#560_2018_0403_JS_FINAL.doc

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To be attached to all inspection reports in-house only.
Laboratory Cert. #:
560
Laboratory Name:
Unimin Corporation — Red Hill
Inspection Type:
Industrial Maintenance
Inspector Name(s):
Jason Smith
Inspection Date:
April 3, 2018
Date Forwarded for Initial
Review:
April 20, 2018
Initial Review by:
Tonja Springer
Date Initial Review
Completed:
April 23, 2018
Cover Letter to use:
❑ Insp. Initial
❑Insp. No Finding
❑Corrected
❑ Insp. Reg
®Insp. CP
❑Insp. Reg. Delay
Unit Supervisor/Chemist III:
Todd Crawford
Date Received:
4/24/18
Date Forwarded to Admin.:
5/7/2018
Date Mailed:
5/7/2018
Special Mailing Instructions:

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Water Resources
ENVIRONMENTAL GUAL[TY
May 7, 2018
560
Mr. Dennis W. Johnson
Unimin Corporation - Red Hill
P.O. Box 100
Bakersville, NC 28705
ROY (1 1) F., R
MIC;HEAL S. REGAN
LINDA C ULl'EP )FR
SUBJECT: North Carolina Wastewater/Groundwater Laboratory Certification (NC WW/GW LC)
Maintenance Inspection
Dear Mr. Johnson:
Enclosed is a report for the inspection performed on April 3, 2018 by Jason Smith. 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].
Sincerely,
le
Todd Crawford
Technical Assistance & Compliance Specialist
NC WW/GW Laboratory Certification Branch
Attachment
cc: Dana Satterwhite, Jason Smith
Water Sciences Section
NC Wastewater/Groundwater Laboratory Certification Branch
1623 Mail Service Center, Raleigh, Noah Carolina 27699-1623
Location: 4405 Reedy Creek Road; Raleigh, North Carolina 27607
Phone: [phone], FAX: [phone]
Internet: http:tldeq. nc.qov/aboutldivisionstwater-resourceslwater-resources-data/water-sciences-home-page/laboratory-certification-branch

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AUDITOR(S):
LOCAL PERSON(S) CONTACTED:
INTRODUCTION:
Unimin Corporation — Red Hill
NC0085839
2241 Highway 197 N
Bakersville, NC 28705
560
April 3, 2018
Industrial Maintenance
Jason Smith
Dennis Johnson, Rick Singleton, Andy Greene and Steve Wilson
This laboratory was inspected by a representative 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 environmental samples.
II. GENERAL COMMENTS:
A review of laboratory benchsheets, requested by Linda Wiggs, Environmental Senior Specialist
of the NC Department of Environmental Quality Asheville Regional Office, indicated that the
laboratory had not implemented requirements associated with the 2012 and 2017 updates of the
Code of Federal Regulations, Title 40, Part 136. Ms. Wiggs requested that a laboratory inspection
be performed in conjunction with her facility inspection in order to ensure compliance with Federal
and State regulations. Laboratory personnel from other certified Unimin Corporation facilities also
attended the inspection to implement all requirements at their facilities as well.
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 Quality Assurance (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 1, 2019.

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#560 Unimin Corporation — Red Hill
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., Quality Control (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 Meritech, Inc. (Certification # 165).
III. FINDINGS, REQUIREMENTS, COMMENTS AND RECOMMENDATIONS:
General Laboratory
Recommendation: Laboratory personnel have changed at both facilities since the last inspection.
Due to the number of Findings in this report that were cited in the previous report, it is
recommended that the laboratory adopt a formal documented training process for new employees
which includes, at a minimum, documentation of the following:
® staff have the appropriate education, training, experience and/or demonstrated skills, as
required to generate quality control results within method -specified limits
® staff have read the laboratory Quality Assurance Manual and/or applicable SOPS
® staff have obtained acceptable results on unknown performance evaluation samples or
other demonstrations of proficiency
A. Finding: The laboratory did not have a copy of the approved analytical procedures for
Fluoride and Turbidity.
Requirement: Each laboratory requesting certification must contain or be equipped with
the following: A copy of each approved analytical procedure being used in the laboratory.
Ref: 15A NCAC 2H .0805 (a) (6) (F).
Comment: The approved analytical procedures are in Standard Methods, 22"d Edition.
The laboratory has the 20t" Edition of Standard Methods. Copies of the Approved
Procedures for pH and Settleable Residue were provided to the laboratory.

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#560 Unimin Corporation — Red Hill
Documentation
B. Finding: The laboratory does not report results of all tests on the characteristics of the
effluent.
Requirement: The results of all tests on the characteristics of the effluent, including but
not limited to NPDES permit monitoring requirements, shall be reported on the monthly
report forms. Ref: 15A NCAC 2B .0506 (b) (3) (J).
Requirement: If more than one pH concentration has been taken for a particular day,
these values cannot be averaged due to the logarithmic nature of pH concentration. All
values must be reported on the electronic Discharge Monitoring Report (eDMR), either in
the daily cell or the comments section. The following convention must be followed when
deciding which value to report in the daily cell:
Any value in violation of permit limits must be reported in the daily cell. If multiple
samples yielded noncompliant results, the most extreme noncompliant value must
be reported in the daily cell.
If all values taken during the day were compliant with the permit limits, the value
closest to the bounds of the limit range (high or low) must be reported in the daily
cell.
Ref: NC WW/GW LC Approved Procedure for the Analysis of pH.
Comment: The laboratory reports the first result obtained when duplicates are analyzed.
Except for pH, the average of the results may be reported to fulfill this requirement.
Comment: Duplicates are not required for Field Parameter analyses (pH and Settleable
Residue). If they are analyzed voluntarily, both values must be reported.
C. Finding: The laboratory benchsheets contained data that could be considered falsified.
Requirement: "Falsified data or information" means data or information which has been
made untrue by alteration, fabrication, omission, substitution, or mischaracterization. The
agency need not prove intent to defraud to prove data is falsified. Ref: 15A NCAC 2H
.0803(6).
Comment: The laboratory generally records the results from daily analyses in the
computer and prints the benchsheet. Settleable Residue is only analyzed once per week,
but laboratory personnel stated that their results are always <0.1 mL/L and that the results
of previous analyses were inadvertently left on the printed benchsheet for days when the
analysis was not actually performed. The laboratory implemented and submitted an
updated benchsheet on April 4, 2018 which removed the documentation of Settleable
Residue analysis.
Recommendation: It is recommended, to prevent recurrence, that the laboratory
include instructions in the Quality Assurance Manual/Standard Operating Procedure
stating that benchsheet templates are never to be store with previously entered data.
D. Finding: All original records are not being maintained for five years.

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#560 Unimin Corporation — Red Hill
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 is documenting the annual pH meter temperature sensor check
on a sticker by the meter which is replaced each year. Checking this pH meter is no longer
required since it is not used for Temperature analysis; however, as noted in Finding O, the
thermometers in the oven, sample storage refrigerator and compositor must be checked
annually. Documentation of these thermometer checks must be maintained for five years.
E. 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). A system (e.g.,
traceable identifiers) must be in place that links standard/reagent preparation information
to analytical batches in which the solutions are used. Documentation of solution
preparation must include the analyst's initials, date of preparation, the volume or weight of
standard(s) used, the solvent and final volume of the solution. This information as well as
the vendor and/or manufacturer, lot number, and expiration date must be retained for
primary standards, chemicals, reagents, and materials used for a period of five years.
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.
Comment: Please note that the requirement to document solution preparation includes
the Fluoride standard required in Finding V.
F. Finding: Error corrections are not always properly performed.
Requirement: All documentation errors must be corrected by drawing a single line
through the error so that the original entry remains legible. Entries shall not be obliterated
by erasures or markings. Wite-Out®, correction tape or similar products designed to
obliterate documentation are not to be used. Write the correction adjacent to the error.
The correction must be initialed by the responsible individual and the date of change
documented. All data and log entries must be written in indelible ink. Pencil entries are not
acceptable. Ref: NC WW/GW LC Policy.
Comment: Error corrections were not being dated.
G. Finding: The laboratory benchsheet was lacking pertinent data: time of sample analysis.
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: Date and time of sample analysis to verify the 15-minute holding
time is met [Alternatively, one time may be documented for collection and analysis with the
notation that samples are measured in situ or immediately at the sample site.] Ref: NC
WW/GW LC Approved Procedure for the Analysis of pH.

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#560 Unimin Corporation — Red Hill
Comment: This Finding applies to the pH time of analysis of the effluent. The time of pH
analysis of stream samples is documented.
H. Finding: The laboratory benchsheet was lacking pertinent data: meter calibration.
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: Meter calibration and meter calibration time(s). Ref: NC WW/GW
LC Approved Procedure for the Analysis of pH.
Comment: This Finding applies to the calibration of the pH meter used for stream
samples. The calibration of the pH meter used for effluent samples is being documented.
I. Finding: The laboratory benchsheet 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).
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 pH.
Comment: This Finding applies to both pH meters.
J. 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
21-1.0805 (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 pH.
Comment: This Finding applies to both pH meters.
K. Finding: The laboratory benchsheet was lacking pertinent data: method references.
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
21-1.0805 (a) (7) (A).
Requirement: The following must be documented in indelible ink whenever sample
analysis is performed: method reference. Ref: NC WW/GW LC Approved Procedure for
the Analysis of pH and NC WW/GW LC Approved Procedure for the Analysis of Settleable
Residue.
Comment: This Finding applies to pH and Settleable Residue.

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#560 Unimin Corporation — Red Hill
L. Finding: The laboratory benchsheet for Settleable Residue was lacking pertinent data:
sample volume.
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. The date and time BOD and coliform samples are removed from the incubator
must be included on the laboratory worksheet. Ref: 15A NCAC 2H .0805 (a) (7) (H).
Requirement: The following must be documented in indelible ink whenever sample
analysis is performed: Volume of sample analyzed. Ref: NC WW/GW LC Approved
Procedure for the Analysis of Settleable Residue.
M. Finding: The laboratory benchsheet for Settleable Residue was lacking pertinent data: 45-
minute sample stir 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).
Requirement: The following must be documented in indelible ink whenever sample
analysis is performed: 45-minute stir time (use of a check box is acceptable). Ref: NC
WW/GW LC Approved Procedure for the Analysis of Settleable Residue.
Quality Control
N. Finding: Precision (e.g., relative percent difference) and accuracy (e.g., percent recovery)
of QC results are not calculated, evaluated and documented to demonstrate the analytical
process is in control and the established acceptance criteria are 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: 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 with a brief description of the QC exceedance that occurred.
®. Finding: The laboratory is not checking all thermometers with a National Institute of
Standards and Technology (NIST) traceable thermometer annually.
Requirement: All thermometers must meet NIST specifications for accuracy or be
checked, at a minimum annually, against a NIST traceable thermometer and proper
corrections made. Ref: 15 NCAC 2H .0805 (a) (7) (0).
Requirement: All thermometers and temperature measuring devices must be checked
every 12 months against a NIST certified or NIST traceable thermometer and the process
documented. Ref: NC WW/GW LC Policy.

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#560 Unimin Corporation — Red Hill
Comment: The laboratory must check the thermometers in the oven, sample storage
refrigerator and compositor annually.
Comment: The laboratory was checking the temperature sensor of the pH meter
annually, but this is not required since it is not used for Temperature analysis.
P. Finding: The analytical balance is not being checked with three weights quarterly. Cited
previously on July 20, 2009.
Requirement: The analytical balance must be checked with one class S, or equivalent,
standard weight each day used and at least three standard weights quarterly. The values
obtained must be recorded in a log and initialed by the analyst. Ref: 15A NCAC 2H .0805
(a) (7) (K).
Q. Finding: The analytical balance weights have not been verified against ASTM standard
weights in the past 5 years.
Requirement: ASTM Class 1 and 2 weights must be verified at least every 5 years. ASTM
Class 1 weights (20 g to 25 kg) and ASTM Class 2 weights (10 g to 1 mg) are equivalent
to the NBS Class S weights specified in 15A NCAC 2H .0805 (a) (7) (K). Ref: NC
WW/GW LC Policy.
R. Finding: The laboratory has not calibrated the Eppendorf pipet used for preparing PT
Samples.
Requirement: Mechanical volumetric liquid -dispensing devices (e.g., fixed and adjustable
auto-pipettors, bottle -top dispensers, etc.) must be calibrated at least twice per year,
approximately six months apart. Each liquid -dispensing device must meet the
manufacturer's statement of accuracy. For variable volume devices used at more than one
setting, check the accuracy at the maximum, middle and minimum values. Testing at more
than three volumes is optional. When a device capable of variable settings is dedicated to
dispense a single specific volume, calibration is required at that setting only. Ref: NC
WW/GW LC Policy.
Proficiency Testing
S. Finding: Additional QC beyond what is routine for Compliance Samples is being analyzed
with PT Samples.
Requirement: Laboratories shall conduct the analyses in accordance with their routine
testing, calibration and reporting procedures, unless otherwise specified in the instructions
supplied by the Accredited PT Sample Provider. This means that they are to be logged in
and analyzed using the same staff, sample tracking systems, standard operating
procedures including the same equipment, reagents, calibration techniques, analytical
methods, preparatory techniques (e.g., digestions, distillations and extractions) and the
same quality control acceptance criteria. PT Samples shall not be analyzed with additional
quality control. They are not to be replicated beyond what is routine for Compliance
Sample analysis. Although, it may be routine to spike Compliance Samples, it is neither
required, nor recommended, for PT Samples. PT Sample results from multiple analyses
(when this is the routine procedure) must be calculated in the same manner as routine
Compliance Samples. Ref: Proficiency Testing Requirements, May 31, 2017, Revision 2.0.

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#560 Unimin Corporation — Red Hill
Comment: Corrective -action PT Samples, that are provided with the true values in a
sealed envelope, are not considered PT Samples and do not meet the PT requirements
outlined in 15A NCAC 2H .0800. In general, laboratories must not analyze PT Samples
with known concentrations along with PT Samples with unknown concentrations, as this is
not the routine testing protocol for Compliance Samples. This is not to say that they cannot
be used for troubleshooting purposes before analyzing a remedial PT Sample. This would
be considered part of the corrective action plan.
T. Finding: The laboratory is not documenting PT Sample analyses in the same manner as
routine Compliance Samples.
Requirement: All PT Sample analyses must be recorded in the daily analysis records as
for any Compliance Sample. This serves as the permanent laboratory record. Ref:
Proficiency Testing Requirements, May 31, 2017, Revision 2.0.
Comment: The laboratory documented the results only on the forms that are submitted to
the vendor.
U. 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.
Comment: The laboratory has multiple analysts, but the laboratory supervisor has
analyzed the PT Samples each year.
Fluoride — Standard Methods, 4500 F- C-2011 (Aqueous)
V. Finding: A Laboratory Fortified Blank (LFB) is not analyzed with each sample group.
Requirement: Include at least one LFB daily or per each batch of 20 or fewer samples.
Ref: Standard Methods, 4020 B-2011 (2) (e) and Table 4020:1.
Requirement: Prepare the LFM from the same reference source used for the LFB.
Reference: Standard Methods, 1020 B-2011 (7).
Comment: Preferably use the same concentration for the LFM as for the LFB to allow
analysts to separate the matrix's effect from laboratory performance.
W. Finding: A calibration blank is not analyzed initially, after every tenth sample (if applicable)
and at the end of the sample group. Cited previously on July 20, 2009.
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.

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#560 Unimin Corporation — Red Hill
Requirement: For the calibration verification to be valid, check standard results must not
exceed ± 10% of its true value, and calibration blank results must not be greater than one-
half the reporting level (unless the method specifies otherwise). Ref: Standard Methods,
4020 B-2011 (2) (b).
X. Finding: A calibration verification standard is not analyzed after every tenth sample (if
applicable) and at the end of the sample group.
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.
Requirement: For the calibration verification to be valid, check standard results must not
exceed ± 10% of its true value, and calibration blank results must not be greater than one-
half the reporting level (unless the method specifies otherwise). Ref: Standard Methods,
4020 B-2011 (2) (b).
Y. Finding: The laboratory is not analyzing an LFM and LFMD daily.
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 analyzes an LFM monthly and a sample duplicate daily.
Comment: The LFMD fulfills the State's requirement for analyzing a sample duplicate so
the laboratory may stop performing unspiked sample duplicate analyses when the LFMD
requirement is implemented.
Z. Finding: Distillation studies are not performed properly.
Requirement: Samples must be spiked according to the NC WW/GW LC Matrix Spike
Policy, in duplicate, to allow for a meaningful statistical comparison. It is recommended
that samples are spiked to yield a value within the verified calibration range so that sample
dilution is not needed. Comparisons between the matrix spike and matrix spike duplicate,
as well as between distilled and undistilled samples must meet a 20% RPD acceptance
criterion. Both the distilled and undistilled samples must be analyzed using the same
method technology used to report compliance data for the permitted facility. It is
recommended that both the distilled and undistilled portions of the sample be analyzed by
the same laboratory. Per 15A NCAC 2H .0805 (e) (2), it would be permissible to have a
contract lab distill the samples and send the distillates back to the permittee for analysis
within the prescribed holding time. Ref: NC WW/GW LC Policy. Please submit the
results of a distillation study properly performed by July 31, 2018.
Comment: The samples used for the distillation study were not spiked.
Residue, Suspended — Standard Methods, 2540 D-2011 (Aqueous)

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#560 Unimin Corporation — Red Hill
Comment: At the time of the inspection, the laboratory was decertified for Suspended Residue
due to two consecutive unacceptable PT results. The laboratory has performed corrective actions
and may be recertified after submitting the Corrective Action Report and an amendment form
requesting recertification.
AA. Finding: A quarterly check standard is not being analyzed.
Requirement: Analyze one suspended residue, one dissolved residue, one residual
chlorine and one oil and grease standard quarterly. 15A NCAC 2H .0805 (a) (7) (B).
BB. Finding: Filters are not weighed to constant weight prior to sample analysis, nor is a dry
filter blank analyzed with each set of samples. Cited previously on July 20, 2009.
Requirement: If pre -prepared filters are not used, the method requires that filters must be
weighed to a constant weight after washing. Repeat cycle of drying, cooling, desiccating,
and weighing until a constant weight is obtained or until weight change is less than 4% of
the previous weighing or 0.5 mg, whichever is less. In lieu of this process, it is acceptable
to analyze a single daily dry filter blank to fulfill the method requirement of drying all filters
to a constant weight prior to analysis. Ref: NC WW/GW LC Policy.
Comment: The laboratory analyzes a wet blank using 500 mL of reagent water, which is
not required.
CC. Finding: The samples are not weighed to constant weight, nor is an annual drying study
to verify the adequacy of the drying time, performed.
Requirement: Constant weights must be documented. The approved methods require the
following: "Repeat the cycle of drying, cooling, desiccating, and weighing until a constant
weight is obtained or until the weight change is less than 4% of the previous weight or 0.5
mg, whichever is less." In lieu of this, an annual study documenting the time required to
dry representative samples to a constant weight may be performed. Verify minimum daily
drying time is greater than or equal to the time used for the initial verification study drying
cycle. Drying cycles must be a minimum 1 hour for verification. Ref: NC WW/GW LC
Policy.
Comment: North Carolina allows for an annual drying study in lieu of the requirement
above to repeat the drying cycle for every sample. A random full set of samples should be
used for the drying study. The repeated drying time in the oven must be at least 1 hour
long. The time used for the annual drying study is the minimum time that samples are to
be dried until a new drying study is performed.
pH — Standard Methods, 4500 H+ B-2011 (Aqueous)
DD. 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

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#560 Unimin Corporation — Red Hill
reanalyzed, the data must be qualified. Ref: NC WW/GW LC Approved Procedure for the
Analysis of pH.
Comment: This Finding only applies to stream samples. The laboratory analyzes the
effluent on another meter.
IV. PAPER TRAIL INVESTIGATION:
The paper trail consisted of comparing original records (e.g., laboratory benchsheets, logbooks,
etc.) and contract lab reports to eDMRs submitted to the North Carolina Division of Water
Resources. Data were reviewed for Unimin Corporation — Red Hill (NPDES permit #
NC0085839) for July and December 2017 and January 2018. No transcription errors were
observed. The facility appears to be doing a good job of accurately transcribing data.
V. CONCLUSIONS:
We are concerned with the Findings that were cited previously and not corrected. The number
and severity of the Findings may make much of the data reported by the laboratory appear
questionable to third parties.
Laboratory Decertification Ref: 15A NCAC 2H .0807 (a) (1), (13) and (14):
A laboratory may be decertified for any or all parameters for up to one year for any or all of the
following infractions:
(1) Failing to maintain the facilities, or records, or personnel, or equipment, or quality control
program as set forth in the application, and these Rules; or
(13) Failing to respond to requests for information by the date due; or
(14) Failing to comply with any other terms, conditions, or requirements of this Section or of a
Laboratory certification.
Correcting the above -cited Finding(s) and implementing the Recommendation(s) will help this
laboratory to produce quality data and meet Certification requirements. The inspector would like
to thank the staff for its assistance during the inspection and data review process. Please
respond to all Findings and include supporting documentation and implementation
dates for each corrective action.
Report prepared by: Jason Smith Date: April 20, 2018
Report reviewed by: Tonja Springer Date: April 23, 2018

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