NC0020117_Lab Inspection_20011025

Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Gregory J. Thorpe, Ph.D.
Acting Director
Division of Water Quality
October 25, 2001
114
Mr. J. Enique Coello
Clinton -Norman H. Larkins WWTP Lab.
P.O. Box 199
Mill Branch Road
Clinton, NC 28328
SUBJECT: Laboratory Certification Maintenance Inspection
Dear Mr. Coello:
OCT 2 9 2001
Enclosed is a report for the inspection performed on October 11, 2001 by Mr.
Frederick L. Bone. Where deficiencies are cited in this report, a response is required as
well as for all lettered comments and/or recommendations cited. Within thirty days of
receipt, please supply this office with a written item for item description of how these
deficiencies, comments and/or recommendations were corrected. If the deficiencies cited
in the enclosed report are not corrected, enforcement actions will be recommended. For
certification maintenance, your laboratory must continue to carry out the requirements set
forth in 15A NCAC for 2H .0800.
Copies of the checklists completed during the inspection may be requested from
this office. Thank you for your cooperation during the inspection. Please contact us at
919-733-3908, if you have questions or need additional information.
Sincerely,
9. w
James W. Meyer
Laboratory Section
Enclosure
cc: Frederick L. Bone
Fayetteville Regional Office
♦FPS+
NCDENR
Laboratory Section N. C. Division of Water Quality 1623 Mail Service Center Raleigh, NC 27699-1623 [phone]
FAX: [phone] Internet: www.esb.enr.state.nc.us/lab

On -Site Inspection Report,
LABORATORY NAME:
ADDRESS:
CERTIFICATE NO:
DATE OF INSPECTION:
TYPE OF INSPECTION:
EVALUATOR:
LOCAL PERSON(S) CONTACTED:
I. INTRODUCTION:
Clinton —Norman H. Larkins VVV TP Lab.
P.O. Box 199
Mill Branch Road
Clinton, NC 28328
114
October 11, 2001
Maintenance
Frederick L. Bone
Ricky Coello
This laboratory was inspected to verify its compliance with the requirements of 15A NCAC 2H
.0800 for the analysis of environmental samples.
II. GENERAL COMMENTS:.
The laboratory is spacious and well equipped. All facilities and equipment are well maintained.
Records are well kept and most data looked good. Some further quality control procedures need
to be implemented.
III. DEFICIENCIES, RECOMMENDATIONS, REQUIREMENTS, AND COMMENTS:
General:
1. DEFICIENCY: The laboratory is not performing sufficient quality control for it's duplicate
sample analysis. The laboratory must calculate either the relative percent difference, or the
absolute difference for each duplicate pair analyzed. This value is then used to establish
control charts or other appropriate acceptance criteria. This type of data is necessary to
demonstrate that the data is within acceptable control limits. The %RPD must be listed on the
inorganic benchsheets so that the analyst will be able to immediately confirm whether or not
the data falls within acceptable limits.
REQUIREMENT: Any time quality control results indicate an analytical problem, the problem
must be resolved, and any samples involved must be rerun if the holding time has not expired.
Ref: 15A NCAC 2H .0805 (a) (7) (f).
2. DEFICIENCY: The laboratory is not verifying the automatic temperature compensation of
the pH and Conductivity meter on an annual basis.

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REQUIREMENT: All thermometers must meet National Institute of Standards and Technology
(NIST) specifications for accuracy or be checked against a NIST traceable thermometer and
proper corrections made. Ref: 15A NCAC 2H .0805 (a) (7) (o).
3. DEFICIENCY: Some of the daily Togs and benchsheets used by the laboratory do not
contain all of the necessary labeling information. No units of measure are associated with
some of the data values listed in the logbooks and on laboratory benchsheets. Incorrect units
of measure were listed on some of the logs for temperature.
REQUIREMENT: The laboratory must review all benchsheets and logbooks to ensure that
every entry is marked with the appropriate units of measure. Every number recorded on a
benchsheet or logbook must have an appropriate unit assigned to it. 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 .0800 (a) (7) (h).
A. COMMENT: The laboratory does not clearly label duplicate samples on the general
worksheets.
RECOMMENDATION: For duplicate samples, the sample name should be followed by the
term "Dup". or "Duplicate" to indicate sample duplication. This will clearly delineate duplicate
samples from regular samples.
B. COMMENT: The laboratory does not list the acceptance ranges of quality control samples
on the laboratory benchsheets.
RECOMMENDATION: It is strongly recommended that the laboratory list the acceptance
ranges for each quality control sample on the benchsheet. This will enable the analyst to be
able to compare the analytical result to the acceptable range in a timely fashion. If the sample
is out of the acceptable range, it can then be reanalyzed immediately and within all holding
times.
C. COMMENT: The laboratory does not analyze a second source QC standard for all required
parameters.
REQUIREMENT: Analyze one known standard in addition to calibration standards each day
that samples are analyzed to document accuracy. This laboratory control standard must be
from a second source. For held curves for colorimetric methods, it must be analyzed after the
calibration verification standard is analyzed. It is recommended that this laboratory control
standard, like the calibration verification standard, have a mid -range concentration and not
vary by more than ± 10%. If it does the analysis is out of control. The analysis must be
terminated and the problem corrected. Ref: 15A NCAC 2H .0805 (a) (7) (B), (F), and Standard
Methods, 18th Edition - Method 1020 6.3.

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D. COMMENT: The Laboratory is measuring and recording the temperature and pressure of
the autoclave daily. The thermometer used to monitor this temperature is not checked against
an autoclave maximum holding thermometer weekly.
REQUIREMENT: Check the operating temperature weekly with a minimum/maximum holding
thermometer. Ref: Standard Methods, 18th Edition - Method 9020 B. 2. i.
E. COMMENT: The laboratory adjusts oven temperatures to achieve 103 -105°C for TSS and
TS analysis. On days that adjustments are made to the oven, the laboratory does not record that
the proper temperature of 103 -105°C is achieved.
REQUIREMENT: Dry evaporated sample for at least 1 hour in an oven at 103-105°C, cool in
desiccator to balance temperature, and weigh. Ref: Standard Methods 18th Edition 2540 D
Total Suspended Solids at 103 -105° C section (3) c p2-56.
F. COMMENT: The thermometer in the drying oven is currently reading the internal air
temperature and not the sample matrix temperature.
RECOMMENDATION: The thermometer in the drying oven should be placed in a beaker of
sand or other solid matrix. This ensures that the proper matrix temperature is measured as
well as providing a more stable temperature environment for the thermometer readings.
G. COMMENT: The laboratory does not qualify data that does not meet established quality
control criteria.
RECOMMENDATION: The laboratory must qualify all data that does not meet the quality
control criteria established by either laboratory controls or by criteria given in each individual
method. For example if the GGA is not within the control limits for a given day, the data should
be reported and the results qualified with a note that indicates the laboratory recognizes that
the GGA is out of range, but that in the technicians professional opinion that the data is valid.
Any variation in data quality should be explained by qualifying the data.
Total Suspended Solids:
4. DEFICIENCY: The laboratory is not filtering enough sample to get between 1 and 200 mg of
residue on each filter.
REQUIREMENT: When analyzing suspended residue, sufficient sample must be filtered to yield
at least 1.0 mg of residue. Ref: EPA-600/4-79-020 Methods Manual, March 1979 - Method
160.2. The size of a total suspended solid sample must be between 1 and 200 mg. Limit the
sample size to that yielding no more than 200 mg of residue. Ref: Standard Methods, 18th
Edition - Method 2540 D. Total Suspended Solids Dried at 103-105°C section (3) c p. 2-56.
5. DEFICIENCY: The laboratory does not properly rinse all filters prior to analysis.

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REQUIREMENT: Apply vacuum and wash disks with three successive 20-ml portions of
reagent —grade water. Continue suction to remove all traces of water and discard washings.
Ref: Standard Methods 18th Edition 2540D. (3) (A) p. 2-56.
6. DEFICIENCY: The laboratory is not rinsing filtered samples with three successive rinses of
10 ml of reagent grade water.
REQUIREMENT: Wash 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. Ref: Standard Methods 18th Edition 2540 C Total Suspended Solids Dried at 103-
105°C-section (3) c p. 2-56.
H. COMMENT: The laboratory does not record the time and date that the samples were
placed into the oven and time and date that the samples were removed from the oven on the
laboratory benchsheet for the annual dry weight verification study.
REQUIREMENT: The laboratory must record the time and date that the samples were placed
into the oven and time and date that the samples were removed from the oven on the
benchsheet for the annual drying time verification study. Repeat cycle of drying, cooling,
desiccation, and weighing until a constant weight is obtained, or until weight change is less
than 4% of previous weight or 0.5 mg, whichever is less. Ref: Standard Methods 18th Edition
2540 D Total Suspended Solids at 103 -105° C section (3) c p2-56.
I. COMMENT: The laboratory is not analyzing a sufficient sample volume for water blanks for the
Total Suspended Solids analysis. The laboratory must filter a volume of DI water (equal to the
maximum sample volume used) as a method blank each analysis day.
REQUIREMENT: The laboratory must analyze blanks at a volume equal to the maximum
sample volume used as a methodblank each analysis day. Blanks must be analyzed in order to
determine bias in each sample batch. Ref: Standard Methods 18th Edition - Method 1020B pg.
1-5.
J. COMMENT: The laboratory does not fully calculate and record each blank sample analyzed.
REQUIREMENT: The laboratory must treat each blank analyzed exactly as all other samples.
The blanks must be recorded and fully calculated on each analysis day.
Total Solids:
Note: The laboratory is not currently certified for this parameter. Samples are anayzed for
industrial pretreatment by this method in order to determine the % solids. If the laboratory
desires certification for this parameter the following items must be corrected in order to
meet method criteria.

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7. DEFICIENCY: The laboratory is not analyzing water blanks for this analysis. The laboratory
must filter a volume of DI water (equal to the maximum sample volume used) as a method blank
each analysis day.
REQUIREMENT: Blanks must be analyzed in order to determine bias in each sample batch.
Ref: Standard Methods, 18 Edition - Method 2020 pg. 2-1.f.
8. DEFICIENCY: The laboratory is not using a sample that yields between 10 and 200 mg of
dried residue.
COMMENT: The laboratory does not record the amount of dried residue that remains after
drying on the laboratory benchsheet. This information must be recorded in order to demonstrate
that all method requirements are achieved.
REQUIREMENT: Choose sample volume to yield between 10 and 200mg dried residue. Ref:
Standard Methods 18th Edition 2540 C. Total Dissolved Solids Dried at 180° C section (3) c p.
2-55.
9. DEFICIENCY: The laboratory does not record the volume of sample analyzed on the
laboratory 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 .0800 (a) (7) (h).
10. DEFICIENCY: The laboratory does not record the time and date that the samples were
placed into the oven and time and date that the samples were removed from the oven on the
bench sheet.
REQUIREMENT: The laboratory must record the time and date that the samples were placed
into the oven and time and date that the samples were removed from the oven on the bench
sheet. The method requires that the samples be dried for at least one hour. The laboratory
must document that this minimum drying time is performed. Ref: Standard Methods 18th
Edition 2540 B. Total Solids Dried at 103 -105° C section (3) b p2-54.
11. DEFICIENCY: The laboratory is not analyzing any duplicate samples.
REQUIREMENT: Excluding oil and grease, 5% of all samples must be analyzed in duplicate.
15A NCAC 2H .0805 (a) (7) (C).
K. COMMENT: If the laboratory desires to become certified for this parameter, all of the
following requirements must be completed.

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REQUIREMENT: 1. The laboratory must provide a written request for certification.
2. Acceptable Performance Evaluation samples must be provided.
3. Correct any comments and deficiencies cited in this audit report.
4. Payment of the additional parameter invoice must be received.
AMMONIA:
12. DEFICIENCY: The laboratory is not analyzing and recording a standard at the mid -range
of the calibration curve daily for the ammonia analysis.
COMMENT: As was discussed at the time of the audit the mid -range is to be defined as one
half the concentration of the high standard.
Note: The mid -range check standard must be prepared from the same stock standards as the
analytical curve. A second source laboratory control. standard (LCS) must be analyzed in
addition to the mid -range check standard daily. A second source LCS sample does not
constitute daily mid -range verification.
REQUIREMENT: Verify the standard curve daily by analyzing one or more standards within
the linear range, as specified in the individual method. The curve must be updated as set forth
in the standard procedures, each time the slope changes by more than 10 percent at
midrange. Ref: Standard Methods 18th Edition 1020 B. Quality Control section 5 p. 1-5, and
Ref: 15A NCAC 2H .0805 (a) (7) (i).
L. COMMENT: The curve used for ammonia analysis covers too wide of an analytical range.
(0.1-100 mg/L)
RECOMMENDATION: In order to increase the accuracy and stability of the analytical
measurement, it is recommended that the laboratory analyze two separate ammonia curves.
The first curve from 0.1 - 1.0 mg/L and the second curve 1.0 — 20 mg/L. Sample
concentrations above 20 mg/L should be diluted to fall within the range of the curve.
M. COMMENT: The laboratory is not documenting the pH preservation of ammonia samples.
Note: The laboratory does not routinely preserve samples. Samples are normally analyzed
immediately after collection.
REQUIREMENT: The laboratory must document that all residual chlorine has been removed
and that the pH of all samples has been properly adjusted. A record of date collected, time
collected, sample collector and use of proper preservatives must be maintained. Ref: 15A
NCAC 2H .0805 (a) (7) (M).
N. COMMENT: The laboratory records a check mark rather than the actual concentration for
all ammonia standards daily.

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RECOMMENDATION: It is strongly recommended that the laboratory record the actual
concentration of the calibration standards daily. This will provide the laboratory with more
useful information than a check mark.
pH and Residual Chlorine:
O. COMMENT: The laboratory benchsheets cite Standard Methods 17' Edition.
REQUIREMENT: The laboratory is following Standard Methods 18th Edition. The laboratory must
correct its benchsheets to reflect the method currently used by the laboratory for sample
analysis.
RESIDUAL CHLORINE:
13. DEFICIENCY: The permitted limit at this facility for residual chlorine is 17µg/I. The annual
curve for the pocket colorimeter demonstrated a lack of sensitivity below 50 µg/L. The
laboratory also has a DR 3000 spectrophotometer. The annual curve for this instrument
demonstrated adequate sensitivity at 25µg/L. The laboratory recently upgraded to a DR 4000
spectrophotometer. No analytical curve has been analyzed for the DR4000, but samples are
analyzed on this instrument. The DR 4000 shouldbe able to meet the permitted limit, but this
can not be demonstrated without the required analytical curve.
REQUIREMENT: The laboratory must use instrumentation capable of obtaining reliable data
at or below the facility permitted limits. The laboratory .must immediately analyze a curve for
the DR 4000 if samples are to be reported using this instrumentation. For analytical
procedures requiring analysis of a series of standards, the concentrations of these standards
must bracket the concentration of the samples analyzed. One of the standards must have a
concentration equal to the laboratory's lower reporting concentration for the parameter
involved. For colorimetric analyses, a series of five standards for a curve prepared annually or
three standards for curves established each day or standards as set forth in the analytical
procedure must be analyzed to establish a standard curve. The curve must be updated as set
forth in the standard procedures, each time the slope changes by more than 10 percent at
mid -range, each time a new stock standard is prepared or at least every twelve months. Each
analyst performing the analytical procedure must produce a standard curve. Ref: 15A NCAC
2H .0800 (a) (7) (I).
14. DEFICIENCY: The laboratory is not analyzing a blank daily.
REQUIREMENT: Analyze reagent blanks whenever new reagents are used and as often as
required in specific methods. Analyze a minimum of 5% of the sample Toad as reagent blanks;
this monitors purity of reagents and the overall procedural blank. Analyze a reagent blank after
any sample with a concentration greater than that of the highest standard or that might result
in carryover from one sample to the next. Ref: Standard Methods 18th Edition 1020B Quality
Control (4) p 1-5.

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P. COMMENT: The laboratory is not calculating a correlation coefficient for the standard curve
for the residual chlorine analysis. The laboratory does not demonstrate statistically that the
analytical curve is linear.
REQUIREMENT: The laboratory must calculate a correlation coefficient for each analytical
curve in order to demonstrate linearity. Analytical. Quality Control Program. 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. The quality control document
shall be available for inspection by the State Laboratory. Ref: 15A NCAC 2H .0805 (a) (7).
CONDUCTIVITY:
15. DEFICIENCY: Not all samples reported by the laboratory are properly bracketed with
calibration standards.
COMMENT: The lab may choose to make a higher standard using the chart in Standard
Methods, 18 Edition- Method 2510 Table 2510:1. pg. 2-43 to bracket the higher sample values.
REQUIREMENT: For analytical procedures requiring a series of standards, the concentrations
of these standards must bracket the concentration of the samples analyzed, and one of the
standards must have a concentration equal to the laboratory's lower reporting limit. Ref: 15A
NCAC 2H .8005 (a) 97) (1).
Q. COMMENT: Variations in the daily cell constant indicate that the conductivity probe is in
need of maintenance.
RECOMMENDATION: Based on the daily conductivity information, it is recommended that the
laboratory perform maintenance on the conductivity probe.
Fluoride:
16. DEFICIENCY: The laboratory is not analyzing any duplicate samples for this parameter.
REQUIREMENT: Excluding oil and grease, 5% of all samples must be analyzed in duplicate.
Ref: 15A NCAC 2H .0805 (a) (7) (C).
17. DEFICIENCY: The laboratory is not analyzing water blanks for this analysis. The laboratory
must filter a volume of DI water (equal to the maximum sample volume used) as a method blank
each analysis day.
REQUIREMENT: Blanks must be analyzed in order to determine bias in each sample batch.
Ref: Standard Methods, 18 Edition - Method 2020 pg. 2-1.f.

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R. COMMENT: The linearity of curves used for fluoride analysis does not meet accepted
criteria. The correlation of the laboratory fluoride curves is 0.993. This does not meet a
minimum of 0.995 correlation.
REQUIREMENT: The regressing calculation will generate a correlation coefficient (r) that is a
measure of the goodness of fit of the regression line to the data. A value of 1.00 indicates a
perfect fit. In order to be used for quantitative purposes, the correlation coefficient must be
greater than or equal to 0.995.
17. DEFICIENCY: The laboratory is performing a 10X dilution on all samples analyzed. The
laboratory does not record that any dilution has been performed on the laboratory general
worksheet.
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 .0800 (a) (7) (h).
S. COMMENT: The laboratory is performing a five -point annual calibration curve for fluoride. In
addition to the five -point curve, the laboratory is performing a three-point calibration curve
daily.
REQUIREMENT: The laboratory must perform EITHER a daily three-point calibration or a five
point annual calibration for this method.
BOD:
18. DEFICIENCY: The laboratory does not determine the amount of sodium sulfite necessary
to neutralize the residual chlorine as described in the approved method.
Note: Excess sodium sulfite will cause an increase in the reduction potential of each sample.
For this reason, the method requires that only the exact amount sodium sulfite that is
necessary be used to neutralize each sample.
REQUIREMENT: The laboratory must perform the titrametric test for the removal of residual
chlorine, and the amount of sodium sulfite necessary to neutralize that chlorine as described in
Standard Methods, 18th Edition p. 5-4.
19. DEFICIENCY: The laboratory does not use the sodium sulfite solution in order to
neutralize residual chlorine. The laboratory is currently using sodium thiosulfate for this
purpose.
REQUIREMENT: Prepare sodium sulfite solution as described in the method. This solution is
not stable; prepare daily. Ref: Standard Methods, 18 Edition - Method 5210 B (3) (f) pg. 5-3.

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Fecal Coliform:
T. COMMENT: The blanks used for fecal coliform analysis are not clearly labeled. They are
listed as I or II.
REQUIREMENT: The laboratory must clearly label each blank. 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 .0800 (a) (7) (h).
U. COMMENT: The laboratory lists non -reportable samples on the same benchsheet as the
reportable data. Some of the process control data does not meet the requirements of the cited
methodology.
RECOMMENDATION: The laboratory must either clearly label all non -certified work on the
laboratory benchsheet or have separate benchsheets for process control (non -certified) and
reportable (certified) data. This will allow the laboratory to demonstrate that all data used for
reporting purposes has met all method requirements.
V. COMMENT: The laboratory includes values from dilutions that do not meet the 20-60
colonies per plate method criteria in reporting the final value to be reported. The laboratory
analyzes a 100ml-sample volume. Data should be reported from the 100m1 sample unless it is
outside the desired counting range or other dilutions yield results in the accepted range. All
results that meet the method acceptance criteria must be averaged to obtain a final value to
be reported.
Note: The only time that a laboratory may report data as <l colony/100m1 is if a whole volume
100 ml sample is analyzed. All other data must either meet the 20 — 60 colony count rule or be
qualified and reported as an estimated value.
REQUIREMENT: Compute the density from the sample quantities that produced MF counts
within the desired range of 20 to 60 fecal coliform colonies. Ref: Standard Methods, 18th
Edition 9222D. (3) pg. 9-61.
W. COMMENT: The samples analyzed for fecal coliform have too much variability between the
sample results and the dilutions analyzed.
Example: Dilution: Filter Count: Filter Count
100m1 8/7/01 282 7/24/01 50
100m1 8 184
25m1 3 17
1ml 0 1

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REQUIREMENT: Samples must be well mixed prior to each dilution being poured. This will
ensure agreement between each duplicate and dilution analyzed.
IV. PAPER TRAIL INVESTIGATION:
This consisted of comparing data reported on DMR's submitted to this Division for the months of
January, July, and August 2001 with the values obtained on laboratory bench worksheets. The
review of this data indicated no problems in proper data reporting.
V. CONCLUSIONS:
Correcting the above deficiencies and comments and implementing the recommendations
should help this lab to produce quality data and meet certification requirements.
Please respond to all Deficiencies and lettered Comments and/or
Recommendations cited in this report.
Report prepared by: Frederick L. Bone Date: October 19, 2001