#5560_2020_1118_TLH_FINAL

December 7,2020

5560
Mr. Jonathan Murphrey
Piedmont Geologic P. C.
6003-145 Chapel Hill Road
Raleigh, NC 27607

Subject: North Carolina Wastewater/Groundwater Laboratory Certification (NC WW/GW
LC) Maintenance Inspection

Dear Mr. Murphrey:

Enclosed is a report for the inspection performed on November 18, 2020 by Tom Halvosa.
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. 251.

Sincerely,

Todd Crawford
Environmental Program Supervisor II
NC WW/GW Laboratory Certification
Branch

Attachment
cc: Tom Halvosa, Master File #5560

On-Site Inspection Report

LABORATORY NAME: Piedmont Geologic P. C.
INDUSTRIAL USE PERMIT #: WOLFFIN (NCSU Lot 86)
ADDRESS:

6003-145 Chapel Hill Road
Raleigh, NC 27607
CERTIFICATE #: 5560
TYPE OF INSPECTION Field Commercial Maintenance
AUDITOR: Tom Halvosa
DATE OF INSPECTION: November 18, 2020
LOCAL PERSON(S) CONTACTED: Jonathan Murphrey and Geoff Murphrey

I. INTRODUCTION:

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 02H .0800 for the analysis of compliance monitoring samples.

II. GENERAL COMMENTS:

The facility is neat and well organized and has all the equipment necessary to perform the analyses.
Staff members were forthcoming and responded well to suggestions from the auditor.

All required Proficiency Testing (PT) Samples have been analyzed and the laboratory has fulfilled its PT
requirements for the 2020 PT Calendar Year.

The inspector would like to commend the laboratory for staying current with changes in laboratory
certification program requirements and proactively implementing new requirements prior to the
established deadlines. The laboratory has comprehensive Standard Operating Procedures (SOPs) for
all parameters, which were submitted and reviewed prior to the inspection. 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”.

Contracted analyses are performed by Pace Analytical Services LLC - Huntersville NC (Certification #12).

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 laboratory is not documenting traceability information for purchased materials
and standards.

Requirement: 15A NCAC 02H .0805 (a)(7)(K) and (g)(7) requires laboratories to have a
documented system of traceability for the purchase, preparation, and use of all chemicals,
reagents, standards, and consumables. That system must include documentation of the
following information: 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: Certificates of Analyses are kept for purchased materials and standards.
However, there was no documentation indicating when these materials and standards were
received and put into use. A receipt log sheet that may be used for documenting traceability
of purchased materials and standards was provided at the time of the inspection.

Proficiency Testing

B. Finding: PT Samples are not being analyzed in the same manner as routine Compliance
Samples.

Requirement: Laboratories are required to analyze an appropriate PT Sample by each
parameter method on the laboratory’s CPL. The same PT Sample may be analyzed by one
or more methods. 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, February 19, 2020, Revision 5, Section 3.6.

Comment: On August 27, 2020, the laboratory analyzed their pH PT sample three times
and reported the average. The laboratory was advised that pH results are not to be
averaged.

Dissolved Oxygen – Hach 10360-2011, Rev. 1.2 (LDO) (Aqueous)

Comment: The laboratory is currently not analyzing any compliance samples for DO. The
established benchsheet does not have spaces to document all required calibration variables.
Calibration documentation must include the instrument identification as well as the temperature, the
elevation or barometric pressure (in mmHg), and the salinity of the sample to be analyzed. Facilities
may use the Salinity default value of zero when calibrating the DO meter unless it is known or
suspected that the Salinity value of the samples being analyzed is > 9 ppt. In those situations, actual
Salinity values must be used. Regardless of which value is used, it must be documented.

Conductivity – Standard Methods, 2510 B-2011 (Aqueous)

C. Finding: The Automatic Temperature Compensator (ATC) check did not meet the
acceptance criterion.

Requirement: Laboratory procedures shall comply with Subparagraph (a)(1) of this Rule.
Ref: 15A NCAC 02H .0805 (g) (4).

Requirement: The ATC must be verified prior to initial use and annually (i.e., 12 months)
thereafter at two temperatures by analyzing a standard or sample at 25°C (i.e., the
temperature to which conductivity values are reported) and a temperature(s) that brackets
the temperature ranges of the environmental samples routinely analyzed. This may require
the analysis of a third temperature reading that is > 25°C (see #3 below). The manner in
which the ATC is verified may depend upon the meter’s capabilities and the manufacturer’s
instructions. The following is one option:

1. Pour an adequate amount of conductivity standard or sample into a beaker or other
container and analyze at 25°C. Document the temperature and conductivity value.
2. Lower the temperature of the standard or sample (e.g., by placing the container in
a refrigerator or ice chest) to less than the lowest anticipated sample temperature and
analyze. Document the temperature and conductivity value.
3. If samples greater than 25°C are to be analyzed, perform the following additional
step: Raise the temperature above 25°C to greater than the highest anticipated
sample temperature (e.g., by placing the container in a hot water bath) and analyze.
Document the temperature and conductivity value.

As the temperature increases or decreases, the value of the conductivity standard or sample
must be within ±10% of the true value of the standard or ±10% of the value of the sample at
25°C. If not, corrective action must be taken. Ref: NC WW/GW LC Approved Procedure for
the Analysis of Specific Conductance (Conductivity).

Comment: The laboratory was performing an annual ATC check but the Conductivity
readings at 35°C and 5 °C were not within the acceptable limit of 10% of the true value of
the standard.

Comment: The laboratory is currently not analyzing any compliance samples for
Conductivity, however, there are some issues that would need to be corrected if they were
to analyze samples in the future. The laboratory was under the assumption that their meter
(Oakton PCTSTestr™ 50) had a standard automatic temperature control for Conductivity.
After discussing the functions of this meter with Oakton Technical Support it was determined
that the automatic temperature control feature listed in the sales literature for this meter was
actually a user-derived temperature compensation factor that is called the Temperature
Coefficient. The default value of the Temperature Coefficient is 2.0% and, according to
Oakton Technical Support, is only useful “within a few degrees” of 25°C. When the
temperature difference is greater than a few degrees they recommend developing “a
baseline that establishes the relationship between temperature and conductivity at or around
the target temperature” for the Temperature Coefficient. When the Temperature Coefficient
is set to 0.0% there is no temperature compensation made to the measured Conductivity

reading. The laboratory was provided with the formula from Standard Methods, 2510 B-2011
(5) (b) for correcting Conductivity according to temperature.

Recommendation: If the laboratory is going to use this meter to analyze compliance
samples for Conductivity, it is recommended that the Temperature Coefficient be set to 0.0%
in order to disable any temperature compensation factor, and to use the temperature
correction formula from Standard Methods, 2510 B-2011 (5) (b) to determine the
Conductivity at 25°C. If this approach is used, an ATC check of the meter would not be
required.

Temperature – Standard Methods, 2550 B-2010 (Aqueous)

D. Finding: The annual temperature-measuring device check procedure is not performed
correctly.

Requirement: Laboratory procedures shall comply with Subparagraph (a)(1) of this Rule.
Ref: 15A NCAC 02H .0805 (g) (4).

Requirement: To check a compliance temperature-measuring device, compare readings at
two temperatures that bracket the range of compliance samples routinely analyzed against a
National Institute of Standards and Technology (NIST) traceable temperature-measuring
device and record all four readings. The readings from both devices must agree within 0.5
ºC. Ref: NC WW/GW LC Approved Procedure for the Analysis of Temperature.

Comment: The laboratory was only analyzing one temperature reading for comparison. The
laboratory is currently not analyzing any compliance samples for Temperature.

IV. PAPER TRAIL INVESTIGATION:

The paper trail consisted of comparing original records (e.g., laboratory benchsheets, logbooks, etc.)
and contract laboratory reports to DMRs submitted to the North Carolina Division of Water Resources.
Data were reviewed for NCSU Lot 86, Industrial Use Permit # WOLFFIN. The following errors were
noted:

Date Parameter Location Value on
Benchsheet Value on DMR
5/1/2020 pH NCSU Lot 86 6.4 S.U. 7.4 S.U.

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: Tom Halvosa Date: November 20, 2020
Report reviewed by: Michael Cumbus Date: November 23, 2020

Certificate Number:5560
Effective Date:1/1/2020
Expiration Date:12/31/2020
Lab Name:Piedmont Geologic P. C.
Address:6003-145 Chapel Hill Road
Raleigh, NC 27607
North Carolina Wastewater/Groundwater Laboratory Certification
Certified Parameters Listing
Date of Last Amendment:11/18/2020
The above named laboratory, having duly met the requirements of 15A NCAC 2H.0800, is hereby certified for the measurement of the parameters listed below.
CERTIFIED PARAMETERS
INORGANIC
CONDUCTIVITY
SM 2510 B-2011 (Aqueous)
DISSOLVED OXYGEN
Hach 10360-2011, Rev. 1.2 (LDO) (Aqueous)
pH
SM 4500 H+B-2011 (Aqueous)
TEMPERATURE
SM 2550 B-2010 (Aqueous)
This certification requires maintance of an acceptable quality assurance program, use of approved methodology, and satisfactory performance on evaluation samples. Laboratories are subject to civil penalties and/or decertification for infractions
as set forth in 15A NCAC 2H.0807.