HomeMy WebLinkAbout#68 10-final
INSPECTION REPORT ROUTING SHEET
To be attached to all inspection reports in-house only.
Laboratory Cert. #: 68
Laboratory Name: Unifi, Inc. – Reidsville
Inspection Type: Industrial Maintenance
Inspector Name(s): Jeffrey R. Adams
Inspection Date: September 30, 2010
Date Report Completed: October 18, 2010
Date Forwarded to Reviewer: October 18, 2010
Reviewed by: Todd Crawford
Date Review Completed: October 20, 2010________
Cover Letter to use: Insp. Initial X Insp. Reg. Insp. No Finding Insp. CP
Unit Supervisor: Dana Satterwhite
Date Received: October 20, 2010
Date Forwarded to Alberta: November 29, 2010
Date Mailed: November 29, 2010
_____________________________________________________________________
On-Site Inspection Report
LABORATORY NAME: Unifi, Inc. - Reidsville
NPDES PERMIT #: NCG170176
ADDRESS: P.O. Box 1437
Reidsville, NC 27323-1437
CERTIFICATE #: 68
DATE OF INSPECTION: September 30, 2010
TYPE OF INSPECTION: Industrial Maintenance
AUDITOR(S): Jeffrey R. Adams
LOCAL PERSON(S) CONTACTED: Lisa Haynes and Darlene Moore
I. INTRODUCTION:
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:
Mr. Mike Thomas, with the North Carolina Division of Water Quality (NCDWQ) Winston-Salem Regional
Office was in attendance to observe a portion of the audit.
The laboratory was neat and equipment was well maintained. Records were well organized, however,
some quality control procedures need to be implemented. The laboratory filed an Amendment to
Certification Application with the inspector during the audit and COD HACH Method 8000 has been
removed from the laboratory’s certificate attachment.
The laboratory was given a packet containing North Carolina Laboratory Certification quality control
requirements and policy changes during the inspection.
Finding A is a new policy that has been implemented by our program since the last inspection.
III. FINDINGS, REQUIREMENTS, COMMENTS AND RECOMMENDATIONS:
Documentation
Recommendation: It is recommended that the laboratory review Standard Operating Procedures
(SOPs) periodically. Since there are often changes in technology or options within a particular method
that are not covered in published references the laboratory SOP is the prescriptive reference document
that describes a laboratory’s analytical procedure in detail. This document is intended to be the
reference for analysts performing the specified test procedure. Please review laboratory SOPs and
update as necessary to ensure that: The method is being performed as stated, references to standard
methods are correct, the SOP is in agreement with approved practice and regulatory requirements.
Copies of the most current versions of SOPs must be readily available to the analyst(s).
A. Finding: The laboratory needs to increase the documentation of purchased materials and
reagents, as well as, documentation of standards and reagents prepared in the laboratory.
Page 2
#68 Unifi, Inc. - Reidsville
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: North
Carolina Wastewater/Groundwater Laboratory Certification Policy.
Biochemical Oxygen Demand – Standard Methods, 18th Edition, 5210 B
B. Finding: The laboratory is not checking for total residual chlorine prior to sample analysis.
Requirement: If possible, avoid samples containing residual chlorine by sampling ahead of
chlorination processes. If the sample has been chlorinated but no detectable chlorine residual is
present, seed the dilution water. If residual chlorine is present, dechlorinate sample and seed
the dilution water (¶ 4f). Ref: Standard Methods, 18th Edition, 5210 B. (4) (e) (2). See attached
document titled, Neutralizing Total Residual Chlorine in BOD Samples, for additional
information.
C. Finding: Dilution water was not prepared according to method instructions.
Requirement: Place desired volume of water in a suitable bottle and add 1ml each of
phosphate buffer, MgSO4, CaCl2, and FeCl3 solutions/L of water. Ref: Standard Methods, 18th
Edition, 5210 B. (4) (a).
Comment: HACH nutrient pillows are added to the dilution water which contains all of the
necessary nutrients required by the method, but an additional amount of phosphate buffer is
also added. This exceeds the amount of phosphate buffer required in the method.
pH – Standard Methods, 18th Edition, 4500 H+ B
D. Finding: The annual NIST temperature sensor check is being performed but the process is not
properly documented.
Requirement: All thermometers must meet National Institute of Standards and Technology (NIST)
specifications for accuracy or be checked, at a minimum annually, against a NIST traceable
thermometer and proper corrections made. Ref: 15A NCAC 2H .0805 (a) (7) (O).
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. The quality
control document shall be available for inspection by the State Laboratory. Ref: 15A NCAC 2H
.0805 (a) (7).
Recommendation: It is recommended that the date the sensor check is performed, analyst initials
and any correction (even if zero) be posted on the meter, as well as, retained in hard copy format.
Total Suspended Residue – Standard Methods, 18th Edition, 2540 D
Page 3
#68 Unifi, Inc. - Reidsville
E. Finding: A minimum dried residue weight gain of 1 mg is used to determine the reporting limit.
Requirement: Choose sample volume to yield between 2.5 and 200 mg dried residue. If
volume filtered fails to meet minimum yield, increase sample volume up to 1 L. If complete
filtration takes more than 10 minutes increase filter diameter or decrease sample volume. Ref:
NC WW/GW LC Policy based upon Standard Methods, 20th and 21st Editions, 2540 D. (3) (b).
Comment: Since the publication of the March 12, 2007 Code of Federal Regulations; 40 CFR
Part 136; Vol. 72, No. 47, there is no longer an approved method that allows for a 1 mg weight
gain. Currently the minimum weight gain allowed is 2.5 mg. In instances where the weight gain
is less than the required 2.5 mg, the value must be reported as less than the appropriate value
based upon the volume used. For example, if 500 mL of sample is analyzed and < 2.5 mg of dried
residue is obtained, the value reported would be < 5 mg/L. The minimum reporting value is now
established at 2.5 mg/L based upon a sample volume used of 1000 mL.
F. Finding: The temperature of the drying oven used in the analysis was not within the
acceptable range.
Requirement: Dry for at least 1 hour at 103 to 105°C in an oven, cool in a desiccator to
balance temperature, and weigh. Ref: Standard Methods, 18th Edition, 2540 D. (3) (c).
Comment: The inspector noticed the drying oven temperature to be 100.5°C, yet all earlier log
book recordings showed the temperature to be ≥103°C. The temperature was again observed
after 30 minutes and still remained 100.5°C, indicating the oven temperature needed adjusting
to the required temperature. Oven temperatures must be allowed to equilibrate to the proper
temperature range before the measured drying time begins. At that point, the actual observed
temperature must be recorded in log books to demonstrate method requirements have been
met. Recording a “≥” number is not acceptable.
IV. PAPER TRAIL INVESTIGATION:
The paper trail consisted of comparing laboratory benchsheets and contract lab reports to Periodic Self-
Monitoring Reports (PSMRs) submitted to the Town of Reidsville, NC. Data were reviewed for Unifi,
Inc., Reidsville, NC (Stormwater discharge permit #NCG170176) for the following months: March, May,
and July, 2010. No transcription errors were detected. It appears the laboratory is doing a good job of
accurately transcribing data.
V. CONCLUSIONS:
Correcting the above-cited findings and implementing the recommendations will help this lab 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.
Report prepared by: Jeffrey R. Adams Date: October 18, 2010
Report reviewed by: Todd Crawford Date: October 20, 2010
Neutralizing Total Residual Chlorine in BOD Samples
It is acceptable to screen samples with DPD powder for the presence of Total Residual Chlorine (use
pillows appropriate for the volume of sample tested). Generally total residual chlorine test strips are not
adequate; however, these may be used for samples where interference with DPD precludes their use. If
DPD yields no pink color, chlorine is absent. Document and proceed to set sample. If pink color is
observed, chlorine is present. In those cases, the titration procedure outlined below must be used to
determine the proper amount of Sodium Sulfite needed to neutralize chlorine in the sample.
Chemicals:
1. Sodium Sulfite solution - Dissolve 0.1575 g Na2SO3 in 100 mL distilled water. Prepare fresh
daily.
2. 2% H2SO4 - Add 2 mL concentrated H2SO4 to 100 mL distilled water.
3. Potassium Iodide (KI) solution - Add 10 g KI to 100 mL distilled water. Initially this solution will
be clear, but in a few days it will turn greenish yellow. That’s ok.
4. Starch - Commercially available or see Standard Methods, 20th Edition - Method 4500-O C. (2)
(d).
Procedure:
To 100 mL of sample, add approximately 1 mL of 2% H2SO4, 1 mL KI solution, and 1 mL starch.
If the solution remains clear, no chlorine is present. Document this on the bench sheet and proceed to
set up the sample for BOD analysis.
If the solution turns blue, chlorine is present. Add the Sodium Sulfite solution, drop by drop, while
stirring the sample, until the sample is clear again. Count the drops of Sodium Sulfite solution needed
to neutralize the 100 mL sample. Add the relative volume of Sodium Sulfite solution to the volume of
sample needed. For example, if it took 6 drops to neutralize the 100 mL sample volume and you need
300 mL of sample to set the dilutions you want, add 18 drops of Sodium Sulfite solution to 300 mL of
sample. Document this on the bench sheet. Wait about 15 minutes and recheck the sample to verify the
chlorine has been neutralized. Proceed to set up the sample.
Note: If the blue color returns after a few seconds, do not add more Sodium Sulfite solution. Recheck
with DPD to verify that returning blue color is not caused by chlorine still in sample. If no chlorine is still
present, add amount of Sodium Sulfite solution equivalent to when blue color first disappears. Adding
an excessive amount of Sodium Sulfite solution creates an oxygen demand and will result in a false
high BOD value.