PRELIMINARY REPORT
USEPA 3ENCH SCALE WASTEWATER TREATABILITY STUDY
PULP AND PAPER MILL DISCHARGES
OF 2373-TCDD and 2373-TCDF
PROPOSED INTERIM CONTROL MEASURES
INTERIM NPDES PERMIT STRATEGY
OCTOBER 1988
U.S. ENVIRONMENTAL PROTECTION AGENCY
REGION 5 - ENVIRONMENTAL SCIENCES DIVISION
EASTERN DISTRICT OFFICE
WESTLAKE, OHIO
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ACKNOWLEDGMENTS
This report was prepared by Gary A. Amendola, U.S. Environmental Protection
Agency Region 5. Field sampling was conducted under the direction of Daniel S.
Granz, USEPA Region 1, and David R. Barna, USEPA Region 5. Treatability
experiments were conducted by David Lovejoy, E.C. Jordan Co. Analyses for
2378-TCDD and 2378-TCDF were conducted at the 3rehm Laboratory, Wright State
University under the direction of Dr. Thomas 0. Tiernan. The principal reviewers
of this report were Danforth G. Bodien, USEPA Region 10; David R. Barna and
Jonathan Barney USEPA Region 5; Daniel S. Granz, USEPA Region 1; Donald F.
Anderson and Wendy D. Smith, USEPA Industrial Technology Division, Office of
Water Regulations and Standards; and Gary W. Hudiburgh, USEPA Permits Division,
Office of Water Enforcement and Permits.
DISCLAIMER
This document has been reviewed in accordance with U.S. Environmental
Protection Agency policy and approved for distribution. Mention of trade names
or commercial products does not constitute endorsement or recommendation
for use.
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TABLE OF CONTENTS
>; e
I. INTRODUCTION 1
II. OBJECTIVES 3
III. "INDINGS AND CONCLUSIONS 3
IV. STUDY DESIGN 4
V. FIELD PROGRAM 4
VI. ANALYTICAL PROGRAM 5
VII. SUMMARY OF RESULTS 5
A. Distribution of 2373-TCDD and 2378-TCDF 5
in Wastewater Samples
3. Bench Scale Wastewater Treatability Study 9
C. Other Observations 12
VIII. PROPOSED NPDES PERMIT SPECIAL CONDITIONS 16
REFERENCES
LIST OF ATTACHMENTS
ATTACHMENT
1 Proposed Interim Chlorine Minimization Program
2 Proposed Interim Effluent Suspended Solids
Minimization Program
i i
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I. INTRODUCTION
The formation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (22^3-"C"C; 3".:
2,3,7,3-tetrachlorodibenzofuran ( 2373-TCDF) in the bleaching of certain
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These limited findings suggest that major process modifications sucn is
installation of oxygen delignification systems at existing bleach lines ^
installation of completely new bleaching sequences nay be effective it
significantly reducing formation of 2378-TCDD and 2373-TCDF and other toxic
pollutants. Also, the degree of chlorination and chlorine dioxide substitution
in conventional bleaching lines may signi ficantl y affect the formation of
2378-TCDO and 2378-TCDF. Additional research is underway to determine the
mechanisms of formation of 2378-TCDD and 2378-TCDF and the process modifications
that will be most effective at minimizing or eliminating formation of these
compounds. Results from this research are expected during the next few years.
Although decisions to install oxygen delignification and other bleaching
process modifications have been made for several mills, implementation of
process modifications across the industry, if warranted, may be a relatively
long-term proposition.
Human health risks associated with formation of 2378-TCDO and 2378-TCDF in
pulp and paper mills and the distribution of these materials in the environment
through contamination of paper products, wastewater discharges, and wastewater
sludges are currently under review. Although most estimates of potential health
risks in terms of excess cancers are relatively low, the highest risks are
estimated where contaminated materials are directly ingested (e.g., consumption
of contaminated fish) (USEPA 1988c,d); or where 2~"'8-TCDD and 2378-TCDF are
transferred from a paper product to a material that $ ingested (e.g., transfer
from coffee filters to coffee) (A.D. Little 1987, : AS I 1988b). The industry
estimates that dermal contact with paper products normal food contact with
paper products, and inhalation of paper dusts by aper mill workers do not
result in significant health risks (NCASI 1987a,b; 1988c). Also, risks to
surfers and swimmers from exposure to pulp mill effluents in the ocean through
dermal adsorption and ingestion were estimated to be quite low (Radian 1988).
Several states have issued fish consumption advisories for segments of
streams with paper mill discharges where native fish have been found to be
contaminated with 2378-TCDD at levels of concern (Minnesota 1985, Wisconsin
1985, Maine 1985, Louisiana 1987). Other fish consumption advisories are
anticipated as additional data become available through USEPA's bioaccumulative
pollutant study and monitoring by states. Because of the high incidence of
native fish contamination downstream from pulp and paper mills, the U.S.
Environmental Protection Agency has determined that, as part of an interim
strategy for regulating pulp and paper mills, short-term measures to limit
discharges of 2378-TCDD and 2378-TCDF should be taken where possible (USEPA
1988e).
Based upon these considerations, the USEPA Office of Water Regulations and
Standards - Industrial Technology Division, in cooperation with Regions 1 and 5,
undertook a wastewater characterization and preliminary (bench scale) treata-
bility study at two of the mills from the five-mill study. This study was
focused on the distribution of 2378-TCDD and 2378-TCDF in various untreated and
treated wastewater samples and possible removal of these materials from
the wastewater streams through chemically assisted clarification. While the
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Industry chose not to participate financially or assist in the design j r"
study, NCASI did provide assistance to USEPA in identifying current s
treatment practices at a number of mills with respect to coagulant and eol/ner
addition for suspended solids control.
This report presents a preliminary summary of the study findings ind
proposed interim control measures that can be implemented througn J5E?V s
interim regulatory strategy. A more detailed technical report including a fjll
discussion of the field and analytical programs, estimates of sludge generation,
and preliminary engineering cost estimates for installation and operation of
chemical 1y assisted clarification systems is in preparation.
II. OBJECTIVES
1. Determine the aqueous and solid phase distribution of 2378-TCDO and
2378-TCDF in untreated and treated wastewaters from two bleached kraft pulp and
paper mills with known contamination.
2. Determine whether, or to what extent, 2378-TC00 and 2378-TCDF can 5e
removed from untreated, partially treated, and treated bleached kraft pulp and
paper mill wastewaters through chemically assisted c1^rification.
3. Develop proposed interim (i.e., short-t- n) control measures for
2378-TC00 and 2378-TCDF that can be implemented throi n USEPA's interim strategy
for regulating dioxins in pulp and paper mills.
III. FINDINGS AND CONCLUSIONS
1. While some fraction of 23 78-TC DO and 2378-TCDF in internal untreated
pulp and paper mill bleachery wastewaters (i.e., caustic extraction stage
filtrates, combined bleach plant wastewaters) is associated with suspended
solids, most of the 2378-TCDD and 2378-TCDF is in the aqueous phase of those
wastewaters or in fine colloidal suspensions.
2. After biological treatment at two mills, more than 90% of the
2378-TC00 and 2378-TCDF is associated with suspended solids and subsequently is
transferred to the sludge or discharged with the suspended solids in the
effl uent.
3. Chemically assisted clarification appears to be an effective mechanism
for control of 2378-TCDD and 2378-TCDF in internal plant wastewaters. However,
as an interim control measure, improved suspended solids controls in existing
treatment facilities can more quickly and easily be implemented at less cost.
4. Limited data from the five-mill study, supplemental data obtained as
part of this study, and data from Scandinavian studies indicate that chlorine
minimization and chlorine dioxide substitution programs in bleacheries can
significantly reduce formation of 2378-TCDD and 2378-TC OF.
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IV. STUDY DESIGN
The bench scale wastewater treatability study was conducted in t*o phases.
Phase 1 consisted of screening the effectiveness of various coagulants iid
polymers for suspended solids removal from samples of caustic extraction starje
filtrate, combined bleach plant wastewaters, aeration basin effluent prior to
settling, and final effluent, all obtained from Mill E as designated in the
five-mill study (see USEPA 1988a). Phase 2 consisted of performing chemically
assisted clarification studies on a second set of samples obtained at Mill E
and a set of similar samples obtained at Mill A from the five-mill study.
Those coagulants and polymers determined to be most effective from the Phase I
screening program were tested at various dosages and combinations in Phase 2.
Caustic extraction stage filtrates and combined bleach plant wastewaters were
selected for the treatability study since data from the five-mill study
indicated these streams contained the highest levels of 2378-TCDO and 2378-TCDF
(USE PA 1988a).
The untreated samples obtained for the Phase 2 program were analyzed for
2378-TCDD and 2378-TCDF in both the aqueous and solid phases as were those
treated samples from the bench scale studies exhibiting the best performance
with respect to total suspended solids. Samples of gravity settled (in
laboratory) aeration basin effluents were analyzed " - 2378-TCDO and 2378-TCDF
in similar fashion.
V. FIELD PROGRAM
Samples for the Phase 1 screening program were obtained at Mill E by
personnel from the USEPA Region 1 Environmental Services Division (ESD) and
E.C. Jordan Co., Portland, Maine. Samples for the Phase 2 program were collected
by Region 1 ESD personnel at Mill E and by Region 5 Environmental Sciences
Division personnel at Mill A. In each case, four grab samples were collected
to prepare an eight-hour composite sample at each sampling site. Samples were
shipped or transported to an E.C. Jordan laboratory in Portland, Maine, where
the chemically assisted clarification studies were conducted.
Bench scale jar tests were performed to evaluate the effectiveness of
various coagulants and polymers for total suspended solids (TSS) and total
organic carbon (TOC) removal from the untreated wastewater streams. A six-
paddle gang stirrer was used to perform the tests. After flocculation, samples
were allowed to settle for 30 minutes, which is less than the detention time in
conventional clarification systems for secondary biological solids.
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VI. ANALYTICAL PROGRAM
Analyses for TSS and TOC were performed by E.G. Jordan Co. ;siig j3EA
approved analytical methods. Analyses for 2373-TCOD and 237S-"C;~ «ere
performed by the Brehm Laboratory - Wright State University using the s a in p i e
extraction, extract clean-up, and analytical protocol developed fir t^e
five-mill study with a modified three-phase column for concurrent iscmer-
specific determinations of 2378-TCDD and 2378-TCDF. Criteria for identification
and quantitation of 2378-TCDO and 2378-TCOF were attained. However, for
selected samples with low levels of solid material , the desired analytical
detection levels of 0.01 parts per trillion (ppt) were not achieved. This is
primarily a function of the requested separate analyses of the solid and aqueous
phases of each sample. This problem was particularly evident for the final
effluent and treated samples from Mill E. The untreated Phase 2 samples from
Mill E had much lower levels of 2378-TCDD and 2378-TCDF than similar samples
obtained during the five-mill study. In retrospect, the analytical protocol
for aqueous samples used in the five-mill study would have been preferable for
attaining 1ower detection limits. That protocol included combining the extracts
from separate extractions of the solid and liquid phases for each sample prior
to analysis.
VII. SUMMARY OF RESULTS
A. Distribution of 2373-TCDO and 2378-TCDF in Waste iter Samples
Tables 1 and 2 present the analytical results ,r 2378-TCDD and 2378-TCDF
in untreated and partially treated wastewaters and the final effluents from
Mills A and E, respectively. Table 3 presents final effluent data for two
California pulp mills that have no end-of-pipe treatment and discharge to the
ocean. These data show that substantial fractions (601-701) of the 2378-TCDD
and 2378-TCDF found in caustic extraction stage and combined bleach plant
wastewaters are in the aqueous phase. Also, that 351-501 of the 2378-TCDD and
2378-TCDF found in combined untreated wastewaters from pulping and bleaching are
in the aqueous phases of those wastewaters. All of the untreated wastewaters
are high in organic content. It is theorized that 2378-TCDD and 2378-TCDF are
codissolved with the organic species or are in colloidal suspensions that pass
through the fine laboratory filters used to separate the aqueous and solid
fractions of each sample.
Of particular importance is the finding that nearly all of the 2378-TCDD
and 2378-TCDF in aeration basin mixed liquor suspended solids is found on the
suspended solids. It is likely that as other organics are oxidized in biological
treatment systems, 2378-TCDD and 2378-TCDF, which are refractory to conventional
biological treatment, are taken up with food by the active microorganisms or are
adsorbed onto the cell walls. This finding is consistent with the distribution
of 2378-TCDD and 2378-TCDF in primary and secondary wastewater treatment sludges
observed in the five-mill study (USEPA 1988a) and findings at the Dow Chemical
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TABLE 1
MILL A
DISTRIBUTION OF 2378-TCDO AND 2373-TCDF
IN SOLID AND AQUEOUS PHASES
Sample 2378-TCDD 2378-TC3F
Wastewater Sample Number Phase (X) (pg/gm or ppt) (X) (pg/gm or ppt
Caustic Extraction DE027804S Solid 37 35
Filtrate DE027804W Aqueous 63 65
[TSS 40 mg/L] Total 0.50 2.15
Combined 31 each DE027803S Solid 32 35
Plant DE027803W Aqueous 68 65
[TSS 86 mg/L] Total 0.20 0.88
Aeration 3asin DE027802S Solid >98 >99
Effluent Prior to DE027802W Aqueous <2 <1
Settling Total 0.84 .85 2.63
[TSS 3700 mg/L]
Final Effluent DE020801S Solid >75 75
[TSS 23 mg/L] DE020801W Aqueous <25 25
Total 0.009-0.012 0.043
Notes: (1) Wastewater concentrations of 2378-TCDO and 2378-TCDF are reported as
picograms/gram (pg/g) or parts per trillion (ppt).
(2) Where 2378-TCDO or 2378-TCDF were not detected in either the solid
phase or aqueous phase of a sample, the distribution between the
solid phase and aqueous phase was estimated assuming the analyte
was present at the detection level for that fraction of the sample.
(3) Where a range of concentrations is presented, the values reported
represent the minimum and maximum concentrations. The minimum
concentration was estimated by assuming that the analyte concen-
tration was zero when not detected in a fraction. The maximum
concentration was estimated by assuming that the analyte was
present at the detection level.
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TABLE 2
MILL E
DISTRIBUTION OF 2378-TCDD AND 2378-TCOF
IN SOLID AND AQUEOUS PHASES
Sample 2378-TCDD 2378-TCDF
Wastewater Sample Number Phase (%) (pg/gm or ppt) JJJ (pg/gm or ;pt':
Caustic Extraction 88911S Solid -- 31
Filtrate 88911W Aqueous -- 59
[TSS 240 mg/L] Total ND(0.024) 0.069
"BM 31 each Line 88913S Solid -- >30
[TSS 410 ng/L] 88913W Aqueous -- <70
Total ND(0.014) 0.027-0.087
Wation Basin 88910S Solid >92 92
Huent Prior to 88910W Aqueous <8 8
- w.tl ing Total 0.1C .11 0.74
l iSS 840 mg/L]
Final Effluent 38909S Solid -- 41
[TSS 44 mg/L] 88909W Aqueous -- 59
Total ND(0.044) 0.15
Notes: (1) Wastewater concentrations of 2378-TCDD and 2378-TCDF are reported as
picograms/gram (pg/g) or parts per trillion (ppt).
(2) Where 2378-TCDD or 2378-TCDF were not detected in either the solid
phase or aqueous phase of a sample, the distribution between the
solid phase and aqueous phase was estimated assuming the analyte
was present at the detection level for that fraction of the sample.
(3) Where a range of concentrations is presented, the values reported
represent the minimum and maximum concentrations. The minimum
concentration was estimated by assuming that the analyte concen-
tration was zero when not detected in a fraction. The maximum
concentration was estimated by assuming that the analyte was
present at the detection level.
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TABLE 3
CALIFORNIA PULP MILLS
DISTRIBUTION OF 2378-TCDD AND 2373-TCDF
IN SOLID AND AQUEOUS PHASES
Sample 2378-TCD0 2378-TCDF
Sample Number Phase (t) (pg/gm or ppt) (t) (pg/gm or ppt',
Mill 1
Final Effluent IPGH117 Solid 64 50
[TSS 120 mg/L] Aqueous 36 50
Total 0.10 0.63
Final Effluent 2PGH117 Solid 66 56
(duplicate) Aqueous 34 44
Total 0.11 0.63
Mill 2
Final Effluent 5PGH117 Solid 56 45
[TSS 113 mg/L] Aqueous 44 55
Total 0.36 7.59
Final Effluent 6PGH117 Solid 59 48
(duplicate) Aqueous 41 52
Total 0.36 7.42
NOTE: 1. Wastewater concentrations for 2378-TCDD and 2378-TCDF are reported
as picograins/gram (pg/g) or parts per trillion (ppt).
2. The final effluents at both mills are comprised of essentially
untreated wastewaters from pulping and bleaching.
3. Samples collected November 1987 by USEPA-Region 9.
4. Analyses for 2378-TCDD and 2378-TCDF by Brehm Laboratory,
Wright State University, Dayton, Ohio (see Section VI for
analytical protocol).
5. Analyses for total suspended solids by Kennedy/ Jenlcs/Chil ton,
San Francisco, California.
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Michlgan Division plant at Midland, Mic
indicate that effective separation of mi
aeration basin suspended solids is a key
of 2378-TCDD and 2378-TCDF.
higan (USEPA 1936). These iata :"ear'/
xed liquor suspended solids and extended
factor i n minimi zing effluent liscnarges
8. Bench Scale Wastewater Treatability Study
The Phase 2 bench scale results are summarized in Tables 4 and 5, for
Mills A and E, respectively. As noted earlier, the unexpectedly low levels of
2378-TCDD and 2378-TCDF in Mill E samples and the low levels of solid material
in the treated samples confounded the analytical program and rendered analysis of
much of the treatability data for that mill inconclusive.
The results for Mill A demonstrate that more than 95S of the 2378-TCDD and
2378-TCDF present in caustic extraction stage and combined bleach plant
wastewaters was removed through chemically assisted clarification. However,
the substantial dosages of alum (2000 mg/L) or lime (1500 mg/L) required for
treatment would result in generation of large quantities of sludge from the
suspended sol ids removed, any al um or 1 ime in excess of saturation, and dissolved
and colloidal materials taken out of solution. In order to implement this type
of treatment on a full-scale basis, separate clarification and sludge dewaterlng
facilities would be required at most mills. Estimates of the quantities of
sludge generated and preliminary engineering cost e :imates will be presented
in the final technical report for this study.
For the aeration basin mixed liquor suspended :lids, use of a non-ionic
polymer (dosage 6.25 mg/L) resulted in improved suspended solids effluent
quality over laboratory gravity settling (17 mg/L vs. 70 mg/L). The level of
suspended solids attained was also somewhat lower than the full-scale treatment
system final effluent discharge of 23 mg/L attained without the use of polymers
or settling aids, but with longer settling time. 2378-TCDD and 2378-TCDF were
removed to less than detectable levels (detection level 0.016 ppt). The actual
final effluent concentration of 2378-TCDD was 0.009-0.012 ppt vs. <0.016 ppt in
the "treated" aeration basin effluent sample. The 2378-TCDF in the final
effluent was 0.043 ppt vs. <0.016 ppt in the polymer-treated aeration basin
effluent. Unfortunately, the prescribed analytical protocol precluded attain-
ment of desired lower detection levels in the "treated" samples. Use of the
same polymer at a lower dosage for the Mill E aeration basin effluent appeared
to be less effective for removal of TSS, 2378-TCDD and 2378-TCDF.
The final effluent at Mill A was subjected to treatment with alum (200 mg/L)
and a cationic polymer (4.0 mg/L). Marginal improvement of effluent quality is
indicated with respect to TSS and 2378-TCDF. Results for 2378-TCDD are
inconclusive due to the analytical issues noted earlier. Treatment of a final
effluent in this manner as an interim measure would not be practical because of
the need for installation of additional large-scale clarification facilities.
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'ABLE 4
MILL A
USEPA BENCH SCALE PAPER MILL WASTEWATER TREATABILITY 3"JOY
PRELIMINARY SUMMARY OF RESULTS
Jntreated
T reated
i Removal
Veat^ent
Caustic Extraction
TSS
TOC
2378-TC DD
2378-TCDF
40
290
0.50
2.15
13
150
<0.019
<0.039
55X
481
>96X
>981
A1 jm ( 2000 'Tig/ L )
Nalco 7769 ( 7 . 5 Tig/
(anionic)
Combined Bleach Plant
TSS
TOC
2 3 78-T C DO
2378-TCDF
86
190
0.20
0.88
19
120
<0.010
<0.011
781
37X
>95 X
>98X
Lime (1500 mg/L)
Calgon 'AT 2439
(5.0 ng/L)
(cationic)
Aeration Basin Effluent
TSS
TOf
2378-TCDD
2378-TCDF
3700
400
0.84-0.85
2.63
70
57
<0.030
0.091
)8X
]6X
36X
36X
Gravity Settling
No Ad d i t i v e s
Aeration Basin Effluent
TSS
TOC
2373-TCDD
2378-TCDF
3700
400
0.84-0.85
2.63
17
48
<0.016
<0.016
>99X
38X
>98X
>99%
American Cyanamid
1906 N (6.25 mg/L)
(non-ionic)
Final Effluent
TSS
TOC
2373-TCDD
2378-TCDF
23
48
0.009-0.012
0.043
15
22
<0.043
<0.02
35X
54X
>53X
AT urn (200 mg/L)
Calgon 2136 (4.0 mg/L)
(cationic)
Notes: 1. Analytical results for total suspended solids (TSS) and total
organic carbon (TOC) are reported in mg/L (or ppm); analytical
results for 2378-TCDD and 2378-TCDF are reported in pg/gm (or ppt)
2. Analyses for TSS and TOC by E.C. Jordan Co.
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TA8LE 5
MILL E
USEPA BENCH SCALE PAPER MILL WASTEWATER TREATABILITY STUDY
PRELIMINARY SUMMARY OF RESULTS
Untreated
Treated
% Removal
Treatment
Caustic Extraction
"3" Bleach Line
TSS
TOC
2378-TCDD
2 3 73-TC DF
240
550
<0.024
0.069
16
250
<0.014
<0.009
931
551
>87X
Lime (5000 mg/L]
Calgon WT 2439
(3.0 mg/L)
(cationic)
Combined "B" Bleach Line
TSS
TOC
2378-TCDD
23 78-TC DF
410
400
<0.014
0.027-0.087
31
200
<0.020
<0.008
921
501
>701
Lime (5000 mg/L)
Calgon WT 2439
(3.0 mg/L)
(cationic)
Aeration Basin Effluent
TSS
TOC
2378-TCDD
23 73— TC DF
840
180
0.10-0.11
0.74
160
110
<0.030
0.13
:x
n
it
>15
Gravity Settling
No Additives
Aeration Basin Effluent
TSS
TOC
2378-TCDD
2378-TCDF
840
180
0.10-0.11
0.74
39
97
<0.054
0.35
95 J
461
>48%
531
American Cyanimid
1906 N (5.0 mg/L)
(non-ionic)
Final Effluent
TSS
TOC
2378-TCDD
2378-TCDF
44
93
<0.044
0.15
21
32
<0.027
<0.011
521
662
>921
Alum (400 mg/L)
Nalco 7769 (3.5 mg/;
(anionic)
Notes: 1. Analytical results for total suspended solids (TSS)
organic carbon (TOC) are reported in mg/L (or ppm);
results for 2378-TCDD and 2378-TCDF are reported in
2. Analyses for TSS and TOC by E.C. Jordan Co.
and total
analytical
pg/gm (or ppt)
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Although Installation of facilities for treatment of internal
wastewaters (caustic extraction stage filtrates, combined bleach olant
waters) might appear to be an effective method for reducing effluent ii scarves,
the time required for installation, the additional sludge generated, :o3si5'e
difficulties in sludge dewatering, and the relatively high costs argue against
this alternative. A more effective interim measure would be improved saso^naa.:
solids controls in existing treatment facilities. At nost pulp and paper
mills, facilities for addition of clarification chemicals (e.g., coagulants,
polymers) have been installed or can be installed quickly at relatively low
cost. Also, the incremental sludge generated can be handled within the
capability of existing sludge dewatering facilities at most mills. Similar
treatment shoul d al so be feasi bleat many mills wi th extended aeration wastewater
treatment facilities.
C. Other Observations
Tables 6 and 7 present comparisons of results obtained in the five-mill
study with results obtained in the treatability study for Mills A and E,
respectively. These comparisons illustrate two important points: (1) signifi-
cantly lower levels of 2378-TCDO and 2378-TCDF were found in bleach plant
wastewaters with lower bleaching rates (application of chlorine and chlorine
derivatives) in C-stages and across the bleach lir s; and (2) significantly
lower effluent discharges of 2 378-TC DO and 2378-TCOF .-re observed with improved
suspended solids control. Bleach plant operating ;ata for Mill E for the
treatability study have been claimed confidential a ' have not been presented
here. Notwithstanding, the degree of bleaching t each mill during the
treatability study sampling as measured by unbleached, partially bleached, and
fully bleached pulp characteristies (K, CEK, final brightness) was about the
same as that measured during the five-mill study. Based upon limited results
from other studies (OMOE 1988, USEPA 1988a, STFI 1988), the changes in levels
of 2378-TCDO and 2378-TCDF presented in Tables 6 and 7 are believed to be
principally related to changes in bleaching practice rather than laboratory,
random process, or chemical reaction rate variability. These limited data
indicate that an effective interim strategy for minimi zing effluent discharges
of 2378-TCDD and 2378-TCDF should include both chlorine minimization and
improved suspended solids controls.
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TABLE 6
HILL A
FIVE-MILL STUOY AND TREATABILITY STUDY
CHLORINATION PRACTICE AND 2378-TC00/2378-TCDF LEVELS
Chlorination Practice^
Five-Mill Study
June 1986
Treatibil i ty
St jdy 1
December 1987
C-Stage (softwood)
Bleach Line (softwood)
C-Stage (hardwood)
Bleach Line (hardwood)
Bleach Plants
75 lbs/ton
60 lbs/ton
235
121
66
41
128
75
162
99
Pulp Characteristics
Softwood
K (unbleached) 19.6 20.3
CEK 3.0 2.8
Final Brightness * *
Hardwood
K (unbleached) 11.8 12.4
CEK 2.9 3.0
Final Brightness * *
Wastewater
Caustic Extraction
2378-TCDO
1.8 pp+
0.50 ppt
Stage (softwood)
2378-TCDF
33
2.2
Combined Bleach Plant^
2378-TCDO
0.44
0.20
2378-TCDF
7.6
0.88
Aeration Basin Effluent
2378-TCDO
NA5
0.84-0.85
Prior to Settling
2378-TCDF
NA
2.6
Final Effluent
2378-TCDD
0.12
0.009-0.012
2378-TCDF
2.2
0.043
TSS
104 ppm
23 ppm
NOTES: 1. Treatability study results for 2378-TCDD and 2 378-TC OF (Oecember
1987) are for native wastewater samples prior to addition of
any coagulants or polymers.
2. Chlorination practice expressed as lbs C^EQOX/ton of air-dried
brownstock pulp (see USEPA 1988a, pp. 92-103).
3. 81each plant chlorination practice is production weighted for
hardwood and softwood bleach lines.
4. Combined bleach plant sample for the five-mill study represents
mathematical composite of softwood and hardwood bleach line
filtrates. Combined bleach plant sample for treatability study
represents field composite sample obtained from combined bleach
plant sewer.
5. NA - Not analyzed in five-mill study.
* Oata not presented.
-13-
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TABLE
7
MILL E
FIVE-MILL STUDY AND TREATABILITY ST'JOY
CHLORINATION PRACTICE AND 2373-TC00/2378-TCDF
LEVELS
Five-Mill Study
January 1987
Tredtibil i1y
Studyl
December 1937
Chlorination Practice^
Cp-Stage (hardwood)
Bleach Line (hardwood)
Bleach Plant^
98 lbs/ton
156
193
** lbs/ton
** '•
Pulp Characteristies
So ftwood
K (unbleached)(PN)
CEK
Final Brightness
Hardwood
K (unbleached)(PN)
CEK
Final Brightness
13.3
3.0
*
16.7
2.3
*
**
**
**
**
**
**
Wastewater
Caustic Extraction
Stage (hardwood)
23 78-TC DD
2378-TCDF
3.6 ppt
14
<0.024 ppt
0.069
3 Bleach Line^
2378-TC DD
2378-TCDF
2.1
5.80
<0.014
0.027 to <0.087
Combined 31 each Plant^
2378-TCDD
2378-TCDF
1.3
5.3
NA6
NA
Aeration 8asin Effluent
Prior to Settling
2378-TCDD
2378-TCDF
NA6
NA
0.10-0.11
0.74
Final Effluent
2378-TCDD
2378-TCDF
TSS
0.09
0.42
89 ppm
<0.044
0.15
44 ppm
NOTES: 1. Treatability study results for 2378-TCDO and 2378-TCDF (December
1987) are for native wastewater samples prior to addition of
any coagulants or pol/ners.
2. Chlorination practice expressed as Ids CI 3 EQOX/ton of air-dried
brownstock pulp (see USEPA 1988a, pp. 92-103).
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TABLE 7
MILL E
FIVE-MILL STUDY AND TREATABILITY STUDY
CHLORINATION PRACTICE AND 2378-TCDO/2378-TCDF LEVELS
NOTES: continued...
3. Ch1or1nation practice for bleach plant is production weighted
for hardwood and softwood bleach lines.
4. "B" bleach line sample for treatability study represents field
composite of "B" bleach line (hardwood) filtrates. "A" bleach
line (softwood) was down during treatability study sampling
program. "B" bleach line sample for five-mill study represents
mathematical composite of "8" bleach line filtrates.
5. Combined bleach plant sample for five-mill study represents a
mathematical composite of "A" bleach line and "B" bleach line
filtrates.
6. NA - Not analyzed in five-mill study or not sampled in
treatability study.
* Data not presented.
** Bleach plant chemical application and pulp : :a claimed confidential.
-15-
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VIII. PROPOSED NPOES PERMIT SPECIAL CONDITIONS
To date, there Is only one industrial discharger in the United States w ;-i
a specific process wastewater discharge limitation for 2373-TCDD :r 2 3 73-TjF.
In May 1984 , the Michigan Water Resources Commission issued a Final Order ; f
Abatement for the Dow Chemical - Michigan Division plant at Midland, Michigan,
and a concurrent NPDES permit (MWRC 1984 a,b). The NPDES permit prohibited Me
discharge of detectable levels of 23 78-TCDD and prohibited the discharge
"... at a level which is or may become injurious ... ." The Final Order
established a final water-qual i ty based effluent limitation of 0.3 parts per
quadril 1 ion (ppq) 2 378-TC DD and interim effluent 1imitations of 50 ppq effective
until December 31, 1985, and 10 ppq for the period January 1, 1986 to June 30,
1988. The Final Order also set out a dioxin minimization program including a
requirement for an interim control program consisting of the installation of a
mixed-media wastewater effluent filter. Upon installation of the effluent
filter, the discharge from Dow Chemical has consistently contained less than
10 ppq 2 3 78-TC DD. Recently, the Michigan Water Resources Commission issued an
amended -inal Order of Abatement and reissued the NPDES permit for Dow Chemical
(MWRC 1988 a,b). 3y these actions the state has revised the final water-quality
based effluent limitation from 0.3 ppq to 0.1 ppq 2373-TCDD, and the interim
effluent limitation from 10 ppq to 8 ppq. Further dioxin minimization programs
and treatability studies have also been required, "his approach has resulted
in significantly reduced effluent discharge levels d reduced 2 3 78 - TC 00 levels
in native fish collected from the receiving water ( IEPA 1988d).
USEPA's interim strategy for regulation of , Jp and paper mill dioxin
discharges requires development of appropriate best professional judgment
(8PJ) best available technology (BAT) effluent limitations and suggests the use
of chlorine minimization and improved suspended solids control programs as
mechanisms to develop those limitations (USEPA 1988e). Current data indicate
that both of these mechanisms are likely to result in reduced effluent discharges
of 23 78-TC DO and 2378-TCDF. Attachments 1 and 2 present proposed NPDES
permit special conditions for chlorine minimization and improved suspended
sol ids control , respectively. These conditions can be applied in permits as
they are reissued or as modifications to permits currently in effect. The
specific requirements should be tailored to site-specific conditions at each
mill, taking into account any recent progress that may have been made through
programs initiated by the paper companies.
The treatability data presented in this report are the result of bench
scale studies at two pulp and paper mills. While the treatability data and
supplemental information presented here provide insight into approaches for
interim measures to reduce effluent discharges of 2378-TCDD and 2378-TCDF,
the data are too limited to establish interim BPJ BAT NPDES permit effluent
limitations for these compounds at al 1 bleach kraft pul p and paper mills. Until
such time as more data become available, approaches that establish near-term
target levels in the range of 10 ppq (0.01 ppt) are suggested. The data from
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the f1ve-m11l study, data from other researchers, and the limited data presented
here indicate that discharges of 2378-TCDO and 2378-TCOF In the range of 13 opq
are attainable with changes in bleaching practice and improved suspended solids
controls. The interim control programs are reasonable interim measures that
can be taken to work toward attainment of water-qual i ty based effluent
limitations that may be applicable to many pulp and paper mills.
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REFERENCES
A.D. Little 1987, Exposure and Risk Assessment of Oioxin in Bleached Kraft
Paper Products (draft report), USEPA Contract No. 63-01-6951, Work Assign-
ment No. 18, Amendment No. 1, Arthur D. Little Inc., Cambridge, Massachusetts,
June 25, 1987.
Buckeye Cellulose 1988, Byrd, J.F., The Buckeye Cellulose Corporation, Memphis
Tennessee, to (Farrar, Michael C., vice president, Environmental and Health
Affairs, American Paper Institute Inc., Washington, DC), July 8, 1988, 2 pp.
Consolidated Paper Inc. (CPI) 1987, Oioxin/Furan In-Mill Source and Environ-
mental Studies Report, Consolidated Papers Inc., Wisconsin Rapdis, Wisconsin,
November 1987 (Amended February 1988).
Louisiana Department of Environmental Quality (Louisiana) 1987, Elevated Levels
of Dioxin Reported from Northeast Louisiana Watershed (news release) , Baton
Rouge, Louisiana, November 23, 1987.
Maine Departments of Environmental Protection, Human Services, and Inland
Fisheries and Wildlife (Maine) 1985, Dioxin in Androscoggin River (news
release), Augusta, Maine, May 20, 1985.
Minnesota Department of Health and Minnesota Pollution Control Agency (Minnesota)
1985, 2,3,7,8-TCDO Discovered in Rainy River F i s ¦ (news release), St. Paul,
Minnesota, October 29, 1985.
Michigan Water Resources Commission (MWRC) 1984a, Final Order of Abatement No.
2022, Cosigned by Michigan Department of Natural Resources and Michigan
Attorney General, Lansing, Michigan, May 17, 1984.
Michigan Water Resources Commission (MWRC) 1984b, NPDES Permit MI0000868, Dow
Chemical U.S.A. - Michigan Division (May 17, 1984 - June 30, 1988), Lansing,
Michigan, May 17, 1984.
Michigan Water Resources Commission (MWRC) 1988a, Final Order of Abatement No.
2120, Cosigned by Michigan Department of Natural Resources and Michigan
Attorney General, Lansing, Michigan, September 15, 1988.
Michigan Water Resources Commission (MWRC) 1988b, NPDES Permit MI0000868, Dow
Chemical U.S.A. - Michigan Division (October 3, 1988 - October 1, 1993),
Lansing, Michigan, September 15, 1988.
National Council of the Paper Industry for A1r and Stream Improvement Inc.
(NCASI) 1987a, First Progress Report on the Assessment of Potential Health
Risks from Use of Bleached Board and Paper Food Packaging and Food Contact
Products, Special Report 87-11, National Council of the Paper Industry for
Air and Stream Improvement Inc., New York, New York, November 1987.
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-2-
National Council of the °aper Industry for Air and Strewn
(NCASI) 1987b, Assessment of Potential Health Risks from Dermal Epos-"*
Dioxin in Paper Products, Technical Bulletin No. 534, National :ounc:l ;ff
the Paper Industry for Air and Stream Improvement Inc., New vork, 'tew 't-<,
November 1987.
National Council of the Paper Industry for Air and Stream I^iarovement
(NCASI) 1988a, Gillespie, William J., Program Director Water Duality,
National Council of the Paper Industry for Air and Stream Improvement Inc.,
New York, New York, to (O'Farrell, Thomas, Acting Director, Industrial
Technology Division, U.S. Environmental Protection Agency, Washington, DC)
July 22, 1988, 6pp.
National Council of the Paper Industry for Air and Stream Improvement Inc.
(NCASI) 1988b, Assessment of the Risks Associated with Potential Exposure
to Dioxin Through the Consumption of Coffee Brewed Using Bleached Paper
Coffee Filters, Technical Bulletin No. 546, National Council of the 3aper
Industry for Air and Stream Improvement Inc., New York, New York, May 1988.
National Council of the 3aper Industry for Air and Stream Improvement Inc.
(NCASI) 1988c, Risks Associated with Dioxin Exposure Through Inhalation of
Paper Dust in the Workplace, Technical Bulletin ~ 537 , National Council
of the Paper Industry for Air and Stream Impro. ient Inc., New York, New
York, January 1988.
Ontario Ministry of the Environment (OMOE) 1988, (raft N111 Effluents in
Ontario (Prepared by the Expert Committee on Kraft Mill Toxicity), Pul p
and Paper Sector of MISA, Toronto, Ontario, Canada, April 1988.
Radian Corporation (Radian) 1988, Health Risk Assessment for Dioxin for Furan
Compounds Present in Humboldt Bay Pulp Mill Effluents, Radian Corporation,
Sacramento, California, May 19, 1988.
Swedish Pulp and Paper Research Institute (STFI) 1988, Bleaching and the
Environment (Addendum to paper presented by K. P. Kringstad, et al., STFt,
Stockholm, Sweden at 1988 International Pulp Bleaching Conference, Orlando,
F1 orida), June 1988.
U.S. Environmental Protection Agency (USEPA) 1986, Michigan Dioxin Studies, Dow
Chemical Wastewater Characterization Study, Tittabawassee River Sediments
and Native Fish, U.S. Environmental Protection Agency, Region 5, Westlake,
Ohio 44145, EPA-905/4-88-003, June 1986.
U.S. Environmental Protection Agency (USEPA) 1987, The National Dioxin Study,
Tiers 3, 5, 6, and 7, Office of Water Regulations and Standards, Washington,
DC 20460, EPA-440/4-87-003, February 1987.
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-3-
U.S. Environmental Protection Agency (USEPA) 1988a, U.S. EPA/Paper Industry
Cooperative Dioxin Screening Study, Office of Water~i Officer 57 Water
Regulations and Standards, Washington , OC 20460, EPA-440/1-88-025, March
1988.
'J.S. Environmental Protection Agency (USEPA) 1988b, USEPA/Paper Industry Coop-
erative Dioxin Study, Washington, OC, April 25, 1988.
U.S. Environmental Protection Agency (USEPA) 1988c, Risk Assessment for Dioxin
Contamination - Midland, Michigan, Region 5, Chicago, 111inois 60604, EPA-
905/4-88-005, April 1988.
U.S. Environmental Protection Agency (USEPA) 1988d, Proposed Risk Management
Actions for Dioxin Contamination - Midland, Michigan, Region 5, Chicago,
Illinois 60604, EPA-905/4-88-006, April 1988.
U.S. Environmental Protection Agency (USEPA) 1988e, Interim Strategy for the
Regulation of Pulp and Paper Mill Dioxin Discharges to Waters of tne United
States, Office of Water, Washington, DC, August 9, 1988.
Wisconsin Division of Health and Department of Natural Resources (Wisconsin)
1985, Health Advisory for Fish Eaters, Summary of Wisconsin Fishing
Regulations, Madison, Wisconsin, 1985.
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ATTACHMENT 1
Proposed Interim Chlorine Minimization Program
1. Within 30 days from the effective date of this permit, the permittee shall
conduct a 72-hour composite sampling program of the following points at
each bleach line for the purpose of establishing the rates of formation of
2378-TCDD and 2378-TCOF (lbs/ton of air-dried brownstock pulp) with current
bleaching practice:
Pul ps
a. Brownstock pulp fed to first stage chlorination
b. Fully bleached pulp after last bleaching stage.
Wastewaters
a. Combined bleach plant wastewaters exclusive of noncontact cooling
waters, process wastewaters from pulping, chemical recovery, paper
machines, utilities or other nonbleach plant sources to the extent
possibl e.
b. If it is not possible to sample combined blea:h plant wastewaters sepa-
rately, individual bleach line filtrates and other bleach plant waste-
waters shall be sampled for the 72-hour sampling period. The permittee
may analyze each filtrate separately or prepare a flow-weighted
composite sample of filtrates and other bU ich plant wastewaters for
analyses, insuring that the composite sample is representative 1n terms
of flow and composition of each wastewater.
2. The permittee shall retain all bleach plant operating logs for the period
beginning 24 hours prior to initiation of sampling and lasting until 24
hours after completion of sampling. A minimum of 24 grab samples shall be
taken at approximate equal-time intervals to make up each 72-hour composite
sample.
3. The samples shall be analyzed for 2378-TCDD and 2378-TCDF in accordance with
the analytical protocol set out in Appendix C of USEPA/Paper Industry
Cooperative Dioxln Serening Study (EPA 440/1-88-025, March 1988) or other
equivalent analytical protocol approved by USEPA.
4. Within 90 days from the effective date of this permit, the permittee shall
submit a report including the results of the sampling program, the rates of
formation of 2378-TCDD and 2378-TCDF, and a description of the bleaching
practice followed (e.g., all chemical additions in lbs/ton of air-dried
brownstock pulp, Kappa number, CEK, and all data necessary to compute the
Kappa factor or chlorine ratio).
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-2-
5. Beginning 30 days from the effective date of this permit and 'a;'.:'1] :ir
120 days, the permittee shall review bleach plant operating practices inj
develop operating practices to minimize, to the -naximum extent jricJcal
without compromising product specifications, the use of elemental :nlorv^
for pulp bleaching. Operating practices nay include control of :h1:riie
application, greater substitution of chlorine dioxide for chlorine rfhe'-e
possible, improved mixing of bleach chemicals, and other operating practices
which would result in lower chlorine use.
6. Within 120 days from the effective date of this permit and lasting until
the expiration date, the permittee shall implement those practices that
are feasible. Within 150 days from the effective date of this permit, the
permittee shall submit a report describing the results of its chlorine
minimization efforts.
7. Within 180 days from the effective date of this permit, the permittee shall
conduct a second bleach plant nonitoring program (see paragraphs 1 to 4
above). The permittee shall submit a report of that monitoring program not
later than 240 days from the effective date of this permit.
3. Beginning 12 months after the effective date of this permit and continuing
at six-month intervals, the permittee shall subr a report describing any
further actions it has taken to minimize chlor :e use in pulp bleaching
including, but not limited to, changes in operating practices, process
modifications, and process substitutions.
9. Based upon the results of this program, the permitting authority may reopen
this permit for modification, as appropriate.
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ATTACHMENT 2
Proposed Interim Effluent Suspended Solids Minimization Program
1. Within 30 days from the effective date of this permit, the permittee shall
initiate laboratory scale screening studies for the purpose of determining
what coagulants, polymers, or other materials or additives, may be most
effective for minimizing the discharge of total su-spended solids from the
final effluent. For mills with biological treatment systems including
secondary clarifiers, the testing shall be conducted on samples of
biological treatment system effluent (aeration basin) prior to addition of
any treatment chemicals and prior to settling in secondary clarifiers. For
mills with aerated stabilization basins without secondary clarifiers, the
testing shall be conducted at the entry or influent to the final settling
zones prior to discharge. The testing shall include as a control a gravity
settled sample of the secondary clarifier or final setting zone influent
including any treatment chemicals currently used at dosages reflecting
current practice.
2. Within 30 days from the effective date of this permit, the permittee shall
obtain 72-hour composite samples of the final effluent and the biological
treatment system effluent (aeration basin) prior .o addition of any treat-
ment chemicals and prior to settling in secondary clarifiers or final
settling zones as noted above. The aeration basin sample shall be analyzed
for 2378-TCDD and 2378-TCDD in both the solid frac :ion (laboratory filtered)
and the liquid fraction in accordance with the analytical protocol set out
in Appendix C of 'JSEPA/Paper Industry Cooperative Dioxin Screening Study
(EPA 440/1-88-025, March 1988) or equivalent analytical protocol approved
by USEPA. The final effluent sample 2378-TCDD and 2378-TCDF analytical
results shall be reported on a total sample basis (i.e., separate extraction
of solid and liquid fractions, but analysis of combined extracts in
accordance with the above analytical protocol).
3. Within 60 days from the effective date of this permit, the permittee shall
report the results of the laboratory-scale screening studies and the
analyses of the final effluent and aeration basin effluent for 2378-TCDD
and 2378-TCDF. The permittee shall also submit a study plan for pilot
plant or full-scale verification of the laboratory-scale screening study.
4. Within 75 days from the effective date of this permit, the permittee shall
initiate pilot-scale or full-scale total suspended solids wastewater treata-
bility studies for the purpose of validating the results of the laboratory-
scale screening studies. If pilot-scale treatability studies are conducted,
the studies shall be conducted at a scale that would permit implementation
of the results on a full-scale basis.
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-2-
5. Within 150 days from the effective date of this permit, the permittee
submit a report of the pilot-scale or full-scale total suspended :o',
wastewater treatability studies. The report shall include the complete
study results; estimates of the increased amounts (volume and lass) Df
wastewater sludge generated; estimates of expected total suspended sol'is
effluent quality; estimates of the investment and annual costs issociated
with improved suspended solids controls; and a proposed construction
schedule should additional facilities be required.
6. Beginning 150 days after the effective date of this permit and lasting
until expiration, the permittee shall implement the most effective interim
effluent total suspended solids controls derived from the above studies
within the capability of existing wastewater treatment and sludge dewatering
facilities. Installation and operation of chemical or other material
addition facilities shall be considered within the scope of "existing
wastewater treatment," if those facilities are not in place, or if
modification of existing chemical or other material addition facilities is
re qui red.
7. Based upon the results of this program, the permitting authority may reopen
this permit for modi fication , as appropriate.
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