NC0020559_Historical_1999

ity of Henderson Office of
P. O. Box 1434 City Manager
180 Beckford Drive Eric M. Williams
Henderson, NC 27536
ewilliams@ci. henderson. nc. us
Phone:[phone] Fax:[phone]
September 22"d, 1999
(hand delivered this date)
Mr. Ken Schuster
Regional Supervisor Z
Raleigh Regional Office S'
Department of Environment
and Natural Resources
1628 Mail Service Center
Raleigh, North Carolina 27699-1628
RE: Additional Meeting Confirmation (Thursday, September 23rd, 10:30 a.m.)
and Background Information and Justification
relative to a one year extension request to achieve full and complete
compliance with Chronic Toxicity Requirements
Special Order by Consent EMC WQ No. 96-05 —
City of Henderson and NCDENR
Dear Mr. Schuster:
I am writing to briefly confirm (again) our scheduled meeting in your Offices
on Thursday, September 23rd, at 10:30 a.m. to generally review the status of our
wastewater treatment program and to specifically seek your support in granting a
one year extension to the section of our SOC requiring "full and complete
compliance" with chronic toxicity by September 30th of this year. As you know
(from my most recent letter of September 17th) we failed our September Toxicity Test at
77.9%.
As you are aware, we have had regular communication on this issue, and others,
for quite some time and I believe our request is not only justified, but in the best
interest of both the State and the City of Henderson. In this regard we have
carefully reviewed not only our extensive efforts to date in our waste treatment program
generally (and specifically with respect to toxicity), but also we have attempted to
familiarize ourselves with the Department's rules respecting Consent Orders and the
criteria associated therewith.
IIADMIMDWHITEVetters1schuster9-22-99.doc Page 1 of3

Accordingly, you will find the following Exhibits attached:
Exhibit I A brief recap and statement from our Independent Consultant (Aquatic
Sciences Consulting) with respect to several of the standards described in
15A-2H.1206(b)(1), Evaluation of Requests, and
Exhibit II Further background information and justification, dated September 22"d
1999, detailing a variety of both historical and current data which should
be useful to the State in analyzing our request. The following sections and
categories are provided within this Exhibit.
A) Historical Background of the Treatment Facility
B) Compliance with Additional NPDES Permit Requirements and
Toxicity Reduction Efforts (incl. costs)
C) Progress Achieved in Toxicity Reduction Evaluation (TRE)
D) Toxicity Reduction Evaluation (TRE) Plan during one year
Extension
E) City Standard Chronic Toxicity Monitoring and Special Conditions
for Industrial Dischargers
F) Current Plans and Cost Data — Proposed Master Plan
Improvements to Nutbush Creek Wastewater Treatment Plant —
from McKim & Creed Study and Analysis
While we realize this information is quite lengthy, most of it is familiar to you
and/or your staff, however, we felt the compilation of this information formatted in
this manner would prove useful in our discussions and be of help to you as we
seek your support (we trust) in our one year extension request.
IODMIN DK"ITE$Vetterslschuster9-22-99.doc Page 2 of 3

As always, we appreciate your time and consideration in meeting with us and
I'll look forward to seeing you, along with other members from our staff, at our meeting
this coming Thursday morning. Until then, please accept my very best regards.
Sincerely,
CITY OF HENDERSON
Zlliams
ager
EMW/dew
C: Mr. Mark Warren, Assistant Manager
Mr. Tom Spain, WWTP Director
Mr. Reggie Hicks, Pre -Treatment Coordinator
Mr. H. Glen Dunn, Esq., Poyner & Spruill
Mr. John A. Botts, Aquatic Sciences Consulting (via fax: [phone])
Mr. John Z. Zollicoffer, Jr., City Attorney
* Faxed copy only — original will not follow
lI4DMINIDWHITE$Vetterslschuster9-22-99.doc Page 3 of 3

EXHIBIT I
Aquatic Sciences Consulting 15751 Bushy Park Rd
Woodbine, Maryland 21797
[phone] —phone
[phone] — fax
21 September 1999
Mr. Eric Williams
City Manager
City of Henderson
180 Beckford Dr
Henderson, NC 27536-1434
Re: Demonstration of Toxicity Treatment Performance at the City of Henderson's Nuthush
Creek Wastewater Treatment Plant
Dear Mr. Williams:
Aquatic Sciences Consulting (ASC) has reviewed the treatment performance of the City's
Nuthush Creek Wastewater Treatment Plant (WWTP) in support of the request for extension of
the Special Order of Consent (SOC). In January 1997, an independent review of the WWTP
was performed to evaluate treatment performance and to identify measures that could be taken to
improve toxicity reduction at the WWTP plant. In general, the review found that the WWTP
was being operated within standard design and operating specifications. Several
recommendations were made and acted upon to attempt to further optimize the WWTP
performance with respect to toxicity removal. In addition, the City subsequently evaluated
additional options for toxicity treatment. A description of the WWTP optimization is included
in the materials appended with this letter.
The following is a summary of the actions taken by the City to optimize the treatment of toxicity
at the existing WWTP.
As recommended in the 1997 consultant report, the City evaluated the toxicity reduction
capability of the major unit processes at the WWTR The results of this evaluation are
noted in the appended summary of THE progress. In summary, toxicity is reduced through
the trickling filters, but little or no removal occurs in the activated sludge process. The lack
of toxicity removal may be related to the type of toxicant. Some toxic surfactants can
break down to more toxic compounds during treatment.
As recommended in the 1997 consultant report, the City has rehabilitated the trickling filter
process to increase the wastewater contact time with the trickling filter media. This
increased contact time optimizes the removal of biodegradable toxicants.
As recommended in the 1997 consultant report, the City increased the mixed liquor
suspended solids (MLSS) concentration in the activated sludge process to the maximum
practical level. MLSS concentrations are maintained as high as possible to optimize the

Mr. Eric Williams
City of Henderson
Page 2
21 September 1999
treatment of biodegradable toxicants.
• As recommended in the 1997 consultant report, the City has evaluated different mean cell
residence times (MCRTs) for enhancing toxicity reduction. The current sludge age of 18
days achieves optimum removal of BOD and ammonia. Optimizing removal of these
pollutants should optimize removal of biodegradable toxicants.
• As recommended in the 1997 consultant report, the City has computerized the process
control data for easy access and review.
• As recommended in the 1997 consultant report, the City has intensified its pretreatment
program efforts. These efforts include permit requirements for toxicity, frequent
inspections, chemical usage reviews, and preparation of chemical optimization plans for
each permitted industrial user.
• In treatability testing, the City found that hydrogen peroxide (HZO,) reduces effluent
toxicity. The City implemented H2O2 treatment within a few months of the tests and
monitoring results have shown that toxicity is reduced by four to five -fold.
• The City is currently evaluating (1) toxicity reduction by activated carbon and (2) the
degree of toxicity treatment that could be achieved by a planned activated sludge process
upgrade. Recent results of carbon isotherm testing suggest that carbon will remove toxicity.
The City is currently investigating the feasibility of adding carbon treatment at the WWTP.
Again, the City has implemented the recommendations of the 1997 WWTP review and
additional changes have been made since then to optimize toxicity reduction. It is my opinion
that noncompliance with the toxicity limit is not due to "failure by the permittee to properly
operate, manage, and maintain the wastewater treatment system (15A-2H.1206 (b) (1)". Also, I
believe that the existing WWTP is being operated in such a way as to "attain the highest degree
of [toxicity] treatment possible under the existing conditions (15A-2H.1206 (b) (1)". I further
believe that the city has evaluated "all reasonably available low -capital -cost interim
improvements for toxicity reduction (15A-2H.1206 (b) (1)".
Sincerely,
John A. Botts
Principal Scientist
N]iII VKSVj01

Mr. Eric Williams
City of Henderson
Page 3
21 September 1999
Aquatic Sciences Consulting

EXHIBIT 11
Background Information
September 22"a
and Justification
1999
Request from the City of Henderson
for
One Year Extension
Toxicity Requirements of Special Order by Consent
(EMC WQ No. 96-05)
Submitted To
Raleigh Regional Office
Department of Environment & Natural Resources

A) HISTORICAL BACKGROUND OF THE TREATMENT FACILITY
The City of Henderson originally operated two wastewater treatment
plants called the Nutbush Creek Plant and the Redbud Creek Plant. The
Nutbush Creek Plant was built in the late 1930's to provide primary
treatment and later in 1962 was upgraded to provide secondary treatment for
wastewater with an average daily flow of 1.84 million gallons and an
organic (SODS) loading of 4,680 pounds per day. The plant included
preliminary treatment, primary clarification, high -rate trickling filter
system, chlorination, anaerobic sludge digestion, and sand beds for sludge
dewatering. The Redbud Creek plant was built in 1962 to provide secondary
treatment for wastewater with an average daily flow of 0.24 million gallons
and organic (SODS) loading of 480 pounds per day. The plant also included
preliminary treatment, primary clarification, high -rate trickling filter
system, chlorination, anaerobic sludge digestion, and sand beds for sludge
dewatering.
In May, 1974 the 201 Facilities Plan recommended two separate
treatment plants - one on Sandy Creek and another on Nutbush Creek, was
submitted to the NC Division of Environmental Management and Environmental
Protection Agency for approval. In February, 1975 the NCDEM certified the
201 Facilities Plan for EPA. However, in June, 1975, due to opposition to
the proposed plant's discharge to Sandy Creek, EPA and NCDEM issued notice
of intent to prepare an Environmental Impact Statement. In December, 1975,
under EPA contract, Radian Corporation of Austin, Texas, initiated
preparation of an Environmental Impact Statement for wastewater treatment
facilities for the Henderson 201 Facilities Planning Area.
In response to an EPA request of June, 1975, the 201 Facilities Plan
was revised and submitted to NCDEM and EPA in January, 1976 for approval.
In the revised Facilities Plan, after evaluating seventeen (17)
alternatives, the Alternative Plan No. 2B (two plants - one on Sandy Creek
and another on Nutbush Creek) was recommended to provide for the wastewater
treatment needs of the Henderson 201 Facilities Planning Area.
In November, 1976, EPA published the Draft EIS in which the
Following three alternatives were selected for final consideration:
Alternative A: Abandon the Redbud Creek Wastewater Treatment Plant and
pump the tributary wastewater to a new plant to be
constructed on Sandy Creek upgrade the existing Nutbush
Creek Plant with a capacity of 1.58 MGD with odor control
and phosphorus removal; construct a 2.12 MGD wastewater
treatment plant on Sandy Creek.
Alternative B: Abandon Nutbush Creek and Redbud Creek Wastewater
Treatment Plants; construct a new 3.70 MGD plant on Sandy
Creek.
Alternative C: Abandon the Redbud Creek Wastewater Treatment Plant and
pump the tributary wastewater to the Nutbush Creek plant;
upgrade and expand the Nutbush Creek Plant to 3.70 MGD
with odor control and phosphorus removal.

In November, 1977 EPA published the Final EIS. Based upon the review of
the final environmental and cost evaluation of the three alternatives
considered in the Draft EIS, EPA, with the concurrence of the NCDEM,
selected the Alternative C as the most cost-effective and environmental
sound alternative for the Henderson 201 Planning Area.
In 1978, the plans and specifications for upgrading and expansion of
Nutbush Creek Plant to 4.14 MGD were prepared and contracts were awarded
in November, 1979 for construction of the project. It should be noted that
the change in design flow from 3.70 MGD to 4.14 MGD was due to the findings
of the revised Infiltration/Inflow Analysis. The upgrading and expansion
work of the Nutbush Creek plant was completed in 1981.
The upgrading and expansion of the Nutbush Creek Plant in 1981, at a cost
of $10,000,000 still did not bring the plant into compliance with its NPDES
(National Pollution Discharge Elimination System) permit. The Treatment
Plant did an excellent job of treating the sewage from April through
November, but would experience severe problems with treatment during the
cold wet winter months of December through March. Cold temperatures
combined with excessive flows entering the plant during rainfall and/or
snow would wash the bacteria needed to treat the sewage out of the
treatment plant. This pattern of being in non-compliance with permit
limits of BOD and Ammonia Nitrogen during the winter months continued until
October, 1987.
Following these events, the City of Henderson entered into a Special Order
by Consent (SOC) with the North Carolina Division of Environmental
Management. The SOC was converted to a Complaint and Consent Judgement
(JOC) in June, 1988. The JOC was issued by the North Carolina Superior
Court System. Under this Order, the City of Henderson was issued less
stringent permit limits for the wastewater treatment plant to allow the
plant to be in compliance until it was upgraded. The JOC set specific
activities and deadlines that the City must abide by, or face fines up to
$500.00 per day.
Two (2) new clarifiers were constructed at the treatment plant and put into
service in November, 1990. This was done to enable the plant to retain the
bacteria used for sewage treatment during periods of cold weather and high
flows. The new final clarifiers brought the plant into compliance with
Ammonia -Nitrogen and BOD limits, but the City remained under a JOC because
of new permit limits issued in 1990 that the plant is unable to meet.
The JOC also required that the City enforce the water conservation
provisions of the State Building Code, test and limit the amount of waste
that industries are allowed to discharge to the treatment plant, and
continue to rehabilitate old sewer lines that allow excessive
inflow/infiltration to enter the treatment plant during periods of
rainfall.
A new 1,000,000 gallon Sludge Holding Tank was constructed and put in
service in November, 1990. This extra storage capacity allows the Nutbush
Plant to meet the new EPA regulation requiring 60 day sludge holding time
to reduce pathogens before applying the sludge to agricultural land.

New permit limits issued by the North Carolina DEM in October, 1990
required additional plant construction to remove Phosphorus, Toxicity,
Metals, Fecal Coliform, and Residual Chlorine.
Renovation of the tertiary filtration system, construction of an alum
system, an aerobic sludge digester, an ultraviolet disinfection system, and
expansion of the laboratory were completed in November, 1994. The
upgrade/construction of these systems brought the Plant into compliance
with the new regulations except chronic toxicity in December, 1994 (Note:
Mercury and MBAS problems surfaced in 1994 and were solved by 1996).
Chronic toxicity is being addressed with the help of a private firm
(Aquatic Sciences Consulting, Woodbine, MD) to identify the cause(s) and
to assist the City in correcting the problem(s). The construction cost of
these systems was $3.5 million.
The present SOC resulted from conversion from the JOC to the SOC in 1998.

B) COMPLIANCE WITH ADDITIONAL NPDES PERMIT REQUIREMENTS
AND TOXICITY REDUCTION EFFORTS (INCL. COSTS)
The City had the following limits and monitoring requirements added to the Nutbush
Creek WWTP NPDES Permit between 1990 and 1994.
PARAMETER
LMM
FECAL COLIFORM (LOWER)
200/400
RESIDUAL CHLORINE
0.017 MG/L
PHOSPHOROUS
1.011.5 MG/L
CHROMIUM
0.050 MG/L
LEAD
0.026 MG/L
CADMIUM
0.0021 MG/L
NICKEL
0.091 MG/L
MBAS
0.516 MG/L
MERCURY
0.000017 MG/L
FLUORIDE
1.8 MG/L
CHRONIC TOXICITY
90%
ZINC
MONITOR ONLY
CHLORIDE
MONITOR ONLY
COPPER
MONITOR ONLY
SILVER
MONITOR ONLY
CYANIDE
MONITOR ONLY
IRON
MONITOR ONLY
CONDUCTIVITY
MONITOR ONLY
The City's Nutbush Plant was able to come into compliance by 1996 with all of the new
permit parameters except Chronic Toxicity as a result of the following actions:
1. Three positions were added to the staff (1 Assistant Chemist, 1 Laboratory
Technician, and 1 Operator).
2. Ferrous Sulfate addition was started at two (2) pump stations, which controlled
hydrogen sulfide and brought the plant into compliance with phosphorous limits.
(Average annual costs equal $80,000)
3. The new ultraviolet disinfection system resulted in compliance with the new 200
Fecal Coliform limit and eliminated any toxic effect of residual chlorine.
4. The replacement of the tertiary filter media helped to lower BOD, TSS, and
N133-N considerably below permit limits.
5. The water plant discontinued use of zinc phosphate as a corrosion inhibitor in the
distribution system, which lowered level in the WWTP effluent.
6. The City has worked very aggressively with the Significant Industrial Users to
eliminate contaminants entering the WWTP.
Winstead's Radiator Shop installed a closed loop system and eliminated our
violation of lead limits and also lowered copper limits.

8. Americal Corporation modified their pretreatment system and added two (2)
dissolved air floatation units, which lowered their discharge limits of BOD, COD,
TSS, TKN, Dye Color, Oils and Surfactants. This helped bring the treatment
plant into compliance with MBAS and initial tests show a toxicity reduction in
Americal's discharge.
9. Kenametal installed a pretreatment system to recover Lacoline and eliminated the
use of a very toxic Aluminum Bright cleaner.
10. Burkhart discontinued use of a Blue Dispersant as soon as it was tested and found
to be toxic.
11. Hydrogen Peroxide feed in the plant effluent was begun in February 1997 and is
still in use today to reduce toxicity. (Average annual costs equals $15,000)
12. The City inspected all of the Significant Industrial Users with a staff member of
the Pollution Prevention and Environmental Assistance Section of the Department
of Environment and Natural Resources to encourage minimization of chemical
usage and optimization of processes.
13. Iams Inc. had their facility evaluated by a private engineer and were able to come
into compliance with zinc levels by changing their clean up procedures.
They are presently under a Consent Order to develop a process to lower their
phosphorous discharge.
14. The City is using a Micro-tox Unit in-house to identify toxic samples rapidly.
This is allowing more analyses of locations, which should help locate viable
toxicity.
15. An in-house pilot plant test is being operated at the design aeration time of the
proposed new plant. The treatability of toxic samples can now be evaluated
through this system to see if toxicity is eliminated.
16. Preliminary treatment of toxic samples with activated carbon indicated removal of
toxicity.
17. The City has used three (3) different consulting firms in the past two (2) years to
assist in toxicity reduction studies at the WWTP and industries.

FY 1996-97
E&A
and
$18,330.81
January and February (John Botts 1 $1,147.87
Burlington Research THE
July
$4,191.88
July Acute TRUM
$5,852.00
August
$1,174.88
August TCLP S
$5,250.00
September
$2,683.76
October
$3,422.85
November
$2,519.88
December
$1,793.13
January
$544.35
February
$1,441.15
February THE Special Testing
$7,427.53
March
$2,042.50
April
$1,531.88
May
$1,884.50
June
$760.00
Total
$42,520.29
Project Fees
July
$2,650.00
August
$3,745.25
September
$4,895.45
October
$4,750.15
November
$1,743.75
December
$1,502.50
January
$5,359.30
February
$3,650.55
March
$2,257.50
April
$1,080.00
May
$3,293.95
June
$663.75
Total
$35,592.15
TOTAL FOR YEAR
$97,591.12

THE FY 1997-98
E & A Engineering
May and June $10,900.00
Aquatic Engineering
July
$3,000.00
July
$1,500.00
August (Chem. Opt. Plan)
$850,00
August
$2,500.00
August
$4,870.00
September
$1,600.00
Oct — Feb
$1,675.00
February and March
$2,860.00
June
$3,722.00
June
$2,942.00
Total
$25,519.00
Burlington THE
July
$3,572.00
August
$2,327.50
September
$7,600.00
October
$771.88
November
$747.25
November — Metals
$2,136.00
December
$1,654.00
February
$1,353.00
March
760.00
Total
$20,921.63
Burlington Project
Fees
July
$3,071.63
August
$2,971.25
September Phase II TIE Test
$1,567.50
September
$1,723.75
October
$1,053.75
November
$1,681.25
January
$1,912.50
February
$3,301.70
Total
$17,283.33
Total Burlington Research
$38,204.96
Microtox Supplies
$6,628.52
Lab StaffHours 932 @ $14.85
13,840.20
Total
TOTAL
05,092.64

FY 1998-99
Aquatic Sciences
July — August
$2,335.60
August - November
$3,314.79
November — December
$3,534.56
February — May
$3,360.00
March — June
$3,850.00
April — June
$6,480.00
Total
$22,874.95
Tritest
October
$700.00
December
$800.00
January
$700.00
February
$700.00
March
$700.00
April
$700.00
May
$700.00
June
$1,500.00
Total
$6,500.00
E & A Engineering
July
$900.00
August
$5,500.00
September
$780.00
November
$1,940.00
February
$1,520.00
March
$690.00
April
$4,508.00
May
$5,538.00
June
$1,560.00
Total
$22,936.00
Microtox Supplies
$4,576.83
Lab Staff Hours 432 @ $14.85
$6,415.20
Temporary Employee 1099.75 hrs @
$11.66
$12,823.08
TOTAL
$76,126.06

FY 1999-2000
Aquatic Sciences
July - September $12,702.00
Tritest
July - September 1$3,780.00
Lab Hours
July - September 185 hours @ 14.85 = $1,262.25
Total for 1999-2000 $17,744.25

Aside from the City's consultant expenditures previously outlined, one of the City's industrial
dischargers (Amedcal) has incurred, during 1999 alone and exclusive of any related costs
prior to that time (for consultation and/or capital expenditures) the following costs as
provided by Aquatic Sciences Consulting:
AMERICAUS 1999 THE COSTS
1999 Invoices
Americal
Invoice
Date Invoice # Amount
6-Feb
1033
$5,675.00
18-Mar
1041
$8,540.00
20-Apr
1042
$2,495.00
5-May
1045A
$1,750.00
9-Jun
1048
$2,405.00
11-Aug
1064
$4,175.00
21Sep
1069
$3,456.001
Total $28,495.00

C) PROGRESS ACHIEVED IN TOXICITY REDUCTION EVALUATION
(TR')
This summary of THE progress focuses on the city's intensive efforts in the past three
years. As described, the city has identified and eliminated three sources of toxicity. A
fourth source of toxicity is being evaluated. Source identification has required the
development of alternative THE methods at considerable expense to the city because
EPA's THE procedures were incomplete. In addition, the city is evaluating toxicity
treatment options, including activated carbon and an upgrade to the activated sludge
process at the wastewater treatment plant (WWTP).
1997 Toxicity Identification Evaluation (TIE) tests indicated nonpolar organic
compounds to be the principal cause of effluent toxicity. However, follow-up TIE
Phase II tests were inconclusive. Due to the difficulty of identifying the effluent
toxicants, the city focused on tracking the sources of toxicity.
In February, a Refractory Toxicity Assessment (RTA) study was performed to
locate areas in the collection system where toxicity was originating. The results
showed that Softspun (a hosiery facility), the Sandy Creek pump station and
Martins Creek pump station were discharging refractory toxicity. The city met
with Softspun, inspected the facility and required information on all chemicals
used for dyeing and cooling water conditioning. Shortly after the meeting,
Softspun informed the city that they would be reducing production and
subsequently closing in 1998.
Treatability tests performed as part of the RTA study showed that hydrogen
peroxide (112O2) reduces toxicity at a dosage of 5 mg/L. However, toxicity is not
eliminated by this treatment. The city implemented H202 treatment within a few
months and began collecting samples before and after H202 addition to evaluate its
effect on toxicity.
The city developed pretreatment limits for toxicity for all of its permitted industrial
users. The revised permits included a THE requirement that would become
effective if the industry failed its quarterly toxicity testing. The city also inspected
each permitted industrial user and prepared chemical optimization plans that the
industries could use as a guide for minimizing the discharge of toxic materials.
1997 Progress Summary: TIE tests were not successful in identifying the
effluent toxicants; therefore, the city focused on tracking sources of toxicity.
An identified source of toxicity, Softspun, was eliminated. In addition, the
city established toxicity limits, performed in-depth inspections and prepared
chemical optimization plans for major industrial users. H202 treatment was
also added to the city's W WTP to reduce effluent toxicity.

1998 The city's WWTP effluent exhibited a trend of little or no toxicity in the beginning
of the year followed by increased toxicity in July and then no toxicity at the end of
the year. Five of nine toxicity tests showed compliance with the permit limit and
only one test showed toxicity at less than 78% effluent (as a chronic value, ChV).
As a result of the low toxicity, it was difficult to characterize the causes and
sources of toxicity. A TIE test performed in April was inconclusive because
toxicity was marginal (ChV = 87%). However, results were interpreted to indicate
the presence of nonpolar organic toxicants.
Effluent samples collected after hydrogen peroxide (H2O2) addition and final
aeration were four to five -fold less chronically toxic than those collected before
peroxide/aeration treatment. H2O2 treatment was started in 1997.
The city appointed a new Pretreatment Coordinator and initiated an expanded
pretreatment program with a focus on toxicity reduction. Progress includes (1)
issuing a new chemical usage form that industries will use to submit weekly
chemical usage data, (2) setting up a computer data base of chemical usage by
industry, (3) continued toxicity monitoring of industries, (4) quarterly inspections
of major industrial users, and (5) increased communication with industries (i.e., at
least monthly).
Burkart Carolina, a relatively small industrial user of the city's W WTP, began
using a phthalocyanine blue pigment in production in the fall of 1997. In March
and April, 1998, the city observed increased effluent toxicity as measured by
Microtox. Results of a discharge sample collected from Burkart in June showed
chronic toxicity to C. dubia. Follow-up tests showed toxicity to C. dubia when the
pigment was treated in a bench -scale simulation of the city's WWTP. Based on
the monitoring results, Burkart voluntarily ceased using the pigment. A follow-up
sample of Burkart's discharge was not chronically toxic at the facility's flow
contribution; therefore, the discharge was eliminated as a source of toxicity.
C. dubia tests showed no decrease, and even a slight increase, in toxicity after
activated sludge treatment at the city's WWTP. Increases in toxicity have been
observed at other POTWs as a result of the formation of toxic treatment
byproducts, especially when toxic surfactants are involved.
In December, Americal Corporation's effluent was toxic. As required in the
industrial user permit OUP), a follow-up RTA test was performed to determine if
the discharge was contributing refractory toxicity. However, the test was invalid
due to toxicity test problems. A follow-up test was planned for January 1999.
1998 Progress Summary: The relatively low effluent toxicity was difficult to
characterize. The city appointed a new Pretreatment Coordinator and
initiated an expanded pretreatment program with a focus on toxicity
reduction. An identified source of toxicity, Burkart Carolina, was controlled.
Samples collected within the WWTP show no decrease, or a slight increase, in
toxicity after activated sludge treatment. These results suggest the presence
of toxic breakdown products, perhaps originating from a surfactant.

1999 In January, the RTA test showed refractory toxicity in Americal's discharge. As
required under the ", Americal initiated a TRE. Americas retained a consultant
to (1) review data on chemical composition and use, (2) prepare a plan for
evaluating the cause(s) of toxicity, and (3) perform tests on waste streams and
selected production chemicals. Tests showed that none of the five most used
chemicals contribute to toxicity individually.
In February and March, Americal assessed the refractory toxicity of waste streams
and combinations of dye chemicals and evaluated post -treatment of the effluent
with H2O2. Results showed that Americal's pretreatment facility effluent is more
toxic than its influent. At the same time, a TIE test showed that effluent toxicity is
caused by nonpolar organic compounds. A polymer used for treatment was
suspected of introducing toxicity; therefore, Americal reduced polymer use by one
third. In addition, tests of the production chemicals indicated that toxicity is
associated with one or more of the scouring, leveling, or wetting agents.
In March, Americal notified the city of a new bleaching process. Tests showed
that a combined bleach/dye waste stream sample was more toxic than the dye
waste stream sample alone. Follow-up tests of the bleach stream samples were
inconclusive because of the toxic background levels of chlorine and H2O2.
Although the oxidants contribute to toxicity, chlorine and H2O2 were expected to
be reduced when Americal's discharge mixes with the city sewer flow because of
high oxidant demand of domestic sewage. Although results were inconclusive,
Americal substituted the wetting and softening agents used in the bleaching
process.
In May and June, additional tests were performed to evaluate the effect of reduced
polymer use on Americal's effluent toxicity. A discharge sample was collected on
May 14ie after polymer use was reduced by one-third. Test results showed much
less toxicity than in April. Americal further reduced polymer usage after the
vendor provided information showing that the polymer contains nonyl phenols. A
follow-up test performed by Americal in June was a "pass" and a test performed
by the city in the same week was nearly a "pass". A follow-up RTA test
performed in July showed no refractory toxicity in Americal's discharge. A
confirmatory RTA test is scheduled for September. If Americal passes the test, the
THE will be completed and their discharge will be considered to be nontoxic.
However, additional monitoring will be performed to confirm that Americal's
discharge is no longer a source of toxicity.
It is difficult to track sources of toxicity when toxicity is intermittent, complex,
and at low levels. Therefore, the city initiated the development of a new long-term
sampling device (Toxicity Tracking System®) that can continuously collect
nonionic, nonpolar organic toxicants. The TTS consists of a semipermeable
membrane system (SPMS) for sample collection and procedures for recovering
nonpolar organic toxicants, which are the principal toxicants in the city's W WTP
effluent.

In April, the SPMS was deployed in the Nuthush Creek WWTP influent and
effluent. Results showed that toxicity can be recovered with the TTS. Based on
the success of initial testing with the TTS, the city committed to implementing an
intensive TTS monitoring program. This program included deployment of SPMS
in upstream sewer lines and selected industrial discharges. In May and June, the
monitoring effort focused on the Sandy Creek sewershed, which has been shown
to be a principal, albeit intermittent, source of toxicity.
TTS results showed that the gravity line to the Sandy Creek pump station was the
most toxic sample. This result confirms previous short-term monitoring results
that have found this location to be toxic. An SPMS sample collected upstream of
the Sandy Creek pump station in an area receiving flow from the Harriett &
Henderson cotton mill (Scott Parker) was also toxic. Other samples collected in
the Sandy Creek sewershed, including Americal's discharge, were substantially
less toxic.
Follow-up tests were performed in July to confirm the TTS results. These tests
included RTA procedures and toxicity testing using a C18 solid phase extraction
(SPE) column. The results generally support the TTS data in showing that a sewer
line serving a Harriett & Henderson cotton mill (Pinecrest St) was contributing
toxicity. In addition, the RTA results showed refractory toxicity in a combined
sample of the Sagefield, Vance School and Cannel Ridge sewer lines. A review of
businesses located on the Vance School Line did not indicate potential sources of
toxicity. Burkart Carolina, the only industry located on the Sagefield line, is
currently being evaluated by the city.
Based on results showing toxicity in sewer lines serving the Harriett & Henderson
cotton mills, the city conducted inspections of the North and South mills in
August. The city observed high water marks and relatively high conductivities in
several manholes at the North cotton mill. These findings provided evidence for
cooling water or some other process waste being discharged to the city's sanitary
sewer. Harriett & Henderson is not permitted to discharge cooling water to the
sanitary sewer and the city is concerned about potential residual biocides in the
cooling water, which, in sufficient concentration, could cause toxicity at the city's
WWTP. The city has required Harriett & Henderson to provide information on
location and frequency of cooling water discharges to the sanitary sewer and the
type and dosage of chemicals used in the cooling water system.
Frequent toxicity monitoring of the discharges from the cotton mills is being
performed using Microtox. If the cotton mills are confirmed to be sources of
toxicity, Harriett & Henderson will be required to perform TREs and must achieve
compliance with a chronic toxicity limit.
The city again attempted to identify the effluent toxicant(s) in a toxic sample
collected June. Again, the results were inconclusive because toxicity could not be
recovered using EPA's TIE procedures.

In July, the city inspected Omega Cleaning Products, which is involved in the
preparation and distribution of cleaners. Drums used in preparing and distributing
Omega's industrial cleaning products are routinely taken to a local car wash on
Norlina St. for rinsing. Information provided by Omega showed that several
cleaners contained nonyl phenols and quaternary amine compounds that can cause
toxicity. The city is in the process of requiring Omega to evaluate alternative
disposal methods.
In June, the city completed the upgrade of the trickling filter process. The city's
consultant had recommended the upgrade to optimize the capability of the WWTP
to reduce toxicity. Since the upgrade, the city has observed increased BOD
removal in the trickling filters. Coincidentally, effluent toxicity generally
decreased in July through September compared to earlier in year.
In August, the city initiated treatability tests to determine (1) toxicity reduction by
activated carbon and (2) the degree of toxicity treatment that could be achieved by
the planned activated sludge process upgrade. The city is currently operating a
"fill and draw" bioreactor that simulates the aerobic stage of the planned biological
process. Once steady-state operation is achieved, the city will collected samples
for toxicity testing. Effluent samples from the WWTP will also be tested to
compare with the bioreactor simulation. Recent results of carbon isotherm testing
suggest that carbon will remove toxicity. The city is currently investigating the
feasibility of adding carbon treatment at the WWTP.
1999 Progress Summary: Toxicity at a major industrial user was eliminated.
The city's WWTP effluent was still toxic; therefore, the city developed a new
long-term sampling device to locate sources of intermittent, complex, and low
level toxicity. This device identified a sewer tine serving the Harriett &
Henderson South cotton mill as a source of toxicity. A follow-up inspection at
the North and South cotton mills indicated a potential for cooling water
discharges to the city's sanitary sewer. The city has requested information on
the cooling water discharges and the type and quantity of cooling water
additives. If the cotton mills are confirmed to be sources of toxicity, Harriett
& Henderson will be required to perform TREs and must achieve compliance
with a chronic toxicity limit. The city is evaluating toxicity treatment options
because of the time that may be required to confirm and eliminate sources of
toxicity.

D) TOXICITY REDUCTION EVALUATION (TRE) PLAN DURING ONE-
YEAR EXTENSION
This plan describes the tasks that are required to identify and control the nature and
source(s) of toxicity, and thereby achieve compliance with the discharge permit limit for
toxicity. The city plans to use the same procedures that were applied to identify and
control three previous sources of toxicity in its sewer system. However, if necessary, the
city is prepared to modify or develop procedures, as was achieved in earlier trackdown
studies. It is important to note that TREs are a step -wise process in which results of
initial tasks are used to refine the scope of subsequent efforts. Therefore, the scope of
work described herein may change based on the results of initial tasks.
The scope of work considers the following progress and issues:
1. The city understands that an extension of the THE is not a matter to be taken lightly.
Therefore, all work must be well focused to achieve specific outcomes. Any third
parties such as industrial users must meet a interim schedule that is consistent with
the city's final deadline.
2. The Sandy Creek sewershed has been shown to be a general source of toxicity. Of
the potential sources in this sewershed, Americal Corporation may have eliminated its
toxicity; however, Harriett & Henderson's two cotton mills are only starting their
investigation. Also, Burkart Carolina continues to be monitored as a potential
toxicity source. In the past, it has been difficult to pinpoint the actual source of
toxicity in the Sandy Creek sewershed because of the intermittent characteristic of
toxicity. The city proposes to overcome this problem by frequently sampling the
discharges of the Harriett & Henderson's cotton mills. In addition, additional RTA
testing will be performed on Americal and Burkart discharge samples. Once toxicity
sources are identified, the city will impose THE requirements.
Recent results also show potential toxicity in the city's other main sewershed, the
Redbud area. Sources of toxicity in this sewershed must also be investigated to
ensure compliance. The city plans to perform RTA analyses of samples collected on
the Redbud main line. If toxicity is apparent, a toxicity trackdown study will be
performed and toxicity sources will be identified and required to eliminate toxicity.
4. The city is in the process of designing a new treatment system for an expanded
Nuthush Creek WWTP. The definitive effect of the new system(s) on toxicity is
unknown. In 1990, the city of Durham was upgrading its treatment plants and chose
to evaluate the effect of the new facilities on toxicity. The city of Durham conducted
a bench -scale simulation of the new treatment system, which indicated that the
upgrade would eliminate chronic effluent toxicity. Based on these results, DENR
waived the THE requirement and after completion of the upgrade toxicity monitoring
demonstrated compliance with the toxicity limit. A similar, yet streamlined, study is
underway at the city of Henderson. If the city's study shows that compliance can be
achieved with the upgraded W WTP, a THE waiver will be requested.

5. Effluent toxicity has consistently been caused by nonpolar organic toxicants.
Nonpolar organic toxicants generally have a high affinity to activated carbon. If
toxicity can be removed by activated carbon, the city will investigate the feasibility of
activated carbon treatment at the WWTP.
6. EPA's Toxicity Identification Evaluation (TIE) procedures have not been successful
in identifying the effluent toxicants. However, the toxicants may be resolved by
testing the effluent sample at a much higher concentration. Information about the
characteristics of the toxicants would be helpful in identifying the source(s) of
toxicity.
The city will be proactive in working with DENR in addressing the toxicity issue.
The city will maintain contact with DWQ to discuss progress and solicit
recommendations on addressing toxicity issues.
Task I - Trackdown of Toaac Industrial Dischargers
The city will continue to monitor sections of the sewer system for toxicity using
N icrotox, particularly the Harriett & Henderson cotton mills, Americal and Burkart
Carolina in the Sandy Creek sewershed, and the Redbud main line. Due to the
intermittent nature of toxicity, the city must perform frequent monitoring using N icrotox
until toxic samples are obtained. Toxic samples will be sent to the laboratory and tested
for chronic toxicity to Ceriodaphnia dubia, the test species specified in the city's permit.
Alternatively, the Toxicity Tracking System (1TS) will be used to ensure that
intermittent low-level sources of toxicity are identified.
Trackdown studies will be performed to pinpoint toxicity sources. If an industrial user(s)
is shown to be a consistent source of toxicity, the city will perform a Refractory Toxicity
Assessment (RTA) test to determine if the toxicity is refractory and would be expected to
pass through the WWTP. If refractory toxicity is found, the industry will be required to
perform a TRE.
Task 2 — Update Chemical Ophnazation Plans for Industrial Users
In 1997, the city prepared chemical optimization plans (COPs) for each permitted
industrial user. The COPS provided guidance on how industries can identify and
optimize, substitute or reduce potentially toxic chemicals. The COPS were developed
using information gathered in in-depth inspections of the facilities and data on process
and treatment chemicals (e.g., PT101 forms, material safety data sheets). The completed
COPS required the industries to submit weekly usage data on the chemicals and
information on chemical optimization practices.

The city proposes to require the industrial users to update their COPS with additional
information on chemicals containing surfactants and biocides, which are the toxicants of
concern. The city plans to request permitted industrial users to obtain the following
information:
1. Product stewardship data and supporting data from vendors on chemicals used for
• Cleaning equipment or products (e.g., textiles, fabricated metal) in the
manufacturing process;
• Preparing materials for processing by adding softening, wetting, scouring or
leveling agents or fixatives;
• Dispersing or promoting the solubility of other chemicals used in the manufacturing
process; and
• Pretreatment of wastewater using additives that contain surface-active agents.
2. Product stewardship data and supporting data from vendors on process chemicals that
contain sulfonated compounds, quaternary amines and phenolic compounds,
particularly nonyl phenols.
The city may add additional types of chemicals to this list as needed. The city plans to
require the industrial users to submit this information in updated COPS together with an
assessment of the need to substitute or optimize the use of chemicals of concern.
The city will continue to evaluate non -permitted industrial users that are suspected of
using toxic materials. Where necessary, the city will require these users to provide
information on the noted chemicals as well as for biocides used for cooling water
purposes.
Task 3 —Biological Treatability Testing
The city is in the process of considering plans for an upgraded WWTP, which will
include a new biological treatment system. The general design of the biological
treatment process will be a multi -stage process that includes both organic carbon removal
and at least some biological nutrient removal. This process will be evaluated with respect
to its toxicity reduction capability.
The process will be tested in a simple bench -scale, "fill and draw" study. Although the
new process will consist of several stages, the stage that is likely to achieve the greatest
toxicity reduction is the aerobic stage. The current design allows for a hydraulic
retention time of 16 hours in aerobic treatment, which may oxidize the toxicants.

The testing will involve treating the WWTP influent with the current activated sludge for
a sufficient period of time to establish a biomass that is similar to the activated sludge of
the new aerobic stage. The test will be started by adding WWTP influent to an aerobic
reactor with the biomass. After 16 hours, the air will be stopped, the biomass solids will
be settled and the effluent will be withdrawn and discarded. Excess biomass solids will
be wasted as necessary, a new WWTP influent sample will be added and the reactor will
again be aerated. It will be necessary to perform the fill and draw treatment for several
weeks (at least one sludge age) to ensure that the biomass is acclimated to the process.
Once the process has stabilized, the city will collect effluent samples for toxicity testing.
If results demonstrate that the new treatment process is expected to achieve compliance
with the toxicity limit, the city will request a waiver of the TRE.
Task 4 — Evaluate Activated Carbon Treatment
Several municipalities have evaluated the use of activated carbon, both in powdered and
granular form, as a toxicity reduction technique. Several primary questions must be
answered before activated carbon can be considered at the city's WWTP:
• Will the toxicant(s) be removed at reasonable carbon doses and practical contact
times?
• Can the WWTP be practically retrofitted to add carbon treatment?
• Can the existing sludge train handle the carbon with no negative impact on
equipment or sludge stabilization? Will activated carbon adversely affect sludge
disposal?
Preliminary results indicate that carbon can remove toxicity. However, additional testing
is required to determine the appropriate carbon dose. The carbon dose will be determined
by performing a carbon isotherm on aliquots of an effluent sample using a pulverized
(powdered) activated carbon. Following carbon treatment, the samples will be double
filtered through glass fiber filters to remove carbon fines. Recent tests show that
filtration does not remove effluent toxicity; therefore, toxicity reduction should be related
to carbon treatment.
The treated samples will be submitted for chronic toxicity testing using C. dubia. Total
organic carbon (TOC) is a useful parameter for evaluating the efficiency of carbon
adsorption and is the parameter of choice for process control of carbon treatment
processes. Therefore, TOC analyses will also be performed on the test effluents.
An isotherm plot will be drawn using the chronic toxicity endpoints (IC25, ChV) and
carbon doses. If toxicity is successfully removed, this plot will indicate the carbon dose
needed to achieve compliance. The carbon dose data will be used in assessing the
feasibility of carbon treatment at the city's WWTP.

Currently, the most cost effective and technically feasible approach may be to add
powdered activated carbon to the activated sludge treatment process. An assessment will
be performed to evaluate this option and other approaches for adding carbon treatment to
the WWTP. The assessment may include a review of the WWTP's design plans and
specifications and operations and performance data. Based on this review, the city will
prepare a letter report specifying the available options, the preferred option(s), and
recommendations for tasks to select and design a carbon treatment process. If necessary,
this report will include rough estimates of the capital and operating costs of the treatment
options.
Task S — Toxicity Identification Evaluation
A high performance liquid chromatography (HPLC) analysis performed on a toxic June
effluent sample showed that the nonpolar organic toxicants are not readily recovered.
Although toxicity was recovered from the initial C18 solid phase extraction (complete
mortality in 24-hours in the methanol eluate corresponding to 400% effluent), toxicity
was not recovered from the HPLC column. No chronic effect was observed in any of the
30 methanol fractions eluted from the HPLC column and tested at 165% effluent. These
results suggest that the toxicant(s) was spread out among the fractions and therefore, not
readily detected. Surfactants have this characteristic; however, additional testing is
needed to confirm this conclusion.
It is possible to test the HPLC fractions at a higher concentration, which may reveal the
toxicants. The city proposes to pass a very large volume of effluent sample through the
C18 column to concentrate the toxicants as much as possible. The eluate from this
column will then be fractionated on the HPLC column and the resulting 30 fractions will
be tested for toxicity to C. dubia. Information about the characteristics of the toxicants
will be very helpful in identifying the source(s) of toxicity. The results may indicate
whether the toxicant is a surfactant, biocide or pesticide that is likely to be discharged by
a particular industry.
Task 6 — Regulatory Interaction
The city will maintain contact with DWQ to discuss progress and solicit
recommendations on addressing toxicity issues. Again, quarterly progress meetings (at
the Regional Office unless otherwise desired by the Division) are suggested.

E) CITY STANDARD CHRONIC TOXICITY MONITORING AND SPECIAL CONDITIONS
FOR INDUSTRIAL DISCHARGERS
In managing its Pretreatment Program, and particularly with respect to chronic toxicity monitoring
requirements, the City requires the following language in all permits issued to industrial dischargers:
"Effluent from Pipe _ shall be monitored quarterly by the City using a modified ceriodaphnia chronic
toxicity method (DEHNR 1991) and the Microtox Chronic Toxicity test (Microbics 1994). These tests will
include at least one sample concentration that is equal to the maximum percent flow contribution of the
discharge to the Nutbush Creek W WTP as defined by the City when the test is performed.
If the Ceriodaphnia test result shows chronic toxicity (failure) at the maximum percent flow contribution,
unless otherwise notified by the City will perform a follow up toxicity test within the
next calendar month using a modification of EPA's refractory toxicity assessment (RTA) procedure (1997).
This test will involve treatment of the discharge sample in a bench -scale simulation of the Nutbush Creek
W WTP and subsequent toxicity measurement. The RTA test will estimate the "refractory" toxicity of the
discharge, which is the toxicity that would be expected to pass through the Nutbush Creek WWTP and
contribute to effluent toxicity. All test results shall be sent to the WWTP Director no later than 10 days
after receiving the results.
Unacceptable RTA toxicity is defined as a significant difference between the chronic inhibition
concentration (IC 25) values for the discharge - spiked test simulation and the control simulation as
determined by a comparison of the 95 percent confidence limits. If the RTA results show unacceptable
toxicity, the following limitations and requirements shall become effective:
(1) A toxicity reduction evaluation (TRE) to identify the causes and sources of chronic refractory
toxicity shall be performed by the industry. The THE shall begin within 30 days of receiving the
RTA results showing unacceptable toxicity and a report on the THE shall be submitted to the
WWTP Director within six months of initiating the TRE. The THE Report shall identify
measures to reduce toxicity and shall include a schedule for implementation of the control
measures. In addition, monthly progress reports shall be sent no later than 15 days past the last
date of the previous month.
(2) After implementation of the selected toxicity reduction method, toxicity monitoring using the
RTA procedure shall continue on a monthly basis by the industry until results of two consecutive
monthly tests show no unacceptable chronic refractory toaicity(as defined above). Once this
condition is met, the frequency of monitoring with the RTA procedure will be reduced to quarterly
testing. After a year of quarterly monitoring or RTA tests that show no chronic toxicity at the
percentage flow contribution, semi-annual monitoring will be performed.
The City reserves the right to increase or decrease this monitoring requirement"

F) CURRENT PLANS AND COST DATA — PROPOSED MASTER PLAN IMPROVEMENTS TO NUTBUSH CREEK
WASTEWATER TREATMENT PLANT — FROM MCKIM & CREED STUDY AND ANALYSIS
Figure V-1
Proposed Prioritization Flow Chart
Nutbush Creek Interceptor
Phase I - III Reduction Program
Red Bud Pump Station Upgrade
$3,000.000
Nutbush Creek WWTP Expansion
$23,500,000
1/1 Reduction Program
$0 - $4,625,000
Red Bud Interceptor N. Vance
Sandy Creek Pump Station
System Wide'
$880,000 Interceptor
and Force Main
SCADA System
$1,150,000
Zeb Robinson Pump
Denver - Partin
Station and Force Main
Martin Creek Pump Station
$25,000
$280,000
and Force Main
$590.000
Generator Transfers
$190,000
Red Bud Force Main
$940,000
Martin Creek Interceptor
All project Costs Include contingency,
Industrial Park Pump Station
included in
administration, legal and technical services
and Force Main
Nutbush Creek WWTP
$580,000

Projects
All project in capital plan
Nutbush WWTP Expansion
Nutbush WWTP Expansion
Red Bud/Nutbush Interceptor
(HUCG Project)
Blended Financing
Nutbush WWTP Expansion
HUCG Project
• $3.OM HUCG Approved
• $15M EPA-SRF Loan
• $8.5M Market Rate Loan
Table V-1: Financial Scenarios
Capital Cost
$35,800,000
$23, 500, 000
$26,500,000
$3,000,000 -
$15,000,000
$8, 500,000
$26, 500,000
Rate
Annual P&I
2.6%
$2.318.000
5.0%
$2,873,000
2.6%
$1,522,000
5.0%
$1,886,000
2.6%
$1,716,000
5.0%
$2,126,000
2.6% $971,000
5.0% $682,000
$1,653,000
$/nno.
$11,000 gal
5,000 gal. usage
$2.12
$10.58
$2.62
$13.12
$1.72
$6.94
$1.39
$8.61
$1.57
$7.85
$1.94
$9.71
$0.89
0.62
$1.51
$7.55

7'
J"" EL FIUNTJR
NOR CAROLINA DEPARTMENT OF
ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
August 27, 1999
242
Mr. Reginald C. Hicks
Henderson Nutbush WWTP
P.O. Box 1434
180 Beckford Drive
Henderson, NC 27536
SUBJECT: Date for laboratory inspection.
Dear Mr. Hicks.
I am confirming the date for inspection of your
laboratory and review of your North Carolina data on
September 23, 1999 at 9:30 A.M. Please provide raw data
and copies of your DMRs for the months of May, June,
July and August, 1999.
Please provide the following:
1. Make available for review North Carolina data for a
period of one year for all parameters for which you
are certified during the inspection.
2. You must copy the previous three months (before the
inspection date) of worksheets and must send them to
this office for review. Due 2 weeks before
inspection.
3. Provide information that all chlorinated samples are
dechlorinated and other preservation requirements are
met per the Federal Register.
4.Supply a room for review of data by inspector(s).
5.Supply any data/reports sent by/to a North Carolina -
certified lab(s) for analysis of North Carolina
samples. (Commercial Lab or Subcontracted Work)
Call me at [phone], extension 249, if you
have any questions or must arrange a new inspection
date.
eMail: [e-mail]
Sincerely,) —
n � t .
✓,��1
V. Rayl Boling, J)r
Laboratory Section
CC: James W. Meyer
Marilyn Deaver
Raleigh Regional Office
U1lO RATO qY SECTION
4405 REEDY CREEK ROAD, RALEIGH, NORTH CAROLINA 27907-6445
PHONE [phone] FAX [phone]
AN EQUAL OPPORTUNITY / AFFIRMATIVE ACTION EMPLOYER - 50% RECYCL E0/10% POET -CONSUMER PAPER

_Ay of Henderson Office of
P. O. Box 1434 City Manager
180 Beckford Drive Eric M. Williams
Henderson, NC 27536
[e-mail]
Phone:[phone] Fax:[phone]
March 10, 2000
Mr. Kenneth Schuster, P.E.
Regional Supervisor
NC DENR
Division Of Water Quality
1628 Mail Service Center
Raleigh, NC 27699-1628
RE: Response to February 28th letter
November, 1999 Quarterly THE Report
Special Order of Consent
City of Henderson
NPDES Permit NCO020559
Vance County
Dear Mr. Shuster,
= 0 C
Q
try
The City of Henderson received your letter dated February 28, 2000 in
regard to questions that the Division Of Water Quality has pertaining to our
November 1999 quarterly THE Report. Since receiving your letter, the City Staff
has been assembling information and data in responding to your questions and
we hope we have addressed each issue effectively and to your satisfaction.
Attached you will find a letter from Tom Spain our Wastewater Treatment
Plant Director who has outlined in detail a response to each question dated in
your February 28th letter. I think you will find that Mr. Spain has documented
each concern that was addressed and that his answers will provide you the
necessary assurances that our Wastewater Treatment operations are both
efficient and environmentally sound. As always, we are most appreciative of the
support and guidance of you and your staff as we all work toward the
management and operation of our wastewater system in a environmentally
sound, prudent and physically responsible manner.
After you have had the opportunity to review our responses, if you or your
staff should need any further information or if a meeting is necessary to further
discuss our responses, please do not hesitate in contacting us.
Thank you for you time and attention in this matter. If further information
is needed during the course of your reviews, please contact us.
\WDMUPGLOVER$\Letters from C\Kenneth Schuster SOC Ittr March 10. 2000doc.doc Page 1 of 2

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With best regards, I am
Sincerely,
CITY OF HENDERSON
Wil iams
City Manager
EMW/pg
Attachment
C: Kirk Stafford-RRO
Shannon Langly-NPDES Compliance
Mark R. Warren, Assistant City Manager
Tom Spain, WWTP Director
Linda Leyen, Chief Operator
Reggie Hicks, Lab Supervisor
John Botts, Aquatic Sciences Consulting
Glenn Dunn, Poyner and Spruill
Tim Baldwin, McKim and Creed
\WAMIN\PGLOVER$\Letters from C\Kenneth Schuster SOC Ittr March 10. 2000doc.doc Page 2 of 2

CITY OF HENDERSON
Post Office Box 1434 Nutbush Creek Wastewate
180 Beckford Drive Treatment Plant
Henderson, North Carolina 27536-1434
Phone: [phone] FAX: [phone]
March 8, 2000
Mr. Kenneth Schuster, P. E.
Raleigh Regional Supervisor
NC DEHNR DWQ
1628 Mail Service Center
Raleigh, NC 27699-1628
Subject: Response to February 28d' letter
November, 1999 Quarterly THE Report
Special Order of Consent
City of Henderson
NPDES Permit NCO020559
Vance County
Dear Mr. Shuster,
I am writing in response to your February 28d' letter to Henderson City Manager, Eric
Williams, since the management of the THE Program and Redbud Pump Station
operation is my direct responsibility.
I anticipate that Mr. Williams will include a cover letter to this response because of his
desire to maintain a direct positive working relationship with the State and the vital
importance to the City to resolve any wastewater issues promptly to the State's
satisfaction.
Response to Questions and Comments in the Division of Water Quality's Letter
(Dated February 28, 2000)
1. Harriet & Henderson south cotton mill was identified as a new source of toxicity.
The facility is authorized to discharge domestic waste only but evidence of
nondomestic discharges was obtained. What evidence did the City obtain? Did the

City investigate for cross connections during subsequent visits? Why has the City not
investigated this facility before now considering its size and potential for toxic
discharges? Did the city issue a Notice of Violation (NOV) or assess civil penalties?
Response: The evidence of nondomestic discharge from the Harriett & Henderson
south mill was an indication of refractory toxicity in the discharge. A sample of the
Harriett & Henderson south mill discharge collected in September 1999 failed the
refractory toxicity assessment (RTA) test as described in the November 1999
quarterly progress report (please see last paragraph on page 4 of the report).
In September, the city directed Harriet & Henderson to investigate possible cooling
water losses at the south mill (city letter dated September 20, 1999). The city was
concerned that cooling water piping was leaking and biocides or other cooling water
chemicals were possibly being discharged to the City's sanitary sewer. Harriet &
Henderson performed the investigation; however, the results of dye tests reportedly
did not show evidence of cross connections (Harriet & Henderson letter dated
October 14, 1999).
In addition to all other major industries, the city has been investigating the Harriet &
Henderson north and south cotton mills since 1997. In 1998, MicrotoxTm tests
performed on samples collected from the sewershed and the two cotton mills
indicated toxicity. However, a follow-up RTA test performed in August 1998 did not
indicate a potential to contribute refractory toxicity to the Nutbush Creek W WTP.
Also, tests performed in March 1999 with Ceriodaphnia dubia did not show toxicity
at concentrations corresponding to the mills' flow contribution to the W WTP.
The monitoring results suggested a potential for toxicity in the Mills' discharges,
which appeared to be intermittent. Toxicity tracking procedures available at the time
were not helpful in identifying intermittent toxic sources; therefore, the city
committed significant resources to developing a new monitoring tool, which is
designed to capture intermittent toxicity by continuously collecting samples over a
14-day period. In late May 1999, this tool, referred to as a semipermeable membrane
system (SPMS), was deployed in a sewer receiving the south mill discharge. A
toxicity test performed on the SPMS sample showed a relatively high level of chronic
toxicity to C. dubia. These results indicated the potential for the south mill to
contribute toxicity to the Nutbush Creek WWTP. It was necessary to test the
discharge by the RTA method to determine if the toxicity would be refractory (i.e.,
contribute to effluent toxicity at the city's W WTP). A follow-up RTA test of the
sewer serving the south mill discharge did not show toxicity (July 1999).
The city finally obtained evidence of refractory toxicity in the south mill discharge in
September 1999. The city met with Harriet & Henderson in November 1999 and
presented the evidence of refractory toxicity. However, Harriet & Henderson
expressed concern that the RTA results were inaccurate because their investigation
showed no cooling water discharges to the sanitary sewer and, even if cooling water
was being discharged, the cooling water chemicals were not being used at levels that

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would cause toxicity. Since permitted industries require two failures (raw sample test
followed by a RTA test) before a THE must be conducted the City agreed to retest the
south mars discharge. Harriet & Henderson sealed the two wash down pits at South
Henderson Cotton Mill to eliminate the possibility of a potential toxicant being wash
down to the sanitary sewer. A RTA test performed in December 1999 confirmed
refractory toxicity in the mill discharge (see February 2000 quarterly report);
therefore, the city issued a letter requiring Harriet & Henderson to perform a THE
(city letter dated February 10, 2000).
The City will issue a NOV to Harriet & Henderson for a toxic discharge.
2. Omega Cleaning Products was identified as cleaning product containers in a local
carwash when an onsite septic tank for treating wastewater was to be utilized. Did
the city issue a NOV or assess civil penalties and if not what was the reason?
Response: When Omega Cleaning Products was identified as a potential source of
toxicity, the city inspected the facility. During the inspection, it was discovered that
Omega was on a septic tank system and did not discharge to the city's sanitary sewer.
Nonetheless, a chemical inventory list was requested and received for review. Later,
when Omega called with questions about possibly relocating to a facility that
discharges to the sanitary sewer, the City determined that chemical containers were
being washed at a local car wash that discharges to the sanitary sewer. Omega was
notified to immediately cease the container rinsing and they complied (city letter
dated September 23, 1999).
The November 1999 quarterly report may have given the impression that Omega was
washing all of their product containers at the carwash. However, the city was told
that only those containers purchased and used at the car wash were rinsed (after the
contents were emptied). The city does not believe that a NOV or civil penalty is
necessary in this case because (1) the cleaning products were being used at the car
wash and are specified for use in car washes by the manufacturers, (2) an initial
review of the data, using a toxicity modeling program (Aquatox), did not indicate a
potential to cause toxicity at the city's W WTP, and (3) Omega complied immediately
with the city's order.
The city is continuing to investigate Omega's products and all car washes by
reviewing chemical inventories at each car wash. On March 1, 2000, the city
submitted a letter to each of the car washes requesting a list of chemicals used and
their material safety data sheets (MSDS) and product stewardship data. If the
chemicals pose a potential toxicity risk, the city will request additional information
and testing.
3. In August 1999, Americal Corporation replaced VircoSoft 348 with SparLube LB50.
Did the city require Americal to test the new product prior to use?

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Response: During Americal's TRE, VircoSoft 348 was found to contain nonyl
phenols, which are potentially toxic. In August 1999, Americal substituted VircoSoft
348 with another softener (SparLube 50), which reportedly does not contain nonyl
phenols. The city decided to evaluate the effect of the substitution in a RTA test
performed in September 1999. In this test, Americal's discharge was not found to
contain refractory toxicity. A follow-up RTA test performed in December 1999
confirmed that Americal's discharge was not toxic. The city interpreted these results
as evidence that the substituted softener was not contributing to the WWTP effluent
toxicity.
Although Americal's discharge has not been toxic since the TRE, the city plans to
issue a letter to Americal requesting product stewardship data on SparLube LB50.
4. Mr. Tom Spain informed Ms. Judy Garrett, of the Raleigh Regional Office (RRO),
that a portable pump had been installed at the Redbud Pump Station and that the
pump combination will now be able to handle all received flow. Mr. Spain also
stated that the constriction in the downstream sewer line had been repaired three years
ago and that there have been no overflow problems since. What was the reasoning
for not installing this pump sooner since it would have eliminated a number of
overflows at this pump station? In addition, Mr. Spain has stated that any additional
pump capacity at the station would result in overflows downstream. Mr. Garnett also
informed Mr. Spain to pump and haul if necessary in the future to prevent overflows.
Please comment on why the City has not done this in the past to prevent overflows.
Response: I had been working on February 8, 2000 with the representatives of
Reynolds Construction Company, Godwin Pumps of American, Inc. and the WWTP
staff for over 16 consecutive hours with very little sleep before contacting Judy
Garrett of the Raleigh Regional Office on February 9, 2000 to notify her that the
portable bypass pump was in place and the Redbud bypass was stopped at 8:30 PM
on February 8, 2000.
My response to a question about potential overflows at Radio Lane was that we no
longer had any overflows at Radio Lane because a section of pipe downstream from
Radio Lane had been upgraded to larger pipe 3 or 4 years ago.
My memory was inaccurate because the pipe restriction was actually upgraded when
the City was required by the State to convert Redbud from a single pump to a lead/lag
two -pump operation in the early 1990's because the line could not handle a dual
pump flow without this upgrade.
This did stop the bypasses at Radio Lane but did not solve the hydraulic overload of
the interceptor to the WWTP in the Ross Mill Road area where the Sandy Creek and
North Henderson gravity lines combine with the Redbud gravity line.
Line surcharges from rainfall are now a problem in the Ross Mill Road area and the
Sandy Creek and North Henderson gravity lines.

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McKim and Creed Engineers have clearly identified the areas of the gravity
interceptors from Interstate 85 to the Nutbush Creek WWTP that need upgrade to
accommodate the wastewater flow.
This is part of a project to permanently upgrade the Redbud Pump Station and main
gravity interceptor to the W WCP. Plans for this upgrade have been under review by
the State since July, 1999.
The portable pump was not installed sooner because hydraulic upgrade of the gravity
interceptor to the Nutbush Creek WWfP should have been completed first since
some overflows are likely to be shifted from the more rural Redbud Pump Station
area to the more densely populated Ross Mill Road area during heavy rainfall with
Redbud Pumping at a higher discharge rate.
When the portable pump was put on line on February 81h, the Redbud Station had
almost stopped bypassing and the line in the Ross Mill area was not in a surcharge
condition.
I was concerned of the possibility that the pump would still cause a bypass and had
the staff stationed in the Ross Mill Road area to be sure the line did not overflow
during start up.
We have not had sufficient rainfall since February 8th for the portable pump to create
a bypass but some bypass problems are likely to occur during heavy rainfall, which is
supported by the engineering study.
The City did not pump and haul from the Redbud Station in the past because it did
not appear to be a viable alternative and the State had never requested that the City
take this action until my conversation with Ms. Judy Garrett on February 9`h, 2000.
All of the bypasses during the hurricane weather were beyond our capacity to haul
and access to the station with a tanker truck would have been infeasible during this
time.
Access to the station was impossible during the bypasses from snow just prior to the
portable pump being installed.
The City will make every effort in the future to pump and haul any wastewater that is
bypassing but there will be times when it is infeasible.
If any questionable pump and haul situations arise in the future, the City will contact
the State for a determination of the course of action to follow.

The City has met every deadline established in our Special Order of Consent (SOC)
with the State for upgrade of the Redbud Pump Station and Nutbush Creek gravity
interceptor.
The SOC requires all bypasses at Redbud to be eliminated by March 1, 2002.
The City plans to meet this schedule with a 20-year design that will be much more
than a temporary upgrade.
I trust this letter has sufficiently answered your questions.
The City of Henderson is striving to be proactive in meeting environmental concerns
that have been heightened considerably by new legislation, the State and increased
press coverage, but it is a reality that much of our infrastructure is aging and
repairs/replacement will be costly and require a reasonable time frame to accomplish.
If you have additional questions, please contact me at 252-431-6081
Sincerely,
-hamrw M. spc. C-P4
Thomas M. Spain,
WWTP Director
C: Eric Williams, City Manager
Mark Warren, Assistant City Manager
Linda Leyen, Chief Operator
Reggie Hicks, Lab Supervisor
John Botts, Aquatic Sciences Consulting
Glenn Dunn, Poyner and Spruill
Tim Baldwin, Mckim and Creed

NORTH CAROLINA DEPARTMENT OF
�L XA ENVIRONMENT AND NATURAL RESOURCES
A ...iii
NCDENRDIVISION OF WATER QUALITY
RALEIGH REGIONAL OFFICE
DIVISION OF WATER QUALITY
February 28, 2000
JAMES B. HUNT JR.
GOVERNOR CERTIFIED MAIL
RETURN RECEIPT REQUESTED
BILL HOLMAN Mr. Eric Williams, City Manager
SECRETARY City of Henderson
P.O. Box 1434
Henderson, NC 27536
KERR T STEVENS
DIRECTOR Subject:
November 1999 Quarterly THE Report
Special Order by Consent
EMC WQ96-005
City of Henderson
NPDES Permit NCO020559
Vance County
Dear Mr. Williams:
The Division received the subject report on November 10, 1999. Please send a
written response to the following questions and comments within 10 working days of
receipt of this correspondence.
1) Harriet and Henderson South Cotton Mill was identified as a new source of toxicity.
The facility is authorized to discharge domestic waste only but evidence of nondomestic
discharges was obtained. What evidence did the City obtain? Did the City investigate for
cross connections during subsequent visits? Why has the City not investigated this
facility before now considering its size and potential for toxic discharges? Did the City
issue a Notice of Violation (NOV) or assess civil penalties and if not why?
2) Omega Cleaning Products was identified as cleaning product containers in a local
carwash when an onsite septic tank system for treating wastewater was to be utilized.
Did the City issue an NOV or assess civil penalties and if not what was the reason?
3) In August 1999 Americal Corporation replaced VircoSoft 348 with SparLube LB50.
Did the City require Americal to test the new product prior to use?
4) Mr. Tom Spain informed Ms. Judy Garret, of the Raleigh Regional Office (RRO), that
a portable pump had been installed at the Redbud Pump Station and that the pump
combination will now be able to handle all received flow. Mr. Spain also stated that the
constriction in the downstream sewer line had been repaired three years ago and that
there have been no overflow problems since. What was the reason for not installing, .
this pump sooner since it would have eliminated a number of overflows at this
station? In addition, Mr. Spain has stated that any additional pump capacity at t
1628 MAIL SERVICE CENTER, RALEIGH, NORTH CAROLINA 27699-162S
PHONE [phone] FA% 919-571-4718
AN EQUAL OPPORTUNITY AFFIRMATIVE ACTION EMPLOYER - 50% RECVCLEO/10% POST -CONSUMER PAPER

Henderson
Page Two
station would result in overflows downstream. Ms. Garrett also informed Mr. Spain to pump and
haul if necessary in the future to prevent overflows. Please comment on why the City has not
done this in the past to prevent overflows.
If you have any questions or comments please feel free to contact me at 919-571-4700.
Sincerely,
Kenneth Schuster, P.E. ✓ f
Regional Supervisor
cc: Kirk Stafford-RRO
Shannon Langly-NPDES Compliance

DIVISION OF WATER QUALITY
November 29, 1999
MEMORANDUM
To: Ken Schuster
Through: Matt Matthews `y
From: Kevin Bowden 1)9
Va
Subject: THE Progress Report — November 1999
City of Henderson
SOC EMC WQ No. 96-05
NPDES Permit No. NCO020559
Vance County
This office has received and reviewed the facility's quarterly November 1999 THE progress
report. The report was transmitted to the Raleigh Regional Office by cover letter from the City dated
November 9, 1999. Item 2(b)(2) of the SOC specifies that quarterly THE progress reports be submitted
to DWQ no later than the 15th day of each February, May, August, and November. The SOC specifies a
September 30, 1999 date to achieve compliance with all final effluent limitations and contains an upfront
penalty of $5140.00 for failing to achieve compliance with final permit limitations while operating under
the previous Judicial Order by Consent. The report has been prepared with assistance from Aquatic
Sciences Consulting. The NPDES Permit requires compliance with a 90% chronic toxicity permit
limitation.
The report addresses THE activities accomplished from August 16, 1999 through November 15,
1999 and provides activities for the upcoming quarter.
Three (3) effluent multiple concentration Ceriodaphnia dubia chronic toxicity tests (August 18,
September 8 and October 27) were conducted during the study period. Chronic values measured 21.2%,
77.9%, and 21.2%, respectively.
The City initiated TIE testing on a June effluent sample. The results of this testing were reported
as inconclusive. Although toxicity was recovered from C18 solid phase extraction testing, toxicity was
not recovered in accompanying methanol eluate fractions. Testing results suggest that toxicity is spread
out among the eluate fractions and not easily detected, a characteristic of surfactants. Additional testing
is necessary to confirm or deny this assumption.
Pretreatment program initiatives include:
➢ Identification of a new source of toxicity, Harriet & Henderson South Cotton
Mill
➢ Review of Americal's THE efforts
➢ Review of weekly chemical usage reports
➢ Continued toxicity monitoring of Ns
➢ Continued quarterly inspections of major Ns
➢ Review of small Ns with water usage as low as
➢ Communication with IUs regarding pretreatmen
OMEGA CLEANING PRODUCTS
15,000 cubic feet per month
activities
Omega Cleaning Products, a local industry was targeted as potentially contributing to refractory
toxicity. The Company was taking spent drums containing cleaning solutions to a local car wash for
rinsing. Based on information provided by the Company and the potential from washdown to contribute

surfactants to the POTA City notified Omega that cleaning of pr t containers at a local car wash
was unacceptable.
HARRIET AND HENDERSON COTTON MILLS
Refractory Toxicity Assessment (RTA) and Toxicity Tracking Systems (TTS) results from May
and June suggested that sewer lines serving Harriet & Henderson (H&H) North and South Mills
contributed intermittent toxicity to the POTW. The City inspected the Company on August 16 and 17
and obtained "further evidence of nondomestic discharges." Harriet & Henderson Mills are permitted to
discharge only sanitary wastes to the City's system The City issued a letter to H&H in September
describing evidence for the toxic discharges and providing a list of actions for investigating the
discharges. In late September RTA testing on discharge samples from both mills was performed. Results
indicated that the south mill discharge was a contributing source of refractory toxicity versus the control
effluent (IC25 of 19.7% and 36.9%), respectively.
On October 14, H&H submitted a reply to the City regarding their THE progress and indicated
that no cross connections had been found between the cooling tower discharge piping and the sanitary
sewer. The report notes that the City plans to meet with H&H representatives to discuss RTA test results
and THE progress.
AMERICAL CORPORATION
RTA testing of Americal's effluent during July suggested that the effluent was not contributing
refractory toxicity (IC25 of 69.6%). During August the Company replaced a softener, VircoSoft 348,
with another softening agent, SparLube LB 50 which reportedly does not contain nonylphenols.
An August RTA procedure using Americal's wastestream was invalidated due to an
"interference" which was observed in the RTA sample treatments and not the RTA control. TriTest
Labs, the laboratory performing the RTA testing, observed a biological growth resembling fungi in the
RTA samples. This growth was not observed in the controls for RTA testing or for other clients during
the test period.
Results from the September RTA indicated overlapping 95% confidence intervals (C.I.) in the
Americal sample (IC25 C.I. of 6.7-32.3) and control sample (IC25 C.I. of 32.3-42.2). Language in
Americal's pretreatment permit states, "Unacceptable RTA toxicity is defined as a significant percent
difference between the chronic inhibition concentration (IC25) values for the discharge -spiked test
simulation and the control simulation as determined by a comparison of the 95% percent confidence
limits (B 1)." The report notes that although the confidence interval for the Americal test was broader
than typically observed for RTA tests, test results indicate that Americal's effluent was not contributing
refractory toxicity to final POTW effluent as specified by terms of the pretreatment permit. The
pretreatment permit also requires Americal to pass two consecutive monthly RTA tests to demonstrate
that toxicity reduction measures have been successful. While RTA test results from July and September
tests indicate that this condition was met, the City is concerned about the "apparent toxicity of the
September discharge sample even though it technically passed the test criteria."
City personnel met with Americal representatives on November 5 to discuss the September RTA
test results. At the meeting, Americal agreed to evaluate the use of activated carbon in its pretreatment
facility. Americal will perform carbon treatability testing prior to the upcoming RTA test this quarter.
AUGUST RTA
Sample results from the August RTA testing were considered inconclusive due to biological
growth observed in RTA effluents. Samples were collected from the Harriet and Henderson Cotton
Mills, Burkhart Carolina, and Americal. The report suggests that biological growth was caused by a
component of the RTA test, possibly dilution mock influent wastewater or activated sludge. On June 24,
the City completed repairs to the first stage trickling filters. This action decreased effluent BOD values
from 50 mg/L to 30 mg/L and lowered the F/M ratio in the activated sludge basin. Lower F/M ratios can

3
contribute to pin floc, which t.— _.ty has observed since July 12, and fung— r,.,)wth. The report notes
that biological growth may have been introduced by an industrial discharge. Various organisms such as
bacteria, fungi and bacteria are found in cooling tower blowdown. The report notes a wastewater
treatment plant upset during the week of August 6.
SEPTEMBER RTA
Prior to conducting the September RTA, the City made several corrections to the RTA procedure
to minimize the presence of biological growth. Actions included utilizing a different source of mock
influent (North Nutbush line versus Country Club pump station) and increasing the F/M ratio of the
activated sludge process. The report notes that Harriet & Henderson's South Mill was the only source of
toxicity noted during the September RTA.
QUARTERLY INDUSTRY MONITORING
All major industries were monitored during the quarter and included Americal, Ball Foster,
IAMB, J.P. Taylor and Kennametal. Samples were collected September 20 for a single sample toxicity
test. "Fail" test results were reported for Americal and Ball Foster at their respective flow contributions
to Henderson (6.4% flow for Americal, Ball Foster was tested at 1.0%; whereas, flow contribution is
actually 0.8%). Ball Foster's observed toxicity may have been artifactual since one of the test replicates
died causing the mean young neonate count to be significantly lower than the control. Ball Foster
installed a water recycling system several years ago and actual flow is approximately one-fourth the
permitted flow. Based on Ball Foster's compliance record (no toxicity failures in five years) and
information that no manufacturing or process changes have occurred since the last "pass" test result was
obtained, the City decided to resample the Company's discharge using a P/F test rather than conducting
RTA testing.
SUMMARY
The City's efforts to investigate sewer/industrial monitoring have resulted in the following
conclusions:
➢ Harriet & Henderson's South Mill was identified as an intermittent source of toxicity.
➢ The apparent toxicity of Americal's discharge during September is a cause for concern.
America] has agreed to conduct an evaluation using activated carbon for toxicity reduction.
The City is considering plans to upgrade the WWTP to include biological treatment. Organic
carbon removal and biological nutrient removal are processes which will be considered in the upgrade.
The report notes that if results from biological treatability testing demonstrate that the proposed process
improvements are expected to achieve compliance with Henderson's toxicity limit then the City will
request a waiver of the TRE.
Proposed activities for the upcoming quarter are reasonable.
Our office has several comments concerning the City's TURE work First, we acknowledge the
scope of the current TURF investigations being conducted by the City. The City is considerably more
focused with respect to its THE approach and has gained valuable knowledge on IU discharges to the
POTW. Second, while the current RTA work is providing information regarding sources of refractory
toxicity, we feel that the City's past history of long-term toxicity non-compliance should not be
overlooked. We are curious what action(s) the City will pursue against Harriet & Henderson and if it
plans on visiting the site to verify information provided by the Company. We agree that overlapping
95% confidence intervals obtained for the Americal September RTA testing should be scrutinized and
warrant additional toxicity testing.
The City indicated that they would request a THE waiver if biological treatability testing
demonstrated that the new treatment processes would achieve compliance with the 90% chronic limit.
The City has also submitted a request for an additional twelve months to complete the THE under the

current SOC. We have c ns with supporting the City's request fc tdditional twelve month time
extension to achieve compliance with final permit limits for chronic toxicity.
If you have any questions, please feel free to contact me at 733-2136.
cc: Coleen Sullins -Water Quality Section Chief
Bill Reid -Point Source Branch
Marcia Lieber -Point Source Compliance/Enforcement Unit
Kirk Stafford, Raleigh Regional Office
Tom Poe -Pretreatment
Tom Spain, City of Henderson, PO Box 1434, Henderson, NC 27536
Aquatic Toxicology Unit Files
Central Files

City of Henderson THE Pr ss Report Page 7
NPDES No. 0020559 November 10, 1999
5.2 September RTA
The RTA protocol was modified to minimize the presence of the biological growth observed in
the August RTA. First, another source of mock influent was used for testing. The mock influent
consisted of wastewater collected from the North Nutbush line in lieu of the sampling point for
the August RTA (i.e., Country Club pump station). The city required Omega, an industrial
cleaner distributor, to cease cleaning drums at the carwash that discharges to the North Nutbush
line. Therefore, this potential source of toxicity was eliminated during the sample collection
period. Second, the F/M of the activated sludge process was increased to minimize pin floc and,
perhaps, favorable conditions for fungal growth.
The September testing used samples from the same sources that were sampled for the August
RTA. Results are summarized in Table 2 and Figure 1. A discussion of the Harriet &
Henderson and Americal results are provided in Sections 3 and 4, respectively. Other than
Harriet & Henderson's South Mill, no other sources of toxicity were indicated.
Table 2. Summary of Refractory Toxicity Assessment Results
Sample Location
ChV
Chronic
Sandy Creek P.S.
30
45
37
34.4
14.9
- 35.4
North Cotton Mill
30
45
37
35.4
32.2
- 36.8
South Cotton Mill
15
30
21
19.7
18.7
- 20.8
Americal
15
30
21
11.5
6.7
- 32.3
Burkart
30
45
37
36.8
35.2
- 39.3
Redbud Main Line
30
45
37
52.7
48.4
- 57.4
Redbud Pump Station
15
30
21
30.7
22.6
- 34.6
Control
30
45
37
36.9
32.3
- 42.2
WWfP Final Effluent
90
> 90
> 90
> 90.0
NC**
* 95% confidence intervals
'* not calculable
5.3 Ouarterly Industry Monitoring
Each of the major industries, including Americal, Ball Foster, IAvfs, J.P. Taylor, and
Kennametal were monitored for toxicity in the preceding quarter. Results are summarized in
Table 3.

City of Henderson THE Pi _ ess Report Page 6
NPDES No. 0020559 November 10, 1999
evaluate the use of activated carbon for toxicity reduction. Americal's evaluation will be
performed in parallel with the city's study of carbon treatment at its WWI?. Americal will
perform carbon tests prior to the RTA test to be performed this coming quarter.
5. Sewer and Industrial User Monitoring
The City conducted intensive sewer and industry monitoring in the previous quarter. RTA tests
were performed in August and September to evaluate the toxicity contribution from the Sandy
Creek sewershed and the Redbud main line.
5.1 August RTA
The August testing included samples collected from the two Harriett & Henderson cotton mills,
which are located in the toxic County Home areas. Samples were also collected from Burkart
Carolina, which discharges to the Sagefield line, and Americal. The results of the Harriet &
Henderson and Americal RTA tests are described above in Sections 3 and 4, respectively.
Unfortunately, the results of the August RTA were inconclusive due to an interference in the
toxicity tests performed on the RTA effluents. The interference was the same problem noted for
the Harriet & Henderson and Americal RTA tests (Sections 3 and 4). A biological growth
resembling fungi caused an unusual dose response in the toxicity tests. For example,
Ceriodaphnia dubia reproduction in the RTA control effluent was as follows:
Test Concentration (%): 90% 67.5% 45% 30% 15% Control
C. dubia Reproduction (Mean Young): 0 0 14.6 15.8 9.4 21.6
Mean young production was reduced to nearly equal levels in the 15, 30 and 45% concentrations.
The similarity in results may be explained by an adverse effect of the growth, which was
observed in each of the test concentrations. A review of the results suggested that the growth
was caused by a component of the RTA test such as the activated sludge or mock influent
wastewater used for diluting the sewer/industry samples.
The City has observed pin floc in the aeration basin effluent since the week of July 12''. The pin
floc may be indicative of the recent lower organic loading to the activated sludge process. On
June 24 h, the City completed repair of the first -stage trickling filters. As a result, the effluent
BOD from the trickling filters has decreased from an average of 50 mg/L to 30 mg/L. This
decrease in BOD has lowered the food to microorganism (F/M ) ratio in the activated sludge
basin from 0.05 lb/lb to 0.041b/lb. The lower F/M can contribute to pin floc and, perhaps,
favorable conditions for fungal growth.
The fungi may also have been introduced or promoted by an industrial discharge. Fungi, as well
as algae and bacteria, can be prevalent in cooling water tower blowdown. In addition, the
biological growth may be promoted by treatment process upsets. During the week of August 6th,
the treatment process was upset by an apparent slug loading of inhibitory wastewater. The City
experienced some washout of suspended solids from the clarifiers due to floating floc.

City of Henderson THE P _ ;ss Report Page 5
NPDES No. 0020559 November 10, 1999
4. Americal Corporation's THE
Americal submitted a final THE report and performed RTA tests to confirm that their efforts to
reduce toxicity have been successful. THE reports submitted to the City are presented in
Appendix B. A summary of the final THE report and the RTA test results for this quarter is
provided as follows.
Results of Americal's July RTA test suggested that effluent toxicity has abated. Nonetheless,
Americal continued to evaluate fiuther process changes to ensure compliance with the toxicity
requirement. Americal contacted a chemical vendor about a substitute for a softening agent,
VircoSoft 348 that contains nonyl phenols. In August, this softener was replaced with another
softening agent, SparLube LB50 (manufactured by Spartan), that reportedly does not contain
nonyl phenols.
Following the process changes, Americal conducted a second consecutive monthly RTA test in
August. This test was invalid due to an interference in the toxicity tests performed on the RTA
effluents. TriTest, the laboratory performing the toxicity tests for the RTA, observed what
appeared to be a biological growth in the sample treatments of the toxicity tests. The growth was
not found in the toxicity test controls or in any tests performed for other clients during the test
period. These results suggest that the growth was caused by a component of the RTA test such
as the activated sludge or mock influent wastewater used for diluting the sewer/industry samples.
Another RTA test was performed in September. The test involved comparing the toxicity of
Americal's discharge sample spiked into the city's mock treatment plant influent versus a control
test consisting of the mock influent alone. Although the effluent of the Americal-spiked test was
more toxic than the control effluent (i.e., ChVs of 11.5% versus 36.9%), the confidence intervals
for the tests overlapped (i.e., upper bound of the Americal's test result was the same as the lower
bound of the control test result). It should be noted that the confidence interval for the Americal
test was wider than typically observed for RTA tests. Nonetheless, the results show that
Americal was not contributing refractory toxicity by the terms specified in the discharge permit.
The permit states:
"Unacceptable RTA toxicity is defined as a significantpercent difference between the chronic inhibition
concentration (IC25) values for the discharge -spiked test simulation and the control simulation as
determined by a comparison of the 95 percent confidence limits (BI) ".
According to the discharge permit, Americal must pass two consecutive monthly RTA tests to
demonstrate that toxicity reduction measures have been successful. Both the July and September
RTA tests show that Americal has satisfied this condition. However, the city is concerned about
the apparent toxicity of the September discharge sample even though it technically passed the
test criteria.
On November 5ei, the city met with Americal to discuss the September RTA results. Americal
representatives described current production activities and chemical usage. Based on the city's
concern about the potential toxicity of Americal's discharge, Americal representatives agreed to

City of Henderson THE Pi _ ss Report Page 4
NPDES No. 0020559 November 10, 1999
In September, the city submitted a letter to Harriet & Henderson that described the evidence for
toxic discharges and provided a list of action items for investigating the discharges. The
requirements in the letter constituted the requirements that permitted industrial users would have
to complete if a THE was required. The action items included:
• Providing information on chemical usage at the North and South Henderson Cotton Mills,
including material safety data sheets (MSDS), other available vendor data, chemical usage
rates, and frequency of discharge.
• Requiring submittal of Biocide/Chemical Pretreatment Worksheet —Form PTI01 for all
biocides used at the North and South Mills.
• Completing THE date logs on a weekly basis.
• Providing maps of the sanitary and cooling water sewers at the North and South Mills,
including locations of discharge points (e.g., cooling water and sanitary flows) and the
chemicals used at each location.
• Investigating cooling water losses at the North and South Henderson Cotton Mills to
determine if piping within the facilities is leaking and possibly discharging to the City's
sanitary sewer.
• Determining the characteristics and ultimate disposal method of wastewater from the South
Mill's Zorrella Yarn Conditioner.
• Submitting a copy of the spill prevention and control plans for the North and South Mills.
On October 14a', Harriet & Henderson submitted a letter report on their progress in
accomplishing the action items. The report included MSDS on chemicals used in the mill
HVAC systems, PT-101 forms on all biocides used at the mills, copies of their cooling water
discharge permits, site drawings indicating the sanitary and cooling water discharge points, THE
date logs, and copies of stormwater pollution prevention plans. In their letter, Harriet &
Henderson indicated that they had not found any cross connections between the cooling tower
discharge piping and the sanitary sewer.
In late September, the city performed RTA tests on discharge samples from both Harriet &
Henderson cotton mills. The effluent of the Harriett & Henderson South Cotton Mill test was
more toxic than the control effluent (i.e., IC25s of 19.7 vs. 36.9%,respectively). The 95%
confidence intervals for the IC25 values did not overlap; therefore, the mill sample contained
significant refractory toxicity. Based on these results, the South Mill is considered a source of
refractory toxicity. The city plans to meet with Harriet & Henderson to discuss the implications
of the RTA results and the industry's progress in the TRE.

City of Henderson THE P _ :ss Report Page 3
NPDES No. 0020559 November 10, 1999
2. Pretreatment Program Initiatives
Progress achieved in the preceding quarter includes:
• Identifying a new intermittent source of toxicity, the Harriet & Henderson south cotton mill
(see Section 3)
• Reviewing Americal Corporation's progress in identifying and controlling source(s) of
toxicity at its textile processing facility.
• Receiving weekly chemical usage reports that list daily quantities of chemicals used.
• Continuing to monitor the toxicity of industrial user discharges (see results below).
• Continuing quarterly inspections of major industrial users (i.e., all major industries have been
and will continue to be inspected each quarter).
• Reviewing small industrial users with water usage as low as 15,000 cu. ft. per month.
• Continuing frequent communication with the industries regarding pretreatment activities and
their relationship to toxicity.
In August, the city submitted a synopsis of the industrial waste survey forms to DWQ
Pretreatment Unit. Upon review of the survey forms, the city did not identify any potential
significant industrial users. The survey information was also reviewed with respect to potential
toxic discharges. No such discharges were indicated.
The city reviewed information submitted by Omega Cleaning Products on cleaning products.
This review indicated the potential for discharge of surfactants of concern to the sanitary sewer.
The city notified Omega that cleaning of product containers at the local car wash would not be
allowed. Omega has an onsite septic tank for sanitary wastes.
In October, the City met with IAMs to discuss their progress in meeting the compliance
agreement and consent order (CACO) for phosphorus. IAMB submitted a proposed schedule for
the wastewater treatment plant upgrade.
3. Harriet and Henderson's THE
Results of Toxicity Tracking System (TTS) and Refractory Toxicity Assessment (RTA) tests
performed in May and July indicated intermittent toxicity in the sewer lines serving Harriet &
Henderson's North and South Mills. Harriet & Henderson is authorized to discharge only
sanitary wastes to the city's sewers; therefore, the city was concerned about the possible
discharge of toxic nondomestic wastewater. On August 16m - 17s', the city inspected Harriet &
Henderson's cotton mills (North and South Mills). Further evidence of nondomestic discharges
was obtained.

City of Henderson THE P -ss Report
NPDES No. 0020559
Introduction
Page 2
November 10, 1999
This quarterly progress report is prepared and submitted to meet the November 15"' date
specified by Section 2(b)2 of the City of Henderson's draft Special Order by Consent (SOC
EMC WQ No. 96-05). This report describes the progress made in the last quarter (August 16
through November 15, 1998), the plans for the next quarter, and any significant issues that may
delay progress in completing the TRE.
Progress in the Preceding Quarter
I. Results of WWTP Effluent Toxicity Monitoring
A total of three toxicity compliance tests were performed in the preceding quarter. Monthly
effluent monitoring was performed, as required by the SOC. Results are summarized in Table 1.
Table 1. Summary of Monthly Compliance Test Results
Sample Collection Dates Test Initiation Date ChV (%)
Aug 16-17 and Aug 18-19 Aug 18 21.2
Sep 6-7 and Sep 8-9 Sep 8 77.9
Oct 25-26 and Oct 28-29 Oct 27 21.2
As with previous tests, these results show a wide variability in effluent toxicity (see Appendix
A). Following the July compliance test, which showed no chronic toxicity, the August effluent
sample was relatively toxic. Again, after the September compliance test, which showed
relatively low toxicity, the October effluent sample was toxic. These data indicate an
intermittent source of toxicity. The city recently identified an intermittent source of toxicity and
results of the industrial user's investigation of the cause(s) of toxicity are described below.
Results of a Phase II Toxicity Identification Evaluation (TIE) test of a toxic June effluent sample
were inconclusive. Although toxicity was recovered from the initial C 18 solid phase extraction
(complete mortality in 24-hours in the methanol eluate corresponding to 400% effluent), toxicity
was not recovered from the high performance liquid chromatography (HPLC) column. No
chronic effect was observed in any of the 30 methanol fractions eluted from the HPLC column
and tested at 165% effluent. These results suggest that the toxicant(s) was spread out among the
fractions and therefore, not readily detected. Surfactants have this characteristic; however,
additional testing is needed to confirm this conclusion.

Progress Report
for the Toxicity Reduction Evaluation
at the City of Henderson's Nutbush Creek Wastewater Treatment Plant
NPDES No. NCO020559
August 16 through November 15, 1999
Submitted In Fulfillment of the Special Order by Consent
EMC WQ No. 96-05
Prepared for
Department of Environment, Health and Natural Resources
3800 Barrett Drive, Suite 100
Raleigh, North Carolina 27609
Prepared by:
City of Henderson
P.O. Box 1434
Henderson, NC
With Assistance by:
Aquatic Sciences Consulting
15751 Bushy Park Rd
Woodbine, Maryland 21797

City of Henderson THE Pr _ ss Report
NPDES No. 0020559
N 15
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Page 8
November 10, 1999
Sandy North South America] Burkart Redbud Redbud Control VWVfP
Creek P.S. Cotton twill Cotton Mill Main Line Pump Final
Station Effluent
Sampling Location
Figure 1. Inhibition Concentrations Values for the September RTA Tests
Table 3. Quarterly Monitoring Results for Major Permitted Industries*
Industry Test Concentration** Pass/Fail Result
Americal
6.4%
Fail
Ball Foster***
1.0%
Fail
IAMB
6.6%
Pass
J.P. Taylor
1.6%
Pass
Kennametal
0.8%
Pass
' Samples collected September 20 for single sample test.
Equivalent to flow contribution to the City's treatment plant.
Ball Foster's sample was inadvertently tested at 1.0% instead of the flow contribution of 0.8%
The momtormi results indicate that Americal was contributing raw wastewater toxicity in
September (20 - 21'); however, the RTA test performed by Americal in September (22nd - 241')
showed no refractory toxicity contribution (see Section 4 above). Ball Foster's discharge was
also toxic. However, the apparent toxicity may have been an artifact of the test. One of the ten
replicates of the test concentration died, which caused the mean young value to be significantly

City of Henderson THE Pr _ _ss Report Page 9
NPDES No. 0020559 November 10, 1999
lower than the control (i.e., 23.92 vs. 31.17, respectively). If this replicate is removed, the mean
young value (26.1) would not be significantly lower than the control value.
Ball Foster installed a water recycling system several years ago and as a result their current flow
is actually less than one -quarter of their permitted flow (i.e., 5,000 vs. 23,000 gpd). Therefore,
the toxicity test concentration, which is based on their permitted flow, is overly conservative.
Also, Ball Foster has not failed a toxicity test since monitoring of their discharge began more
than five years ago. In addition, Ball Foster has not changed their manufacturing process or
chemical usage since the last toxicity test, which was a "pass".
The city has decided to carefiilly evaluate Ball Foster's discharge together with other, more
significant, sources of toxicity. However, based on the above considerations, Ball Foster's
discharge will be retested as soon as possible using the pass/fail test procedure, rather than
proceeding to relative costly refractory toxicity assessment (RTA) testing.
5.4 Summary
The City's sewer/industry monitoring effort has yielded the following conclusions:
• Harriet & Henderson's South Mill was identified as an intermittent source of toxicity.
• Although Americal's September discharge sample technically passed the test criteria, the
apparent toxicity of the sample is cause for concern. Due to the city's concern, Americal
has agreed to perform an evaluation of the use of activated carbon for toxicity reduction.
Based on these conclusions, the City has developed a preliminary plan to control the sources of
toxicity as described below.
6. Biological Treatability Testing
The city is in the process of considering plans for an upgraded W WTP, which will include a new
biological treatment system. The general design of the biological treatment process will be a
multi -stage process that includes both organic carbon removal and at least some biological
nutrient removal. The current design allows for a hydraulic retention time of 16 hours in aerobic
treatment, which may oxidize toxicants.
Although the new process will consist of several stages, the stage that is likely to achieve the
greatest toxicity reduction is the aerobic stage. The city is in the process of testing the aerobic
process in a simple bench -scale, "fill and draw" study. The testing involves treating the W WTP
influent with the current activated sludge for a sufficient period of time to establish a biomass
that is similar to the activated sludge of the new aerobic stage. In September, the study was
started by adding W WTP influent, together with the city's biomass, to two replicate aerobic
bioreactors. Each day, the air is stopped, the biomass solids are settled and the effluent is
withdrawn and discarded. Excess biomass solids are wasted as necessary, a new WWTP influent
sample is added and the bioreactors are aerated again. It will be necessary to perform the fill and

City of Henderson THE R-,s.,;ss Report Page 10
NPDES No. 0020559 November 10, 1999
draw treatment for several months (at least two sludge ages) to ensure that the biomass is
acclimated to the process.
Bioreactor samples collected after a few weeks of treatment were toxic. However, it is possible
that the process had not yet stabilized. Once the city is confident that the process has stabilized,
the city will collect additional effluent samples for toxicity testing. The results will be reviewed
to examine the capability of the new process for achieving the discharge permit limit for toxicity.
If results demonstrate that the new treatment process is expected to achieve compliance with the
toxicity limit, the city will request a waiver of the TRE.
Plans for the Next Quarter
The City plans to conduct the following work in the next quarter (November 16, 1999 through
February 15, 2000):
1. Chronic C. dubia compliance tests will be performed each month as specified in the SOC.
2. The City will meet with Harriett & Henderson to discuss the results of their investigation into
cross connections to the sanitary sewer, biocide usage, and the refractory toxicity of the
South Mill discharge sample collected in September. The city will request Harriett &
Henderson to submit a THE plan with an implementation schedule.
3. Americal will be required to perform a follow-up RTA test to confirm the reported toxicity
reduction. The city will also review America's evaluation of activated carbon as a toxicity
reduction method.
4. The City will continue to monitor for potential sources of toxicity in the Sandy Creek
sewershed and the Redbud main line.
S. The City will inspect all major industrial users in the next quarter. During the inspections,
the City will focus again on activities that can be performed to help minimize the discharge
of toxicity.
6. The City will conduct another Phase 11 TIE test on a toxic effluent sample. This test will
involve passing a very large volume of effluent sample through the C 18 column to
concentrate the toxicants as much as possible. Concentrating the sample may allow detection
of the toxicants when they are fractionated on the HPLC column.
7. The City will continue to evaluate the toxicity reduction capability of the proposed treatment
plant upgrade.

Appendix A
Historical Ceriodaphnia dubia Chronic Toxicity Data
for the Nutbush Creek WWTP Effluent

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Appendix B
Americal Corporation
Toxicity Reduction Evaluation Reports

Aquatic Sciences Consulting 15 75 1 Bushy Park Rd
Woodbine, Maryland 21797
[phone] phone
[phone] fax
October 11. 1999
Mr. Jeff Golliher
Superintendent of Dyeing
Americal Corporation
P.O. Box 1419
Henderson, NC 27536
Re: Results of Refractory Toxicity Assessment (RTA)
Dear Mr. Golliher:
In September, a Refractory Toxicity Assessment (RTA) was performed to confirm the toxicity
reduction observed in Americal's discharge in July. This test was a follow-up to the August RTA
test, which was inconclusive due to a test interference. September's RTA test was performed to
meet the permit requirement for consecutive monthly RTA tests. The results of this testing are
described as follows.
Summary
Aquatic Sciences Consulting (ASC) performed the RTA test on September 23rd and 24t° at the
city's Nutbush Creek Wastewater Treatment Plant (WWTP). Test procedures followed those
used in earlier RTA tests performed in January, February, July and August of this year. The test
involved comparing the toxicity resulting from treatment of Americal's discharge sample spiked
into the city's mock treatment plant influent versus a control test consisting of the mock influent
alone.
Although the effluent of the Americal-spiked test was more toxic than the control effluent (i.e.,
ChVs of 11.5% versus 36.90/o), the confidence intervals for the tests overlapped (i.e., upper
bound of the Americal's test result was the same as the lower bound of the control test result). It
should be noted that the confidence interval for the Americal test was wider than typically
observed for RTA tests. Nonetheless, the results show that Americal was not contributing
refractory toxicity by the terms specified in the discharge permit.
According to the discharge permit, Americal must pass two consecutive monthly RTA tests to
demonstrate that toxicity reduction measures have been successful. Both the July and September
RTA tests show that Americal has satisfied this condition (Note that the August rest was invalid).

Jeff Golliher Page 2
America] Corporation October 11, 1999
However, in consideration of the near failure of the test, it is recommended that an additional
chemical review be performed. Americal has noted that much of the bleaching operation has
been transferred to the Franklinton facility. hi the meantime, the dyeing operation has been
increased. Therefore, the composition of the wastewater has changed, which may have had an
effect on the RTA results. The results of the review, including recommendations for further
testing and/or chemical substitutions, should be documented in a brief report. Once the
recommendations have been implemented, tests should be performed on the discharge to confirm
compliance with the toxicity limit.
Technical Approach
Sampling
There was an error in collecting the composite sample of Americal's discharge on September 22°d
- 23`d. Americal was notified to collect one (1) gallon of their discharge; however, the city was
advised that two (2) gallons would be collected (error was made by the consultant). When the
city arrived on September 23`d (9AM) to pick up the sample, only about one gallon was in the
sampler bottle. The city started the sampler and pumped about one more gallon into the sampler
bottle. Therefore, the sample consisted of about one gallon of 24-hour composite sample and
one gallon of grab sample. Normally, a 24-hour composite sample is used to initiate the RTA
test (I n day) and a portion of the sample is saved and used again on the second day of testing. In
this case, however, the combined composite/grab sample collected on a Septemb--r 22°d - 23`d
was used for the first day of the test and a second full 24-hour composite sample of Americal's
discharge (collected on September 23 d - 24 h) was used for the second day of the test. It should
be noted that on September 23`d the city observed that the grab sample was darker in color than
the composite sample.
Samples from the North Nutbush line and WWTP return activated sludge (RAS) line were also
collected for the RTA. The North Nutbush line sample was a 40 gallon 24-hour composite
collected on September 22°d - 23`d. This sample was used for both the first and second days of
testing. Insufficient sample was available for the second day of RTA testing; therefore, an
additional 10 gallon grab sample was collected on September 24d' and added to the composite
sample. The RAS sample was a 10 gallon grab collected at 1 PM on September 23`d.
RTA Tests
Test procedures followed the protocol given in Appendix A.
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Jeff Golliher
Americal Corporadon
Page 3
October 11, 1999
Previous RTA tests suggest that a constituent(s) in the WWTP influent may be masking the
measurement of toxicity in the RTA. Therefore, as recommended in EPA's upc::ed Municipal
THE Protocol (Draft 1999), a "mock" influent was used instead of the WWTP influent to
eliminate this possible masking effect. The mock influent consisted of wastewater collected
from the North Nutbush line, which collects largely domestic wastewater. This location was
used again in lieu of the sampling point for previous RTA tests (i.e., Country Club pump station)
because of concerns about fungal contamination. The city required Omega, an industrial cleaner
distributor, to cease cleaning drums at the carwash that discharges to the North Nutbush line.
Therefore, this potential source of toxcity was eliminated during the sample collection period.
The RTA treatment step normally reveals the source(s) of refractory toxicity, including toxicity
caused by treatment byproducts; however, it is possible that the toxicants may be present only
after long-term treatment (i.e., greater than the 4-hour treatment time in the WWTP activated
sludge process). The precursor chemicals) may accumulate in the activated sludge and
breakdown slowly over time to the toxicant(s) of concern. Some surfactants breakdown slowly
to form toxic byproducts. The RTA procedures were adjusted to account for this potential case.
The modified RTA approach involved "fill and draw" treatment using multiple samples instead
of the conventional approach of treating a single sample. The activated sludge biomass used in
the first "fill" step is saved and used in the second "fill" step. In this way, residual chemical
concentrations and/or treatment byproducts can accumulate in the biomass and L: ay be detected
in toxicity tests of treated samples. This protocol was used in Americal's toxicity study in
January, February, July and August 1999.
The RTA tests utilized two types of simulations: one treating the mock WWTP influent and the
other treating mock WWTP influent spiked with sewer/industry samples. The sewer/industry
spike volumes were based on the percent flow values for each sampling location. The spike
volumes and other RTA components are listed in Appendix B (Table B-1).
Results
RTA Tests
Results of the RTA operating conditions and toxicity tests are presented as follows.
CAMy Documents\Word DocsVohn's Work\lobs\Amerlca]\RTA Round 5\Rq*rt (Oct I1).doc
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Jeff Golliher Page 4
Americal Corporation October 11, 1999
Simulation Opgrating Conditions
A summary of the RTA operating conditions is provided in Appendix B (Tables'3-2 and B-3).
This summary includes general conditions for the trickling filter and nitrification simulation
steps.
In general, the simulations effectively replicated the operating conditions of the trickling filter
and activated sludge processes at the City's WWTP. After set up, the dissolved oxygen levels in
the RTA bioreactors were set to >4 and > 10 mg/L for the first aeration step (air supply) and
second aeration (oxygen supply), respectively. These levels are typical for air -supplied and pure
oxygen -supplied nitrification treatment processes and the city usually maintains a >10 mg/L
oxygen level in its pure oxygen activated sludge process.
On Day 2, it was necessary to add lime to the reactors to maintain the pH within an acceptable
range for nitrification treatment (i.e., above 6.7). Approximately 360 to 411 mg of quick lime in
a slurry solution was added to the reactors, which resulted in a 45 to 51 mg/L concentration in the
mixed liquors. This amount of lime maintained the pH within 6.8 to 7.3 for the Americal-spiked
reactor and 7.0 to 7.3 for the control.
No significant differences in chemical oxygen demand (COD) removal were observed between
the Americal-spiked test and the control (see Table B-4). On the first day of testing, the effluent
COD concentration of the nitrification process effluent was similar for the spikeu and control
tests (<25 mg/L, respectively). These results indicate similar treatment of the Americal-spiked
and control samples. On Day 2, the effluent COD concentration of the spiked and control tests
was also relatively similar (24 and 40 mg/L, respectively), which indicates similar treatment
performance. However, the COD level of the control trickling filter effluent on Day 2 was more
than double the COD level of the Americal-spiked treatment. Foaming was observed during
trickling filter treatment of the control sample. It is possible that the foaming was caused by
detergent residues from washing the filter column. The detergent would impart a relatively high
COD.
Toxicity Test Results
Toxicity results are presented in Table 1. Results of the Americal-spiked test are compared to the
control results. Although the effluent of the Americal-spiked test was more toxic than the control
effluent (i.e., ChVs of 11.5% versus 36.9%), the confidence intervals for the tests overlapped
(i.e., upper bound of the Americal's test result was the same as the lower bound of the control test
CAMy Documents\Word DmVohn's WorkVobs\HmericaPaTA Round RReport (Oct 11).doc
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Jeff Golliher
Americal Corporation
Page 5
October 11, 1999
result). It should be noted that the confidence interval for the Americal test was wider than
typically observed for RTA tests. Nonetheless, the results show that Americal was not
contributing refractory toxicity by the terms specified in the discharge permit. 1 he permit states:
"Unacceptable RTA toxicity is defined as a significant percent difference between the chronic
inhibition concentration aC25) values for the discharge -spiked test simulation and the control
simulation as determined by a comparison of the 95 percent confidence limits (BI) ".
Given that the test nearly failed, it is recommended that Americal perform an additional review
of chemicals used in the dyeing process and follow-up toxicity tests on the discharge.
Table 1. Summary of Refractory Toxicity Assessment Results
Test Limited -scale C. dubia Chronic Endpoints
NOEC LOEC ChV IC25 (C.I.)*
Americal 15 30 21 11.5 (6.7 - 32.3)
Control 30 45 37 36.9 (32.3 - 42.2)
' 95% confidence intervals
Please call me [phone], if you have questions or comments about this report.
Sincerely,
John A. Botts
Principal Scientist
CAMy DocumentMord DocsUohn's WorkVobsWnerica1\RTA Round AReport (Oct I1).doc
10/12/99 1:52 PM

Appendix A
Refractory Toxicity Assessment Procedures for the Americal Study

America] Corporation Page A-2
Appendix A - RTA Procedures October 11, 1999
Refractory Toxicity Assessment Procedures for the Americal Study
Results of in -plant monitoring at the City's Nutbush Creek W WTP show no decrease in
toxicity after treatment (in the aeration tank) and sometimes an increase in toxicity. At
the same time, little or no toxicity has been found in raw wastewater samples collected
from the Sandy Creek sewershed, the area where toxicity appears to be originating.
These results suggest that toxicity may be manifested only after treatment.
The RTA treatment step normally reveals the source(s) of refractory toxicity, including
toxicity caused by treatment byproducts; however, no clear source(s) of toxicity has been
recently identified by the RTA approach. It is possible that the toxicants may be present
only after long-term treatment (i.e., greater than the 4-hour treatment time in'the WWTP).
The precursor chemical(s) may accumulate in the activated sludge and breakdown slowly
over time to the toxicant(s) of concem. Some surfactants breakdown slowly to form
toxic byproducts. An adjustment in the RTA procedures was, therefore, needed to
account for this potential case.
The general RTA approach was modified to evaluate potentially toxic breakdown
products. This approach involved "fill and draw" treatment using multiple samples
instead of the conventional approach of treating a single sample. The activated sludge
biomass used in the first "fill" step was saved and used in the second "fill" step. In this
way, residual chemical concentrations and/or treatment byproducts could accumulate in
the biomass and might be detected in toxicity tests of treated samples.
RTA treatment simulated the main treatment processes at the Nutbush Creek WWTP,
including trickling filtration, nitrification, and filtration. Although, hydrogen peroxide
(HZOZ) is currently being added at the Nutbush Creek W WTP, this oxidant was not added
in the RTA because the City is interested in reducing and eliminating the use of H202.
Also, a coarse glass -fiber filter was used in lieu of a bench -scale tertiary filter column
because a previous study had shown that filtration using glass -fiber filters provides
similar results compared to granular media filtration (Aquatic Sciences Con_+.lting,
1998).
The first "fill and draw" step, referred to as the "Toxicant Accumulation Protocol", was
performed as follows:
1. Two and one-half (2 '/2) gallon samples of Americal's pretreatment facility effluent
and North Nutbush line sample were collected on September 22nd -23`d. The North
Nutbush line sample was used as the "mock influent" for the control test. This test
was compared to the Americal-spiked test, which consisted of the Americal sample
spiked into the North Nutbush line sample. A portion of the North Nutbush line
sample was saved and used on the second day of testing. A second Americal sample
was collected on September 23`d - 24d' and used on the second day of testing.

America[ Corporation
Appendix A - RTA Procedures
4—
Trick
C
(with r
Page A-3
October 11, 1999
staltic
amp
Figure B-1. Schematic of Trickling Filter Column Simulation
2. Wastewater samples were passed through columns, which simulated the WWTP
trickling filter process (see Figure B-1). The trickling filter columns consisted of
4-inch diameter, 3-ft PVC columns filled with stone media collected from one of the
WWTP trickling filters. A peristaltic pump fed samples to the columns in a
downflow mode. The column effluent was collected and recirculated to the top of the
column over a 2 hour period. This retention time was selected based on an earlier
study (Aquatic Sciences Consulting, 1997) that showed this treatment period to be
comparable to the WWTP process.
Following trickling filter treatment, the humus solids (fixed film biomass that washed
off the rocks) were allowed to settle and the supematant was decanted for further
treatment by activated sludge (see Figure B-2).

Americal Corporation
Appendix A - RTA Procedures
Wastewater and
Return Activated Sludge
Plastic or
Container
Control Reactor
POTW Influent
(Control)
Air Supply
(Oil -Free)
Air Line
Tubing
Au Stone
Page A-4
October 11, 1999
Spiked Reactor
Sewerlindustrial
Wastewater. ';Piked
Into POTW Influent
Figure B-2. Schematic of Activated Sludge Nitrification Simulation
4. The RAS was rinsed with distilled water to remove potential toxicants before use in
testing. An 11.5-gal RAS sample was added to a 40-gal container, 8 gal of distilled
water was added, and the mixture was aerated for about 1 hour. RAS solids were
allowed to settle and the supernatant was decanted and discarded. The rinsed RAS
was dispensed into 2 % gal plastic reactors. The initial suspended solids
concentration was about three times the average mixed liquor suspended solids
(MLSS) concentration of the City's aeration treatment system (i.e., 3,500 mg/L • 3).
5. Wastewater samples were added to the reactors in three additions over about a 15-
hour treatment period. The final volume of wastewater resulted in a MLSS
concentration that approximated the MLSS concentration of the City's process.
6. Air was supplied to the reactors during the treatment period to maintain a dissolved
oxygen concentration of 2 to >4 mg/L.
At the end of the 15-hour treatment period, the air was stopped and the mixed liquor
was allowed to settle. The supernatant was decanted and tested for COD.
8. The settled activated sludge biomass was saved and used for the second "fill and
draw" treatment step.
The second "fill and draw" step, referred to as the "RTA Protocol", was used to assess the
refractory toxicity of the second Americal sample collected for the study. Samples were
treated and tested for refractory toxicity using the procedures outlined below:
1. The second sample volume (North Nutbush and Americal samples collected on Day 1
and Day 2, respectively) was treated in trickling filter columns using Steps 1 and 2

Americal Corporation
Appendix A - RTA Procedures
Page A-5
October 11, 1999
noted above. The trickling filter effluents were prepared for activated sludge
treatment.
2. The RAS saved from the above Toxicant Accumulation Protocol (Steps 3-6) was
added to the activated sludge reactors.
3. Wastewater samples (total volume) were added to the reactors. The resulting MISS
concentration approximated the MLSS concentration of the City's treatment process.
4. Oxygen was supplied to the reactors by a pressurized tank. A dissolved oxygen
concentration of >2 mg/L was maintained for the first hour of the 4-hour treatment
period. In the remaining 3 hours, the dissolved oxygen level was set to >10 mg/L
5. It was necessary to add lime to the reactors to maintain the pH within an acceptable
range for nitrification treatment (i.e., above 6.7). Approximately 360 to 411 mg of
quick lime in a slurry solution was added to the reactors, which resulted in a 45 to 51
mg/L concentration in the mixed liquors. This amount of lime maintained the pH
within 6.8 to 7.3 for the Americal-spiked reactor and 7.0 to 7.3 for the control.
6. At the end of the 4-hour treatment period, the oxygen was stopped and the mixed
liquor was allowed to settle. The supernatant was decanted and filtered through a
coarse glass -fiber filter (2.7 µm pore size). The filtered samples were shipped
ovemight to the laboratory for testing. The samples were tested for toxicity using a
limited -scale Ceriodaphnia dubia chronic test. C. dubia tests utilized five effluent
concentrations (100, 75, 50, 25, and 12.5%) and a control with 5 replicates per
concentration. Each RTA sample was used for test initiation and renewal on days 3
and 5 of the toxicity test. Samples were held at 4°C between test renewals.
Data Evaluation
The results of the simulation spiked with the Americal discharge sample were compared
to the control simulation results. Evidence of refractory toxicity would be provided if the
effluent toxicity of the spiked simulation is greater than the effluent toxicity 6f the control
simulations.

Appendix B
Refractory Toxicity Assessment Operating Conditions

Table B-I. Components for the Trickling Filter and Oxygen -Nitrification Simulations - September RTA'
Trickling Filter Components (liters)
Nitrification Components
(liters)
1 cst
Industry/Sewer
Mock Total
Trickling Filter
Nitrification
Total
Discharge
WWTP Volume
Effluent Volume
Sludge
Volume
Wastewater
Influent
Volume+
Mock W WTP Influent (Control) (1st & 2nd day)"
0.000
8.00 8.00
5.36
2.640
9.00
Americal (lstday)
0.512
7.49 8.00
5.36
2.640
8.00
Americal (2nd day)
0.512
7.49 8.00
5.36
2.640
8.00
' RTA protocol involved two days of treatment; Ist day was "Toxicant Accumulation Step" and 2nd day was "RTA Step" (see Appendix A)
Nitrification sludge biomass used on I st day of treatment was saved and used on the 2nd day of treatment.
•' Collected from North Nutbush line.
+ Collected from the return sludge line.

Table B-2. Operating Conditions for the Trickling Filter, Nitrification and Filtration
Processes
Parameters VWIrrP Operation* RTA Simulation
Trickling Filter
Hydraulic loading rate 2.1 gal/hour/cu ft media 300 gal/hour/cu ft media
Hydraulic retention time 3 hours 35 min 2 hours
Surface Area (sf) 10,053 0.09
Filter media size 2 - 6 inches 2 - 6 inches
Filter media depth 5 ft 3 ft
Activated Sludge
Flow (MGD) 3.0 N/A
Dissolved oxygen profile >10 mg/L >10 mg/L
Hydraulic retention time 4 hours 4 hours
Mixed liquor suspended 3,500 mg/L 3,200 - 3,500 mg/L
solids (MLSS)
Filtration
Media Sand Coarse glass -fiber filter
Effective pore size NA 2.7 µm
* Based on current W WTP flow of 2.5 mgd.

Table B-3. Operating Conditions for the Activated Sludge Stage
of the RTA
Operating Conditions
Treatment Stage Dissolved pH MLSS
Oxygen (mo/L) (S.U.) m /L)
Day 1 - Air Supply
Americal-spiked Reactor 2 to >4 > 6.9 NA'
Control Reactor 2 to >4 >6.9 NA
Day 2 - Oxygen Supply"
Americal-spiked Reactor 4 to >10 6.8 to 7.3 3,500
Control Reactor 4 to >10 7.0 to 7.3 3,200
NA - not analyzed. MLSS for Day 2 was assumed to be similar to Day 2.
'* 7 to 8 mL of a 5.1% lime solution was added in increments to each reactor over
the 4 hour treatment period.

Table B-4. Removal of Chemical Oxygen Demand (mg/L) in RTA Tests
RTA Test
Treatment Stage Americal Spike Control
Day 1
Trickling Filter Effluent 61 53
Aeration Effluent (unfiltered) < 25 < 25
% Removal > 59 > 53
Day 2
Trickling Filter Effluent* 69 158
Aeration Effluent (filtered) 24 40
% Removal 65 75
* Foaming was observed in the control trickling filter effluent. See text for explanation. ,

CI Y OF HENDERSGI 14
Post Office Box 1434
180 Beckford Drive
Henderson, North Carolina 27536-1434
Phone: [phone] FAX: [phone]
Mr. Ken Schuster
Raleigh Regional Supervisor
NC DENR DWQ
1628 Mail Service Center
Raleigh, NC 27699-1628
Re: City of Henderson Nutbush Creek W WTP
NPDES #NC0020559
SOC-EMC WQ No. 96-05
November Quarterly THE Report
Dear Mr. Schuster,
November 9, 1,1009
I'
h�I' lul7rl i �1
I am forwarding our November Quarterly Toxicity Reduction Evaluation (TRE) report
as required by our SOC.
The City is anxiously awaiting a decision from the Division of Water Quality on our
requested extension of the toxicity compliance deadline in our SOC.
If you have any information regarding our SOC or any questions, please contact me at
[phone].
Sincerely,
Thomas M. Spain
WWTP Director
C: Eric Williams, City Manager
Mark Warren, ACM
Reggie Hicks, Lab Supervisor
Judy Garrett, DWQ-RRO
Kirk Stafford, DWQ-RRO
Matt Matthews, DWQ-ATU
Kevin Bowden, DWQ-ATU
Tom Poe, DWQ Pretreatment
Dana Folley, DWQ Pretreatment
John Botts, Aquatic Sciences Consulting
Files

DIVISION OF WATER QUALITY
RALEIGH REGIONAL OFFICE
WATER QUALITY SECTION
November, 1 1999
MEMORANDUM
To: Coleen Sullins
Water Quality Section Chief
From: Kenneth Schuster, RE�
Regional Water Quality Supervisor
Kirk Stafford
Environmental Chemi
Subject: City of Henderson
SOC EMC WQ 96-005
Amendment Request
NPDES Permit NCO020559
Vance County
Raleigh Regional Office
Please find enclosed a letter for your consideration and signature concerning the subject
SOC amendment request. The City has requested an amendment to the subject SOC to extend the
modified toxicity limit for one year. The limit was relaxed from PASS/FAIL at 90% to Full
range -monitor only. The present order also allows for an upgrade of the Redbud pump station
which is progressing as per the SOC.
The City initially had a JOC issued in 1988. There were several amendments made to
that JOC. After the expiration of the JOC a request was originally made for an SOC in 1996. In
the following years, there were several subsequent SOC amendment requests made and before a
signed SOC could be finalized new amended dates of final compliance were requested and
discussed. The present SOC was signed March 10, 1999.and request was recently requested to
amend the SOC to extend the compliance date for toxicity compliance.
An Up -front penalty of $5140.00 was requested and paid for failure to achieve
compliance for toxicity in JOC 88-04.
The present SOC signed in March of 1999 allows the City to accept 352,510 gpd of
additional wastewater to the WWTP. The Order requires the City to continue the THE plan, and
to comply with permit limits, including toxicity, by September 30, 1999. The Order also requires
the City to reduce I/I and/or upgrade the Redbud pump station to eliminate future overflows at
this location. The City is progressing to Phase II of the pump station upgrade/expansion and
construction of a new conveyance to the W WTP.
y-�

The following is a brief history of the Orders issued to the City:
JOC 88-04 Signed 6/27/88.
JOC 88-04ADI Signed 4/2/90. Includes the permit limits and conditions in accordance with new
NPDES Permit which became effective September 1, 1989. This permit had limits added for
chronic toxicity and other pollutant parameters for which the JOC had to meet compliance. It
also had monitoring requirements for chronic toxicity.
JOC 88-04 ADII Requested 4/21/94. Includes date changes in accordance with the approved
THE for toxicity. This had a requirement to achieve compliance with final effluent limitation for
chronic toxicity by March 1, 1996.Our file copy is a signed copy.
JOC 88-04 ADM Requested 11/8/94. Includes date changes for submittal of conclusions and
method reduction for effluent toxicity. This addendum also had the requirement for a TRE,
headworks analysis, a long term monitoring program for industrial users, and a waste survey
requirement. The final chronic toxicity compliance requirement stayed at March 1, 1996. Our
file copy is an unsigned JOC.
On 2/29/96 an application was received for an SOC requesting a final toxicity compliance date of
3/1/97 . Prior to actual signature of the initial SOC request, the City worked towards compliance
of the requested compliance date of 3/l/97. This date was not met.
The above date was not met and a subsequent verbal date for compliance of 6/98 was made. It
was verbal, in that the SOC processing was not completed in the meantime. This date passed
without compliance and a new date of 3/31/99 was requested.
SOC 96-005 was actually signed on March,l1 1999 with a compliance date of September 30,
1999. They failed to achieve compliance with permit toxicity by this date as required. The
above date was not met and a subsequent date for compliance of 9/30/99 was made. This date
passed without compliance and a new date of 9/30/00 has been requested.
The RRO believes that ample time has been allotted the City to come into compliance
with their chronic toxicity permit requirements. At this time the pretreatment unit is reviewing
for Henderson's compliance with the pretreatment requirements. The RRO may recommend
stipulated penalties at a later date. The new toxicity enforcement policy is now in effect. A disc
is included with this memo with the changes for your convenience.
DWQ staff last met with the City on September 23, 1999 to discuss this matter. At that
time some additional information was requested and a written response to those questions has
been made by the City. Most of that information is connected with the pretreatment review
being made.

ty of Henderson
Office of
P. O. Box 1434 City Manager
180 Beckford Drive Eric M. Williams
Henderson, NC 27536
[e-mail]
Phone:[phone] Fax:[phone]
October 1s`. 1999 "
VIA FACSIMILE TO: 919/57IA718—ORIGINAL TO FOLLOW
Mr. Ken Schuster
Regional Supervisor
Raleigh Regional Office
Department of Environment
and Natural Resources
1628 Mail Service Center
Raleigh, North Carolina 27699-1628
RE: Follow Up from our Meeting on Thursday, September 23rd
City's Request for One Year Extension to Chronic Toxicity Compliance
Special Order by Consent EMC WQ No. 96 05
City of Henderson and NCDENR
Dear Mr. Schuster:
Please accept this as our promised written follow up to the discussion and
questions raised during our meeting with you and a number of NCDENR Staff in
your conference facilities on Thursday, September 23`d. Again, we appreciate your
courtesies in arranging for our ongoing discussions and efforts relative to full and
complete compliance with all conditions in our above referenced SOC.
In addition to the information we provided in advance of the above meeting
(our hand delivered information dated September 22"d ... including the "Demonstration
of Toxicity Treatment Performance" analysis from Aquatic Sciences and the
"Background Information and Justification" submission) further requests were made
during our joint meeting.
A) Question from the Regional Supervisor — Mr. Schuster, toward the end
of our meeting, posed the general question something along the lines of
"How do you fee/ about where the City of Henderson stands now
relative to progress on the chronic toxicity issue versus where you
were a few years back and from your perspective (as City Manager)
how has the City generally managed its activities relative to this
ongoing concern?"
The information sought by your question is very much to the point and, to
briefly recap my response during our meeting, I am pleased to note
the following:
H:Vetterslschuster 10-1-99.doc
Page 1 of 11

I advised I felt we were much further along toward solving our
chronic toxicity problem, but to achieve 'full and complete
compliance" by the September 30th current date in the SOC
seemed highly problematic, especially with regards to regular
consistency in our test results and as we were still "honing in on"
the potentially several locations causing our problems. I advised
felt the one year extension was not only justified, but (at least
in my opinion) the proper course of action for both the City
and the State.
As evidence of both our most recent progress (and my optimism
that a one [1] year extension would prove beneficial), I reported on
several accomplishments from my perspective as City
Manager, including:
• The hiring of an Assistant City Manager for Utility
Operations (Mr. Mark Warren, whom you now and has been
very active in our meetings and discussions over the past
couple of years) in late 1997. This provides an additional,
and critical, level of management and oversight for our utility
operations, including the Wastewater Treatment Plant
directed by Mr. Tom Spain, Mr. Warren reports directly to
me and I, in turn, to the City Council. This arrangement
helps strengthen our organization wide efforts in the
wastewater area.
Transferring the Pretreatment Program from our
Engineering Office to the Wastewater Plant in January, 1998
and designating Mr. Reggie Hicks as the Pretreatment
Coordinator. This move also helps focus and provide daily
concentration on our pretreatment operation generally,
including toxicity compliance.
• The hiring of a Chief Plant Operator at the Wastewater
Plant (Ms. Linda Leyen) in mid 1998 who reports directly to
WWTP Director Mr. Tom Spain. This position provides
increased focus and expertise over operations at the
Wastewater Plant.
• Providing additional Staff resources to the Wastewater
Treatment Plant Laboratory (as needs and circumstances
dictate) to ensure the Laboratory functions effectively and
efficiently with respect to the Wastewater Treatment
operations, including our Toxicity Program.
H:Vetterslschuster 10-1-99.doc Page 2 of 11

Engaging the Consulting Engineer firm of McKim &
Creed, in January, 1998, to prepare an overall analysis and
master plan for our Wastewater Treatment operations, which
was completed in April, 1999 and for which funding is now
being sought for the identified improvements. The master
plan is predicated upon simplifying and improving the waste
treatment processes, which will favorably impact the
management of chronic toxicity.
Authorizing additional THE work with Aquatic Sciences
Consulting as we continue efforts to both identify and
remediate all sources and causes of chronic toxicity.
As you will recall, I expressed a great deal of frustration at
points in the past with other consultant efforts (including
those of Burlington Research), however, I have for some
time been impressed with the capabilities of Mr. Botts and he
has proven to be a strong partner for us in our ongoing work
with chronic toxicity compliance. Mr. Botts has been present
with us in meetings with you and your Staff over the past
year or so.
Our engagement of Environmental Attorney Glenn Dunn,
with the firm of Poyner & Spruill, in mid September, 1999.
This engagement in my view represents one other example
of our commitment to engage whatever resources
(engineering, legal or otherwise) to be sure we conduct our
activities with respect to our wastewater operations, and any
Special Orders, with the end goal in mind of complete and
consistent compliance with our treatment responsibilities so
as to protect the natural resources of the State. As you
recall, Mr. Dunn was present during our most recent meeting
on September 23'd
While the above list is not by any means all inclusive, I believe it
clearly indicates our "organization wide" commitment (to include my
Office, those that report directly to me and, of course, our City
Council) to operating our Wastewater Treatment systems in full and
complete compliance with all regulatory standards of NCDENR.
H:Vetterslschuster 10-1-99.doc Page 3 of 11

B) Further Responses (to supplement the general observations of the City
Manager) provided by both the City's technical staff and Mr. John Botts,
with Aquatic Sciences Consulting) to DWQ Questions Posed in September
23, 1999 Meeting are as follows:
Question #1: How does recent progress (e.g., last year) compare to earlier
progress?
The City of Henderson (City) made substantial efforts to reduce toxicity and comply with
all NPDES permit limits added since 1990 as evident by the list of accomplishments in
exhibit 11 B of the September 22"d letter to Mr. Ken Schuster.
However, the City realized that our private consultant was generating a lot of lab data
but was not providing the organization with specific goals, on site inspections and
guidance needed to solve our toxicity problems. In addition, the City's pretreatment
program was managed out of the engineering department which reduced the
effectiveness of the program.
As a result, the City made some major changes in the spring of 1998 that has a very
positive impact on our pretreatment and toxicity reduction programs.
Mr. John Botts if Aquatic Sciences Consulting was employed to replace the previous
private contractor. Mr. Botts is well known for his accomplishments in the toxicity
reduction field and he has brought excellent management and organization to our
toxicity reduction program.
The City also transferred the pretreatment program from the Engineering Department to
the wastewater treatment plant and hired a full time pretreatment coordinator to handle
these duties which include toxicity reduction.
These major changes took time for everyone to make adjustments but the results have
been to build a team at the wastewater treatment plant that is becoming more skilled
each day and the guidance of Mr. Botts has brought the needed organization and
knowledge to what has been a very difficult toxicity reduction program to manage
because because of the inability of any lab to be able to identify the toxicant(s) and the
transient complex and variable nature of the toxicity making it hard to locate.
To address this difficult problem, the City committed significant resources to develop a
multi -faceted THE approach. This approach involved (1) toxicity identification
evaluation (TIE) procedures for identifying the effluent toxicant(s), (2) optimization of the
treatment plant to enhance toxicity removal, (3) and expanded pretreatment program,
and (3) toxicity tracking techniques for identifying sources of toxicity, The city's progress
in establishing industrial user requirements for toxicity and added hydrogen peroxide for
toxicity treatment apparently had a positive effect as more than half of the toxicity
compliance tests passed in 1998 (i.e., 5 of 9 tests passed) and only one chronic value
(ChV) was less then 78%.
H:Vetterslschuster 10-1-99.doc Page 4 of 11

Under the direction of the new pretreatment coordinator in 1998 the City (1) instituted
quarterly SIU inspections, (2) updated chemical usage inventories (3) set up a
computerized data base on chemical usage (4) entered chemicals in an aquatox
program to identify potential toxicity problems (5) improved communication and
awareness with industrial customers (6) conducted inspection of new SIUs to search
for toxic discharges (7) refined the technique of the in-house use of microtox to identify
toxic samples within 24 hours with > 90% correlation with cerodaphnia. (8) identified
and eliminated the toxicity from three industrial users (Softspun, Burkart and
Kennametal),
The City considered the chemical usage inventory important enough to hire a temporary
worker for 1,100 hours to speed up getting this system in place.
Due to the intermittent toxicity, the City was forced to develop new procedures for
tracking sources of toxicity in 1999. The new procedures were necessary because
EPA's methods were not adequate for characterizing intermittent toxicity. After six
months of method development, a prototype was successfully used to identify an
intermittent discharger of toxicity (Harriet & Henderson Cotton Mills). The City has
required the discharger to investigate the cause of toxicity at its facility. In 1999, the city
also required a major textile industry, Americal, to conduct a THE after monitoring tests
showed toxicity. Americal attributed the toxicity to a polymer and optimization of
polymer use subsequently appeared to eliminate the toxicity. Confirmatory tests are in
progress.
In summary, since 1997, the city has worked intensively to achieve compliance
with the toxicity limit, but it was the reorganization in 1998 that gave an organized
direction to the THE program. After extensive work to develop new THE
procedures, a source of intermittent toxicity was identified. The City must have
additional time to ensure that toxicity from this last apparent source of toxicity is
eliminated and the effect on the city's discharge can be verified. In the event that
elimination of this source of toxicity does not achieve compliance, the City is
investigating toxicity treatment by activated carbon and an upgraded biological
treatment process. Again, however, time is needed to prove the validity of these
ultimate toxicity control measures.
Question #2: When did Americal start up bleaching test runs? When did
America[ begin actual production of the bleach process?
See attached letter from Americal (marked as Exhibit B-2) as an initial reply to this
question. Special Note: The City's initial review of this information (which may concur
with DWQ review) suggests that further more detailed and definitive information may be
required and should that be the case, further information will be forthcoming ... perhaps
mailed directly to Mr. Tom Poe and Ms. Dana Foley in the Pretreatment Office. WWTP
Director Tom Spain will coordinate additional follow up as needed on this matter.
H.Vetterslschuster 10-1-99.doc Page 5 of 11

Questions #3: Chronic values on a bleach waste stream sample were <1%.
Americal's percent flow contribution is 6.4%. How can you conclude these
results confirm that the bleach process does not contribute to toxicity?
Results of bleach waste stream tests performed in late March and mid April were
reported in Americal's consultant letter dated May 3, 1999 as follows:
"A mock effluent was tested to evaluate the toxicity of the new combined bleach/dye
waste stream. The bleach process sample was a composite of the wash and rinse
cycle wastes collected from a single bleach run (March 22nd). This waste stream was
not treated in the pretreatment facility, therefore, its toxicity is assumed to represent a
worse case [Page 2 - 3'd paragraph].
Results for the combined bleach/dye waste stream sample show greater toxicity
compared to the dye waste stream sample alone (i.e., IC25s of 0.5% vs. 4.7%). It was
difficult to accurately measure both chlorine and H2O2 due to analytical interferences.
Sufficient thiosulfate was added to eliminate chlorine, however, due to the imprecision
of the H2O2 analysis, it was not possible to determine if sufficient thiosulfate was present
to also reduce residual H2O2. Therefore, some of the observed toxicity may have been
related to residual H2O2. Adjustments in the analytical methods were used in follow up
testing of the bleach waste stream [Page 3 - 41h paragraph].
As shown in Table 3, complete mortality was observed in each of the bleach waste
stream samples after 48-hours (i.e., 48-hr LC50 <1 %). No difference in toxicity was
observed between samples containing softeners and the sample with no softener;
therefore, toxicity did not appear to be related to the softeners used in the bleaching
process. Chlorine and H202were eliminated from the samples; however, the excess
thiosulfate added to the samples probably contributed some toxicity. Nonetheless, the
majority of toxicity can not be explained by thiosulfate addition [Page 3 - last paragraph].
The effluent sample collected after optimization of polymer addition exhibited the same
level of toxicity as the bleach waste stream samples (i.e., complete mortality in 48-
hours, IC25 <1 %). This sample was more toxic than the effluent sample collected on
March 22"d - 23'd These results indicate that the polymer is not the primary cause of
toxicity. Americal had increased its bleach waste stream flow between collection of the
effluent samples. The increased bleach waste stream flow, together with the similarity
in toxicity results for the bleach waste stream and effluent samples, suggest that the
bleach waste stream is contributing toxicity [Page 6 - 2"d paragraph].
and in the City's quarterly report dated May 12, 1999 as follows:
"America) optimized its polymer usage by reducing the dosage to one third of previous
levels. An effluent sample (April 15` - 16th) collected after optimization of polymer
usage exhibited the same level of toxicity as the bleach waste stream samples (i.e.,
complete mortality in 48-hours, IC25 <1 %). This sample was more toxic than the
effluent sample collected on March 22"d - 23'd These results indicate that the polymer
is not the primary cause of toxicity.
H.9letterslschuster 10-1-99.doc Page 6 of 11

Americal had increased its bleach waste stream flow between collection of the effluent
samples. The increased bleach waste stream flow, together with the similarity in toxicity
results for the bleach waste stream and effluent samples, suggest that the bleach waste
stream is contributing toxicity [Page 6 - last paragraph and Page 7 - first paragraph]."
As noted above, the bleach waste stream samples were not pretreated; therefore, the
measured toxicity was considered in relation to Americal's other waste stream (dye
process). In the March and April tests, it became apparent that some of the toxicity of
the bleach waste stream sample was due to sodium thiosulfate that was added to
reduce toxic background levels of chlorine and hydrogen peroxide. Although Americal's
consultant concluded that the bleach waste stream was contributing to its discharge
toxicity (see May 3'd report excerpt), subsequent tests performed on May 12'h indicated
that the background chlorine and hydrogen peroxide may present more of an
interference than previously thought. This conclusion is explained in Americal's June 9,
1999 consultant report:
"It was necessary to add sodium thiosulfate to each of the samples because of the
relatively high levels of chlorine and H2O2 in the bleach stream. However, the amount of
thiosulfate needed to completely reduce chlorine and H2O2would have caused toxicity
in even the lowest toxicity test concentrations. Therefore, it was decided to optimize the
thiosulfate dose to try to reduce chlorine and H2O2 to nontoxic levels in the lowest test
concentrations (i.e., 1, 2, and 4%).
Within 24 hours of initiating the tests, complete mortality was observed down to the 4%
concentration in each sample. The 4% test concentrations were reanalyzed for chlorine
and H2O2. Although H2O2 appeared to be reduced at test initiation, residuals of 20 - 25
mg/L were found upon reanalysis. The presence of chlorine in the samples appeared to
interfere with the original H2O2 measurement [Page 2 - last paragraph and continuing]."
"Results of the bleach stream tests are shown in Table 1. As described above, the
repeated tests provide a more accurate indication of the toxicity of the samples. The
results for these tests indicate that all three samples are nearly equally toxic (i.e., IC25 -
0.28 to 0.44%). Although toxic chlorine and H2O2 levels were not detected in the 4%
test concentration, the combination of the reducing agents (i.e., thiosulfate and bisulfite)
and other salts in the bleach stream (i.e., potassium hydroxide and whitener) may have
contributed to the observed toxicity. This background toxicity appears to have masked
the toxicity of VircoWet NSL and Q13.
The background toxicity in the bleach stream samples makes it difficult to interpret the
toxicity results. Therefore, it is not possible to determine if VircoWet NSL and/or Q13
are contributing toxicity to the bleach stream [Page 4 - 2"d and 3`d paragraphs]."
As noted, residual hydrogen peroxide was found in bleach waste stream samples after
addition of sodium thiosulfate. These results cast some doubt on the March and April
tests with respect to the oxidants being "eliminated". Also, the addition of thiosulfate
likely contributed to the observed toxicity.
H:Vetterslschuster 10-1-99.doc Page 7 of 11

In summary, it was difficult to evaluate the bleach stream samples because of the toxic
background levels of chlorine and hydrogen peroxide. Although the oxidants
contributed to toxicity, chlorine and hydrogen peroxide would be reduced when
Americal's discharge mixes with the City sewer flow because of the presence of organic
material that imparts a high oxidant demand.
At the same time the bleach tests were performed, tests conducted on Americal's
discharge showed that toxicity may be related to polymer use in the pretreatment
facility. These results were summarized in Americal's consultant report dated March 15,
1999 and the City's May 12, 1999 quarterly report as follows:
"Although Americal's discharge was toxic, the pretreatment facility influent was not toxic
(i.e., IC25 of 81 vs. 54%, respectively). The difference between these samples is that
the Americal discharge had undergone pretreatment (i.e., addition of caustic, oxidants,
and polymers followed by dissolved air flotation), whereas the Americal influent was not
pretreated. These results suggest that the treatment process is introducing or creating
toxicity. Possible reasons for the observed toxicity are that the treatment additives are
toxic or the treatment oxidants break the dye chemicals down into more toxic treatment
byproducts. Some surfactants such as nonyl phenols are known to breakdown into
toxic byproducts [Page 8 - 15` paragraph of Americal's consultant report and Page 4 -
2"d to last paragraph].
Although Americal reduced polymer use, effluent monitoring did not initially show a
corresponding decrease in toxicity (see above excerpts). However, after further
reduction in polymer use, effluent toxicity decreased as noted in Americal's June 9,
1999 consultant report:
As shown in Table 1, Americal's effluent [collected May 14] was less toxic (ChV = 5.6%)
than the last effluent sample tested (i.e., 48-hr LC50 <1 % for sample collected 15-16
April). Americal reduced the dose of a polymer used for treatment before the last
effluent test, however. Americal believes that residual polymer may still have been in
the treatment system. Residual polymer should have been purged from the treatment
system when the May 12th effluent sample was collected. Nonetheless, it is not known
whether or not the reduced effluent toxicity is related to the decreased polymer use
[Page 3 - 2°d to last paragraph].
Please note that the last sentence of this excerpt was intended to mean that additional
data were needed to confirm the results of the polymer reduction. These results were
confirmed by tests performed on samples collected on June 7, 1999. Americal's test
showed no chronic toxicity at the 8% effluent concentration. Although a test performed
by the City in the same week was a "fail", it was nearly a "pass". A RTA test performed
in July showed no refractory toxicity in an Americal discharge sample.
In summary, the polymer used in the pretreatment plant was determined to be the
primary cause of toxicity, not the bleach waste stream.
H:Vetterslschuster 10-1-99.doc Page 8 of 11

Question #4: Why is it valid to neutralize chlorine and hydrogen peroxide before
testing to confirm the bleach process is or is not toxic?
As noted above, sodium thiosulfate (and sodium bisulfite) was used to reduce oxidants
before testing. It was known that the chlorine and hydrogen peroxide concentrations
would be toxic, however, it was assumed that the oxidants would be reduced when
Americal's discharge mixes with the City sewer flow (i.e., domestic wastewater imparts
a high oxidant demand). Americal's objective was to evaluate the toxicity of other
constituents in the bleach waste stream, particularly the softener and wetting agent. It
was necessary to try to remove the oxidants before characterizing the toxicity of the
other bleach waste stream constituents.
Question #5: Explain conclusions in Section 3.4 in the City's May 12, 1999
quarterly report regarding the comparison of bleach testing to polymer reduction.
As stated in Section 3.4 of the City's quarterly report dated May 12, 1999:
"America) optimized its polymer usage by reducing the dosage to one third of previous
levels. An effluent sample (April 15t - 16th) collected after optimization of polymer
usage exhibited the same level of toxicity as the bleach waste stream samples (i.e.,
complete mortality in 48-hours, IC25 <1 %). This sample was more toxic than the
effluent sample collected on March 22nd - 23`d These results indicate that the polymer
is not the primary cause of toxicity.
Americal had increased its bleach waste stream flow between collection of the effluent
samples. The increased bleach waste stream flow, together with the similarity in toxicity
results for the bleach waste stream and effluent samples, suggest that the bleach waste
stream is contributing toxicity [Page 6 - last paragraph and Page 7 - first paragraph]."
Although Americal reduced polymer use, effluent monitoring did not initially show a
corresponding decrease in toxicity. However, after further reduction in polymer use,
effluent toxicity decreased as noted in Americal's June 9, 1999 consultant report:
As shown in Table 1, Americal's effluent [collected May 14] was less toxic (ChV = 5.6%)
than the last effluent sample tested (i.e., 48-hr LC50 <1 % for sample collected 15-16
April). Americal reduced the dose of a polymer used for treatment before the last
effluent test; however, Americal believes that residual polymer may still have been in
the treatment system. Residual polymer should have been purged from the treatment
system when the May 12'h effluent sample was collected. Nonetheless, it is not known
whether or not the reduced effluent toxicity is related to the decreased polymer use
[Page 3 - 2nd to last paragraph].
Please note that the last sentence of this excerpt was intended to mean that additional
data were needed to confirm the results of the polymer reduction. These results were
confirmed by tests performed on samples collected on June 7, 1999. Americal's test
showed no chronic toxicity at the 8% effluent concentration. Although a test performed
by the City in the same week was a "fail", it was nearly a "pass". A RTA test performed
in July showed no refractory toxicity in an Americal discharge sample.
H:Vetterslschuster 10-1-99.doc Page 9 of 11

Question #6: Was the September 1998 toxicity test of Americal's discharge valid
or not? When was it determined to be invalid? Why is it invalid?
Americal passed the quarterly monitoring test performed in the third quarter of 1998
(August). A test performed as part of a refractory toxicity assessment (RTA) in
September was invalid due to control problems in the toxicity test. Information in this
regard is reported in a letter/test reports, dated 10-27-98, from EA Engineering, Science
and Technology, from Ms. Virginia A. Sohn to VWVfP Director Tom Spain (marked as
Exhibit B-6). As noted in this Exhibit, the laboratory attempted to pool the control
results for all four toxicity tests performed during the period. However, it is not valid to
pool control data for tests that were initiated on different days using a different brood of
organisms. The Americal test was determined to be invalid shortly following receipt of
the laboratory report (early November). Unfortunately, this information was not
interpreted in time for the preparation of the city's quarterly progress report, which was
submitted on November 12, 1999. The quarterly report incorrectly indicated that the
test was a failure.
In August 1998, Americal had requested an increase in flow and the city responded by
requiring Americal to pass a toxicity test at the higher flow concentration (along with
other requirements). Therefore, Americal performed a toxicity test in October for the
purpose of determining if the discharge would be toxic at an increased flow of 8%. It is
important to note that Americal's test was not performed as a follow-up to the invalid test
performed by the city in September.
The city received Americal's October test results in late October. Based on concern
about this failure at the higher flow value, the cit� attempted to test Americal discharge
samples collected in November (Nov 2nd and 16 h). However, Microtox results indicated
relatively low toxicity (i.e., ChV of 70.7% and >100%, respectively), therefore, the
samples were not tested for toxicity to Cenodaphnia dubia. A follow-up sample
collected in December confirmed toxicity in Americal's discharge. As required in the
industrial user permit (IUP), Americal performed a RTA test to determine if toxicity
would be expected to pass through the city's treatment plant. Refractory toxicity was
observed, therefore, Americal was required to initiate a THE in February.
It is important to note that the city tested Americal's discharge in each quarter of 1998
as required in the industrial user permit (IUP). As noted, additional tests were
performed during the year (i.e., September Cenodaphnia dubia test and November
Microtox tests).
H:Vetterslschuster 10-1-99.doc Page 10 of 11

In conclusion, I trust this follow up information is consistent with what we
understood was needed following our meeting on September 23`d. Following the
reviews by you and your Staff, please contact us if additional information is
required.
Also, please be mindful of our request to meet with you again (and you indicated
you may others present, which is certainly fine with us) prior to the final and
definitive decision regarding our extension request, which we understand will
likely be made some time toward mid to late October.
Thank you for your continuing assistance and guidance in this matter. With my best
regards, I am
EMW/dew
Attachments — Exhibits B-2 and B-6
Mr.
Tom Poe, Pretreatment
)
Ms.
Dana Foley, Pretreatment
Mr.
Kevin Bowden, DWQ
Mr.
Ted Cashion, DWQ
Mr.
Kirk Stafford, DWQ
)
Ms.
Judy Garrett, DQW
)
Sincerely,
CITY OF HENDERSON
TM. illia s
City Manager
Ms. Owens: Again, since I'm unsure
where these individuals
officers are, would you be
so kind as to forward each
of them a duplicate of this
letter and the referenced
Exhibits (sufficient copies
are attached). Thanks
EMW /
Mr. Mark Warren, Asst. Manager
Mr. Tom Spain, WWTP Director (via fax) *
Mr. Reggie Hicks, Pretreatment Coordinator (via fax)
Mr. H. Glenn Dunn, Esq., Poyner & Spruill (via fax: [phone])
Mr. John A. Botts, Aquatic Sciences Consulting (via fax: [phone])
* faxed copy only — original will not follow
H:Vetterslschuster 10-1-99.doc Page 11 of 11

01/26/1994 21:28 2524923:- HENDERSON WWTP PAGE 01
AMERICHL
C o r: e O R A 7 i p N
Septennber3o, 199g
Mr. Tom Spain
Waste Water Treatment Plant
P.D. Box 1334
Henderson, NC 27(5536
Dear Tom:
This latter Is in answ ar to your inquiry as to when we began bleaching socks. We have
been bleaching cotton hosiery as part of our product mix for at least 20 years. Over the
Past few years our produce mix has gradually shifted to more cotton products and less
dyed nylon products.
Early this year we replaoed soma of our nylon knitting equipment with sock knitting
equiPrnsnt. Start up of this equipment beginning in late February has resulted in a
gradual change in our dyeingfblseching mbc Full production on this equipment was
reacted about mid May to early June.
We continue to pledge our ifull cooperation to the city with regard to fhtaing and solving
its waste water to)dcity Problems.
BPI E. Bailey
Exe. V P. Operations
0
CC: Reggie Hicks
Ic%XI IATjr — Q - z
319 l�merrrol e.,d oir,,. sc. .s�v n�nd�rsop MC 27536 • [phone]
19-91-99 99:36 TO:CITY OF HENDERSON FROM:2524923324 P91

EA Engineering, Science, and i 11ogy
27 October 1998
Mr. Tom Spain
City of Henderson
Nutbush Creek WWTP
Highway 39 North
Henderson, NC 27536
Dear Mr. Spain:
15 Loveton Circle
Sparks, MO 21152
Telephone: [phone]
Fax: [phone]
Enclosed please fmd two copies of EA Engineering, Science and Technology's final report
titled "Results of Limited Scale Chronic Toxicity Testing with Ceriodaphnia dubia on Samples
from the City of Henderson's Nutbush Creek WWTP" (Report # 2926).
Should you have any questions or comments regarding this report, please do not hesitate to
contact me at [phone].
cc Bill Goodfellow
John Botts
F:\7000310\HENDRSON\LETrERS\2926.
Sincerely,
Virginia A. Sohn
Scientist
Environmental Toxicology
I�DI-r- v - G,

TABLE 3 RESULTS OF LIMITED -SCALE CHRONIC TOXICITY TESTS PERFORMED ON SAMPLES FROM THE CITY
OF HENDERSON, NUTBUSH CREEK WWTP
Sample Description:
Americal
Burkart
EA Accession No:
AT8-596
AT8-595
Test Number:
TN-98-463
TN-98-462
Test Initiation:
1550,
23 September 1998
1215,
24 September 1998
Test Termination:
1702,
30 September 1998
1200,
30 September 1998
Test Concentrations
Survival
Mean Young per
Test Concentrations
Survival
Mean Young per
(percent effluent)
(percent)
Exposed female (t D)
(percent effluent)
(percent)
Exposed female (±S D.)
Control
90l'I
16.8 (t 5.7)lbl
Control
100
21.0 (f 5.1)
0.9
80
25.0 (f 3.7)
0.44
80
18.8 (t 5.1)
1.8
80
23.8 (t 1.3)
0.88
100
19.8 (f 2.5)
3.6
100
19.8 (f 5.7)
1.75
100
19.8 (t 2.0)
7.2
401b1
12.6 (t 11.6)(`)
3.5
100
12.8 (t 6.1)Ibl
14.4
401b>
5.2 (f 7.2)(°)
7.0
80
12.4 (t 8.2)lbl
NOEC:
3.6
NOEC:
1.75
LOEC:
7.2
LOEC:
3.5
ChV:
5.1
ChV:
2.47
IC25:
6.2 (NC)
IC25:
2.7 (NC)
(a) For purposes of statistical analyses, the values used for control survival and reproduction for the Americal test were the mean of the survival and reproduction for all
four controls from this suite of tests (Table 3). Control survival for the specific Americal lest was 60 percent. it
(b) Statistically different (P=0.05) from control indicating an adverse effect on reproduction.
(c) Treatments which have no surviving organisms or have significant mortality are not statistically analyzed for survival or reproduction, per EPA guidelines.
(d) Values in parentheses represent 95 percent confidence limits.
NC = Not calculable

TABLE 3 (Continued)
Sample Description:
Aeration Tank Influent
Effluent before Peroxide
EA Accession No:
AT8-606
AT8-611, 629
Test Number:
TN-98-471
TN-98-476
Test Initiation:
1445, 24 September 1998
1233, 25 September 1998
Test Termination:
1415, 1 October 1998
1200, 1 October 1998
Test Concentrations
Survival Mean Young per
Test Concentrations
Survival Mean Young per
(percent effluent)
(percent) Exposed female (t .D.)
(percent effluent)(percent
dosed female (±SX
Control
100 15.2 (f 2.5)
Control
100 19.2 (f 1.1)
15
100 18.2 (f 6.8)
15
100 19.4 (f 1.1)
30
100 23.8 (t 4.1)
30
100 22.0 (t 2.1)
45
100 22.6 (t 2.3)
45
100 22.4 (t 1.7)
67.5
60 19.8 (t 3.7)
67.5
01°I 11.2 (t 5.4)t`t
90
01°t 01°I
90
01`I 4.4 (f 4.9)I°I
NOEC:
67.5
NOEC:
45
LOEC:
90
LOEC:
67.5
ChV:
77.9
ChV:
55.1
IC25:
73.0 (68.2 - 73.2)Idl
IC25:
57.2 (52.0 - 71.2)Idi
(b) Statistically different (P=0.05) from control indicating an adverse effect on reproduction.
(c) Treatments which have no surviving organisms or have significant mortality are not statistically analyzed for survival or reproduction, per EPA guidelines
(d) Values in parentheses represent 95 percent confidence limits.

CITY OF HENDERSON
Post Office Box 1434
180 Beckford Drive NUIBM OM WASTEWATER
Henderson, North'Carolina 27536-1434 7RFATKENTPLANf
Phone: [phone] FAX: [phone]
Mr, Ken Schuster
Raleigh Regional Supervisor
NC DENR DWQ
1628 Mail Service Center
Raleigh, NC 27699-1628
Re: City of Henderson Nutbush Creek W WTP
NPDES #NC0020559
SOC-EMC WQ No. 96-05
August Quarterly THE Report
Dear Mr. Schuster,
August 10, 1999
DENNR RALEIG:
I am forwarding our August Quarterly Toxicity Reduction Evaluation (TRE) report as
required by our SOC.
Please note that the THE work with Americal is covered in detail and hopefully will clear
up any questions that were brought up during our meeting on July 27, 1999.
If you have any question please contact me at 252-431-6081.
Sincerely,
M'
r-->
Thomas M. Spain
WWTP Director
C: Eric Williams, City Manager
Mark Warren, ACM
Reggie Hicks, Lab Supervisor
Judy Garrett, DWQ-RRO
Kirk Stafford, DWQ-RRO
Matt Matthews, DWQ-ATU
Kevin Bowden, DWQ-ATU
Tom Poe, DWQ, Pretreatment
Dana Folley, DWQ, Pretreatment
John Botts, Aquatic Sciences Consulting

Mr. Ken Schuster
Regional Supervisor
Raleigh Regional Office
Department of Environment
and Natural Resources
1628 Mail Service Center
Raleigh, North Carolina 27699-1628
RE: Follow Up From Our July 27th Meeting
Special Order By Consent EMC WQ No. 96-05
Chronology Of Toxicity Issues—Americal Corporation
Dear Mr. Schuster:
August 4th, 1999
Q
In response to questions raised during our meeting about the chronology of events
involving Americal Corporation, I am forwarding the following items:
1. Chronology outline of toxicity work at Americal since February,1998 to the
present.
2. A copy of Americal's pretreatment permit which lists the toxicity monitoring
requirements for toxicity.
3. A copy of Americal's notification to the City that they would be adding a
bleaching process to their operation.
It was certainly the City's intention to comply with all SOC and Pretreatment
regulations. Recent conversations between my Lab Supervisor/ Pretreatment
Coordinator, Reggie Flicks, and Dana Folley of the State Pretreatment Section
indicated that Americal and we were in monitoring compliance with toxicity.
A detailed quarterly report on our most recent toxicity issues will be submitted by
the August 15th deadline specified in the SOC.
If you need additional information please contact me at 252-431-6081.
C: Eric Williams, City Mgr.
Mark Warren, ACM
Reggie Flicks, Lab Sup.
Judy Garrett, Ral. Reg. Off.
Kirk Stafford, Ral. Reg. Off.
Matt Matthews, Aqua. Tox.
Kevin Bowden, Aqua. Tox.
Tom Poe, Pretreatment
Dana Folley, Pretreatment
Sin rely,
Thomas M. Sm
W WTP Director

Chronology of Toxicity at Americal
1998 February Test (2/3) Invalid - Control problems
Test(2/10)
Pass
June
Test(6/8)
Pass
August
Test(8/4)
Pass
September
Test (9/22)
Invalid
Control mortality is high. Although control
results for other tests on that date are
pooled; the test is considered invalid.
October
Americal retains an engineering consultant, Leonard Stogner
Test (10/5)
Fail at proposed discharge flow of 8%
Not possible to judge compliance at current
flow (6.4%).
December Test (12/8) Fail
RTA Invalid City performs RTA
(WWfP influent used for control)
Control mortality is high; therefore,
the test is considered invalid.
Report - Americal submits plan for an additional RTA and
preliminary tests of five most used chemicals
1999 January Americal retains John Botts to evaluate causes and sources
of toxicity.
RTA Fail Americal performs RTA
("mock" influent used for control)
- Report - Americal submits report of RTA results and -
chemical tests. Includes plan for additional tests.
THE Date Log - Americal begins to submit weekly chemical usage
reports.
February Report - Americal submits report of chemical review and list
of chemicals to be tested.
RTA Fail Americal performs RTA
("mock" influent used for control)
March Report - Americal submits report of RTA results and a plan for

M
May
June
July
further testing.
Notification (3/17) - Americal reports bleach process change.
Report -
Americal submits plan for evaluating toxicity
reduction by hydrogen peroxide addition.
Test(3/23)
Pass
Test (3/23)
Hydrogen peroxide fails to reduce toxicity.
Test of bleach stream shows toxicity.
Process Change
- Americal reduces polymer usage by 1/3.
Test (4/15)
Americal evaluates toxicity of softeners in bleach
stream. Wetting agent indicated as toxicant.
Limited TIE also shows nonpolar organic toxicants.
Test(4/16)
Fail Slightly toxic because of reproduction.
Report -
Americal submits report of hydrogen peroxide and
bleach stream softener test results. Includes plan
for additional tests.
Test (5/12) Americal evaluates toxicity of wetting agent and
catalyst used in bleaching process. Results are
inconclusive because of background chlorine and
hydrogen peroxide in bleach stream.
Process Change - Americal reduce polymer usage further (30%)
and substitutes wetting agent.
Report - Americal submits report of bleach stream test results.
Test(6/7) Pass Americal performs one sample test.
Test(6/7) Fail City performs two sample test -
(slightly toxic because of reproduction)
Americal submits effluent test results.
RTA Results pending.

DEPARTMENT OF PUBLIC UTILITIES
NUTBUSH CREEK WASTEWATER TREATMENT PLANT
Henderson, North Carolina
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
SEWER USE ORDINANCE OF THE CITY OF HENDERSON
Pursuant to the City of Henderson Sewer Use Ordinance (hereinafter
referred to as "The Ordinance"), and North Carolina General Statue
143-215.1, other lawful standards and regulations promulgated and
adopted by the Department of Public Utilities of the City of
Henderson and the North Carolina Environmental Management
Commission, as amended, and pursuant to the Permit application,
(Hereinafter referred to as "The Application") heretofore filed
with the Department of Public Utilities of the City of Henderson;
"Americal Corporation, P.O. Box 1419, 361 Americal Road, Henderson,
ter referred as "permittee") is
riz
1. Discharge wastewater from said facility classified by SIC
No. 2251 , Permit No. 0001 located at US 1 Bypass,
Henderson, NC into the sanitary sewers of the City of
Henderson Nutbush Creek Wastewater Treatment Plant NPDES No.
DIC0020559 (hereinafter referred to as "the City") in
accordance with effluent limitations, monitoring requirements,
and other conditions contained herein. All such discharges
shall be made at discharge locations approved in advance by
the Public Utilities Department.
2. Continue operation of existing pretreatment facility,
consisting of a bar screen, flow equalization with aeration,
chemical reaction tanks, DAF unit, Sludge Handling Equipment.
3. after receiving authorization to construct from the City
of Henderson, construct and operate additional pretreatment
_ units as needed to meet the final effluent limitation from
facility classified by SIC No. 2251
This permit shall become effective November 10 , 1997
This permit and the authorization to discharge shall expire at
midnight on July 21, 2001
Signed this the day of Nol--1 id , 1�" f
Ci of Henderson
�Hea son, North Carolina
Eri ` liams
ty M nager

NAME: AMERICAL CORPORATION IU PERMIT NO. 0001
PART 1. (A) DESCRIPTION OF DISCHARGES
PIPE
001 - Discharge of domestic wastewater only.
002 - Discharge of wastewater generated by dyeing process.
SHANK STREET
I
CITY SE':IEn LINE
AMERICAL. INC. - — — — - 001
DOMESTIC
LIME
EOUA.
PR0CEs LONE. 0151N I
1
METEARIC
I.I;.f:11:,LE
4 • /�J
OU1FALL /
002
NOT _' SCALE

(B). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS:
Effective November 10, 1997 and lasting until the expiration date
of this permit, the permittee is authorized to discharge from Pipe
002. This discharge shall be limited and monitored as specified
below. Parameters and prohibitions not included below shall be
regulated and limited in compliance with the City of Henderson
Sewer Use Ordinance.
PARAMETER
SURCHARGE
LIMITS
MONTHLY
AVERAGE
(MG/L)
DAILY MAX
LBS/DAY
SAMPLE
TYPE
FREQUENCY
BY CITY
SAMPLE
LOCATION
FLOW
.160 M.GD
RECORD
DAILY*
002
BOD5
300
500.0
667.20
COMP
MONTHLY
002
TSS
170
250
333.60
COMP
MONTHLY
CO2
COD
600
900.0
1200.96
COMP
MONTHLY
002
TKN
35.0
40.0
53.37
COMP
MONTHLY
002
CHROMIUM(CR)
.08
.107
COMP
MONTHLY
002
CADMIUM(CD)
.002
.0027
COMP
MONTHLY
002
^.OPPER(CU)
.07
.093
COMP
QUARTERLY
002
AD
.026
.035
COMP I
MONTHLY
002
ZINC
.50
.667
COMP
QUARTERLY
002
II OIL & GREASE I 175.0 187.15 I GRAB I QUARTERLY 1002 jII
PHOSPHOROUS I 1 8.0 10.67 COMP I MONTHLY 002 I
MBAs I MONITORING ONLY I COMP I QUARTERLY 1002
CHLORIDES I MONITORING ONLY I COMP I SEMI-ANNUAL 1 002
*Daily Flows shall be recorded at the pretreatment facility on a log farce and maintained for review by City.
(B1). CHRONIC_ TOXICITY MONITORING AND SPECIAL CONDITIONS -
Effluent from Pipe 002 shall be monitored quarterly by the City
using a modified ceriodaphnia chronic toxicity method (DEHNR 1991)
and the Microtox Chronic Toxicity test (Microbics 1994). These
tests will include at least one sample concentration that is equal
to the maximum percent flow contribution of the discharge to the
Nutbush Creek WWTP as defined by the City when the test is
performed.
If the Ceriodaphnia test result shows chronic toxicity (failure) at
the maximum percent flow contribution, Americal unless otherwise
notified by the City will perform a follow up toxicity test within
the next calendar month using a modification of EPA's refractory
toxicity assessment (RTA) procedure (1997). This test will involve
treatment of the discharge sample in a bench -scale simulation of
the Nutbush Creek WWTP and subsequent toxicity measurement. The

RTA test will estimate the "refractory" toxicity of the discharge,
which is the toxicity that would be expected to pass through the
Nutbush Creek WWTP and contribute to effluent toxicity. All test
results shall be sent to the WWTP Director no later than 10 days
after receiving the results.
Unacceptable RTA toxicity is defined as a significant percent
difference between the chronic inhibition concentration (IC 25)
values for the discharge - spiked test simulation and the control
simulation as determined by a comparison of the 95 percent
confidence limits. If the RTA results show unacceptable toxicity,
the following limitations and requirements shall become effective:
(1) A toxicity reduction evaluation (TRE) to identify the causes
and sources of chronic refractory toxicity shall be performed
by the industry. The industry may do this in-house or with a
consultant. The TRE shall begin within 30 days of receiving
the RTA results showing unacceptable toxicity and a report on
the TRE shall be submitted to the WWTP Director within six
months of initiating the TRE. The TRE Report shall identify
measures to reduce toxicity and shall include a schedule for
implementation of the control measures. In addition, monthly
progress reports shall be sent no later than 15 days past the
last date of the previous month.
(2) After implementation of the selected toxicity reduction
method, toxicity monitoring using the RTA procedure shall
continue on a monthly basis by the industry until results of
two consecutive monthly tests show no unacceptable chronic
refractory toxicity(as defined above). Once this condition is
met, the frequency of monitoring with the RTA procedure will
be reduced to quarterly testing. After a year of quarterly
monitoring or RTA tests that show no chronic toxicity at the
percentage flow contribution, semi-annual monitoring will be
performed.
The City reserves the right to increase or decrease this
— monitoring requirement.
(3) TRE date logs, Chemical usage fact sheets, chemical
stewardship data, shall be submitted to the WWTP Director
monthly with a copy going to the City's designated consultant.
The date logs shall be in a format approved by the City and
shall be sent in no later than the 15 days after the end of
the preceding month. Failure to send the date log within the
deadline date shall result in a Notice of Violation. The
second violation shall result in a city penalty of not less
than $50.00 per violation. Each day of non -receipt of
information shall constitute a violation.
(C) Effluent entering the City's sewers at each discharge point
shall be sampled by an automatic sewage sampling device with
refrigerated sample retention as approved by the City.
Effluent that cannot be sampled by an automatic sampling
device, shall be sampled by an approved method referenced in
the analytical requirements of 40 CFR 136. Sampling devices
a

shall be as approved by the City, installed at permittee's
expense and operated and maintained by the Permittee. Samples
shall be collected as delineated in the Permit. Samples shall
be taken on consecutive days. The city shall have access to
pull samples from the permittee's sampling devices.
(D) Permittee's discharge pH shall not be less than 6.0 standard
units nor greater than 10.0 standard units and shall be
monitored by grab sample.
(E) Permittee's discharge temperature shall not be greater than 65
degrees C.
(F) Should voluntary or required split sampling be taken, -the
above tests shall be sent to the City of Henderson, 180
Beckford Drive, P.O. Box 1434, *Henderson, NC 27536. The
results shall be sent to the City no later than the last day
of the month following the previous monthly sampling. If no
discharge occurs during the reporting period, "No Discharge"
shall be reported.
(2) DEFINITIONS:
(a) The "monthly average" discharge means permittee's total
effluent discharge into the City sewers during a calendar
month, divided by the number of days in such month during
which permittee actually discharged effluent in to the City's
sewers. In the event that less than daily sampling is
required by this permit; the daily average discharge shall be
determined by the summation of all the measured daily
discharges divided by the number of days :sampled during the
calendar month when the measurements were made.
(b) A "grab sample" for monitoring requirements, is defined
as a single "dip and take" sample collected at a
representative point in the discharge stream. _'
(c) A "composite sample" consist of grab samples collected at
equal intervals.and combined proportional to flow, a sample
continuously collected proportionally to flow, or equal
volumes taken at varying time intervals. If a composite
sample is obtained from grab samples, the following
requirements apply. Intervals between effluent grab samples
shall be no greater than hourly except where detention time of
the wastewater in the facility is greater than 24 hours, in
which case, the interval between grab samples shall be of no
greater in number of hours than the detention time in number
of days; provided however, in no case may the time between
effluent grab samples be greater than six hours nor the number
of grab samples less than four during any discharge period of
24 hours or less.
(d) An "instantaneous" measurement, for monitoring
requirements, is defined as single reading, observation, or
5

measurement.
(e) DWQ means the Division of Water Quality of the Department
Of Environment, Health, and Natural Resources, of the State of
North Carolina.

(3) MONITORING AND REPORTING:
(a) Representative Sampling by Citv and SIU.
Samples and measurements taken as required herein shall be
representative of the volume and nature of the monitored
discharge. All samples shall be taken at the monitoring
points specified in this permit and unless otherwise
specified, before the effluent joins or is diluted by any
other waste stream, body of water, or substance. Monitoring
points shall not be changed without notification to and
approval by the Permit issuing authority.
(b) Reporting by City.
Monitoring results obtained by the City shall be checked for
compliance with the permit and any violations that occurred
shall be reported to the permittee by the City.
(c) Test Procedure
Test procedures for the analysis of pollutants shall be
performed in accordance with the techniques prescribed in 40
CFR Part 136 and Amendments thereto unless specified otherwise
in the monitoring conditions of this permit.
(d) Recording Results.
For each measurement or sample taken pursuant to the
requirements of this permit, the Permittee shall record the
following information:
i. The exact place, date, time of sampling.
ii. The dates the analyses were performed.
-- iii. The person(s) who performed the analyses;
iv. The analytical techniques or methods used; and
V. The results of all required analyses.
(e) Additional Monitoring by permittee.
If the permittee monitors any pollutant at the location(s)
designated herein, the results of such monitoring shall be
included in summary form as set forth in Section 32 Part (g).
Such increased monitoring frequency shall also be indicated.
The City may on a more frequent basis monitor other pollutants
not required in this permit.
(f) Records Retention.
All records and information resulting from the monitoring
activities required by this permit including all records of

analyses performed and calibration and maintenance of
instrumentation and recordings from continuous monitoring
instrumentation shall be retained by the Permittee for a
minimum of three (3) years, or longer if requested in writing
by the City. When informing the Nutbush Plant, the WWTP
Director or the Chief Plant Operator shall be notified.
(g) Reporting by SIU.
Monitoring results obtained by the permittee shall be
summarized and postmarked no later than the last day of the
month following the month in which the samples were taken.
Copies of these and all other reports required herein shall be
submitted to the permit issuing authority at the following
address:
City of Henderson
P.O. Box 1434
Henderson, NC 27536
(h) Resampling if violation.
If the sampling performed by the permittee indicates a
violation the permittee shall notify the City of Henderson
within 24 hours of becoming aware of the violation the
permittee shall also repeat the sampling and analysis and
submit the results to the City within 30 days after becoming
aware of the violation.
(i) Flow measurement method - Pipe 01. Continue usage of
existing continuous recording totalizing flow meter capable of
measuring flows with a maximum deviation of less than 10% from
true discharge rates throughout the range of expected
discharge volumes. Modifications to the flow metering
equipment shall be approved by the City of Henderson prior to
installation.
(j) Calibration of flow measurement devices.
The permittee shall calibrate and maintain all flow
measurement devices to ensure that the accuracy of the
measurements is consistent with the accepted capability of
that type of device. Calibration shall be performed a minimum
of once per year and a copy of the certification shall be sent
to the Pretreatment Coordinator.
4. OPERATIONAL REQUIREMENTS:
(a) Change in Discharge.
All permittee's discharges and the operation of its facilities
shall be in compliance with the terms and conditions of this
permit and the Sewer Use Ordinance. The discharge of any
pollutant identified in this permit more frequently than or at
a level in excess of that authorized shall constitute a
violation of the permit and the Ordinance. Any anticipated
facility expansions, production increases, or process

modifications which will result in new, different, or
increased discharges of pollutants must be reported by
submission of a new permit application or, if such changes
will not violate the effluent limitations specified in this
permit, by written notice to the City of such changes.
Following such notice, the permit may be modified to specify
and limit any pollutants not previously limited.
(b) Noncompliance Notification.
If, for any reason, the permittee does not comply with or will
be unable to comply with any effluent limitation specified in
this permit or any other act or requirement of this permit,
the permittee shall provide the City with the following
information, in writing, within five(5) days of becoming aware
of such condition:
i. A description of the discharge or other non -complying
act and cause of non-compliance; and
ii. The period of noncompliance, including exact dates
and times, or if not corrected, the anticipated time the
noncompliance is expected to continue, and steps being
taken to reduce, eliminate, and prevent recurrence of the
noncomplying discharge.
In no event, however, shall continued noncompliance of whatever
duration, or notice of noncompliance, or any extension of time or
other indulgence granted by the City with respect to the same be
deemed a waiver by the City and permittee shall, at all time of
noncompliance, remain subject to the procedures prescribed in the
event of noncompliance outlined in Section 7 hereof and in the
Ordinance.
(c) Facilities Operation.
The permittee shall be at all times maintain in good working
order and operate as efficiently as possible all treatment or
control facilities or systems installed or used by the
permittee to achieve compliance with the terms and conditions
of this permit and the Ordinance. The bypass of treatment
facilities is prohibited except as provided for and in
accordance with the requirements set forth by this permit.
(d) Upset Conditions.
An "upset" means an exceptional incident in which there is an
unintentional and temporary noncompliance with the effluent
limitations of this permit because of factors beyond the
reasonable control of the permittee. An upset does not
include noncompliance to the extent caused by operational
error, improperly designed or inadequate treatment facilities,
lack of preventative maintenance, or careless or improper
operations. An upset may constitute an affirmative defense
for action brought for the noncompliance. The permittee has
the burden of proof to provide evidence and demonstrate that
0

none of the factors specifically listed above were responsible
for the noncompliance.
(e) Prevention of Adverse Impact.
The permittee shall take reasonable steps to minimize or
prevent any discharge in violation of this permit which has a
reasonable likelihood of adversely affecting human health, the
POTW, the water receiving the POTW's discharge, or the
environment.
(f) Accidental Discharges.
The permittee shall provide protection from accidental
discharges of prohibited materials or other substances
regulated by this permit. If the permittee experiences an
accidental discharge they shall inform the Nutbush Creek
Wastewater Treatment Plant immediately upon the first
awareness of the commencement of the Discharge. A written
follow-up report shall be filed by the permittee within five
(5) days. When informing the Nutbush Plant, the WWTP Director
or the Chief Plant Operator shall be notified.
(g) Bvoassing.
Any diversion from, or bypass of, facilities necessary to
maintain compliance with the terms and conditions is
prohibited, except (i) where temporarily unavoidable to
prevent loss of life or severe property damage, or (ii) where
temporary excessive storm drainage or runoff would damage any
facilities necessary for compliance with the effluent
limitations and prohibitions of this permit. The permittee
shall promptly notify the City in writing of each such
diversion or bypass and shall, as soon as possible, restore
the facility to normal operation.
(h) Removed substance.
Solids, sludges, filter backwash or other pollutants, removed
in the course of treatment or control of wastewater shall
disposed of an approved manner such as to prevent any
pollutant from such materials from damaging the sewers or
lowering the treatment efficiency of the wastewater treatment
plant. The permittee is responsible for assuring its
compliance with any requirements regarding the generation,
treatment, storage, and/or disposal of "Hazardous Waste", as
defined under the Federal Resource Conservation and Recovery
Act.
(i) Power Failures.
In order to maintain compliance with the effluent limitations
and prohibitions of this permit, the permittee shall either:
In

i. in accordance with the Schedule of Compliance contained in
Section 2 hereof, provide an alternative power source
sufficient to operate the wastewater control facilities, or if
such alternative power source is not in existences or no date
for its implementation appears in Section. 2;
ii. halt, reduce or otherwise control production and/or all
discharges from wastewater control facilities upon the
reduction, loss, or failure of the primary source of power to
said wastewater control facilities. The permittee shall
provide protection from accidental discharges of prohibited
materials or other substances regulated by this permit.
Within (5) days following an accidental discharge the
permittee shall submit to the Wastewater Treatment Plant a
detailed written report describing the cause of the discharge
and measures to prevent similar future occurrences. Such a
notification shall not relieve the permittee from any
liability which hay have incurred as a result of the
discharge.
(j) Duty to comply.
The permittee must comply with all conditions of this permit.
Any permit noncompliance constitutes a violation of the City
of Henderson Sewer Use Ordinance and is grounds for possible
enforcement action.
(5) RESPONSIBILITIES:
(A) Duty To Provide Information.
The permittee shall furnish to the City Manager or his
designee, within a reasonable time, any information which the
Manager, his designee, or the Division of Environmental Management
may request to determine whether cause exists for modifying,
revoking, and reissuing, or terminating this permit or to determine
compliance with this permit. The permittee shall aldo furnish,
upon request, copies of records required to be kept by this permit.
(b) The permittee shall allow the City and/or its authorized
representatives, upon the presentations of credentials:
i. To enter upon the permittee's premises where an effluent
source is located in which any records are required to be kept
under the terms and conditions of this permit; and
ii. At reasonable times to have access to and copy any
records required to be kept under the terms and conditions of
this permit; to inspect any monitoring equipment or monitoring
method required in this Permit; and to sample any discharge of
pollutants.

(c) Transfer of Ownership or Control.
This permit is personal to permittee and is not transferable
or assignable. In the event of any change in. control or
ownership of facilities from which the authorized discharge
emanates or is contemplated, the permittee shall notify the
prospective owner or controller by letter of the existence of
this permit and of the need to obtain a permit in the name of
the prospective owner. A copy of the letter shall be
forwarded to the City.
(d) Availability of Reports.
The permittee shall retain records of all monitoring
information, including all calibration and maintenance records
as well as copies of reports and information used to complete
the application for this permit at least three years. All
records that pertain to matters that are subject to any type
of enforcement action shall be retained and preserved by the
permittee until all enforcement activities have concluded and
all periods of limitations with respect to any and all appeals
have expired.
Except for data determined to be confidential under N.C.G.S.
Section 143-215 (a) (2), all reports prepared in accordance
with the terms shall be available for public inspection at the
Offices of the Pretreatment Coordinator. Effluent data shall
not be considered confidential. Knowingly making any false
statement on any such report may result in the imposition of
criminal penalties as provided in N.C.G.S. Section 143-215.6
(b) (2)•
(e) Toxic Reopener.
If a toxic effluent standard or prohibition (including any
_ schedule of compliance specified in such effluent standard or
prohibition) is established under the Ordinance-lor a toxic
pollutant which is more stringent than any limitation for such
pollutant in this permit, this permit may be revised or
modified in accordance with the toxic effluent standards or
prohibition and the permittee so notified. This permit shall
be modified, or alternatively, revoked and reissued, with new
or modified pollutant limits based upon the Determination of
Pollutants contributing to effluent toxicity.
(f) Oil and Hazardous Substance Liability.
Nothing in this permit shall be construed to preclude the
institution of any legal action or relieve the permittee from
any responsibilities, liabilities, or penalties, to which the
permittee is or may be subject under N.C.G.S. Section 143-215.
75 et. seq. or the Ordinance.
11

(g) Property Rights.
The issuance of this permit does not convey any property
rights on either real or personal property, or any exclusive
privileges, nor does it authorize any injury to private
property or any invasion of personal rights,nor any
infringement of federal, State or local laws or regulations.
(h) Severability.
The provisions of this permit are severable and, if any
provision of this permit, or the application of any provision
of this permit to any circumstance is held invalid, the
application of such provision to other circumstances, -and -the
remainder of this permit shall not be affected thereby.
(i) Civil and Criminal Liability.
Nothing in this permit shall be construed to preclude the
institution of any legal action or relieve the permittee from
any responsibilities, liabilities, or penalties established
pursuant to any applicable Federal and/or State Law or
Regulations.
(j) Federal and/or State
Nothing in this permit shall be construed to preclude the
institution of any legal action or relieve the permittee from
an responsibility, liabilities, or penalties established
pursuant to any applicable Federal and/or Sate law or
Regulation.
(k)
Penalties.
The City of Henderson Sewer Use Ordinance provides that any
person who violates a permit condition is subject,to a civil
penalty up to $10,000 dollars. Each and every day on which a
violation occurs or continues shall be deemed a separate and
distinct offense.
The Sewer Use Ordinance also provides that any person who
knowingly makes any false statement, representation, or
certification in any record or other document submitted or
required to be maintained under this permit, including
monitoring reports or reports of compliance or noncompliance
shall, upon conviction , be punished by a fine of up to
$10,000 per violation, or by imprisonment for not more than 3
months, or by both.
It shall not be a defense for a permittee in an enforcement
action that it would have been necessary to halt or reduce the
permitted activity to maintain compliance with the conditions
of the permit.

(1) Reapplication for Permit Renewal.
Permittee is not authorized to discharge after the expiration
rate set forth herein. In order to receive authorization to
discharge beyond the expiration date, the perm�ttee shall
submit such information, forms and fees as are required by the
agency authorized to issue permits no later than 180 days
prior to such expiration date.
All reports or information submitted pursuant to the
requirements of this permit must be signed and certified by a
ranking official or duly authorized agent of the permittee.
After reapplication of permit this permit may be modified,
revoked and reissued or terminated with cause in accordance to
the requirements of the City of Henderson Sewer Use Ordinance
and North Carolina General Statute or implementing
regulations.
(m)
Dilution Prohibition.
The permittee shall not increase the use of potable or process
water in any other way to attempt to dilute the discharge as
a partial or complete substitute for adequate treatment to
achieve compliance with the limitations contained in this
permit.
(n) Construction.
No construction of wastewater treatment facilities or
additions thereto shall be begun until final plans and
Specifications have been submitted to the City and/or the DWQ
and written approval and authorization to construct has been
issued.
(o) Sludge Management Plan.
Ninety days prior to the initial disposal of sludgy generated
by any pretreatment facility the permittee shall submit a
sludge management plan.
(p) Categorical Standard Reopener.
This permit shall be modified, or alternatively, revoked and
reissued, to comply with any applicable effluent standard or
limitations issued or approved under Sections 302 (b) (2) (c)
and (d), 304 (b) (2), and 307 (a) (2) of the Clean Water Act,
if the effluent standard or limitation so issued or approved:
(1) Contains different conditions or is otherwise more
stringent than any effluent limitation in this permit; or
(2) Controls any pollutant not limited in this permit.
The permit as modified or reissued under this paragraph shall
also contain any other requirements of the act then
applicable.
14

(q) General Prohibitive Standards.
The permittee shall comply with the General Prohibitive
Discharge Standards in 40 CFR 403.5 (a) and (b) of the Federal
Pretreatment Regulations.
(r) Certified Operator.
Pursuant to Chapter 90A of North Carolina General Statutes,
the permittee shall employ a certified wastewater treatment
plant operator in responsible charge of the wastewater
treatment facilities. Such operator must hold a certification
of the grade equivalent to the classification assigned to the
wastewater treatment facilities.
(s) Permit Modification, Revocation, Termination of -Permit.
This permit may be modified, revoked, and reissue or
terminated with cause in accordance to the requirements of the
City of Henderson Sewer Use Ordinance and North Carolina
General Statutes or implementing regulations.
(7) NONCOMPLIANCE: ENFORCEMENT.
Any failure to continuously meet and comply with the
provisions of the Ordinance and this permit, and any
misrepresentation or failure to fully disclose all relevant fact in
the Application shall constitute a violation of this permit, and
the City is, if it determines that such violation constitutes an
immediate danger to the operation or maintenance of the City's
Sanitary Sewer System or to the wastewater treatment plant, or if
it determines that such violation cannot be cured within what he
deems to be a reasonable time, authorized immediately upon written
notification mailed or delivered to permittee at the location set
forth below, to terminate this permit or suspend implementation of
steps by permittee necessary to achieve compliance. IN the event
the City determines that such violation does not constitute an
immediate danger to the operation or maintenance of -the City's
Sanitary Sewer System or the Waste Treatment Plant and that such
noncompliance can be cured within a reasonable time, it shall
inform permittee by written notice of the violation and provide
what it, in the exercise of its judgement, deems to be a reasonable
time to achieve compliance. If compliance is not achieved within
such time allotted by the City, it is authorized to assert any
remedies for noncompliance. Discharges by permittee into the
City's sewer system following termination, suspension or expiration
of this permit are unlawful, and in the event of such unlawful
discharge, the City is authorized to:
(a) discontinue water service to permittee's facility;
(b) disconnect permittee's connection to the city's sewer
system; and/or
(c) take such other requirements as may be available at law
or equity to prevent such unlawful discharge and otherwise
enforce the Ordinance and the provision of this permit.
15

The foregoing remedies are cumulative and not exclusive, and the
exercise of one or more shall not preclude the exercise of any
other remedy at a subsequent time. In addition, the failure to
exercise remedy or other indulgence or extension of time of
whatever nature or duration granted by the City in the event of
violation shall in no event constitute a waiver or the right to
exercise any or all of such remedies, may be exercised at any time.
A

uu,, J, Y. " pt, In Ue, i i. IJ7i uy.[1.4� AM
Page 1 0l6
ATTACHMENT A
REFRACTORYTOXICITY ASSF.SSIIENT PROTOCOI.
1.1 OVERVIF.NIOF RTA PROTOCO1,
The general Refractory Toxicity .-sessment (RTA) procedure described b\ EPA t 1939a t has peen
adapted to evaluate sources of toxicity at the City of Henderson•s Nutbush Creel WWTP. The RTA
procedure involves treating industrial user (IL') \waste\water in a bench -scale. batch simulation of the
WWTP•s treatment system. which includes: the trickling filter. oxygen -nitrification\. and tertian
filtration processes. Following treatment. the simulation effluents are analyzed for chronic toxicity.
Tine RTA procedure determines the -refractor- toxicity of the \wastewater. which is the toxicity that
\could be expected to pass through the NVWTP and contribute to effluent toxicity.
RTA testing utilizes t\wo r,pes of simulations:
A control simulation treating WWTP influent (including industrial and domestic \vaste%%ater).
which provides baseline data on the treatment provided by the WWTP. and
A test simulation treating IL- wastewater spiked into NVWTP influent. which provides
information on the potential contribution of tovcit}• b%. the IL'.
Toxiciq• test results for the simulations spiked with It- wastewater are compared to results for tilt
control simulation. Evidence of refractory toxicity contribution would be indicated by greater toxiciry
in the spiked simulation effluent relative to the control.
During testing; chemical oxygen demand (COD). ammonia -nitrogen. and suspended solids
measurements are also taken to confirm that the performance of the RTA simulations are comparable
to the XVNVTP performance.
A.2 RTA DESIGN AND OPERATION
A.2.1 Sample Collection
The following samples should be used in RTA testing:
T\venty-Four hour composite sample of NVWTP influent collected prior to the primary
clarifiers at the Nuthush WWTP
Grab samples of return activated sludge (RAS) collected from the return sludge linos
for the o% gen-nitrification process
T%\enty-four hour composite sample ofthe II.' discharge
A- I

ryga I Oil
A11 \xastetcater samples should be collected in the t%tentN -four hour period urunediateI\
pre ;dins RT.� testing (i.e., final collection on the counting of testing)..-Ul samples. ex%:ept the
RAS. should be maintained at 4°C during sample collection. Tte RAS sample should he
colhected on the den of testing and brought umnediately to the laboratonfor use in testi:tg.
.a" Simulation Set -Up and Operation
4. 2.2.1 .Sample Preparation
Influent for the control simulation tests consists of \ W17P influent. Approximatch 3 liters of
\NAVTP influent should be poured into a clean ?': gal bucket.
4, Influent for spiked simulation tests consists of the IL' wastewater spiked into %\1CTP influent.
The proportion of IL' wastewater to influent is based on the flow contribution o'. the
to the WIVTP. A conservative flow condition of maximum it: flow to minimum N1" XTP
flow (1.9 MGD) is used to calculate the spike volumes.
y _ �1taKlPlo« �y
sm.A-ara�
Eight liters of the IL" wastewater WWTP influent mixture should be placed into a clear.
gal plastic bucket.
i, A 200 ml subsample of each RTA test influent should be collected for COD and anunonia-
nitrogen analysis. A summary of recortunended analytical methods is provided in Table A-1.
.4.2.2.1 Trickling Filter Set- Up and Operation
6. Bench -scale trickling filters should consist of-f-etch diameter. 3 it PVC columlts filled with
_stonc-media collected from one of the \utbuslt'V\'WTP first -stage trickling filters. Two
columns should be constructed: one for the IL' -spiked wastewater and another for the control.
The bortom of the columns should be reduced to I" or less to provide support for the stone
media.
Influent wastewater should be fed from the buckets to the top of each column using a
Peristaltic pump set at a flow rate that is comparable to design NV %VTP trickling filter flow rate
(i.e.. 3 to 4 gal hour cu ft media). The column effluent should be collected in the same
buckets and recirculated continuous]\- to the top of tte column. Pumping should continue for
a ' hour period. %inch corresponds to the hydraulic residence time of the WWTP trickling
f i I tens.
A-2

1. _.. r......-... ....-.. UJ., I. - , ra...
rage J of b
Samples of (he nitluenl and final colufrul e fluent (after, = hours) should be collected anc:
allal\Zed for COD to deternute if remol al efficiencies are similar to \1 \\ TP removal
efficiencies. The :olu[ruis should be cleaned %nth potable water, and the trickling filter fnedia
should be replaced before treating additional samples.
4 2.2.J BioreaetorSet-Up
9 The final trickling titter effluents should be allowed to settle for at least I (tour and the
clarified supernatants should be prepared for treatment in bench -scale, batch o\-,¢en-
nitrification bioreactors. These batch bioreactors should consist of 5 gallon non -toxic. plastic
containers outfitted with air tubing and air stones. A medical grade pure Oxygen suppl is
required for this stage of testing. _
.4- 2. ?.3 .-I crivared .Shidg a Biomass
10. Upon receipt of the RAS sample. the sample volume should be recorded. the sample shculd be
thoroughly mixed, and an aligout should be taken for total suspended solids (TSS) analysis. A
graduated carboy is recommended because volume measurements will be taken during
preparation of the RAS sample.
1 1. While the TSS analysis is being performed. the RAS sample should be rinsed to remove
potential residual toxicity. The rinse step involves mixing the bion.ass with a non -toxic
laboraton• dilution hater (DEH\R 1991). First, the RAS sample should be allowed to settle
for about l hour. then the clarified supernatant should be decanted and the remaining volume
of settled solids should be recorded. Laboraton• dilution water should then be added to bring
the total volume back to its original level. The mixture should be aerated for at least one hour
and then the solids should be allowed to settle again.
] 2. The RAS sample will need to be thickened relative to its origutal TSS concentration. The
target RAS TSS concentration is 12.000 mg I. Once the TSS concentration of the orieLial
RAS sample is known. the degree of thickening can be determined by the following equation:
DacanrVolwne =otalSamplal'oluma *OrrginalSamplarSS
rargatrsS
1= A sufficient volume of thickened RAS (\'as) should be added to the bioreactors to achi.:ve a
target mixed liquor suspended solids (\ILSS) of about 4.000 mg I. The volume of RAS to be
added should be calculated using the following equation:

.......... ,1. 1)J. VJ.'I.y' -. ,
rage a of p
1VLSSr�V:., .
aces TSS abnaemr
au
shore. \ILSSra, is the target mixed liquor suspended solids (\ILSS) concentration tit
the test biureactors
TSSK S is the suspended solids concentration of the thickened R..kS
\xM....,.. is the total volume of the test bioreactor
-4.2.2.4 Hioreactor Operation _
1 The Volume of trickling filter simulation effluent to be treated in tht 0.xNSen-nitrification
hioreactors should he calculated as follows:
vlYte}fpy<FflbrFQ4uia vabrna--vats
The minimum total bioreactor volume should he at least 6 liters to ensure a sufficient final
sample Volume for toxicity testing.
15. Tlu R.-\S and trickling filter effluents for the IL' spiked test and control should be comb.tted
and pure oxygen should be applied to maintain adequate mixing of the mixed liquors.
16. The bioreactors should be aerated for 3 ' + hours. which corresponds to the HRT of the
aeration basin under average flow conditions. Periodic pH and dissolved ox}•gen
measurements should be taken to monitor bioreactor operation.
17. A substantial amount of alkalinity is consumed in tite nitrification process (7.1,mg per `:H3
oxidized). To ensure sufficient alkalinity for complete nitrification. lime mac netd to be
added A lime solution should be obtained from die \utbush Creek \V%VTP for this purpose.
If neetsssan, lime should be added to maintain a pH in the mixed liquors of 6.5 to 6.3.
13. Following treatment, the mixed liquors should be allowed to senle for about one hour and ill,:
clarified effluents should he filtered as described helots.
a..2.3 Final Filtration
19 Filtration tllruught a laburaton' ,glass -fiber filter has been found to produce effluent of qt.alijx
that is similar to that obtained by filtration tlrou_h a pilot -scale simulation of the \RCTP';
tertian filters. Therefore. the clarified biureactor effluents should be filtered through a zlass-
fiber filter (1 to 10 _m nominal pore size). The laboraton filter holder and sample collection
container should be thuruuehlt- cleaned and rinsed before use and between :amples..-k
A; J

r Jqc 3 Of o
mmunum of I gallon of filtered effluent s, ill be needed for tox;cit\ testing.
--0 -\ _00 ml subsa nple of the final filtered samples should be : Hi _ ed and anelszed for C OD.
atmnottia-nitrogen. and TSS.
-1.2.4 Sample Delis en and Toxicity Testing
= I The final filtered effluents should be placed in clean glass contauters for shipment. Tlte:;e
samples should be delivered within 24 hours to a DEH\R vended laborator.
22. Upon receipt, the laboraton should irrunediately begin testing of the samples using a modified
chronic Geriodaphnro dubra toxicity test (DEH\R 1991). The toxicity tests should consist of
fine effluent concentrations (100. 75. 50. 25 and 1_.5 percent) and a control with 10 replicates
per concentration. Each RTA sample should be used for test irtitiation and renewal on days 3
and 5 of the toxicity• test. Samples should be held at -I°C between test renewals.
A-3 DATA i\TERPRET.AT1O\
.t..3.1 Conventional Pollutant Treatment Performance
23. During the simulation tests, samples are collected for COD. ammonia -nitrogen, and TS:i. The
overall removal of these conventional pollutants in the RT.-\ tests should be within the r:7rroval
efficiencies (i.e.. trickling filter influent vs. final filtered effluent) and final diluent
concentrations observed at the W"*TP as stated below:
COD - 35 to 990 0
ammonia -nitrogen - no more than l mg I
TSS - 95 to 990n
A.3.2 Ref -actom Tosicin• Determination
2 t — L'sing data from the toxicity tests, the inhibition concentration value to 230.o of the tact
organisms (IC..) should be calculated for each sample. The toxicity results for the IU-spiked
test are compared to the control simulation results. Evidence of refractory toxicity• would be
provided if the effluent toxicity of the IL spiked test is greater than the toxicity• of the ccntrol
el luent. For example. refractor' toxicitp would be indicated if the IL --spiked test effluent had
an IC.. value of 400 o compared to an IC., value of 601 o for the control.
25. The IU discharge will be defined as a source of refractor- toxicirv. if the IC., of the IU-spiked
test effluent is less than the IC,. of the control effluent and the 950o confidence intervals for the
IC., values do not overlap.
_ _;

Yayc 0 JI 0
Table A-1. City of Henderson Refractotn' Toxicity .assessment . Summary of Recommended
.-1nah-tical Methods
Parameter
Reference
Method Number
nonia•%itrogtn
rDissohrdO��grn
(L'SEP.a 1933)
(L'SEP.�.1983)
(L'SEP.k 1983)
_,r,�;
360.1
140.1
Temperature
(L'SEP.k 1983)
170.1_
Total Suspended Solids
(L'SEP..=L 1983)
160.2
Chemical O-\gen Demand
(Hach. 1987)
N
Chronic Canodaehnia Toxicity Test
(DEH\'R 1991)
100,
\.A = Not Applicable
N
.Adi

AMERIGIL
C O R P C R ,r T C N
March 17.1999
Tom Spain
Waste Water Treatment Plan
PO Box 1334
Henderson, NC 27536
Dear Mr. Spain
This letter is to notify you that America! Corporation will be changing some of the
processes in the Dye House. The Dye House has begun bleaching cotton socks on a
limited bases. The new process will displace approximately 25% of the current sheer
hosiery production. This should result in a reduction of dye stuff and surfactant usage.
Approximately 300 gallons of 12.5% Chlorine bleach,120 gallons of 35%Peroxide and
300 pounds of Q-13 which is a Peroxide Stabilizer (MSDS Sheets Attached) each day
Sincerely
Jeff Golliher
Superintendent of Dyeing
cc, Bill Bailey
319 Amorital Road • Past 0liice Sex 1419 1 Nonderson N( 27536 • (2521 492 2166

THE PROGRAM EXPENDITURES
1996-97 - $97,591.12
1997-98 - $95,092.68
1998-99— $76,126.06
1999-2000 - $17,744.25
Total $286,554.11
Note: The reduction in expenditures from 1996 to 1999 was the result of reducing
monitoring of certain industries and sections of sewer because no toxicity was present
and increased in-house use of microtox to screen for toxicity.

NORTH CAROLINA DEPARTMENT OF o
ENVIRONMENT A'`1^ NATURAL RESOURCES
AGM
NCDEN.R .
JAMES B. HUNTJR.
GOVERNOR
_ WAYNE MCDEVITT v-
SECRETARY
KERR T. STZJENS
DIRECTOR
._.VISION OF WATER QUALITY
0, .Pls
I WJ�LI,
August 4, 1999
Mr. Robert F. McGhee
Director, Water Management Division
United States Environmental Protection Agency
Region 4
Atlanta Federal Center
61 Forsyth Street
Atlanta, Georgia 30303-8960
Subject: Revised Implementation Policy for Copper and Zinc Action Levels
Dear Mr. McGhee:
This letter responds to your letter of July 16, 1999 in follow-up to our June 30,
1999 meeting in Raleigh regarding the North Carolina Division of Water
Quality's action level approach to controlling the discharge of copper and zinc
through NPDES outfalls. The Division appreciates your willingness to consider
North Carolina's innovative approach to controlling the impact of these two
metals on aquatic life.
Enclosed are the following:
1) Policy for Implementation of Action Levels for Copper and Zinc in NPDES
Permits, July 23, 1999
2) North Carolina's procedure for determining reasonable potential
3) Flow diagram of the action level implementation procedure process
4) A draft Notice of Violation in response to whole effluent toxicity (1VVET)
noncompliances specifically designed for facilities that monitor for copper and
zinc
5) North Carolina's recently revised enforcement policy for whole effluent
toxicity
The policy will be immediately applied to the following facilities:
Henderson Nutbush
NCO020559
Reidsville WWTP
NC0024881
Spindale WWTP
NCO020664
Star WWTP
NCO05854
Stanley WWTP
NC0020036
Oxford Southside WWTP
NCO025054
Cone Mills
NC0000876
P.O. BOX 2953S. RALEIGH, NORTH CAROLINA 27626.0535
- PHONE [phone] FAX [phone]
AN EQUAL OPPORTUNITY / AFFIRMATIVE ACTION EMPLOYER - 50% RECYC1_E0/10% POST.CONSUMER PAPER

The Division's first step will be to develop a proposed permit limit as described in
the policy for these facilities. That value will be input into the Division's
reasonable potential analysis along with available historical monitoring data for
copper and zinc to determine the reasonable potential to exceed the proposed
limit. The facilities that show a reasonable potential to exceed the proposed limit
will be notified by letter. As many of these facilities have already begun TIE
activities and/or may be under a Special Order by Consent, the context presented
in their notification letters will be somewhat different than that of the enclosed
example NOV. However, the requirements and timetables will remain the same.
Note that Metal Industries (NC0057819) is not included in the list above. This
facility is under special order and undergoing the necessary capital improvements
to convert to a non -discharge system by October 1, 2000.
The Division again extends its thanks for the Agency's patience and flexibility in
addressing this issue. If you have questions regarding this letter or the enclosed
materials, please call Coleen Sullins, Water Quality Section Chief, at (919) 733-
5083, extension 550.
Sincerely.
V:,t�
Kerr T. Stevens
Enclosures
cc: w/o attachments
Gail Mitchell, EPA Region
Bill Melville. EPA Region 4
Lvdia Mavo, EPA Region 4
Lisa Spurlin. EPA Region 4
Greg Thorpe
Coleen Sullins
Dave Goodrich
Dianne Reid
Susan Wilson
Matt Matthews

,Ity of Henderson Office of
P. O. Box 1434 City Manager
180 Beckford Drive Eric M. Williams
Henderson, NC 27536
[e-mail]
Phone:[phone] Fax."252/492-4322
July 281h, 1999
Mr. Ken Schuster
Regional Supervisor
Raleigh Regional Office
Department of Environment
and Natural Resources
1628 Mail Service Center
Raleigh, North Carolina 27699-1628
RE: Follow Up from our July 27`r' meeting
Special Order by Consent EMC WQ No. 96-05
Dear Mr. Schuster:
First of all, please accept my appreciation for you and your various NCDENR
colleagues meeting with Tom Spain, Mark Warren, John Botts and me yesterday
regarding our ongoing efforts to fully comply with all the conditions of the above Order.
As you know, we do continue to struggle with the issue of toxicity and, while we
have made what we believe are significant strides, continue to be concerned that
full compliance in this area by the September 30th, 1999 deadline (as outlined in
SOC paragraph 2 (c) 5), which we discussed at some length yesterday, appears
extremely problematic.
In your ongoing review of the toxicity issue, we are aware of additional work to be
done and, as promised yesterday, we will go ahead and prepare a specific
chronological recap of the particular chain of events involving Americal which we
reviewed yesterday. That communication will be sent directly to both Dana Foley and
Tom Poe, but also copied to you and the others in attendance at yesterday's meeting to
be sure the sharing of information is both timely and complete. You will be receiving
this information as soon as it has been prepared.
On the matter of full and complete compliance with chronic toxicity, please
consider this a preliminary request for a one year extension (until September 30th,
2000) with this particular part of our Order. In considering this, you are aware that
we have tried diligently to identify and solve our toxicity problems and, at this point,
have been unable to do so on a consistent basis. For example, prior to February, 1999
we had 4 out of 5 months in compliance, 3 of which were consecutive; however, then
our June results were significantly out of compliance. We have required the biggest
suspect industry, Americal Corporation, to conduct 2 RTAs and an in-house TRE. We
H:lletterslschuster7-28-99.doc Page 1 of 2

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will take enforcement action if it is proven that they are a source of toxicity. The variable
of the toxicity has made it very hard to locate. Also, the type of toxicity has not been
easy to identify. Several HPLC analyses have indicated that it was a nonpolar organic
and possibly a surfactant. We have found that the technology for sample analyses
needed to locate a problem such as ours is very imprecise. We are now working with
our 2"d consultant and 3`d laboratory and have spent hundreds of thousands of dollars
over the past 3 years trying to solve our toxicity problem. We request that you consider
our efforts, commitment, and funding allocated to solving our toxicity problem when
deciding if you will grant our request for a 12-month extension in our SOC with regard to
toxicity.
We will continue with activities on this end relative to this matter and, as I
mentioned yesterday, I believe it would be beneficial for us to meet again some
time during early September to discuss our status at that point. In this regard we
will in touch with you again at the appropriate time.
Again, thank you for your ongoing assistance and we'll look forward to meeting
with you again in the relatively near future. With my best regards, I am
EMW/dew
C: Mr. Mark Warren
Mr. Tom Spain — Note to Mr. Spain —
Very truly yours,
CITY OF HENDERSON
Er Wil ams
City ger
Pis. see to it that this letter is also
copied to John Botts and everyone in
attendance at our meeting yesterday.
Tom, don't forget — all mailings now,
aside from going to the particular
office, are to be sent to the Statewide
Central Mail Service Center ... please
check whether or not the other
offices use the 1628 prefix.z/ ^EMW
v L�
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