate when describing requirements
(e.g., QC frequency, acceptance criteria, etc.). Evaluate all SOPs for the proper use of the word
"should".
Laboratory Fortified Matrix (LFM) and Laboratory Fortified Matrix Duplicate (LFMD) are also
known as Matrix Spike (MS) and Matrix Spike Duplicate (MSD) and may be used
interchangeably in this report.
Requirements that reference 15A NCAC 2H .0805 (a) (7) (A), stating "All analytical data pertinent
to each certified analysis must be filed in an orderly manner so as to be readily available for
inspection upon request", are intended to be a requirement to document information pertinent to
reconstructing final results and demonstrating method compliance. Use of this requirement is not
intended to imply that existing records are not adequately maintained unless the Finding speaks
directly to that.
Contracted analyses are performed by Environment 1, Inc. (Certification # 10).
Approved Procedure documents for the analysis of the facility's currently certified Field
Parameters were provided at the time of the inspection.
III. FINDINGS, REQUIREMENTS, COMMENTS AND RECOMMENDATIONS:
Documentation
A. Finding: The units of measure are not consistently documented on the benchsheets.
Requirement: All laboratories must use printed laboratory bench worksheets that include
a space to enter the signature or initials of the analyst, date of analyses, sample
identification, volume of sample analyzed, value from the measurement system, factor and
final value to be reported and each item must be recorded each time samples are
analyzed. Ref: 15A NCAC 2H .0805 (a) (7) (H).
Comment: The BOD benchsheet "seed correction" column heading units were
documented as mg instead of mg/L. The refrigerator and incubator temperature logs do
not specify units of measure.
B. Finding: The laboratory benchsheet for Field Parameters was lacking pertinent data:
meter calibration time.
Requirement: All analytical data pertinent to each certified analysis must be filed in an
orderly -manner so as to be readily available for inspection upon request. Ref: 15A NCAC
2H .0805 (a) (7) (A).

Page 3
#159 Tarboro WWTP Laboratory
Requirement: The following must be documented in indelible ink whenever sample
analysis is performed: meter calibration and meter calibration time(s). Ref: NC WW/GW
LC Approved Procedure for the Analysis of Total Residual Chlorine, NC WW/GW LC
Approved Procedure for the Analysis of Dissolved Oxygen and NC WW/GW LC
Approved Procedure for the Analysis of pH.
Comment: This applies to Total Residual Chlorine (TRC), Dissolved Oxygen (DO) and
pH.
C. Finding: The laboratory benchsheet was lacking pertinent data: instrument identification.
Requirement: All analytical data pertinent to each certified analysis must be filed in an
orderly manner so as to be readily available for inspection upon request. Ref: 15A NCAC
2H .0805 (a) (7) (A).
Requirement: The following must be documented in indelible ink whenever sample
analysis is performed: Instrument identification (serial number preferred). Ref: NC
WW/GW LC Approved Procedure for the Analysis of Total Residual Chlorine, NC
WW/GW LC Approved Procedure for the Analysis of Dissolved Oxygen and NC WW/GW
LC Approved Procedure for the Analysis of pH.
Comment: This applies to TRC, DO and pH.
D. Finding: The laboratory needs to increase the traceability documentation of purchased
materials and reagents.
Requirement: All chemicals, reagents, standards and consumables used by the
laboratory must have the following information documented: Date received, Date Opened
(in use), Vendor, Lot Number, and Expiration Date (where specified). Consumable
materials such as pH buffers, lots of pre -made standards and/or media, solids and
bacteria filters, etc. are included in this requirement. Ref: NC WW/GW LC Policy.
Requirement: Supporting records shall be maintained as evidence that these practices
are being effectively carried out. All analytical records must be available for a period of five
years. Ref: 15A NCAC 2H .0805 (a) (7) and (a) (7) (G).
Comment: The laboratory maintains a reagent preparation log that documents the lot
numbers, vendor and expiration date of all parent materials. Consumable materials that
are not used in the preparation of reagents or solutions, such as pH buffers and TSS
filters, are not documented.
E. Finding: The laboratory was not documenting their use of heat -indicating tape. This is
considered pertinent data.
Requirement: Use heat -indicating tape to identify supplies and materials that have been
sterilized. Ref: Standard Methods 9020 B-2005. (4) (h).
Requirement: Each laboratory shall develop and maintain a document outlining the
analytical quality control practices used for the parameters included in their certification.
Supporting records shall be maintained as evidence that these practices are being
effectively carried out. Ref: 15A NCAC 2H .0805 (a) (7).

Page 4
#159 Tarboro WWTP Laboratory
Requirement: All analytical data pertinent to each certified analysis must be filed in an
orderly manner so as to be readily available for inspection upon request. Ref: 15A NCAC
2H .0805 (a) (7) (A).
General Laboratory
F. Finding: The laboratory is analyzing compliance samples and reporting data for Fecal
Coliform in sludge samples without certification by NC WW/GW LC.
Requirement: Municipal and Industrial Laboratories are required to obtain certification for
parameters which will be reported to the State to comply with State surface water
monitoring, groundwater, and pretreatment Rules. Ref: 15A NCAC 2H .0804 (a).
Comment: The laboratory was analyzing Fecal Coliform by membrane filtration (i.e., SM
9222 D-1997) in Class B sludge samples for land application. The laboratory was unaware
separate certification is required for non -aqueous samples under the Code of Federal
Regulations, Title 40, part 503. The laboratory must contract out future sludge analyses or
obtain certification for the non -aqueous membrane filtration method (i.e., SM 9222 D-2006
(MF) 24hr 503).
Quality Control
G. Finding: Composite samples for Ammonia and COD are not being chemically preserved
toapH<2.
Requirement: Preservation: Cool, :56 °C, H2SO4 to pH <2. Ref: Code of Federal
Regulations, Title 40, Part 136; Federal Register Vol. 82, No. 165, August 28, 2017;
Table II.
Requirement: For a composite sample collected with an automated sampler (e.g.,
using a 24-hour composite sampler; see 40 CFR 122.21 (g) (7) (i) or 40 CFR Part 403,
Appendix E), refrigerate the sample at 56 °C during collection unless specified otherwise
in this Table II or in the method(s). For a composite sample to be split into separate
aliquots for preservation and/or analysis, maintain the sample at :56 °C, unless specified
otherwise in this Table II or in the method(s), until collection, splitting, and preservation
is completed. Add the preservative to the sample container prior to sample collection
when the preservative will not compromise the integrity of a grab sample, a composite
sample, or an aliquot split from a composite sample; otherwise, preserve the grab
sample, composite sample, or aliquot split from a composite sample within 15 minutes
of collection. Ref: Code of Federal Regulations, Title 40, Part 136; Federal Register Vol.
82, No. 165, August 28, 2017; Table ll, Footnote 2.
Requirement: A record of date collected, time collected, sample collector, and use of
proper preservatives must be maintained. Each sample must clearly indicate the State of
North Carolina collection site on all record transcriptions. Ref: 15 NCAC 2H .0805 (a) (7)
(M).
Comment: Chemical preservation of the samples must be verified with a meter or test
strips and documented.
H. Finding: The laboratory is not monitoring and documenting pretreatment sample
temperatures upon receipt in the laboratory.

Page 5
#159 Tarboro yW TP Laboratory
Requirement: A record of date collected, time collected, sample collector, and use of
proper preservatives must be maintained. Each sample must clearly indicate the State of
North Carolina collection site on all record transcriptions. Ref: 15 NCAC 2H .0805 (a) (7)
(M).
Requirement: Basic documentation requirements to verify that sample preservation and
hold time requirements are met include: Preservation status; temperature and chemical
preservative(s) used (i.e., name of preservative, pH<2, pH>9, etc., where pH is not
adequately adjusted document the measured pH). Ref: NC WW/GW LC Policy.
Comment: Pretreatment samples are placed on ice and transported in a cooler to the
Tarboro WWTP Laboratory for analysis, but the sample temperatures are not checked or
documented upon arrival at the laboratory. If transport times are not long enough for
sample temperatures to reach <_6 °C, the laboratory may measure and document sample
temperatures at collection and upon arrival at the laboratory to document a downward
trend.
Finding: For chemicals/reagents/consumables that do not have an expiration date, the
laboratory has not established a policy for assigning expiration dates.
Requirement: Adherence to manufacturer expiration dates is required.
Chemicals/reagents/ consumables exceeding the expiration date can no longer be
considered reliable. If the expiration is only listed as a month and year (with no specific day
of the month), the last day of the month will be considered the actual date of expiration.
Monitor materials for changes in appearance or consistency. Any changes may indicate
potential contamination and the item should be discarded, even if the expiration date is not
exceeded. If no expiration date is given, the laboratory must have a policy for assigning an
expiration date. If no date received or expiration date can be determined, the item should
be discarded. Ref: NC WW/GW LC Policy.
J. Finding: Precision of sample duplicates for COD is not consistently evaluated to
demonstrate the analytical process is in control and the established acceptance criterion is
met.
Requirement: Each laboratory shall develop and maintain a document outlining the
analytical quality control practices used for the parameters included in their certification.
Supporting records shall be maintained as evidence that these practices are being
effectively carried out. Ref: 15A NCAC 2H .0805 (a) (7).
Comment: The precision and accuracy of QC results must be documented and evaluated
against the prescribed acceptance criteria to demonstrate that the analytical process is in
control. Any samples associated with QC not meeting the criteria must be reanalyzed if
possible. If this is not possible, the data must be flagged on the laboratory reports and
electronic Discharge Monitoring Reports (eDMR) as all quality control requirements not
met and giving a brief description of the QC exceedance that occurred.
K. Finding: Data that does not meet all QC requirements is not always qualified on the
eDMR.
Requirement: When QC failures occur, the laboratory must attempt to determine the
source of the problem and must apply corrective action. If data qualifiers are used to
qualify samples not meeting QC requirements, the data may not be useable for the
intended purposes. A notation must be made on the electronic Discharge Monitoring

Page 6
#159 Tarboro WWTP Laboratory
Report (eDMR) form, when any required sample quality control does not meet specified
criteria, and another sample cannot be obtained. Ref: NC WW/GW LC Policy.
Comment: This was only observed for Suspended Residue sample duplicates, which had
low Suspended Residue values and were evaluated against a 30% RPD.
Recommendation: It is recommended that the laboratory implement tiered acceptance
criteria for evaluating duplicates. For example, the acceptance criterion for low-level
samples could be ± mg/L, while high-level samples could be %RPD.
Proficiency Testing
L. Finding: PT Samples have not been distributed among all analysts from year to year.
Requirement: Laboratories shall also ensure that, from year to year, PT Samples are
equally distributed among personnel trained and qualified for the relevant tests and
instrumentation (when more than one instrument is used for routine Compliance Sample
analyses), that represents the routine operation of the work group at the time the PT
Sample analysis is conducted. Ref: Proficiency Testing Requirements, May 31, 2017,
Revision 2.0.
M. Finding: The laboratory does not have a documented plan for PT procedures.
Requirement: Each laboratory shall develop and maintain a document outlining the
analytical quality control practices used for the parameters included in their certification.
Supporting records shall be maintained as evidence that these practices are being
effectively carried out. Ref: 15A NCAC 2H .0805 (a) (7).
Requirement: Laboratories must have a documented plan (this is usually detailed in the
laboratory's Quality Assurance Manual or may be a separate SOP) of how they intend to
cover the applicable program requirements for Proficiency Testing per their scope of
accreditation. This plan shall cover any commercially available PT Samples and any inter -
laboratory organized studies, as applicable. The laboratory must also be able to explain
when PT Sample analysis is not possible for certain methods and provide a description of
what the laboratory is doing in lieu of Proficiency Testing. This shall be detailed in the plan.
The plan must also address the laboratory's process for submission of PT results and
related Corrective Action Reports (CARs). Ref: Proficiency Testing Requirements, May 31,
2017, Revision 2.0.
Requirement: SOPs must address situations where the instructions from the Accredited
PT Provider for the preparation, analysis or result calculations would constitute a deviation
from the laboratory's routine procedure. Examples of this may include how low-level
samples will be analyzed, including concentration of the sample or adjustment of the
normality of a titrant. These instructions shall be followed when the concentration of a PT
sample falls below the range of their routine analytical method. Instructions shall also be
included in the laboratory's SOP for how high-level samples will be analyzed, including
preparation of multiple dilutions of the sample. These instructions will be followed when the
concentration of a PT falls above the range of their routine analytical method. Ref:
Proficiency Testing Requirements, May 31, 2017, Revision 2.0.
N. Finding: The laboratory is not documenting the preparation of PT Samples.

Page 7
#159 Tarboro WWTP Laboratory
Requirement: PT Samples received as ampules are diluted according to the Accredited
PT Sample Provider's instructions. It is important to remember to document the
preparation of PT Samples in a traceable log or other traceable format. The diluted PT
Sample then becomes a routine Compliance Sample and is added to a routine sample
batch for analysis. No documentation is needed for whole volume PT Samples which
require no preparation (e.g., pH), but it is recommended that the instructions be
maintained. Ref: Proficiency Testing Requirements, May 31, 2017, Revision 2.0.
Comment: Dating and initialing the instruction sheet for each prepared PT Sample would
satisfy the documentation requirement.
Bacteria — Coliform, Fecal — Standards Methods, 9222 D-1997 (MF) (Aqueous)
Comment: The laboratory was in the process of gaining certification for the IDEXX Colilert-18®
method for the analysis of Fecal Coliform at the time of the inspection. The SM 9222 D-1997 (MF)
method was audited but the laboratory is no longer certified for the method. This change was
effective March 29, 2018.
®. Finding: The time sample filtration begins was not recorded on the benchsheet to show
that no more than 30 minutes had passed before filters were placed into the incubator.
This is considered pertinent data.
Requirement: Place all prepared cultures in the water bath within 30 min after filtration.
Ref: Standard Methods, 9222 D-2006. (2) (d).
Requirement: All analytical data pertinent to each certified analysis must be filed in an
orderly manner so as to be readily available for inspection upon request. Ref: 15 NCAC
21-1.0805 (a) (7) (A).
P. Finding: Compliance sample results were not always calculated and reported correctly.
Requirement: Countable Membranes with 20-60 Blue Colonies: Calculate the fecal
coliform results from membrane filters within the ideal counting range of 20-60 blue
colonies using the general formula:
Number of colonies counted x 100 = Fecal coliform colonies per 100 ml
volume of sample filtered in ml
If more than one filter (including a 100-mL sample volume) has a count in the acceptable
range, calculate the values in counts/100 mL for each filter in the countable range and
average.
Ref: NC WW/GW LC Policy
Requirement: Countable Membranes with less than 20 Blue Colonies: If all counts are
below the lower limit (20) of the ideal counting range:
(a) Select the count most nearly acceptable and compute the count using the general
formula. Report the count as an Estimated Count per 100 mL: or
(b) Total the counts on all filters and report as number per 100 mL. For example, if 50,
25, and 10 mL portions were examined and counts were 15, 6, and 0 coliform

Page 8
#159 Tarboro VW TP Laboratory
colonies respectively, calculate results as follows and report the count as 25
colonies per 100 mL.
(15 + 6 + 0) counts x 100 = 25 colonies per 100 mL
50+25+10mL
Ref: NC WW/GW LC Policy
Comment: When a sample batch produced plate counts with both 20 — 60 colonies and
less than 20 colonies, the laboratory was calculating and reporting results using option (b).
This method of calculating and reporting results is only applicable when all plates produce
less than 20 blue colonies.
Comment: When all plates produce less than 20 blue colonies, most laboratories elect to
calculate and report results using option (b) as opposed to option (a).
Q. Finding: Sample bottle sterility was not verified.
Requirement: Minimally test for sterility one sample bottle per batch sterilized in the
laboratory, or at a set percentage such as 1 to 4%. This is performed by adding sterile
dilution/rinse water to the bottle after sterilization and then subsequently analyzing it as a
sample. Document results. If sample bottles or bags are purchased pre -sterilized,
verification of sterilization is not required if the laboratory maintains copies of the
Certificate of Analysis from the vendor. Ref: NC WW/GW LC Policy.
Comment: This requirement also applies to sample bottles that are reused for analysis
with the IDEXX Colilert-18® method. If pre -sterilized disposable bottles are used, retaining
the vendor's Certificate of Analysis will satisfy this requirement.
R. Finding: Plate comparison counts were not being performed.
Requirement: For routine performance evaluation, repeat counts on one or more positive
samples at least monthly, record results, and compare the counts with those of other
analysts testing the same samples. Replicate counts for the same analyst should agree
within 5% (within analyst repeatability of counting) and those between analysts should
agree within 10% (between analysts reproducibility of counting). If they do not agree,
initiate investigation and any necessary corrective action. Ref: Standard Methods, 9020 B-
2005. (9) (a).
BOD —Standard Methods, 5210 B-2011 (Hach 10360-2011, Rev. 1.2) (LDO)
S. Finding: Seed controls with less than 2.0 mg/L DO depletion are sometimes used for the
seed correction calculation.
Requirement: For the ratio method, divide the DO depletion by the volume of seed in
milliliters for each seed control bottle having a 2.0 mg/L depletion and greater than 1.0
mg/L minimum residual DO and average the results. Ref: Standard Methods, 5210 B-
2011. (6) (d).
T. Finding: Extra nutrient, mineral, and buffer solutions are not added to the Biochemical
Oxygen Demand (BOD) bottles containing more than 67% (i.e., > 201 mL) sample.

Page 9
#159 Tarboro WWTP Laboratory
Requirement: When a bottle contains more than 67% of the sample after dilution,
nutrients may be limited in the diluted sample and subsequently reduce biological activity.
In such samples, add the nutrient, mineral, and buffer solutions (3a through e) directly to
diluted sample at a rate of 1 mUL (0.30 mL/300-mL bottle) or use commercially -prepared
solutions designed to dose the appropriate bottle size. Ref: Standard Methods, 5210 B-
2011. (5) (c) (2).
U. Finding: Samples with less than 2.0 mg/L DO depletion are sometimes used for
calculating the final BOD results.
Requirement: Only bottles, including seed controls, giving a minimum DO depletion of 2.0
mg/L and a residual DO of at least 1.0 mg/L after 5 d of incubation are considered to
produce valid data, because at least 2.0 mg oxygen uptake/L is required to give a
meaningful measure of oxygen uptake and at least 1.0 mg/L must remain throughout the
test to ensure that insufficient DO does not affect the rate of oxidation of waste
constituents. Ref: Standard Methods, 5210 B-2011. (6) (a).
Requirement: Average the test results for all qualified bottles within each dilution series.
Ref: Standard Methods, 5210 B-2011. (7) (b).
Recommendation: It is recommended a system of peer review be implemented to ensure
calculations are properly performed and the data is reported correctly.
Chlorine, Total Residual — Standard Methods, 4500 Cl G-2011 (Aqueous)
Recommendation: It is recommended the laboratory verify the factory -set calibration curve
annually using a 400 tag/L standard as the highest standard concentration. Currently, the highest
standard concentration verified is 200 tag/L. PT Sample concentrations can exceed 300 tag/L,
though all observed historical PT Samples analyzed by the laboratory were bracketed. Increasing
the highest standard concentration to 400 tag/L will ensure future PT Sample concentrations are
bracketed.
V. Finding: The laboratory is not analyzing a Reagent Blank.
Requirement: If preparing standards, analyzing a PT Sample or analyzing diluted
samples, a Reagent Blank is required. Ref: NC WW/GW LC Approved Procedure for the
Analysis of Total Residual Chlorine.
Comment: The laboratory prepares an aqueous standard to verify instrument calibration
each day of analysis. A reagent blank must be analyzed each day to document there is no
interference from the reagent water used to prepare the standard. This must also be done
with the annual 5-standard factory -set calibration curve verification.
COD — Standard Methods, 5220 D-2011 (Aqueous)
Comment: Because the laboratory uses a spectrophotometer with a factory -set calibration curve,
all standards used in the preparation of QC elements are from a source independent of what was
used to generate the calibration curve and are therefore considered second source. The
laboratory analyzes an additional second source standard, which is not necessary and may be
eliminated.

Page 10
#159 Tarboro VWVfP Laboratory
Comment: The preservative that is added to compliance samples must also be added to the
digested blank and Laboratory Fortified Blank (LFB) once the laboratory begins to chemically
preserve samples.
W. Finding: The laboratory was not using an undigested blank as the reference solution for
evaluating the digested blank for samples analyzed at 600 nm.
Requirement: At 600 nm, use an undigested blank as reference solution. Analyze a
digested blank to confirm good analytical reagents and to determine the blank COD;
subtract blank COD from sample COD. Alternately, use digested blank as the reference
solution once it is established that the blank has a low COD. Ref: Standard Methods, 5220
D-2011. (4) (b).
Comment: The laboratory uses a digested blank as the reference solution, but has not
evaluated the digested blank against the undigested blank to establish the digested blank
has a low COD.
X. Finding: The laboratory was not using reagent water as the reference solution for
samples analyzed at 420 nm.
Requirement: At 420 nm, use reagent water as a reference solution. Measure all
samples, blanks, and standards against this solution. The absorption measurement of an
undigested blank containing dichromate, with reagent water replacing sample, will give
initial dichromate absorption. Any digested sample, blank, or standard that has a COD
value will give lower absorbance because of the decrease in dichromate ion. Ref:
Standard Methods, 5220 D-2011. (4) (b).
Comment: The laboratory currently uses a digested blank as the reference solution for
analyzing samples. The initial dichromate absorption must be determined by zeroing the
meter with reagent water and analyzing the undigested blank. The digested blank is then
analyzed and that value is subtracted from sample and standard measurements to obtain
the final result.
Y. Finding: The laboratory has not established an acceptance criterion for the calibration
curve verification.
Requirement: Each laboratory shall develop and maintain a document outlining the
analytical quality control practices used for the parameters included in their certification.
Supporting records shall be maintained as evidence that these practices are being
effectively carried out. Ref: 15A NCAC 2H .0805 (a) (7).
Comment: The laboratory must set an acceptance criterion for the % recovery of the
calibration standards when the calibration curve is verified. The acceptance criterion may
not exceed 15%.
Z. Finding: A reporting limit verification standard is not analyzed initially and at least
quarterly for the low range curve.
Requirement: Verify quantitation at the Minimum Reporting Level (MRL) initially and at
least quarterly (preferably daily) by analyzing a QC sample (subjected to all sample -
preparation steps) spiked at a level 1 to 2 times the MRL. A successful verification meets
the method's or laboratory's accuracy requirements at the MRL. Laboratories must define

Page 11
#159 Tarboro WWTP Laboratory
acceptance criteria for the operational range, including the MRL, in their QA
documentation. Ref: Standards Methods, 5020 B-2010. (1) (c).
Comment: A reporting limit verification standard is analyzed for the high range curve each
day compliance samples are analyzed.
AA. Finding: A calibration blank and calibration verification standard (mid -range) are not
analyzed at the end of the sample group.
Requirement: Verify calibration by periodically analyzing a calibration standard and
calibration blank during a run — typically, after each batch of ten samples and at the end of
the run. Ref: SM 5020 B-2010. (2) (b).
Requirement: The calibration blank and calibration verification standard (mid -range) must
be analyzed initially (i.e., prior to sample analysis), after every tenth sample and at the end
of each sample group to check for carry over and calibration drift. If either fall outside
established quality control acceptance criteria, corrective action must be taken (e.g.,
repeating sample determinations since the last acceptable calibration verification,
repeating the initial calibration, etc.). Ref: NC WW/GW LC Policy.
BB. Finding: The laboratory is not analyzing an LFM.
Requirement: When appropriate for the analyte (Table 5020:1), include at least one
LFM/LFMD daily or with each batch of 20 or fewer samples. To prepare an LFM, add a
known concentration of analytes (ideally from a second source) to a randomly selected
routine sample without increasing its volume by more than 5%. Ref: SM 5020 B-2010,
Table 5020:1 and (2) (g).
Comment: For spike solution volumes that constitute >1 % of the total sample volume, the
percent recovery calculation must be volume adjusted.
Recommendation: Preparing the LFM in the vial without diluting the sample by more than
5% is difficult since only 2 mL of additional volume can be added to the digestion vials. It is
recommended that the LFM be prepared in a volumetric flask using a larger sample
volume and 2 mL of the prepared LFM be transferred to the vial.
CC. Finding: The laboratory is not analyzing a sample duplicate for the high -range samples.
Requirement: When appropriate for the analyte (Table 5020:1), include at least one
LFM/LFMD daily or with each batch of 20 or fewer samples. To prepare an LFM, add a
known concentration of analytes (ideally from a second source) to a randomly selected
routine sample without increasing its volume by more than 5%. Ref: SM 5020 B-2010,
Table 5020:1 and (2) (g).
Comment: The laboratory may analyze either an LFMD or a sample duplicate to fulfil this
requirement.
Comment: Only one compliance sample is analyzed using the high -range test kit. The
laboratory analyzes a sample duplicate with each batch for low -range samples.
Nitrogen, Ammonia — Standard Methods, 4500 NH3 D-2011 (Aqueous)

Page 12
#159 Tarboro WVVfP Laboratory
Comment: The preservative that is added to compliance samples must also be added to the
Method Blank (MB) and Laboratory Fortified Blank (LFB) once the laboratory begins to chemically
preserve samples.
DD. Finding: The laboratory does not document the slope of the meter calibration in units of
mV.
Requirement: All analytical data pertinent to each certified analysis must be filed in an
orderly manner so as to be readily available for inspection upon request. Ref: 15A NCAC
2H .0805 (a) (7) (A).
Requirement: If the electrode is functioning properly a tenfold change of NH3-N
concentration produces a potential change of about 59 mV. Ref: SM 4500 NH3 D-2011.
(4) (c).
Comment: The laboratory documents the slope of the meter calibration in percent
efficiency.
EE. Finding: The laboratory is not randomly selecting samples to fortify and duplicate.
Requirement: When appropriate for the analyte (Table 4020:1), include at least one
LFM/LFMD daily or with each batch of 20 or fewer samples. To prepare an LFM, add a
known concentration of analytes (ideally from a second source) to a randomly selected
routine sample without increasing its volume by more than 5%. Ref: SM 4020 B-2011,
Table 4020:1 and (2) (g).
Comment: The laboratory routinely fortifies and duplicates the Effluent sample only.
FF. Finding: The laboratory is not adjusting the sample concentration in the percent recovery
calculation when the spike volume is >1 % of the total sample volume.
Requirement: The volume of spike solution used in MS preparation must in all cases be
<_ 5% of the total MS volume. It is preferable that the spike solution constitutes <_ 1% of
the total MS volume so that the MS can be considered a whole volume sample with no
adjustment (i.e., volume correction) by calculation necessary. If the spike solution
volume constitutes >1 % of the total sample volume, the sample concentration must be
adjusted by calculation. Ref: NC WW/GW LC Policy.
Comment: The spike solution volume constitutes 2.5% of the total volume for the
LFM/LFMD. The laboratory must either use the volume adjusted calculation or reduce the
volume of spiking solution added to _< 1 % of the total sample volume.
pH — Standard Methods, 4500 H+ B-2011 (Aqueous)
GG. Finding: The laboratory is not analyzing a post -analysis check standard buffer when
analyses are performed at multiple locations.
Requirement: When performing analyses at multiple sample sites, a post -analysis
calibration verification using the check standard buffer must be analyzed at the end of the
run. The post -analysis check standard buffer(s) must read within ±0.1 S.U. or corrective
actions must be taken. If recalibration is necessary, all samples analyzed since the last
acceptable calibration verification must be reanalyzed, if possible. If samples cannot be

Page 13
#159 Tarboro WWTP Laboratory
reanalyzed, the data must be qualified. Ref: NC WW/GW LC Approved Procedure for the
Analysis of pH.
Residue, Suspended — Standard Methods, 2540 D-2011 (Aqueous)
Recommendation: It is recommended that the laboratory use a 0.1 g weight to check the
balance each day of use since it is more representative of sample weights. Currently, the balance
is checked with a 50-g weight each day of use.
HH. Finding: Sample filters are not being washed after sample transfer.
Requirement: Wash filter with three successive 10-mL volumes of reagent -grade water,
allowing complete drainage between washings, and continue suction for about 3 min after
filtration is complete. Samples with high dissolved solids may require additional washings.
Ref: Standard Methods, 2540 D-2011. (3) (c).
II. Finding: Samples chosen for duplicate analyses are not randomly selected.
Requirement: When appropriate (Table 2020:1), randomly select routine samples to be
analyzed twice. Ref: Standard Methods, 2020 B-2010. (2) (f).
Comment: The laboratory routinely duplicates the Effluent samples.
Bacteria — Coliform, Fecal — Standards Methods, 9222 D-1997 (Aqueous)
Nitrogen, Ammonia — Standard Methods, 4500 NH3 D-2011 (Aqueous)
JJ. Finding: Samples are not consistently checked for the presence of residual chlorine.
Requirement: Except where noted in this Table II and the method for the parameter,
preserve each grab sample within 15 minutes of collection. For a composite sample
collected with an automated sample (e.g., using a 24-hour composite sample; see 40 CFR
122.21 (g)(7)(i) or 40 CFR Part 403, Appendix E), refrigerate the sample at <_6°C during
collection unless specified otherwise in this Table II or in the method(s). For a composite
sample to be split into separate aliquots for preservation and/or analysis, maintain the
sample at <_6°C, unless specified otherwise in this Table II or in the method(s), until
collection, splitting, and preservation is completed. Add the preservative to the sample
container prior to sample collection when the preservative will not compromise the integrity
of a grab sample, a composite sample, or aliquot split from a composite sample within 15
minutes of collection. If a composite measurement is required but a composite sample
would compromise sample integrity, individual grab samples must be collected at
prescribed time intervals (e.g., 4 samples over the course of a day, at 6-hour intervals).
Ref: Code of Federal Regulations, Title 40, Part 136; Federal Register Vol. 88, No. 165,
August 28, 2017; Table 11, Footnote 2.
Requirement: Preservation: Coliform, total
Na2S2O3. Ref: Code of Federal Regulations,
No. 165, August 28, 2017; Table II.
fecal, and E. coli: Cool, <10 °C, 0.008%
Title 40, Part 136; Federal Register Vol. 82,
Requirement: Residual Chlorine reacts with ammonia; remove by sample pretreatment. If
a sample is likely to contain residual chlorine, immediately upon collection, treat with
dechlorinating agent as in 4500-NH3.B.3d. Ref: Standard Methods, 4500 NH3 A-2011. (2).

Page 14
#159 Tarboro WWTP Laboratory
Requirement: Dechlorinating agents used at the time of sampling must be documented to
have been effective upon receipt in the laboratory. A variety of field testing kits are
considered to be adequate for most chlorine interference checks and a maximum
detection limit of 0.5 mg/L is allowed. Ref: NC WW/GW LC Policy.
Comment: The laboratory checks for TRC upon grab sample collection on Monday,
Wednesday and Friday, but not Tuesday, Thursday, Saturday or Sunday.
Recommendation: It is recommended the laboratory check for the presence or absence
of TRC using test strips, and document the results on the benchsheet or Chain of
Custody.
The paper trail consisted of comparing original records (e.g., laboratory benchsheets, logbooks,
etc.) and contract lab reports to electronic Discharge Monitoring Reports (eDMRs) submitted to
the North Carolina Division of Water Resources. Data were reviewed for Tarboro WWTP
Laboratory (NPDES permit # NC0020605) for January, May and August 2017. No transcription
errors were observed. The facility appears to be doing a good job of accurately transcribing
data.
V. CONCLUSIONS:
Correcting the above -cited Findings and implementing the Recommendations will help this
laboratory to produce quality data and meet Certification requirements. The inspector would like
to thank the staff for their assistance during the inspection and data review process. Please
respond to all Findings and include supporting documentation, implementation dates
and steps taken to prevent recurrence for each corrective action.
Report prepared by: Anna Ostendorff Date: April 19, 2018
Report reviewed by: Jason Smith Date: April 23, 2018

E
�
t
k
k
0.
2
�
J
�
4
/
)
E
a)
\
§
0
2
=
{
{
f
§
S
\
§
,2q
-
\
2
\
\
CL
$
k
\
/
§
0
{
00
t
\
\
7
_
Cl!}
\ \
i
.
k
\
\
(
\ z
e\\
°
y §
�\
/ ƒ \
\
\ !
\ ) \
�
§ \ c
§ /
) /
»
\ k
E c
$ &
) u «
u /
§ z / §
E ƒ \
ƒ u =
o
$ /
°
±—
\ \ »
f W C
o w 2§
2 < /
Fy
\ )
/ \
j \ \
» u
\ \
e o
2\
\
0 ) %
§ \ \
w
§' 6
m o
6 2 0° z
== d e co
G`
|-
z s a
o/ o
o/ g) K o
o& o) /
)}
w
)§
k
a E 2
2( e
§- 0
cl�g>
) u r o=
o» g o>
= a G
> e a E\
=
0 o o
u 0
2 0 2 $ 2
2 7 2
] )
/
/ ®i
° j ®/
®E ®� 2 ®£
®± ®( ®
} k