[Federal Register Volume 59, Number 2 (Tuesday, January 4, 1994)]
[Rules and Regulations]
[Pages 458-469]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 93-32032]


[[Page Unknown]]

[Federal Register: January 4, 1994]


_______________________________________________________________________

Part V





Environmental Protection Agency





_______________________________________________________________________



40 CFR Parts 260 and 261




Hazardous Waste Management System; Identification and Listing of 
Hazardous Waste; Wastes From Wood Surface Protection; Final Rule
ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 260 and 261

[FRL-4804-9]

 
Hazardous Waste Management System; Identification and Listing of 
Hazardous Waste; Wastes From Wood Surface Protection

AGENCY: Environmental Protection Agency.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The U.S. Environmental Protection Agency (EPA) is issuing a 
final hazardous waste listing determination for wastes generated from 
the use of chlorophenolic formulations in wood surface protection 
processes. Upon reviewing the public comments received on its proposal 
of April 27, 1993, the Agency has decided not to list wastes from the 
use of chlorophenolic formulations in wood surface protection 
processes. As a result of this determination, EPA is not mandating in 
this rule any specific operating or information collection requirements 
for owners/operators of wood surface protection plants. If, however, 
use of chlorophenolic formulations resumes in the future, the Agency 
would very likely re-evaluate this decision not to list. This rule also 
finalizes the proposed amendment of SW-846 (``Test Methods for 
Evaluating Solid Waste, Physical/Chemical Methods'') to include Method 
4010 (Immunoassay Test for the Presence of Pentachlorophenol). In 
addition, the Agency is adding the following four chemicals to 40 CFR 
part 261, Appendix VIII: Sodium and potassium salts of 
pentachlorophenol and tetrachlorophenol.

EFFECTIVE DATE: January 4, 1994.

ADDRESSES: The official record for this rulemaking is identified as 
Docket Number F-93-F33F-FFFFF and is located in the EPA RCRA Docket, 
room M2616, 401 M Street, SW., Washington, DC 20460. The public must 
make an appointment to review docket materials by calling (202) 260-
9327. The docket is open from 9 a.m. to 4 p.m., Monday through Friday, 
excluding holidays. The public may copy up to 100 pages from the docket 
at no cost. Additional copies cost $0.15 per page.

FOR FURTHER INFORMATION CONTACT: For general information, contact the 
RCRA/Superfund Hotline at (800) 424-9346 (toll-free) or (703) 920-9810 
in the Washington, DC metropolitan area. The TDD hotline number is 
(800) 553-7672 or (703) 486-3323. For technical information on specific 
aspects of this rulemaking, contact Mr. David J. Carver at (202) 260-
6775, Office of Solid Waste (Mailcode 5304), U.S. EPA, 401 M Street, 
SW., Washington, DC 20460. For technical information relating to the 
amendment of SW-846, contact Ms. Gail Hansen at (202) 260-4761, Office 
of Solid Waste (Mailcode 5304), at the same address provided above.

SUPPLEMENTARY INFORMATION: The contents of today's preamble are listed 
in the following outline:

I. Legal Authority
II. Background & Summary
III. Overview of the Proposed Rule
IV. Summary of Public Comments and Responses
    A. General Comments
    B. Comments Regarding Risk Assessment
V. Overview of the Final Rule
    A. Basis for the Determination Not to List As Hazardous Wastes 
From Wood Surface Protection Operations
    B. Operating Requirements for Surface Protection Plants
    C. Addition of Chemicals to Appendix VIII of 40 CFR part 261
VI. Amendment of SW-846 (Test Methods for Evaluating Solid Waste, 
Physical/Chemical Methods)
VII. Pollution Prevention and Waste Minimization
VIII. Analysis of Potential Costs and Benefits
    A. Executive Order Requirements
    B. Description of Costs and Benefits of this Rule
IX. State Authority
X. Regulatory Flexibility Analysis
XI. Paperwork Reduction Act

I. Legal Authority

    These regulations are being promulgated under the authority of 
sections 2002(a) and 3001(b) and (e)(1) of the Solid Waste Disposal 
Act, as amended, 42 U.S.C. 6912(a), 6921(b) and (e)(1), and 6922 
(commonly referred to as RCRA).

II. Background & Summary

A. Background

    Under section 3001(e) of RCRA, as amended by the Hazardous and 
Solid Waste Amendments of 1984 (HSWA), EPA is required to make a 
hazardous waste listing determination for wastes containing chlorinated 
dioxins and dibenzofurans. As part of this mandate, the Agency began an 
investigation in 1988 of dioxin-containing wastes from wood preserving 
and wood surface protection processes. Three categories of wastes from 
wood preserving processes were listed as hazardous wastes in 1990, 
(F032, F034, and F035, see 55 FR 50450). A final listing determination 
for wood surface protection process wastes were deferred due to lack of 
data (53 FR 53282). In 1991, the Agency began a separate study of the 
surface protection industry in an effort to obtain sufficient 
information upon which to base a hazardous waste listing determination. 
The Agency, upon obtaining and evaluating information, published a 
proposed rule on April 27, 1993 which proposed a concentration-based 
hazardous waste listing option and requested comment on an alternative 
option not to list these wastes as hazardous (58 FR 25707). Details of 
the options can be found in the following section to this preamble. A 
detailed summary of all Agency actions related to wood surface 
protection wastes was provided in the April 27, 1993 proposal (58 FR 
25707). The reader is encouraged to consult that document for more 
information on the wood surface protection rulemaking history.
    In accordance with a proposed consent decree signed by EPA and the 
Environmental Defense Fund (EDF) in EDF v. Browner (U.S. District Court 
for the District of Columbia, case no. 89-0591), the Agency has agreed 
to make a final listing determination for chlorophenolic wastes from 
wood surface protection processes by December 31, 1993.

B. Summary of the Wood Surface Protection Regulation

    After considerable review and study of the rulemaking docket for 
this action, including comments received on the proposal, the Agency 
has determined that listing as hazardous wastes from surface protection 
operations is unnecessary and will not yield the benefits intended by a 
hazardous waste listing under the RCRA program. This section summarizes 
elements of the proposed rule of April 27, 1993 (58 FR 25707), and 
details the conclusions reached in developing this final rule. The 
reader is cautioned that although some of the highlights brought up in 
the proposed rule are described below, the majority of information on 
the industry itself as well as the detailed risk assessment on which 
the initial proposed rule was based is found in the preamble and 
background documents to the proposed rule. The information contained in 
this final rule is primarily concerned with developments subsequent to 
the proposed rule. This rule describes, in detail, the Agency's 
justification for not listing wastes from surface protection processes 
that use chlorophenolic formulations. In addition, it summarizes the 
Agency's response to comments received on the proposal.

III. Overview of the Proposed Rule

    The April 27, 1993 proposal discussed and requested comment on each 
of the following:
    (1) Proposing a concentration-based hazardous waste listing for 
certain wood surface protection wastes,
    (2) Proposing various testing, analysis, recordkeeping requirements 
and management standards for wood surface protection plants,
    (3) Adding six hazardous constituents to appendix VIII of 40 CFR 
part 261,
    (4) Amending of appendix VII of 40 CFR part 261 by adding F033 and 
the hazardous constituents found in the wastes,
    (5) Modifying the Comprehensive Environmental Response, 
Compensation, and Liability Act (CERCLA) list of hazardous substances 
to reflect the newly proposed listing,
    (6) Amending SW-846 (``Test Methods for Evaluating Solid Waste, 
Physical/Chemical Methods'') to include Method 4010 (Immunoassay Test 
for the Presence of Pentachlorophenol), and
    (7) An alternative option not listing chlorophenolic wastes as 
hazardous.
    The Agency proposed to list as hazardous at 40 CFR 261.31 only 
those wastes from wood surface protection processes using a formulation 
with a pentachlorophenate concentration greater than 0.1 ppm. Under 
this proposed option, surface protection operations using formulations 
with pentachlorophenate concentrations equal to or less than 0.1 ppm 
would not generate F033 listed wastes. The Agency proposed this 
concentration-based listing because it had information which suggested 
that many surface protectors who previously used chlorophenolics did 
not sufficiently clean out equipment prior to abandoning the use of 
chlorophenolics. Because of this, many formulations from past users of 
chlorophenolics exhibit ``cross-contamination,'' the contamination of 
current formulations by dioxins and chlorophenolic compounds from old 
formulations. The rule proposed the following hazardous waste listing 
description for the F033 waste code and included the following specific 
waste streams from process operations:

    F033:Process residuals, wastewaters that come into contact with 
protectant, discarded spent formulation, and protectant drippage 
from wood surface protection processes at plants that use surface 
protection chemicals having an in-process formulation concentration 
of pentachlorophenate (expressed as pentachlorophenol during 
analysis) exceeding 0.1 ppm. (T)

    Along with this option, various testing and recordkeeping 
requirements were proposed. For an owner/operator to demonstrate that 
he/she is not generating F033 wastes, EPA proposed formulation testing 
requirements for all surface protection plants. All owner/operators of 
wood surface protection plants would be required to test their 
formulation to determine the concentration of pentachlorophenate if the 
owner/operators wanted to avoid generating F033 wastes. If the analysis 
showed a concentration at or below 0.1 ppm, the owner/operator would be 
required to sign a certification to that effect and maintain records on 
site related to the testing procedure. This testing proposed an 
analysis using a method listed within the EPA's Test Methods for 
Evaluating Solid Waste, Physical/Chemical Methods (SW-846). The Agency 
proposed to add Method 4010 to SW-846. Method 4010 is an immunoassay 
test for the presence of pentachlorophenol, which determines whether a 
sample is above or below a set limit (such as the 0.1 ppm concentration 
level proposed).
    Under the proposal, if analysis showed that a facility's 
formulation contains pentachlorophenate at levels exceeding 0.1 ppm, 
then the wastes generated from surface protection at that facility 
would be F033 wastes and the owner/operator would be subject to 
additional operating requirements proposed as subpart T of parts 264 
and 265. For details on the specific operating requirements, the reader 
should refer to the proposed notice (58 FR 25706).
    A number of the constituents of concern that are present in wastes 
generated from wood surface protection processes which use 
chlorophenolic formulations do not appear on the list of hazardous 
constituents at 40 CFR part 261, appendix VIII. The Agency proposed to 
add six hazardous constituents to appendix VIII: sodium 
pentachlorophenate, potassium pentachlorophenate, the sodium salt of 
2,3,4,6-tetrachlorophenol, the potassium salt of 2,3,4,6-
tetrachlorophenol, octachlorodibenzo-p-dioxin (OCDD) and 
octachlorodibenzofuran (OCDF).
    Sodium and potassium pentachlorophenate are the sodium and 
potassium salts of pentachlorophenol. These salts were proposed for 
addition to appendix VIII of 40 CFR part 261 since, as a result of 
gastric secretions following ingestion, the sodium and potassium salts 
of pentachlorophenol and 2,3,4,6-tetrachlorophenol are readily 
converted to the corresponding phenols by acidification. Therefore, the 
sodium and potassium salts are reasonably expected to elicit the same 
health effects as the corresponding phenols. For this reason, the 
Agency proposed to add these four compounds to the list of hazardous 
constituents in appendix VIII of 40 CFR part 261.
    The Agency also requested comment on an option not to list as 
hazardous wastes generated from surface protection processes. The 
Agency included the so-called ``no-list'' option in the proposal 
because the future generation of chlorophenolic wastes is expected to 
diminish rapidly to zero and because the results of risk analyses show 
that the risks from the dominant exposure pathways are relatively 
modest, assuming the widespread use of chlorophenolic formulations does 
not resume. The Agency believed at the time of the proposal that 
reintroduction of chlorophenolic formulations into the market place in 
the future was not likely to occur. EPA also noted that the Agency 
would always have the option of reconsidering the listing determination 
should chlorophenolic surface protection formulations be reintroduced 
in the future.

IV. Summary of Public Comments and Responses

    Comments received on the proposed rule are placed under two 
separate headings for purposes of this summary. The first addresses the 
more general comments associated with the proposal, including those 
relating to: (1) General implementation issues of a listing for wastes 
generated by the wood surface protection industry; (2) technical 
approaches discussed in the proposal relating to data sampling 
methodologies; and (3) various engineering assumptions on which the 
proposed listing was based. The second part of this section describes 
the Agency's response to comments dealing with the risk assessment 
methodology used to support the listing determination for these wastes.

A. General Comments

    Several comments were submitted on the proposed listing of F033 
wastes. Four commenters supported the listing in general and two 
commenters supported the concentration-based approach in particular. 
Three commenters opposed the proposed listing and urged EPA to rely on 
its authority under FIFRA to control the risks posed by chlorophenolic 
formulations. One commenter supported an outright ban on the use of 
chlorophenolics for wood surface treatment.
    Two commenters warned that listing F033 wastes would hinder 
remediation efforts at contaminated wood surface protection sites. The 
Agency agrees with the commenters' point that a hazardous waste listing 
may provide a disincentive for owner/operators of surface protection 
plants to initiate voluntary remediation efforts. The regulation of 
potentially large amounts of contaminated soil as listed hazardous 
waste could delay the start of cleanup due to the administrative and 
economic realities of regulatory compliance.
    Three commenters expressed concern over the possibly perceived 
interchangeability of the proposed 0.1 ppm concentration level and the 
Toxicity Characteristic (TC) regulatory level for pentachlorophenol. 
Although the Agency is not finalizing the F033 hazardous waste listing, 
EPA nevertheless wants to make clear that the concentration level 
proposed in the F033 listing description was not intended as a 
regulatory level for any purpose other than defining a waste as F033. 
The current regulatory level for pentachlorophenol that defines a waste 
as hazardous under the TC (100 mg/L) would not have been affected by 
this rulemaking in any way had the F033 listing been promulgated today. 
Levels set for the TC are obtained by running models which simulate 
acidic landfill conditions. For the proposed listing, the proposed 0.1 
ppm level was calculated using a Maximum Contaminant Level (MCL) of 
0.001 ppm and a risk analysis using the Agency's Multi-med model. 
Multi-med simulates groundwater contamination from specific sources, 
and for this proposal, it incorporated variables which are specific to 
sawmill conditions. The Agency's analysis approximated the dilution of 
pentachlorophenate from the time the waste contacts the ground to when 
it reaches a ground water well. The Agency did not arrive at the 0.1 
ppm level by applying a dilution attenuation factor (DAF) of 100 (as 
the Agency has done in other circumstances) to the MCL. Indeed, the 
Agency did not take a position in the proposal about the use of DAFs in 
calculating acceptable risk levels for any constituents. A detailed 
discussion of the Agency's modeling assumptions and actual parameters 
used to generate risk approximations can be found in the docket for the 
proposed rule.
    One commenter expressed reservations regarding the decontamination 
procedures promulgated previously for wood preserving equipment (55 FR 
50482-50483, December 6, 1990). The Agency is aware that equipment 
cleaning will not always prevent cross-contamination. However, it will 
certainly reduce the amount of contamination that would occur if no 
equipment cleaning took place. Although the Agency is not finalizing 
the proposed F033 hazardous waste listing, EPA encourages owner/
operators of surface protection plants to clean or replace any surface-
treating equipment that was used previously with chlorophenolic 
formulations upon a switch to non-chlorophenolic chemicals and properly 
dispose of the wastes in an environmentally sound manner. Furthermore, 
the Agency has obtained information which shows that some new 
substitute products are more effective if residual chlorophenolic 
contamination is removed. Hence, removing sludge and cleaning equipment 
from previous chlorophenolic use will not only be more environmentally 
sound, but may also enhance the new products effectiveness. Methodology 
on recommended cleaning and operating practices for surface protectors 
will be published in the near future by the Agency in a pollution 
prevention and waste minimization guidance document.
    One commenter suggested that the proposed operating standards for 
surface protection plants be codified in part 262 as opposed to parts 
264/265. The commenter reasoned that most surface protection plants are 
only generators and do not function as treatment, storage, and disposal 
facilities (TSDFs). However, since the F033 hazardous waste listing is 
not being promulgated, this issue is moot and there is no need for 
special generator requirements.
    Several commenters had specific concerns about the applicability of 
the proposed F033 listing. Since the Agency is not finalizing the 
proposed F033 listing, these concerns are also moot. However, where 
appropriate, answers specific to each of these comments have been 
addressed in the background document of this final rule.
    One commenter questioned the representativeness of the Agency's 
data on cross-contamination. The commenter stated that because sites 
were not randomly selected, there is no true sample representation of 
the surface protector population. EPA did not choose sampling sites 
based on their statistical representativeness. Rather, the sites were 
selected as appropriate from what the Agency considered to be typical 
operating plants. The Agency visited more than 15 surface protection 
sites in the Nation (both large and small plants). From the information 
obtained from these plant tours and interviews, the Agency developed a 
view of what it considered typical from an engineering standpoint (e.g. 
size of equipment, production scale, presence of containment systems, 
size of storage yards, amount of drippage, etc). The sites sampled need 
not represent the entire surface protection industry in terms of the 
process used and the degree of cross-contamination present to allow the 
Agency to demonstrate that wastes from current and previous use of 
chlorophenolics at surface protection sites were contaminated with the 
constituents of concern. These sites were chosen from information 
obtained by a questionnaire sent out under the Agency's 3007 RCRA 
authority.

B. Comments Regarding Risk Assessment

    Five commenters responded to the risk assessment presented in the 
proposed rule. One commenter stated that the EPA incorrectly converted 
units of measurement in the record sampling data used for the risk 
assessment causing the overestimation of incremental risk for the fish/
shellfish consumption and soil ingestion pathways by a 1,000-fold. The 
EPA agrees with the commenter. The dioxin concentrations in the 
formulation at one of the affected facilities (Aquasco, MD) were 
reported in the wrong units, causing a 1,000-fold error to be 
incorporated into the risk estimates for the fish and shellfish 
ingestion and soil ingestion scenarios. When this error is corrected, 
the TCDD-TEQ dioxin levels used as the source concentration (the 
concentration of formulation dripping onto the ground) for affected 
facilities (cross-contamination from past use of chlorophenolic 
formulations) and used in the lifetime individual risk estimates for 
the soil ingestion scenario and fish and shellfish ingestion scenario 
were reduced by a 1,000-fold. The lifetime individual risk values using 
the corrected data are presented in Table 1. 

  Table 1.--Individual Risk From Cross-Contamination From Past Usage of 
      Chlorophenolic Formulations From Fish and Shellfish Ingestion     
------------------------------------------------------------------------
                           Recreational fishers     General population  
                         -----------------------------------------------
       Population           Central                 Central             
                           tendency    High end    tendency    High end 
------------------------------------------------------------------------
Constituent:                                                            
    2,3,4,7,8-TCDD        2E-12       3E-11       8E-13       1E-11     
     TEQ\1\.                                                            
------------------------------------------------------------------------
\1\Excess lifetime cancer risk.                                         

    The estimated risk to any one individual using the corrected values 
are 1,000-fold lower than the risk estimated in the proposed rule from 
cross-contamination due to past use. In this case for the typically 
exposed individual in the general population, the incremental risk of 
developing cancer is a chance of 0.8 in a trillion (8E-13); in the 
recreational fisher person, the risk of developing cancer is increased 
by only 2E-12. The estimated incremental population risk is also 
reduced, after correction, approximately by a 1,000-fold, to 0.0002 
cases/70 years for the anticipated increase in the development of 
cancer as a result of exposure to ingestion of fish/shellfish 
contaminated with wastes from the use of chlorophenolic formulations 
for wood surface protection. Chart 1 in Section V Part A of this final 
rule shows the original values reported in the April 27, 1993 proposed 
notice.
    The soil ingestion scenarios also were based on the storage yard 
soil concentrations. The soil ingestion scenario assumed that children 
ages 1 to 6 could come into contact with the contaminated soil at the 
sawmill sites because sawmill sites could be converted to rural 
residential land use and the child's play area could be located on the 
area previously used as a storage yard area. The lifetime individual 
risks, using the corrected formulation concentration values for dioxin, 
associated with the soil ingestion scenario for cross-contamination 
from past users of chlorophenolic formulations are presented in Table 
2. 

  Table 2.--Individual Risk From Cross-Contamination From Past Usage of 
         Chlorophenolic Formulations From Direct Soil Ingestion         
------------------------------------------------------------------------
                                                    Storage yard        
                                           -----------------------------
                  Source                       Central                  
                                               tendency       High end  
------------------------------------------------------------------------
Constituent:                                                            
    2,3,7,8-TCDD TEQ\1\...................  7E-10          2E-9         
------------------------------------------------------------------------
\1\Upper bound excess lifetime cancer risk.                             

The estimates presented in Table 2 show that the incremental risks from 
direct soil ingestion by children are below what the Agency considers a 
level of concern. A child exposed to storage yard soils cross-
contaminated by past users of chlorophenolics under typical conditions 
(consumption of 0.1 gram of soil/day for 160 days/year for six years) 
would be subject to an increased cancer risk of 7E-10 over a lifetime, 
or a chance of 0.7 in a billion. The estimated incremental population 
risk is also reduced approximately 1,000-fold (to 4E-7 cases per year 
over a 70-year period) for the anticipated increase in the development 
of cancer as a result of exposure to direct ingestion of soil 
contaminated with wastes from the use of cross-contaminated 
formulations for wood surface protection.
    One commenter remarked that the EPA failed to specifically address 
the incremental risks to subsistence fisher persons from consumption of 
fish/shellfish contaminated from the use of chlorophenolic formulations 
for wood surface protection. EPA agrees that the risks to highly 
exposed sub-populations should be considered. The fish ingestion 
scenarios developed for the proposed rule considered exposure to a 
general population and recreational fisher at the outflow of a drainage 
area containing surface protection facilities.
    EPA used the analysis for the high end recreational fisher to 
approximate the risk to the subsistence fisher. Recent data show that 
the high end ingestion rate for a subsistence fisher is greater than 
for a recreational fisher by a factor of approximately 2. Therefore, 
the incremental risk for a subsistence fisher would not exceed a level 
of concern, since the projected risk to recreational fishers is much 
less than 10-6.
    The analysis of risks from fish consumption assumes that all fish 
in the drainage basin are contaminated. The estimates of PCDDs and 
PCDFs in fish tissue are based on sediment concentrations of these 
constituents. The sediment concentrations are estimated based on the 
erosion of contaminated soils from sawmill sites in a river or stream 
basin and subsequent dilution of contaminant levels by the erosion of 
uncontaminated soils from the corresponding drainage basin.
    The projected risk levels increase as the size of the drainage area 
decreases, due to the relatively lower amounts of uncontaminated soil 
in smaller drainage basins. EPA performed an analysis which shows that, 
even with all exposure parameters set at values which would maximize 
the overall estimate of exposure, in order to reach a risk level of 
10-6, the drainage area would need to be 8,000 hectares or less, 
which is smaller than the smallest drainage area in the country. The 
average drainage area is 440,000 hectares, and the lower fifth 
percentile of the size distribution is 109,000 hectares.
    With regard to the fish/shellfish ingestion scenario, one commenter 
maintained that the fish/shellfish ingestion scenario should have been 
performed on a site-specific basis (i.e. EPA should have used 
parameters seen at individual sites), because not all sawmills are 
located on streams with commercial fisheries. The EPA chose the fish/
shellfish ingestion scenario to be protective of the recreational 
fisher persons and the general population. The risk analysis was 
structured so that the hydrologic cataloguing unit (or watershed) was 
the basic unit of analysis to ensure that the contaminated sediment 
would be associated with a body of water large enough to support fish 
hatcheries and recreational fisher persons. When these assumptions were 
used in the fish/shellfish ingestion scenario using corrected values 
for dioxin found in formulation for PCDDs and PCDFs, the incremental 
risk to individuals with high-end exposures remains well below 
1 x 10-6.
    With regard to the Universal Soil Loss Equation (USLE), one 
commenter asserted that the equation is overly conservative for 
estimating soil erosion from surface protection sites. This equation 
models the amount of soil which is dumped into a drainage area 
containing fish. For a more detailed description of the model, the 
reader is referred to background document of the proposed rule. The EPA 
believes that, although this may be a conservative approach, it is the 
best method currently available. It has been used to support other EPA 
rulemakings and guidance documents. The most notable example being the 
Assessment of Risks from Exposure of Humans, Terrestrial and Avian 
Wildlife, and Aquatic Life to Dioxins and Furans, from Disposal and Use 
of Sludge from Bleached Kraft and Sulfite Pulp and Paper Mills.\1\ Even 
using these conservative assumptions, the incremental risks from cross- 
contamination at these sites are not at a level of concern.
---------------------------------------------------------------------------

    \1\Environmental Protection Agency, 1990. Assessment of Risks 
from Exposure of Humans, Terrestrial and Avian Wildlife to Dioxins 
and Furans, from Disposal and Use of Sludge from Bleached Kraft and 
Sulfite Pulp and Paper Mills. Prepared for the Office of Toxic 
Substances. Washington, DC by Abt Association, Inc. under contract 
nos. 68-02-4283, Task 3-02, and 68-D9-0169, Task 1-15. EPA 560/5-90-
13. July, 1990.
---------------------------------------------------------------------------

    One commenter suggested that the population risks attributable to 
the contaminated fish/shellfish ingestion scenario were too high 
because the entire U.S. population was considered to be exposed. EPA 
disagrees and believes it is appropriate to consider the consumption 
rate of the entire population in estimating risk to the general 
population from this exposure pathway. However, an adjustment of 0.4 
was made to the diet fraction to account for the fact that not all fish 
are contaminated. Thus, only some percentage of the population would be 
affected by the contaminated fish. As discussed in the Risk Assessment 
Background Document for the proposed rule, the 0.4 diet fraction was 
derived by estimating the percentage of rivers and streams (i.e., 
cataloguing units) that have at least one sawmill. A second adjustment 
was made in the calculation of population risk to account for the 
percentage of sawmills that operate surface protection processes (about 
30% of the entire number of sawmills nationally). Population risk for 
the fish/shellfish ingestion scenario has been recalculated for the 
final rule using the corrected incremental storage yard soil TCDD-TEQ 
concentrations. The corrected estimate of incremental population risk 
from cross-contamination is three orders of magnitude lower than the 
risk originally stated in the proposed rule. The corrected number of 
cancer cases expected in 70 years is now 0.0002.
    One commenter asserted that the soil ingestion scenario was overly 
conservative because all of the soil consumption was attributed to 
contaminated storage yard soil and no consumption of ``indoor dust'' 
was considered. EPA considered only the consumption of storage yard 
soil in order to be protective of human health. The range of soil 
ingestion rates for average children aged 1 through 6 is presented in 
the EPA's Exposure Factors Handbook (1990) as 0.2 to 0.8 grams per day. 
These estimated values were determined from the clay content of fecal 
samples taken from children in this age group and thus represent 
consumption of soil. However, the percent of this consumption that is 
attributed to house dust is unknown, as is the contaminant 
concentration in the house dust. The EPA has recalculated the soil 
ingestion scenario using the corrected incremental TCDD-TEQ 
concentrations obtained from the formulation sample. The incremental 
risk estimated is below 1E-6, using the conservative assumptions. The 
Agency's risk levels are particularly protective with the use of these 
conservative assumptions, thereby further lending support to the 
Agency's decision not to list these wastes.
    One commenter stated that children are unlikely to consume sediment 
at the same rate that they consume soil. The Agency agrees, but notes 
that sediment consumption by children was not considered as an exposure 
pathway in the proposed rule. The Agency does not feel that this 
exposure pathway is a significant one in making a determination whether 
or not to list chlorophenolic wastes since the exposure areas of 
concern are relatively small and any land conversion which could take 
place would most likely require soil testing prior to land development.
    One commenter stated that the assumptions used to estimate the 
exposed population in the soil ingestion population risk scenario 
greatly overestimate the number of exposed children. EPA believes that 
the scenario may be conservative, but not implausible. The scenario 
assumes that all sawmill sites are converted to rural residential land 
use, that the children's play areas are located on the site of the 
former storage yards, and that the homes are resold to new families 
with young children every 25 years. These assumptions include a low 
population density in these areas. It would take only a limited number 
of sites to be converted to suburban housing or to daycare or school 
facilities to cause a substantial increase in the exposed population. 
The incremental population risk estimated using the corrected 
incremental value for the storage yard soil TCDD-TEQ concentration is 
4E-7 cases in 70 years, three orders of magnitude lower than that in 
the proposed rule.
    One commenter maintained that the soil ingestion scenario was 
questionable because Superfund liabilities, state laws, and lender 
requirements make land use changes unlikely without site cleanup 
activities. The EPA agrees that, in some states, land transfers and 
subsequent land use changes would be unlikely to occur without cleanup. 
However, not all states are equally diligent in requiring site 
investigations at the time of property transfer, making the types of 
land use changes described in the soil ingestion scenario plausible. 
Because of this, EPA believes it is entirely appropriate to assess risk 
via the soil ingestion pathway, notwithstanding any risk management 
decisions that may be made at some future time to address the risk.
    Two commenters believed that some of the values used as input 
parameters to the ground-water model (i.e. recharge rate, regional 
conductivity, and average depth to water) were too conservative and 
that more appropriate input parameters should be used in this MULTIMED 
model. One commenter believed that the Agency had used DRASTIC (a name 
given to a modelling program used to evaluate the potential which may 
exist resulting from groundwater pollution) to perform its groundwater 
modeling. First, the EPA did not use the DRASTIC model in this 
rulemaking effort; it used the MULTIMED model developed by the Agency 
to perform groundwater models. The Agency did, however, use some soil 
and hydrogeologic information (on hydrogeologic regions and subregions 
collected by Aller et al. (1988)) which is used when applying the 
DRASTIC model. With regard to the parameters felt by the commenter to 
be too conservative, the EPA supports the values used in the proposed 
rule (58 FR at 25706 of April 27, 1993). This hydrogeologic information 
includes many of the input parameters required to run the MULTIMED 
model, and includes such parameters as depth to water, soil type and 
hydraulic conductivity, net recharge, aquifer hydraulic conductivity. 
The EPA selected hydrogeologic subregions in the northwest and 
southeast United States, excluding subregions where sawmills were not 
likely to be sited (e.g., mountain slopes or flanks). Since the 
parameter value ranges presented in Aller et al. (1988) are based on 
compilations of literature values and expert opinion, the values should 
be viewed as bounding ranges, and are not sufficiently statistically 
rigorous to estimate true means or parameter distributions. For the 
average case, ``typical'' parameter values were obtained by examining 
the ranges of values in Aller et al. (1988) for the selected subregions 
only and selecting values representing the central tendency of the 
reported ranges. Similarly, high-end values were selected to represent 
the high end of the exposure distribution, using the higher end of the 
range of parameter values deemed likely to occur by Aller et al. 
(1988). EPA recognizes that there are limitations to this approach, 
largely associated with the non-statistical nature of the data. The 
Agency believes, however, that this data source is the best available 
at this time for regional and subregional estimates of the 
hydrogeologic properties necessary to estimate exposures through the 
ground-water pathway.
    Two commenters felt that the Agency's use of input parameter values 
used for well location and well intake point were too conservative. EPA 
derived the horizontal distance to wells from the responses reported in 
the RCRA's 3007 Industry Questionnaires. Because information was not 
obtained on the well type or construction, all wells described in the 
questionnaire were assumed to be possible sources of drinking water and 
were assumed to be screened to the top of the aquifer, that is, well 
water was assumed to be drawn off the top of the aquifer where organics 
are assumed to exist in greater concentrations than when water is drawn 
from the middle of the aquifer. These assumptions are consistent with 
similar conservative assumptions used to develop other RCRA 
regulations, such as the Toxicity Characteristic (55 FR 11798, March 
29, 1990).
    Two commenters contended that neither biodegradation or chemical 
degradation rates were considered in the ground-water modeling of 
pentachlorophenol contamination. These commenters submitted studies 
showing that biological and chemical degradation of PCP can occur and 
that adequate biological and chemical degradation rates are available 
or can be estimated from these studies. EPA has reviewed these studies 
and agrees that they do indicate that biological and chemical 
degradation of PCP can occur. The information submitted by the 
commenters are results from laboratory studies, reporting the results 
from controlled experiments. However, EPA does not agree that there is 
sufficient information on unassisted field degradation rates, the 
geochemical factors that affect degradation, or their spatial 
variability from site-to-site or region-to-region to model degradation 
in the field at generic or prototypical sites for regulatory purposes. 
Moreover, the existence of metabolites that would confirm the 
occurrence of biodegradation in the field has not been firmly 
established. Therefore, EPA does not believe the data warrant an 
assumption that biodegradation does occur at significant rates at most 
sites. In addition, the toxicities of potential degradation products 
have not been characterized. Therefore, the EPA does not believe it is 
appropriate to consider these mechanisms in this rulemaking.
    One commenter suggested that it would be more appropriate to 
calculate the average peak concentration of pentachlorophenate in 
groundwater used to reflect a 9-year exposure duration by producing a 
breakthrough curve of annual concentrations at a well using the 
MULTIMED model and calculate a series of 9-year or 10-year moving 
averages. The moving averages would be sorted in descending order and a 
paper plot prepared. A preferred percentile value could then be 
selected as the concentration of concern. EPA believes the current 
method of calculating 10-year time-weighted averages by averaging two 
5-year concentrations (including the maximum concentration and the 
highest adjacent 5-year value calculated from each model run) is an 
appropriate approach for estimating lifetime individual risk and the 
Agency selected this approach to be conservative and protective of 
human health. The 30-year exposure duration scenario uses a time-
weighted 30-year average concentration that includes the maximum 
concentration. Population risk estimates aggregated over 70 years were 
based on a time-weighted 70-year average concentration that includes 
the maximum concentration.
    One commenter believed that the source concentration used by EPA 
for PCP in the ground-water ingestion scenario was too high because PCP 
is no longer in use and, thus, the infiltration to ground water would 
be reduced. The commenter suggested that source reduction also would 
occur from erosion of surface soil containing PCP, before it is leached 
and enters the ground water. EPA addressed the fact that PCP is no 
longer in use at most facilities in its baseline risk estimates in the 
proposed rule, which have been revised in the final rule based on 
comments received to reflect source concentrations and pulse durations 
(estimated time in which pentachlorophenate is expected to be present 
in substitute wood surface protection product from time of changeover) 
more representative of the cross-contamination scenario. While surface 
runoff and erosion may reduce the amount of PCP available for leaching 
to ground water, EPA has assumed, for the purpose of its analysis, that 
any reductions are negligible. The EPA adopted this conservative 
assumption mainly because of lack of data necessary to quantify such a 
loss and its effects on ground-water concentrations. Furthermore, EPA 
does not believe that surface water and erosion will significantly 
reduce source leachate concentrations. As formulation drips onto the 
soil it will rapidly penetrate the soil until the soil is saturated. 
Subsequent rain events may wash off contaminated surface soil, but will 
not erode deeper soil horizons where most of the contaminant mass 
resides. Thus, EPA does not consider this assumption to be overly 
conservative.
    One commenter noted that the results of the ground-water analysis 
were not supported by actual resource damage data. The Agency does not 
expect, nor does it feel that it is needed, that ground water PCP 
concentrations predicted by MULTIMED would agree precisely with the 
resource damage data. The resource damage incidents presented in the 
background document are intended to illustrate that ground-water 
contamination from PCP does occur at sawmill facilities, and are not 
intended as validation points for exposure modeling. Resource damage 
data were obtained from monitoring and other wells that happened to be 
in place at a facility when the sampling was conducted. There are a 
number of possible reasons why sampling data from the resource damage 
incidents may not reflect well-water concentrations predicted by the 
model, in particular the location of the wells with regard to plume 
centerline and ground-water flow direction, and the timing of peak 
plume concentrations at the wells.
    The latter point is especially important because, depending on 
patterns of past PCP use and the well location, the peak concentration 
in the plume may not have reached or may have passed the well(s) 
sampled. In these resource damage cases, sufficient information was not 
available to determine the placement and design of these wells with 
respect to the site's hydrogeology or possible plume locations and 
travel time. Thus, it is not possible to use these data points for 
validation of model results. However, it should be noted that the 
model-estimated ground-water PCP concentrations in the final rule are 
similar to those reported from resource damage incidents. When the 
revised average source concentration was used in the ground-water 
model, the estimated concentrations for PCP in ground water (average = 
0 .005 mg/L; high-end = 288 mg/L) are in a reasonable agreement with 
the values reported in the resource damage accounts (<0.001 to 45 mg/
L).
    One commenter disagreed with the use of MULTIMED in that it was not 
as ``robust'' or well-tested as the Monte Carlo-based EPACML model used 
for the TC rule. Another commenter recommends the use of the Monte 
Carlo approach for all input parameters in the modeling effort. First, 
it is important to note that the MULTIMED ground-water model is the 
same model as used in EPACML except for the manner in which input 
parameters are specified. EPACML can only be run in a probabilistic, 
Monte Carlo mode, while MULTIMED allows Monte Carlo runs as well as for 
individual input parameters to be specified and fixed. The ground-water 
flow and transport model components are the same for MULTIMED and 
EPACML. Second, the Agency did not pursue a probabilistic, Monte Carlo-
based approach when developing input parameters for this modeling 
effort due to the fact that using this sophisticated technique requires 
knowledge and proper specification of input parameter distributions, 
and variable independence or proper specification of joint probability 
parameter distributions. When these requirements cannot be met, the 
Monte Carlo approach will not provide better estimates than a scenario-
based approach.
    EPA has adopted a scenario-based regional modeling approach that 
uses input parameters developed for regions of the U.S. where sawmills 
are more prevalent. In this approach, EPA uses average and high-end 
values for estimating model input parameters on a regional basis 
because information does not exist on the actual means and 
distributions of these parameters for the regions modeled. The Agency 
believes that this approach is an appropriate one and, furthermore, 
that the resulting model estimates bracket or bound the uncertainty 
associated with the model input parameters.
    Two commenters questioned the use of cancer as the endpoint of 
concern for 2,3,7,8-TCDD. EPA disagrees. The cancer endpoint for TCDD 
was selected because it is the most sensitive endpoint for which 
qualitative dose response data are available. 2,3,7,8-TCDD has been 
demonstrated to be a potent carcinogen in animals and has been 
classified as a B2 (potential human) carcinogen. Recently published 
epidemiological studies of occupationally exposed individuals report 
significant increases in cancer mortality. 2,3,7,8-TCDD also has potent 
reproductive and teratogenic endpoints and enough data exist to 
estimate a reference dose (RfD) based on these alternative short-term 
effects. (For a detailed discussion of this information, and for 
references to studies supporting these conclusions, the reader is 
referred to the background document of the proposed rule.) However, if 
health-based levels (HBLs) are calculated using the reproductive effect 
RfD, the exposure level is an order of magnitude higher than the level 
calculated using the carcinogen slope factor (CSF). Thus, if the cancer 
end-point is used as the basis for calculating a permissible exposure 
level, it also will be protective against short-term exposures such as 
those associated with reproductive effects.
    The issue of 2,3,7,8-TCDD toxicity is being reassessed by EPA 
(outside the framework of this rulemaking) and all endpoints are being 
considered. TCDD has been observed to express a wide variety of effects 
including teratogenesis, reproductive effects, and suppression of the 
immune system function in many species. Mechanistic approaches to 
understanding and identifying toxic effects levels are also being 
considered. Until the reassessment process has been completed, the EPA 
will continue to use the current carcinogenicity endpoint CSF value 
that has been accepted as the basis for the MCL.
    Two commenters noted limitations associated with the use of the 
Toxicity Equivalence Factors (TEF's) methodology. They argued that the 
TEF methodology should not be used to justify the addition of appendix 
VIII in the absence of valid toxicological studies that demonstrate 
actual health effects associated with exposure to these compounds. One 
commenter questioned the proposal to add Octachlorodibenzo-p-dioxin 
(OCDD) and Octachlorodibenzofuran (OCDF) to 40 CFR part 261, appendix 
VIII. The commenters stated that neither compound has been shown to 
produce toxic, carcinogenic, mutagenic or teratogenic effects on humans 
or other life forms. The Agency has decided not to add, at this time, 
OCDD and OCDF to appendix VIII of 40 CFR part 261. Although the 
original basis for including these congeners on appendix VIII remains 
valid (details of which can be found in the background document 
supporting this final rulemaking), the Agency is investigating further 
the information submitted by the commenters regarding the effects of 
OCDD and OCDF reported in the Couture, Elwell, and Birnbaum study used 
to support the decisions made in the ``Interim Procedures for 
Estimating Risks Associated with Exposures of Mixtures of Chlorinated 
Dibenzo-p-dioxins and Dibenzofurans and the 1989 Update''. OCDD and 
OCDF are the most prevalent of the PCDD and PCDF congeners accounting 
for approximately 85 percent of the total CDD and CDF present in five 
of the six storage yard soil samples. OCDD has been shown to exhibit 
``dioxin-like'' toxicity in male rats when administered in small doses 
in a sub-chronic toxicity study.\2\ These findings have been confirmed 
by a second sub-chronic study conducted in female rats.\3\ OCDD and 
OCDF have not exhibited toxicity in short term studies; however, acute 
exposure is not the only concern of EPA. The Agency is currently re-
evaluating its original assessment of risks from dioxin. At this point, 
the Agency wishes to conclude its on-going reassessment before adding 
OCDD and OCDF to appendix VIII of 40 CFR part 261.
---------------------------------------------------------------------------

    \2\Couture, L.A., M. R. Elwell, and L. S. Birnbaum. Dioxin-like 
effects observed in male rats following exposure to 
octachlorodibenzo-p-dioxin (OCDD) during a 13-week study. Toxicology 
and Applied Pharmacology, Vol. 93, pp 31-46, 1988.
    \3\Hermelinger, N., N. Poiger, and C. Schlatter. Results of a 9-
month feeding study with OCDD and OCDF in rats, Organohalogen 
Compounds, Vol. 1, 1990, pp. 221-224.
---------------------------------------------------------------------------

    One commenter questioned the conclusion that soil contamination 
presents no risk to wildlife. The EPA recognizes that concentrations 
that are protective of human health may not necessarily always be 
protective of wildlife. However, in view of the relatively small areas 
occupied by sawmills and the low concentration of TCDD-TEQ in storage 
yard soil from cross contamination, the EPA believes the incremental 
risks to wildlife will be below a level of concern.

V. Overview of the Final Rule

    This final rule makes final the Agency's hazardous waste listing 
determination for chlorophenolic wastes generated at wood surface 
protection plants. EPA believes that listing as hazardous 
chlorophenolic wastes from surface protection operations is unnecessary 
for reasons described in Part A of this preamble.
    This document also amends SW-846 (Test Methods For Evaluating Solid 
Waste, Physical/Chemical Methods) by adding Method 4010 (Immunoassay 
Test for the Presence of Pentachlorophenol). This action is discussed 
in Section VI of this preamble.
    This final rule also adds four chemicals to the list of hazardous 
constituents at 40 CFR part 261, appendix VIII. These four chemicals 
are: (1) Sodium pentachlorophenate, (2) potassium pentachlorophenate, 
(3) sodium tetrachlorophenate, and (4) potassium tetrachlorophenate. A 
discussion of this action is found in part C of this section.

A. Basis for the Determination Not To List as Hazardous Wastes From 
Wood Surface Protection Operations

    As discussed in the proposed rule, in making a hazardous waste 
listing determination, the Agency applies a ``weight-of-evidence'' 
approach. In doing this, the Agency examines the risks associated with 
all potential human health and environmental exposure pathways, 
analyzes trends in the current industry, researches past damage 
incidents, as well as other factors found in 40 CFR 261.11.
    Upon reviewing and responding to comments received on the proposed 
rule, the Agency has decided not to list as hazardous wastes from the 
use of chlorophenolic formulations in the wood surface protection 
industry for several reasons.
    First, chlorophenolic formulations are no longer being produced in 
the United States and the Agency believes it is very unlikely they will 
be produced in the future. The only remaining producer of 
chlorophenolics in the U.S., Chapman Chemicals, stopped production in 
January of 1992 and sometime later applied for voluntary cancellation 
of its FIFRA product registration. A notice describing this action was 
published in the Federal Register on June 3, 1992 (57 FR 23401), and a 
final cancellation order was sent to Chapman Chemicals with an 
effective date of September 14, 1992. This cancellation notice applies 
to the following products produced by Chapman Chemicals: Permatox 181, 
10S, and 101, and Mitrol G-ST. Any manufacturer wishing to resume 
production of chlorophenolics would have to obtain a new FIFRA 
registration before these chemicals could be re-introduced and made 
available for use in wood surface protection. Currently, there remains 
only one known user of chlorophenolics in the U.S. out of an estimated 
1000 previous users and the remaining plant's existing stock is 
believed to be very limited. A major element in the decision not to 
list as hazardous chlorophenolic wastes generated from the surface 
protection industry is the fact that use of chlorophenolic formulations 
has ceased. EPA believes it is highly unlikely that a manufacturer will 
seek reregistration for this product for many reasons, including the 
availability of effective substitute products and the potentially high 
financial and administrative burdens imposed by the FIFRA registration 
process. Additional justification to support non-future production is 
the fact that European countries do not want to accept dioxin-
containing wood products which have affected large export mills who 
will not use chlorophenolic formulations in the future in part for this 
reason. Use of chlorophenolics for surface protection has declined 
steadily (even without the influence of RCRA) from over 1,000 users to 
one user over the past decade. Should a new registration of this 
product be sought, EPA will consider this surface protection risk 
analysis for full strength application when determining whether a new 
listing determination under RCRA should be initiated. Currently, the 
Agency is aware of nine available substitute products currently being 
used by surface protectors in place of chlorophenolics. The substitute 
products are for a large part satisfactory to their users (as mentioned 
on various site trips), and the Agency does not feel as though a switch 
back to chlorophenolics is likely.
    A second reason why the Agency has decided not to list these wastes 
is because the risk to human health and the environment from on-going 
operations which previously used chlorophenolics is shown to tail off 
quickly because chlorophenolic concentrations diminish to a near zero 
concentration within a short period of time following switchover to an 
alternate product. The Agency has determined that the use of full-
strength chlorophenolic formulations generates wastes that result in 
unacceptable risk to human health and the environment. As before 
mentioned, should the use of chlorophenolics for surface protection 
applications resume, for any reason, the Agency will most likely re-
evaluate its current position. However, dealing with the current 
situation, there remains only one known user of chlorophenolics with a 
limited supply remaining.
    Although the Agency believes the use of full-strength 
chlorophenolics will be phased out in the very near future, there was 
concern at the time of proposal that there may be unacceptable risks 
posed by the use of substitute products that become cross-contaminated 
from previous chlorophenolic use. Particularly, the proposal cited 
possible ground water risks of 2 x 10-4 for individuals and a 
broad but very low potential exposure risk due to surface run-off 
contributing to dioxin levels in fish. The Agency received several 
comments addressing these potential impacts. In response to these 
comments, the Agency conducted additional ground-water modeling using 
new pulse assumptions developed from commenter-submitted information. 
The Agency developed what it believed to be better pulse assumptions in 
an effort to determine how long pentachlorophenate will be present in 
on-going operations which have switched over from its past use. This 
new data was obtained from performing mass balance iterations using 
typical tank volumes found at both large and small facilities. These 
mathematical calculations showed that cross-contamination from previous 
use of chlorophenolics will be present in a substitute products for 
only two to six years from the time a plant stops using 
chlorophenolics. The Agency found that the highest estimated risk to an 
individual from drinking ground water for nine years at peak 
concentrations in the two- or six-year pulse resulting from cross 
contamination, is significantly diminished and the broad effect on 
dioxin levels in fish is reduced by several orders of magnitude. This 
new analysis shows that the risks associated with cross-contamination 
do not justify a hazardous waste listing to capture cross-contaminated 
wastes. In the proposed rule, EPA addressed the fact that PCP is no 
longer in use at most facilities in its baseline risk estimates, which 
have been revised in the final rule to reflect source concentrations 
and pulse durations more representative of the cross-contamination, 
incremental-risk scenario. Chart 1 below compares the incremental risks 
from cross-contaminated wastes as calculated for the proposed rule to 
the values obtained using the new approach.

                        Chart 1.--Incremental Risks\1\ Due to Cross Contaminated Wastes                         
----------------------------------------------------------------------------------------------------------------
                                             Significant                                                        
                        Constituent        threat pathway   Central tendency      High end       Population risk
----------------------------------------------------------------------------------------------------------------
Proposed in NPRM.  Pentachlorophenate     Ground water....  5 x 10-7........  2 x 10-4........  .005            
                    (assumed 30 year                                                                            
                    pulse).                                                                                     
                   Dioxin fish and        Soil............  18 x 10-10        4 x 10-7, rec     0.2             
                    shellfish                                (general          fisher.                          
                    consumption (general                     population).                                       
                    population and                                                                              
                    recreational fisher).                                                                       
                   Dioxin soil ingestion  Soil............  7 x 10-7........  2 x 10-5........  .0004           
Revised..........  Pentachlorophenate (2  Ground water....  6 x 10-7........  2 x 10-5........  .007            
                    year pulse, for                                                                             
                    large facilities).                                                                          
                   Pentachlorophenate (6  Ground water....  2 x 10-6........  6 x 10-5........  0.02            
                    year pulse, for                                                                             
                    small facilities).                                                                          
                   Dioxin fish &          Soil............  2 x 10-12.......  3 x 10-11.......  NR              
                    shellfish                                                                                   
                    consumption                                                                                 
                    (recreational                                                                               
                    fisher).                                                                                    
                   Dioxin fish &          Soil............  8 x 10-13.......  1 x 10-11.......  .0002           
                    shellfish                                                                                   
                    consumption (general                                                                        
                    pop.).                                                                                      
                   Dioxin soil ingestion  Soil............  7 x 10-10.......  2 x 10-9........  4 x 10-7        
----------------------------------------------------------------------------------------------------------------
\1\Excess lifetime cancer risk.                                                                                 

    As shown in Chart 1, population risk is lower than that presented 
in the proposal for both fish/shellfish consumption and the soil 
ingestion pathway, due to a unit conversion error in expressing dioxin 
concentration. The dioxin concentrations in the formulation at one of 
the affected facilities (Aquasco, MD) were reported using incorrect 
units, causing a 1,000-fold error to be incorporated into the risk 
estimates for the fish and shellfish ingestion and soil ingestion 
scenarios. When this error was corrected, the TCDD-TEQ levels used as 
the source concentration for affected facilities (cross-contamination 
from past use of chlorophenolic formulations) and used in the lifetime 
individual risk estimates for the soil/fish and shellfish ingestion 
scenarios also were reduced 1,000-fold.
    The incremental population risk was revised for the ground-water 
scenario from an original 0.005 value to between 0.007 and 0.02 cancer 
cases. This range of 0.007 to 0.02 cancer cases was obtained because 
two different modelling scenarios were run to generate the extremes of 
this range. One model run used input parameters which would simulate 
decay for a small production plant. The input information was obtained 
from a mass balance iteration which showed that it would take a small 
plant approximately 6 years to decrease cross-contamination levels to 
near zero; likewise, the second model used input parameters for large 
facilities which predicted a two year decline to near zero levels of 
cross-contamination. The details of the mass balance approach and the 
resulting change in population risk can be found in the background 
document for this final rule. The Agency believes that these revised 
risk levels do not warrant a hazardous waste listing.
    Based on the above two main factors (i.e. (1) chlorophenolic 
production stoppage and subsequent chlorophenolic use decline and (2) 
revised risk due to cross contamination), the Agency looked closely at 
any potential environmental benefits that may accrue from a hazardous 
waste listing. Given the market trend, the Agency cannot identify any 
tangible benefits to be gained from listing wastes generated from the 
use of chlorophenolic formulations for wood surface protection. 
Environmental damages caused by previous use of chlorophenolics have 
already occurred. A listing of these wastes cannot mitigate past 
damages nor can it force the clean-up of these damages. Such potential 
jurisdiction exists under current programs. Authority under CERCLA and 
RCRA 3007 exists even if a decision is made not to list as is the case 
for this final rule.
    Damage to the environment of this magnitude from previous use of 
chlorophenolic formulations within this industry are not expected to 
occur in the future unless use of full-strength chlorophenolics 
resumes. Furthermore, sampling data collected at surface protection 
sites indicate that dioxin concentrations in storage yards (the largest 
area of a plant) are below 1 ppb. The heavier contamination that occurs 
in the process area is confined to a small area and likely will not 
migrate off-site to environmental receptors. Therefore, the Agency 
finds that the risks posed by this residual contamination are limited 
and that a hazardous waste listing would likely simply result in these 
limited areas of contamination being left in place and not produce an 
environmental benefit. Thus the effect on past contamination does not 
justify a hazardous waste listing.

B. Operating Requirements for Surface Protection Plants

    Because the Agency is not listing F033 wastes, the operating 
standards for surface protection plants proposed in the April 27, 1993 
notice are not applicable and, thus, are not being finalized. 
Furthermore, surface protection plants are not required to follow any 
specific waste management requirements regarding previous use of 
chlorophenolics as a result of this rule.

C. Addition of Chemicals to Appendix VIII of 40 CFR Part 261

    Although this final rule does not list any wastes from wood surface 
protection processes as hazardous, the Agency believes that certain 
constituents contained in these wastes warrant inclusion in appendix 
VIII of part 261. 40 CFR 261.11 provides that ``[s]ubstances will be 
listed on appendix VIII only if they have been shown in scientific 
studies to have toxic, carcinogenic, mutagenic or teratogenic effects 
on humans or other life forms.'' In the April 27 notice, EPA proposed 
to add six hazardous constituents of concern found in surface 
protection wastes to appendix VIII of 40 CFR part 261. Based on the 
information gathered during this listing investigation, the following 
four are being added to the list: sodium pentachlorophenate, potassium 
pentachlorophenate, the sodium salt of 2,3,4,6-tetrachlorophenol, and 
the potassium salt of 2,3,4,6-tetrachlorophenol. The Agency presented 
information in the proposed rule and supporting background documents on 
the adverse effects of these compounds. For those reasons, EPA is 
finalizing the addition of four of these constituents to appendix VIII 
of part 261. The Agency is not at this time finalizing the addition of 
OCDD and OCDF to Appendix VIII. As mentioned before, the Agency is 
investigating further the information submitted by the commenters 
regarding the effects of OCDD and OCDF reported in the Couture, Elwell, 
and Birnbaum study used to support the decisions made in the ``Interim 
Procedures for Estimating Risks Associated with Exposures of Mixtures 
of Chlorinated Dibenzo-p-dioxins and Dibenzofurans and the 1989 
Update''.

VI. Amendment of SW-846 (Test Methods for Evaluating Solid Waste, 
Physical/Chemical Methods)

    In the notice of proposed rulemaking, the Agency proposed to add 
Method 4010 (Immunoassay Test for the Presence of Pentachlorophenate) 
to the Second and Third Editions of SW-846. The purpose behind this 
proposal was to aid owners/operators of wood surface protection plants 
with the proposed formulation testing requirement.
    With respect to requiring the use of SW-846 methods for testing for 
the presence of pentachlorophenate in wood surface protection ``in-
process'' formulation, the issue is moot since EPA is not listing any 
wood surface protection wastes as hazardous. Nonetheless, EPA believes 
that although no comments were received on Method 4010, Method 4010 is 
an appropriate method, in general, for testing for the presence of 
pentachlorophenate or pentachlorophenol and can, therefore, be used in 
other applications other than for wood surface protection formulation 
testing. The Agency is, therefore, adding Method 4010 to the Third 
Edition of SW-846 as Update IIA. We are not adding Method 4010 to the 
Second Edition of SW-846 since the Third Edition has replaced the 
Second Edition on August 31, 1993 for use in mandatory applications (58 
FR 46040). Method 4010, including its protocol and documentation 
supporting this action can be found in the docket for this rulemaking. 
See the ``For Further Information'' Section in front of this preamble 
for the EPA contact person for further information or with questions on 
Method 4010.

VII. Pollution Prevention and Waste Minimization

    The Agency is preparing a separate guidance manual recommending 
voluntary pollution prevention and waste minimization techniques for 
the lumber industry. Since it has studied the surface protection 
industry in making a listing determination for wastes generated from 
the use of chlorophenolic formulations, EPA has gained a broad 
perspective on the best ways to reduce wastes generated by this wood 
surface protection industry. The ideas gained from the study are 
presented in this manual. Some recommended strategies for pollution 
prevention in the surface protection industry are described in this 
section. Further information can be found in the manual.
    The ultimate goal of pollution prevention is to reduce present and 
future threats to human health and the environment. Pollution 
prevention (also referred to as source reduction) is the use of 
materials, processes, or practices that reduce or eliminate the 
quantity and/or toxicity of wastes at the source of generation. 
Pollution prevention is the first step in a hierarchy of options for 
reducing the generation of waste. The first recommended pollution 
prevention option is to replace chemical treatment with another type of 
treatment to achieve surface protection. One alternate is to dry the 
wood to reduce water content (high water content leads to sapstain). 
The Agency is aware that this option may not be economically viable for 
a smaller mill. If such a system cannot be feasibly employed, it would 
be preferable for a user of chlorophenolic-containing formulations to 
switch to an alternate formulation.
    Other pollution prevention strategies for use within the surface 
protection industry include: (1) Providing local and general 
ventilation within the cutting process area to reduce dust that can 
accumulate on wood; (2) blowing wood with air to reduce the amount of 
sawdust on wood prior to surface protection; and (3) using drainage 
collection devices like gutters on rooftops to keep precipitation away 
from process wastes. The pollution prevention practices described here 
can be critical to reduce the amount of waste generated. Although the 
Agency is not listing these chlorophenolic wood surface protection 
wastes, the pollution prevention practices described in the guidance 
manual are applicable to any waste generating process. For wastes that 
cannot be reduced at the source, generators may consider recycling as 
the next best option.

VIII. Analysis of Potential Costs and Benefits

A. Executive Order Requirements

Executive Order 12866
    Under Executive Order 12866, (58 FR 51735 (October 4, 1993)) the 
Agency must determine whether the regulatory action is ``significant'' 
and therefore subject to OMB review and the requirements of the 
Executive Order. The order defines ``significant regulatory action'' as 
one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or state, local, or tribal governments or 
communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or the rights and obligations of recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    It has been determined that this rule is not a ``significant 
regulatory action'' under the terms of Executive Order 12866 and is 
therefore not subject to OMB review. Nevertheless, the Agency prepared 
an abbreviated RIA or ``Economic Assessment'' (EA) in order to examine 
costs and benefits likely to occur as a result of that action.

B. Description of Costs and Benefits of This Rule

    Because the Agency has decided not to list wastes generated from 
the use of chlorophenolic formulations in surface protection 
operations, no specific action is required under this Rule. Facilities, 
however, may choose to take some remedial action as a result of 
publicity surrounding this action. A detailed analysis of work 
performed is described in the background document for this final rule.

IX. State Authority

    Under section 3006 of RCRA, EPA may authorize qualified States to 
administer and enforce the RCRA program within the State. (See 40 CFR 
part 271 for the standards and requirements for authorization.) 
Following authorization, EPA retains enforcement authority under 
sections 3007, 3008, 3013, and 7003 of RCRA, although authorized States 
have primary enforcement responsibility.
    Before the Hazardous and Solid Waste Amendments of 1984 (HSWA) 
amended RCRA, a State with final authorization administered its 
hazardous waste program entirely in lieu of the Federal program in that 
State. The Federal requirements no longer applied in the authorized 
State, and EPA could not issue permits for any plants located in the 
State with permitting authorization. When new, more stringent Federal 
requirements were promulgated or enacted, the State was obligated to 
enact equivalent authority within specified time frames. New Federal 
requirements did not take effect in an authorized State until the State 
adopted the requirements as State law.
    By contrast, under section 3006(g) of RCRA, 42 U.S.C. 6926(g), new 
requirements and prohibitions imposed by the HSWA take effect in 
authorized States at the same time that they take effect in non-
authorized States. EPA is directed to implement those requirements and 
prohibitions in authorized States, including the issuance of permits, 
until the State is granted authorization to do so. While States must 
still adopt HSWA-related provisions as State law to retain final 
authorization, the Federal HSWA requirements apply in authorized States 
in the interim.
    Although this final rule does not list, as hazardous, 
chlorophenolic wastes from the wood surface protection industry, it 
does add four constituents to appendix VIII of 40 CFR part 261. These 
additions will not be effective in authorized States since the 
requirements are not being imposed pursuant to HSWA. These requirements 
will be effective only in those States that do not have final 
authorization. In authorized States, these requirements will not be 
applicable until the States revise their programs to adopt equivalent 
requirements under State law.
    Section 271.21(e)(2) of EPA's state authorization regulations (40 
CFR part 271) requires that States with final authorization must modify 
their programs to reflect Federal program changes and submit the 
modifications to EPA for approval. The deadline by which the States 
must modify their programs to adopt this proposed regulation, if it is 
adopted as a final rule, will be determined by the date of promulgation 
of a final rule in accordance with Sec.  271.21(e)(2). If the proposal 
is adopted as a final rule, Table 1 at 40 CFR 271.1 will be amended 
accordingly. Once EPA approves the modification, the State requirements 
become RCRA Subtitle C requirements.
    States with authorized RCRA programs already may have regulations 
similar to what is being finalized in this rule. These State 
regulations have not been assessed against the Federal regulations 
being proposed today to determine whether they meet the tests for 
authorization. Thus, a State would not be authorized to implement these 
regulations as RCRA requirements until State program modifications are 
submitted to EPA and approved, pursuant to 40 CFR 271.21. Of course, 
States with existing regulations that are not less stringent than 
current Federal regulations may continue to administer and enforce 
their regulations as a matter of State law.
    It should be noted that authorized States are required to modify 
their programs only when EPA promulgates Federal standards that are 
more stringent or broader in scope than existing Federal standards. 
Section 3009 of RCRA allows States to impose standards more stringent 
than those in the Federal program. For those Federal program changes 
that are less stringent or reduce the scope of the Federal program, 
States are not required to modify their programs. (See 40 CFR 
271.1(i).) This proposed rule, if finalized, is neither less stringent 
than nor a reduction in the scope of the current Federal program and, 
therefore, states would be required to modify their programs to retain 
authorization to implement and enforce these regulations.

X. Regulatory Flexibility Analysis

    This final rule amends the hazardous waste regulations by adding 
four chemicals to appendix VIII of 40 CFR part 261 and amending SW-846 
by adding Method 4010. These are impacts with negligible effects to 
small entities. Therefore, there is no need to consider its impacts on 
small entities by preparing a Regulatory Flexibility Analysis.

XI. Paperwork Reduction Act

    This rule does not contain any information collection requirements 
subject to OMB review under the Paperwork Reduction Act of 1980, 44 
U.S.C. 3501 et seq.

List of Subjects

40 CFR Part 260

    Environmental protection, Administrative practice and procedure, 
Confidential business information, Hazardous waste.

40 CFR Part 261

    Hazardous materials, Waste treatment and disposal, Recycling.

    Dated: December 23, 1993.
Carol M. Browner,
Administrator.
    For the reasons set out in the preamble, chapter I of title 40 of 
the Code of Federal Regulations is amended as follows:

PART 260--HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL

    1. The authority citation for part 260 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6912(a), 6921-6927, 6930, 6934, 6935, 
6937, 6938, 6939, and 6974.

    2. Section 260.11 is amended by revising the ``Test Methods for 
Evaluating Solid Waste, Physical/Chemical Methods'' reference in 
paragraph (a) to read as follows:


Sec. 260.11  References.

    (a) * * *
    ``Test Methods for Evaluating Solid Waste, Physical/Chemical 
Methods,'' EPA Publication SW-846 (Third Edition (November, 1986), as 
amended by Updates I, II and IIA). The Third Edition of SW-846 and 
Updates I, II, and IIA (document number 955-001-00000-1) are available 
from the Superintendent of Documents, U.S. Government Printing Office, 
Washington, DC 20402, (202) 783-3238.
* * * * *

PART 261--IDENTIFICATION AND LISTING OF HAZARDOUS WASTE

    3. The authority citation for part 261 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6912(a), 6921, 6922, and 6938.

    4. Appendix VIII of part 261 is amended by adding the following 
hazardous constituents in alphabetical order by common name to read as 
follows:

Appendix VIII to Part 261--Hazardous Constituents 

------------------------------------------------------------------------
                       Chemical abstracts      Chemical      Hazardous  
     Common name              name          abstracts No.    waste No.  
------------------------------------------------------------------------
                                                                        
                              * * * * * * *                             
Potassium             Pentachlorophenol,    7778736......  None         
 pentachlorophenate.   potassium salt.                                  
                                                                        
                              * * * * * * *                             
Sodium                Pentachlorophenol,    131522.......  None         
 pentachlorophenate.   sodium salt.                                     
                                                                        
                              * * * * * * *                             
2,3,4,6-              same................  53535276.....  None         
 tetrachlorophenol,                                                     
 potassium salt.                                                        
2,3,4,6-              same................  25567559.....  None         
 tetrachlorophenol,                                                     
 sodium salt.                                                           
                                                                        
                              * * * * * * *                             
------------------------------------------------------------------------

* * * * *
[FR Doc. 93-32032 Filed 12-30-93; 8:45 am]
BILLING CODE 6560-50-P