HomeMy WebLinkAboutNC0020451_CORRESPONDENCE_20030812NPDES DOCUNENT SCANNING COVER SKEET
0
NPDES Permit:
NC0020451
West Jefferson WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Correspondence
Instream Assessment (67b)
Environmental Assessment (EA)
Permit
History
Document Date:
August 12, 2003
0
Z`hia documaxxt i; printecl an reuae pmper - igma re a my
o�]Mte=st C>rm the reYerae aide
o�o� w A r�9Q�
r
E',
Kenneth 'T. NicFadycrt
Town of West Jefferson
Post Office Box 490
Wcstjefferson, NC 28694
Dcar NPD1".S Pertnittcc:
Michael F. Easley, Governor
William G, Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
August 12, 2003
Subject: NPDES Permit NCO020451 i\lerairt Requirement
1 PA Method 1631 / Additional Information
\Vcst Jefferson WW'I'I'
Ashe County
In a previous letter elated !'August 30, 2002, }'our facility was notified of being subject to a new low-level mercury
analysis (F PA Method 1631) for NPDI S monitoring requirements beginning September 1, 2001 The notification
letter was mailed to 155 subject facilities. Since that mailing, the Division has participated in several tNfercury 1631
Workshops to provide the regulated community with information on the new analytical requirements and clean
sampling rccomnlendarions. Based on comments received at these workshops, the following items are intended to
clarify certain NPDE;S requirements for the 155 subject facilities.
1. MerCLIEY SampliriV and Compliance: It is recommended that facilities collect some effluent samples for Method
1631 analysis prior to the 9/l/2003 effective date, in order to gain experience with the recommended clean
sampling techniques as well as the analysts requirements. NPDES compliance will be judged using the new
method results beginning 9/ 1 /2003.
2. What Samples arc Subject to Method 1631: Beginning 9/1/2003, all effluent samples collected for mercury
From the subject facility are requircd to perform low level mercury analysis. This includes effluent samples
collected for any of the following requirements: a) monitoring specified in tour "4ffluent Limitations and
Monitoring Requirements" page of your NPDI_.S permit; b) monitoring specified in your NPDIrS Pretrcatment
Short 'Perm Monitoring Plan (STMP) or Long 'term Monitoring Plan (L'l NIP); and c) NPDL:S permit renewal
requirements. The effluent samples must be analyzed by a laboratory certified by the Division for !Method 1631,
and effluent results must be submitted with the applicable monthly Discharge \tonic>ring Report (D N1R).
3. drab Sampling_ The Environmental Protection Agency (I PA) currently recommends that mcrcury samples for
Method 1631 analysis he collected as grab samples, since automatic composite samplers may he more subject to
contamination. 'Therefore, the Division will allow permittees to collect single grab samples directly into Iab-
provided sample hottics for permit re:cluirements, even though tl,c NPI)EIS permit Inay specify "composite"
samples for mcrcurv. 'Ihc grab sample must be representative of the discharge.
4. Laboratory- Reporting Level: Based on the Division's review of commercial laboratories currently performing
\Method 1631, It majnrity of labs were reporting a minimum level of quantitation (NIL) of either 1.0 ng/l or less.
The Division will requite an NIL, of 1 ng/l beginning 9/ I /2003, which is considered reasonable and economically
achievable.
5. Field Blank Collection: NIcthod 1031 requires that a minimum of one field blank accompany each set of samples
collected From the same site at the same time. The fide] blank is used to identify contamination during sample
collection and transport activities. I F mercury is present in the Field blank at levels that would compromise rchable
measurement ()f mcrcun in the wastewater- sample, you should assume that the effluent sample .vas contaminated
during; collection or transit, and you will need to eliminate any source of contamination that has been identified.
The per-niirtec shall report all effluent saml7le results On the applicable monthly Di1IR. If a field blank fails to
meet quality control criteria, the permittee should note that fact in the IINIR Comments Section, and append the
lab sheet for that field blink. For those: facilities sampling for mercury under a limited monitoring frequency
(quarterly or less, such as Pretrcatment I : NIP/Sl NIP monitoring), S'ou must resamplc if the Field blanks are
outside duality control criteria. I-lo.vever, For those facilities with more frcqucnt effluent nxxaitoring rcquircmcnts
♦*
.r
N. C. Division of Water Duality 1617 Mail Service Center Raleigh, NC 27699-1617 (919) 733-7015 Agi.
Customer Service 1 800 623-7748 NCDEIMR
NPDE:S Mert.ury Rcrluiretnenk
Ptgc; 2 of 2
(i.c., monthly- or more frequent), resampling is not required it field blank quality control criteria are not achieved
for s given sample event. Rcfcr to Mcthod 1631, Revision 1_: (Section 9A.5.2- Quality Control- Ficld Blanks), for
specific quality Control criteria regarding field blank acceptability and effluent sample reliability.
6. Field Blank Subtraction: Mcthod 1631 provides for subtraction of field blanks (provided they meet quality
control criteria defined above) from the effluent sarnplc; result if deemed appropriate bti- a regulatory agency.
Upon rcvieu the Division will not allow field blank subtraction from cfflucnt Samples for reporting purposes.
Based on a recent study using Method 1631 for wastewater samples collected at 38 wastewater treatmenr plants,
Field blank concentrations were generally bcic:rw the method gttarttitation level. Therefore, beginning 9/ 1 /2003,
the permittcc shall report the result Of the effluent sample as provided by the certified lab, without field blank
subtraction, on the monthly D11IR submission. In the event of a mercury limits violation, the pul-nittcc retains
the option to request remission of any penalty. if the permittec believes that the violation resulted from
back�;r()und contamination its indicated by the field blank, the permittcc will need to document that facr with field
blank duality control clata.
7. Sample Preservation/ 1-1 c)ldinV "Times: Samples for total mcrcury analysis by Method 1631 mast be collected in
tightly -capped flUoropolymer or glass bottles and preserved with BrCI or HCI within 48 hours of sample
Collection, The time to sample preservation may be'extcncicd to 28 clays if a sample is oxidized in the sample
bottle. SampiCs must be analyzed within 90 days of sample collection.
1 f yotl have any questie?ns about the contents of this letter, please contact the applicable Division staff listed below:
tNiereury Method:
Certified Labs for Nlethod 1631
NPDfS Permitting:
NPD11S Compliance:
NPD1S Pretreatment.
Roy Byrd
l'rccl Bone
Tom Belnick
Vanessa 1M.-Inuel
Dana Folley
Sincerely,
919-733-3908,-extension 213
919-733-3908, extension 273
919-733-5083, extension 543
919-733-5083, extension 532
919-733-5083, extension 523
Original Signed By
David A Goodrich
Alan W. Klimek, P.1'i.
cc (hardcopy): CLANC, c/o Lew flicks, Environmental Chemist Inc., 6602 Windmill Way, Wilmington, NC 28405
DWQ Rcgional Offices, Water Quality
CC (cm;iil): F'PA Kcgiun 4, Alaclolyn 1]ominy, iNlarshsdl I-tvatt
M Q Water Quality Section; RCgIonal Office Supervisors
13WQ Laboratory Section; Steve Tedder, Larry rlusicy, f im McN,er, Roy Byrd, Fred Bone
DWQ M(Alding/TIMDL, Aliclhclic W(.)Olfolk
DWQ NPDES Compliance, Vancssa Manual
1)W() Pretreatment Unit
DWQ NPDES Unit
NC Leas ue of \lunicipalitics, rlriita Watkins
NC labs Certified for MC1110d 1631c
0�0� vN A769 Michael F. Easley, Governor
William G. Ross Jr., Secretary
y North Carolina Department of Environment and Natural Resources
> Alan W. Klimek, P.E., Director
0 r Division of Water Quality
August 30, 2002
Subject: NPDES Mercury Requirement
Implementation of EPA Method 1631
Dear NPDES Permittee:
Mercury continues to be a water quality concern throughout North Carolina. Fish consumption advisories and
impaired stream segments as a result of elevated mercury levels have been issued for several locations. NPDES
permittees have worked with the state to reduce potential risks from this pollutant, including tasks associated with
collecting and reporting more accurate data. The most commonly used laboratory analysis for total mercury (EPA
Method 245.1) has a method detection level of 0.2 ug/l, while the current water quality standard is an order of
magnitude lower at 0.012 ug/l. Thus, true compliance with the water quality standard could not be judged. A
more recently approved laboratory method (EPA Method 1631) should produce a detection level below the water
quality standard, which would allow the Division to assess potential water quality impacts from dischargers more
accurately. Therefore, this letter serves as notification to your facility that effective September 1, 2003, you will
be required to begin using EPA Method 1631 for subsequent low-level mercury methods approved by EPA in
40 CFR 136) when analyzing for total mercury. Your facility is subject to this new requirement because either 1)
your facility has a current total mercury limit in its NPDES permit that is <0.20 ug/1; or 2) your facility has limited
instream dilution (i.e., the instream waste concentration (IWC) is >6%). This requirement complies with 15 A NCAC
2B.0505(e)(4), which requires that "test procedures must produce detection and reporting levels below the permit
discharge requirements."
Mercury Laboratory Analysis - EPA Method 1631
On June 22, 1999, the US EPA approved a new analytical method (EPA Method 1631) for measuring very low
concentrations of mercury in water. Subsequent revisions to Method 1631 include Revision C (current approved
method) and Draft Revision D (scheduled for promulgation in October 2002). Method 1631 has a minimum level of
quantitation of 0.0005 ug/1 (0.5 ng/1), which is 400-times more sensitive than Method 245.1. The new method
requires a clean laboratory environment which generally requires some lab retrofitting; thus, many permittees will
likely contract a commercial lab to perform the analysis. Based on data compiled by Ohio EPA, commercial labs
that are currently analyzing for EPA Method 1631 charge between $50-90 per sample, with turnaround times
ranging from 5-28 days. Currently there is one commercial lab certified by North Carolina for EPA Method 1631.
However, it is anticipated that several additional labs will also offer this analysis in the future as the demand for
this method increases. When selecting a lab to perform low level mercury analyses, the permittee should review the
lab's performance, experience, and reliability with the method, as well as cost considerations. Attachment A
provides additional information on this method.
Mercury Clean Sampling Techniques - EPA Method 1669
The greatest risk of contaminating the wastewater sample for tow -level mercury analysis is during the sample
collection effort. Thus, those facilities subject to EPA Method 1631 will also need to evaluate clean sampling
recommendations provided in EPA Method 1669. Attachment A provides highlights on this method.
NPDES Compliance
All mercury monitoring data submitted to the Division will be reviewed for compliance with current effluent limits.
If the permit contains monitoring only, the new method must still be used, and the need for a permit limit
will be evaluated at a later date by comparing a statistical evaluation of the effluent data with the water
quality standard and corresponding allowable effluent concentration. Therefore, the potential problem of
sample contamination cannot be overemphasized, since it could result in, NPDES effluent limits for total mercury,
increased monitoring costs, and possibly unnecessary violations. All data submitted to the Division for NPDES
compliance monitoring requirements are the responsibility of the permittee. Therefore, facilities subject to this new
method are strongly encouraged to begin evaluating sampling methods and commercial labs before the deadline
date, to ensure that field staff are properly trained in the use of "clean sampling" techniques, and sampling and lab
procedures are fully developed to minimize sample contamination.
j*A
NCDENR
N. C. Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617 (919) 733-7015
Customer Service 1 800 623-7748
NPDES Mercury Requirement
Page 2 of 3
Additional Information
For additional information and guidance regarding EPA Methods 1631 / 1669, the permittee may consult the
following resources:
North Carolina Division of Water Quality
Laboratory Analysis:
Roy Byrd, 919-733-3908, ext. 213
Lab Certification:
Lab Staff, 919-733-3908
Clean Sampling:
Sandy Mort, 919-733-2136, ext 245
NPDES Permitting:
Tom Belnick, 919-733-5083, ext 543
Pretreatment::
Tom Poe, 919-733-5083, ext 522
US Environmental Protection Agency
Method 1631 / 1669 Questions: Maria Gomez -Taylor, 202-566-1005
EPA Sample Control Center, 703-461-2100
Websites:
http://www.epa.state.oh.us/dsw/guidance/permitIOatt3.t)df
The state of Ohio EPA provides an updated listing of laboratories providing contract services for EPA
Method 1631, including costs, turnaround time, and lab contacts. The labs are identified for informational
purposes only, and do not constitute an endorsement. The listed commercial laboratories may also provide
advice on training, equipment, and sampling techniques appropriate for Method 1631.
http://www.epa.gov/ost/methods/ 1631.html
This EPA site provides information on the 1631 Method requirements and implementation guidance.
htt www.esb.enr.state.nc.us lab
This DWQ site provides information on 'EPA Methods (including 1669 clean sampling techniques), and a
listing of state -certified labs for EPA Method 1631.
http://www.h2o.enr.state.nc.us/NPDES/NPDESweb.html;click Documents
This DWQ website includes a copy of this letter plus a list of facilities currently subject to EPA Method
1631.
Conclusion
The Division realizes that changing the method of mercury measurement will not be without difficulty on the part of
the permittees. The requirement will affect approximately 155 facilities with mercury limits and/or monitoring
requirements. These permittees will need to evaluate available laboratories, costs, and sampling techniques. For
these reasons, the implementation date for EPA Method 1631 was delayed until September 1, 2003, The Division
thanks you for your cooperation and understanding in this matter. If you have any questions about the contents of
this letter, please contact the applicable staff listed above.
Sincerely,
J. William Reid, PE
Supervisor, Point Source Branch
cc (hardcopy): CLANC, c/o Lew Hicks, Environmental Chemistry Inc., 6602 Windmill Way, Wilmington, NC 28405
cc (email): EPA Region 4, Marshall Hyatt, Scott Gordon, Roosevelt Childress
DWQ Water Quality Section; Coleen Sullins, Regional offices
DWQ Laboratory Section; Steve Tedder, Larry Ausley, Jim Meyer, Roy Byrd, Connie Brower
DWQ Aquatic Toxicology Unit, Sandy Mort
DWQ Pretreatment Unit, Tom Poe
DWQ Modeling/TMDL, Michelle Woolfolk
DWQ NPDES Compliance Unit, Shannon Langley
DWQ NPDES Unit
MCIC, Michael Johnson
NC League of Municipalities, Paula Thomas
Clean Water Fund of NC, Hope Taylor
Severn Trent Lab, Ohio, Mark Bruce
NPDES Mercury Requirement
Page 3 of 3
ATTACHMENT A
Summary of EPA Methods 1631/ 1669
Effluent samples collected for mercury may become contaminated by numerous routes, including: 1) metal -
containing labware, reagents, containers, and sampling equipment; 2) improperly cleaned or stored equipment; and
3) atmospheric mercury inputs in dirt and dust. Even human contact can be a source of mercury contamination
(e.g., mercury amalgam fillings in the mouths of lab/field personnel can contaminate samples directly exposed to
exhalation). Thus, it is essential that every effort be made to minimize sample contamination during collection. The
US EPA provides recommendations to minimize contamination during sample collection in EPA Method 1669:
Sampling Ambient Water for Determination of Trace Metals at EPA Water Quality Criteria Levels. This guidance
describes a "clean hands/dirty hands" sampling technique to collect mercury samples, which is ideally performed
with two people. A designated "clean hands" sampler handles all operations involving direct contact with the
sample bottle, while the "dirty hands" sampler is responsible for all activities that do not involve direct contact with
the sample bottle. This team sampling technique is recommended as a means to minimize sample contamination,
but is not required. The US EPA is developing a trace metal sampling guidance strictly for effluent collection
(Method 1670). The permittee will need to evaluate the various sampling recommendations and develop a sampling
strategy appropriate for their particular situation. The overall philosophy behind any mercury sampling strategy
should be to ensure that any object or substance that contacts the sample is nonmetallic and free from any
material that may contain metals, in order to produce a reliable mercury measurement.
Requirements and recommendations for EPA Method 1631
and clean sampling for low level mercury include:
■ It is strongly recommended that the permittee discuss sample collection, preservation, and shipping
requirements with their laboratory, to ensure that the most current requirements of Method 1631 will
be met. There have been several revisions to EPA Method 1631, and Revision D is proposed.
■ Each laboratory must perform and meet the minimum requirements of Method 1631 Quality Control.
■ Effluent samples for mercury analysis must be collected in clean fluoropolymer or borosilicate glass
containers. It is recommended that the permittee request appropriate clean sample bottles or a
mercury sampling kit from their lab.
■ Method 1631 requires that a minimum of one field blank accompany each set of samples collected at a
given site. The field blank is used to identify contamination from sample collection and transport. If
mercury is present in the field blank at levels that would compromise reliable measurement of mercury
in the wastewater sample, you should assume that the sample was contaminated during collection or
transit, and you will need to eliminate any source of contamination that has been identified and
possibly resample. Including the field blank, the permittee should budget for two samples per
monitoring event.
• Samples must be preserved or analyzed within 48-hours after collection. Samples do not need to be
refrigerated/iced during shipment provided they are tightly capped, shipped overnight to the lab, and
preserved or analyzed by the lab within 48 hours of collection (per Draft Revision D).
■ If the samples are preserved within 48 hours, then they have a maximum holding time of 90 days prior
to analysis (per Draft Revision D).
• Sampling personnel must wear clean, non -talc latex gloves during sample collection and handling.
■ EPA currently recommends that mercury samples for Method 1631 analysis be collected as grab
samples, since automatic composite samplers may be subject to contamination and loss of mercury via
volatilization. Therefore, the Division will allow permittees to collect single grab samples directly into
lab -provided sample bottles for permit requirements. The grab sample must be representative of the
discharge.
■ If the person collecting the sample cannot directly reach the wastewater stream, a pole -type sampler
may be attached to the sample bottle to extend the reach for sample collection. The pole and bottle
clamp should be made of plastic and/or stainless steel and the mouth of the bottle should be held
facing upstream of the pole. The use of a transfer vessel should be avoided.
• All sampling equipment must be nonmetallic, or free of material that may contain metals. All materials
that will directly or indirectly contact the sample must be cleaned using the procedures in Method
1631.
• To minimize atmospheric contamination, do not sample during rainy weather or when the wind could
blow dust particles into the sample bottle. To minimize human contamination, do not breathe into the
sample bottle if you have mercury amalgam fillings in your teeth.
■ Sampling personnel should be trained in techniques for sampling mercury at low levels. Sample
collection via the "clean hands/dirty hands" technique is recommended, but not required.
• Since Method 1631 is performance -based, there is some flexibility in Method requirements.