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Announcement of Small System Compliance Technology Lists for Existing National Primary Drinking Water Regulations and Findings Concerning Variance Technologies

 

Federal Register Document



[Federal Register: August 6, 1998 (Volume 63, Number 151)]
[Notices]               
[Page 42032-42048]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr06au98-58]

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ENVIRONMENTAL PROTECTION AGENCY

[FRL-6137-3]

 
Announcement of Small System Compliance Technology Lists for 
Existing National Primary Drinking Water Regulations and Findings 
Concerning Variance Technologies

AGENCY: Environmental Protection Agency.

ACTION: Notice of lists of technologies and upcoming release of 
guidance and supporting documents.

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SUMMARY: The Environmental Protection Agency (EPA) announces the Small 
System Compliance Technology Lists and the upcoming release of three 
guidance documents and three supporting documents. These lists, 
guidance and supporting documents are related to the provisions in the 
Safe Drinking Water Act (SDWA), as amended in 1996. The three guidance 
documents are: EPA-815-R-98-001, Small System Compliance Technology 
List for the Surface Water Treatment Rule and Total Coliform Rule which 
includes an update of the existing document-EPA 815-R-97-002; EPA-815-
R-98-002, Small System Compliance Technology List for the

[[Page 42033]]

Non-Microbial Contaminants Regulated Before 1996; EPA-815-R-98-003, 
Variance Technology Findings for Contaminants Regulated Before 1996. 
The three supporting documents are: National-Level Affordability 
Criteria Under the 1996 Amendments to the Safe Drinking Water Act; An 
Assessment of the Vulnerability of Non-Community Water Systems to SDWA 
Cost Increases; and Cost Evaluation of Small System Compliance Options: 
Point-of-Use and Point-of-Entry Treatment Units.

DATES: The lists of technologies are provided with today's notice. The 
guidance manuals and supporting documents will be released beginning 
September 15, 1998.

ADDRESSES: Please contact the Safe Drinking Water Hotline, at phone: 
(800) 426-4791, fax: (703) 285-1101, or by e-mail at <hotline-
sdwa@epamail.epa.gov> to request copies of the guidance and supporting 
documents beginning September 15, 1998. The guidance documents will 
also be available on the Internet at <www.epa.gov/safewater/> after 
September 15, 1998.

FOR FURTHER INFORMATION CONTACT: For general information about the 
availability of these guidance and supporting documents, please contact 
the Safe Drinking Water Hotline, at phone: (800) 426-4791, fax: (703) 
285-1101. For other 
information on Technologies for Small Drinking Water Systems please 
contact Jeffrey Kempic, Phone: (202) 260-9567, Fax: (202) 260-3762 or 
Tara Cameron, Phone: (202) 260-3702, Fax: (202) 260-3762 at the U.S. 
Environmental Protection Agency.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Background
II. Small System Compliance Technology List for the Surface Water 
Treatment Rule and Total Coliform Rule
III. Small System Compliance Technology List for the Non-Microbial 
Contaminants Regulated Before 1996
IV. Variance Technology Findings for Contaminants Regulated Before 
1996

I. Background

A. Treatment Technologies Under the SDWA

    The National Primary Drinking Water Regulations (NPDWRs) 
promulgated prior to the 1996 SDWA Amendments include both maximum 
contaminant levels (MCLs) and treatment techniques. For the NPDWRs 
where an MCL was promulgated, Section 1412(b)(4)(B) of the SDWA 
required EPA to set the MCL as close to the maximum contaminant level 
goal as is feasible. For the NPDWRs where a treatment technique was 
promulgated, Section 1412(b)(7)(A) of the SDWA specified the conditions 
under which the Administrator can promulgate a treatment technique in 
lieu of an MCL. In those cases, the Administrator must identify those 
treatment techniques which, in the Administrator's judgement, would 
prevent known or anticipated adverse effects on the health of persons 
to the extent feasible. Section 1412(b)(4)(D) of the SDWA states that 
``the term `feasible' means feasible with the use of the best 
technology, treatment techniques and other means which the 
Administrator finds, after examination for efficacy under field 
conditions and not solely under laboratory conditions, are available 
(taking cost into consideration).''
    The cost assessments for the feasibility determinations have 
historically been based upon impacts to regional and large metropolitan 
water systems serving populations greater than 50,000 persons. This 
standard was established when the SDWA was enacted in 1974 [H.R. Rep. 
No. 93-1185 at 118 (1974)] and when the Act was amended in 1986 [132 
Cong. Rec. S6287 (May 21, 1986)]. Since large systems served as the 
basis for the feasibility determinations, the technical and/or cost 
considerations associated with these technologies often made them 
inappropriate or unavailable for small water systems. The 1996 
amendments to the SDWA specifically require EPA to make small system 
technology assessments for both existing and future regulations.

B. Small Systems Options: Compliance and Variance Technologies

    For the evaluation of technologies, the SDWA identifies three 
categories of small systems. The categories are defined in Section 
1412(b)(4)(E)(ii) and are as follows: public water systems serving (1) 
a population of 10,000 or fewer but more than 3,300; (2) a population 
of 3,300 or fewer but more than 500; and (3) a population of 500 or 
fewer but more than 25. The SDWA directs EPA to make technology 
assessments for each of these three size categories in all future 
regulations establishing an MCL or treatment technique. In addition, 
SDWA identifies two classes of technologies for small systems for 
future National Primary Drinking Water Regulations (NPDWRs): compliance 
technologies and variance technologies. A compliance technology may 
refer to both a technology or other means that is affordable and that 
achieves compliance with the maximum contaminant level (MCL) and to a 
technology or other means that satisfies a treatment technique 
requirement. Possible compliance technologies include packaged or 
modular systems and point-of-entry (POE) or point-of-use (POU) 
treatment units [see Section 1412(b)(4)(E)(ii)]. Variance technologies 
are only specified for those system size/source water quality 
combinations for which there are no listed compliance technologies 
[Section 1412(b)(15)(A)]. Thus, the listing of a compliance technology 
for a size category/source water combination prohibits the listing of 
variance technologies for that combination. While variance technologies 
may not achieve compliance with the MCL or treatment technique 
requirement, they must achieve the maximum reduction or inactivation 
efficiency that is affordable considering the size of the system and 
the quality of the source water. Variance technologies must also 
achieve a level of contaminant reduction that is protective of public 
health [Section 1412(b)(15)(B)].
    There are two mandatory lists of compliance technologies that will 
be developed for the existing MCL and treatment technique rules. By 
August 6, 1997, the Administrator was required to list technologies 
that meet the surface water treatment rule (SWTR) for each of the three 
size categories [Section 1412(b)(4)(E)(v)]. This deadline was met and 
the list was published in the Federal Register on August 11, 1997. By 
August 6, 1998, after consultation with the States, the Administrator 
must issue a list of technologies that achieve compliance with the MCLs 
or treatment technique requirements for other existing NPDWRs. By 
August 6, 1998, after consultation with the States, the Administrator 
must issue, if applicable, guidance or regulations for variance 
technologies for the existing NPDWRs for which a small system variance 
can be granted. When variance technologies are listed, EPA must provide 
any assumptions used in determining affordability, taking into 
consideration the number of persons served by such systems [Section 
1412(b)(15)(C)]. Small system variances are not available for all 
contaminants [see Section 1415(e)(6)]. When small system variances are 
not available under the SDWA, variance technologies will not be listed.
    Although the statute is silent concerning whether small system 
compliance technologies for existing regulations should be affordable, 
EPA believes that the better approach under the statute is that 
affordability should be evaluated for future regulations and

[[Page 42034]]

existing regulations where the statute allows variance technologies. If 
the candidate technologies are not evaluated against an affordable 
technology criterion, then compliance technologies would exist for all 
of the existing regulations regardless of the source water quality. The 
existing best available technologies (BATs) or treatment techniques 
would become the compliance technologies for small systems, which was 
the case prior to the 1996 Amendments. EPA does not believe that result 
to be what Congress intended. As a result, EPA will evaluate small 
system technologies against an affordable technology criterion for 
those existing regulations where small system variances or variance 
technologies are not prohibited by the SDWA. When affordable compliance 
technologies are identified for these contaminants, technologies that 
can achieve compliance but did not meet the affordability criterion 
will also be identified. This is consistent with EPA's approach to the 
compliance technology list for the SWTR and the views of stakeholders. 
EPA will list these technologies and indicate that they did not pass 
the affordable technology criterion rather than limit the information 
on options available to systems. For those regulations where the SDWA 
prohibits small system variances or variance technologies, 
affordability will not be considered in the evaluation of compliance 
technologies because there would be no function to doing so (all 
systems subject to the rule must comply).
    All of the 80 currently regulated contaminants were considered in 
forming the compliance technology lists. Compliance technologies have 
not been listed for aldicarb, aldicarb sulfoxide, aldicarb sulfone, and 
nickel since the NPDWRs for these contaminants are not in effect. All 
of the 80 currently regulated contaminants either have affordable 
compliance technologies or are not eligible for variance technologies 
because of prohibitions in the SDWA. Thus, there are no variance 
technologies listed for the currently regulated contaminants in this 
listing. The rationale for not listing any variance technologies is 
described in Section IV. Section IV also contains a discussion on EPA's 
perspective regarding future revisions to these listings.
    The SDWA, as amended, does not specify the format for the 
compliance technology lists. Section 1412(b)(15)(D) does state that the 
variance technology lists can be issued either through guidance or 
regulations. Moreover, the lists provided in today's notice are 
informational and interpretive and do not require changes to the 
associated National Primary Drinking Water Regulations. Thus, EPA 
believes the compliance technology lists issued today are appropriately 
provided through this notice and the referenced guidance documents 
rather than through rulemaking.

C. Small System Compliance Technology Lists and Product-Specificity

    The small system compliance lists will not be product-specific 
since EPA's Office of Ground Water and Drinking Water does not have the 
resources to review each product for each potential application, nor 
does EPA feel it would be appropriate to do so. However, information on 
specific products may soon be available through another mechanism. The 
EPA Office of Research and Development has a pilot project under the 
Environmental Technology Verification (ETV) Program to provide 
technology purchasers with performance data generated by independent 
third parties. The EPA and National Sanitation Foundation (NSF) 
International are cooperatively organizing and conducting this pilot 
project in part to address the needs of community water systems for 
verification testing of packaged drinking water treatment systems. The 
ETV pilot project includes development of verification protocols and 
test plans, independent testing and validation of packaged equipment, 
government/industry partnerships to obtain credible cost and 
performance data, and preparation of product verification reports for 
wide-spread dissemination.

II. Update to the Small System Compliance Technology List for the 
Surface Water Treatment Rule and Total Coliform Rule

A. Small System Compliance Technology List for the Surface Water 
Treatment Rule (SWTR)

A1. Overview
    The Small System Compliance Technology List for the SWTR was 
published in the Federal Register on August 11, 1997 (62 Fed. Reg., 
42987). The August 1997 notice announced that the SWTR list would be 
updated in 1998. This notice provides this update to the SWTR list and 
announces the upcoming release of the updated supporting guidance 
document.
A2. Description of Updated SWTR List
    This update contains information on applicability ranges and other 
issues that a water system should consider prior to selecting a 
disinfection or filtration technology. The level of detail that is 
provided concerning these factors was discussed at a public meeting 
concerning technologies for small drinking water systems held on May 18 
and 19, 1998 in Washington, D.C. Additional information that is 
incorporated into this list of compliance technologies includes: (1) 
influent water quality range and considerations; (2) an evaluation of 
microbial (Giardia and viruses) log removal credits for technologies 
not originally listed in the SWTR; and (3) additional technical 
limitations. The guidance manual contains information on operation and 
maintenance requirements, waste disposal, potential disinfection by-
products and other technical concerns related to finished water 
quality.
    EPA has revised the listing for one of the disinfection 
technologies on the 1997 list. EPA has recharacterized ``mixed oxidant 
disinfection'' as ``on-site oxidant generation'' in the 1998 compliance 
technology list for the SWTR. In this process, an electric current is 
passed through a continuous-flow brine (salt) solution within a cell. 
After dilution, the electrolyzed brine solution containing the 
concentrated disinfectant is injected into the water for treatment. 
Recent research has not determined that additional oxidants other than 
free chlorine are produced to a significant degree by this process. The 
guidance manual contains additional detail on the recharacterization of 
this technology.
    EPA also evaluated several new or ``emerging'' disinfection and 
filtration technologies that merit consideration for small system 
application. The disinfection technologies that were evaluated were: 
advanced oxidation or ``perozone'' (the combined use of ozone and 
hydrogen peroxide), pulsed ultraviolet radiation (UV), and ultraviolet 
oxidation (the combined use of UV and chemical oxidants). EPA has 
determined that these technologies should still be classified as 
``emerging technologies'' due to (1) lack of data on microorganism 
inactivation rates and (2) insufficient data regarding their 
performance in small systems. EPA will further evaluate these 
technologies as information becomes available for possible inclusion in 
a future update to the compliance technology list for the SWTR. The 
guidance manual contains a more detailed discussion of the data needs 
for these technologies. Backwashable depth filters was the one form of 
filtration technology that was evaluated. Backwashable depth filters 
were found viable for small systems and

[[Page 42035]]

were added to the compliance technology list for the SWTR.
    EPA is not listing point-of-use (POU) and point-of-entry (POE) 
devices as compliance technologies for the SWTR. The 1996 SDWA 
specifically prohibits POU devices as compliance technologies for 
microbial contaminants [Section 1412(b)(4)(E)(ii)]. While POE devices 
are not prohibited, there are several difficulties that would need to 
be overcome and questions answered before POE devices could be 
considered as viable treatment options for microbial contaminants. For 
instance, how would disinfection be applied? The National Research 
Council, a principal operating agency of the National Academy of 
Sciences, advises that POE devices not be used for disinfection 
purposes since ``control of acute disease should be accomplished with 
the highest feasible degree of competence.'' (National Research 
Council. Safe Water From Every Tap: Improving Water Service to Small 
Communities. National Academy Press. Washington, D.C. 1997.) Since 
disinfection following filtration is considered good engineering 
practice, the absence of disinfection following POE filtration devices 
presents an obstacle to the use of these devices for these purposes. 
Finally, if POE devices were used in spite of such considerations, what 
would be the required monitoring frequency? Since microbial 
contaminants pose potential acute health threats, monitoring 
requirements would necessarily be extensive. In light of this 
difficulty, monitoring requirements alone may make POE devices 
inapplicable as small systems technologies for SWTR compliance.
    Future lists may be expanded to include additional technologies as 
current performance informational deficiencies are addressed. The SWTR 
small system compliance technology list will continue to evolve over 
time as updates are published.

B. Compliance Technologies for the Total Coliform Rule (TCR)

    EPA promulgated the TCR in June 1989. The TCR contains a listing of 
``best technologies, treatment techniques, or other means available for 
achieving compliance with the maximum contaminant level (MCL) for total 
coliforms'' [40 CFR Sec. 141.63 (d)]. At the time these techniques were 
codified, no specific notation as to applicability to categories of 
public water system size was included. However, as discussed above, 
with passage of the Safe Drinking Water Act Amendments of 1996, EPA is 
to specify compliance technologies for three small water system size 
categories, defined by the Act as those serving 10,000-3,301 persons; 
3,300-501 persons; and 500-25 persons.
    EPA presented stakeholders with a proposed TCR compliance 
technology list at the May 1998 meeting. This proposed listing was 
essentially the same as the means of compliance listed in the final 
TCR. EPA has received no substantive comments on the listing or 
technical information that would warrant a substantive change to the 
means of compliance specified in 1989. Therefore, the Agency is listing 
the same treatment techniques and other means for small systems 
compliance as were codified in the 1989 rule. Under SDWA, variances are 
not allowed for regulations that control microbiological contamination; 
thus there are no variance technologies for this rule.

C. Availability of a Guidance Document Regarding This List

    This list is supported by the updated guidance document entitled 
``Small System Compliance Technology List for the Surface Water 
Treatment Rule and Total Coliform Rule'' that will be released on 
September 15, 1998. The guidance document is organized into several 
chapters describing the listed small system compliance technologies for 
the SWTR and TCR. Chapter 1 discusses the requirements of the 1996 
amendments to the SDWA and the approach EPA followed to meet those 
requirements. Chapter 2 discusses the list of technologies that were 
evaluated for the compliance technology list. Chapter 3 discusses the 
compliance technologies for the Total Coliform Rule. Chapter 4 
discusses emerging technologies and issues for further considerations.

D. May 18-19, 1998 Stakeholder Meeting

    EPA held a stakeholder meeting on May 18 and 19, 1998. The meeting 
took place at RESOLVE, 1255 23rd Street, N.W., Washington, D.C. 
Approximately 50 people registered and participated at the meeting. 
Stakeholders included representatives from public water utilities, 
state regulatory agencies, public interest groups, the public health 
community, research community, equipment manufacturers and other 
related industries. At the meeting, EPA presented the proposed draft 
1998 listings for the SWTR and TCR to stakeholders. The main 
discussions centered on EPA's tabulations of listed and ``emerging'' 
technologies for the SWTR, and to a lesser extent on TCR technologies. 
The tables provided detailed information as researched by EPA on the 
following subject areas: treatment efficacy, including ranges of 
microbial inactivation; treatment complexity and operator skill levels 
required; byproducts formed (both chemical and physical byproducts of 
treatment); raw water quality concerns; and other important limitations 
of the listed treatments. Stakeholder discussions were fruitful and 
resulted in several proposed changes to EPA's draft listing. Proposed 
changes included the following:
    <bullet> Stakeholders suggested that EPA group several of the 
``emerging'' technologies into the ``advanced oxidation'' heading; and, 
that modifications to traditional ultraviolet radiation be grouped 
together as ``advanced ultraviolet'' treatment.
    <bullet> Stakeholders generally agreed with EPA that the above-
referenced advanced treatments should still be considered ``emerging'' 
due to some gaps in information, such as the lack of availability of 
treatment efficacy data and/or operational data in a small systems or 
drinking water setting. It was also noted that the above-cited EPA/NSF 
verification program may provide results on the testing of some of the 
disinfection technologies later in the year, which may be reviewed 
prior to the next listing for the subject microbial regulations.
    <bullet> EPA was advised to include the caveat that bag filters 
should be handled carefully due to the fragility of the materials, and 
that seals on cartridge filters can be damaged and require special 
attention.
    <bullet> EPA was advised that, in reference to bag and cartridge 
filtration, it would not be advisable to specify maximum raw water 
turbidity levels (i.e., the 2 to 3 nephelometric turbidity units (NTU) 
cited). Such limits may be more a function of pretreatment and system 
economy, and that levels up to 10-30 NTU have been treated 
successfully.
    <bullet> EPA was advised that many U.S. small drinking water 
systems are currently using ozonation for primary disinfection and that 
the International Ozone Association has recently compiled and presented 
operational case study data (a tabulated listing and presentation by R. 
Rice at the May 1998 NSF/WHO/PAHO Small Systems Symposium were provided 
to EPA); however, it is generally believed that ``advanced'' 
combinations involving ozone have yet to be demonstrated for small 
systems and that they may in fact not be practical for small systems. 
Ozone representatives also pointed out that previously cited cleaning 
problems have been largely overcome in the past 5 years due to use of 
pure oxygen feeds

[[Page 42036]]

(in lieu of air feed) in the newer ozone generators.
    <bullet> Many stakeholders have indicated that an annual update to 
the SWTR listing of technologies would be appropriate in order to 
capture any developments in the treatment technology field.
    <bullet> No specific changes or substantive comments were received 
relative to the proposed TCR listing of compliance technologies,.
    This 1998 list and the supporting guidance document reflect the 
input from stakeholders.

E. List of Compliance Technologies for the SWTR and TCR

    The following tables contain the 1998 list of compliance 
technologies for the SWTR and the TCR for the three small system size 
categories. A more detailed description of each technology can be found 
in the guidance document. The three population size categories of small 
public water systems as defined in the SDWA are those serving: 10,000-
3,301 persons, 3,300-501 persons, and 500-25 persons. The technologies 
are listed for all three size categories; however, systems should 
examine the ``Limitations'' column before selecting a technology. This 
column contains information that could limit the applicability of the 
technology for some systems within a size category or categories. Water 
treatment plant operator skill requirements vary with each piece of 
unit technology. The tables for filtration and disinfection 
technologies include a skill level for each technology ranging from 
basic to advanced. For a piece of unit technology that requires ``basic 
operator skill'', an operator with minimal experience in the water 
treatment field can perform the necessary system operation and 
monitoring if provided with written instruction. ``Intermediate 
operator skill'' implies that the operator understands the principles 
of water treatment and has a knowledge of the regulatory framework. 
``Advanced operator skill'' implies that the operator possesses a 
thorough understanding of the principles of system operation, including 
water treatment and regulatory requirements. The ``operator skill level 
required'' column in the tables refers to the skill level needed for 
the unit technology. If pretreatment is required, the required operator 
skill levels will likely increase.
    These lists will be updated in August 1999 if new information 
becomes available. The updated list would include new technologies or 
additional information on existing technologies. A description of each 
technology can be found in the guidance document. The water quality 
issues and technology limitations noted for the technologies in this 
notice are general limitations. The guidance manual contains site-
specific limitations and water quality issues that systems should 
consider before selecting a treatment technology. The guidance manual 
also contains additional information on the by-products produced by the 
disinfection technologies and the waste generated by filtration 
processes.

                            Table 1.--SWTR Compliance Technology Table: Disinfection                            
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                                                                      Raw water quality    Removals: Log Giardia
        Unit technology         Limitations (see   Operator skill         range and          & Log Virus w/CT's 
                                   footnotes)      Level Required       considerations      indicated in () \1\ 
----------------------------------------------------------------------------------------------------------------
Free Chlorine.................  (<SUP>a, <SUP>b)..........  Basic...........  Better with high       3 log (104) & 4 log  
                                                                     quality. High iron     (6).                
                                                                     or manganese may                           
                                                                     require                                    
                                                                     sequestration or                           
                                                                     physical removal.                          
Ozone.........................  (<SUP>c, <SUP>d)..........  Intermediate....  Better with high       3 log (1.43) & 4 log 
                                                                     quality. High iron     (1.0).              
                                                                     or manganese may                           
                                                                     require                                    
                                                                     sequestration or                           
                                                                     physical removal.                          
Chloramines...................  (<SUP>e).............  Intermediate....  Better with high       3 log (1850) & 4 log 
                                                                     quality. Ammonia       (1491).             
                                                                     dose should be                             
                                                                     tempered by natural                        
                                                                     ammonia levels in                          
                                                                     water.                                     
Chlorine Dioxide..............  (<SUP>f).............  Intermediate....  Better with high       3 log (23) & 4 log   
                                                                     quality.               (25).               
On-Site Oxidant Generation....  (<SUP>g).............  Basic...........  Better with high       Research pending on  
                                                                     quality.               CT values. Use free 
                                                                                            chlorine.           
Ultraviolet Radiation.........  (<SUP>h).............  Basic...........  Relatively clean       1 log Giardia (80-   
                                                                     source water           120) & 4 log viruses
                                                                     required. Iron,        (90-140) mWsec/cm2  
                                                                     natural organic        doses in parentheses
                                                                     matter and turbidity   <SUP>2.                  
                                                                     affect UV dose.                            
----------------------------------------------------------------------------------------------------------------
\1\ CT (Concentration x Time), in mg-min/L, based upon 1989 Surface Water Treatment Rule Guidance Manual. Temp. 
  10 C, mid-pH range, unless otherwise indicated.                                                               
\2\ UV dose is product of mW/cm2 (intensity) x sec (time); bases of viral inactivation ranges are rotavirus and 
  MS-2 tests .                                                                                                  
Limitations Footnotes to Table 1: SWTR Compliance Technology Table: Disinfection                                
<SUP>a Providing adequate CT (time /storage) may be a problem for some supplies.                                     
<SUP>b Chlorine gas requires special caution in handling and storage, and operator training.                         
<SUP>c Ozone leaks represent hazard: air monitoring required.                                                        
<SUP>d Ozone used as primary disinfectant (i.e., no residual protection).                                            
<SUP>e Long CT. Requires care in monitoring of ratio of added chlorine to ammonia.                                   
<SUP>f Chlorine dioxide requires special storage and handling precautions.                                           
<SUP>g Oxidants other than chlorine not detected in solution by significant research effort. CT should be based on   
  free chlorine until new research determines appropriate CT values for electrolyzed salt brine.                
<SUP>h No disinfectant residual protection for distributed water.                                                    


                             Table 2.--SWTR Compliance Technology Table: Filtration                             
----------------------------------------------------------------------------------------------------------------
                                                                      Raw water quality                         
        Unit technology         Limitations (see   Operator skill         range and        Removals: Log Giardia
                                   footnotes)      level required       considerations          & Log Virus     
----------------------------------------------------------------------------------------------------------------
Conventional Filtration         (<SUP>a).............  Advanced........  Wide range of water    2-3 log Giardia & 1  
 (includes dual-stage and                                            quality. DAF more      log viruses.        
 dissolved air flotation).                                           applicable for                             
                                                                     removing particulate                       
                                                                     matter that doesn't                        
                                                                     readily settle:                            
                                                                     algae, high color,                         
                                                                     low turbidity (up to                       
                                                                     30-50 NTU) and low-                        
                                                                     density turbidity.                         

[[Page 42037]]

                                                                                                                
Direct Filtration (includes in- (<SUP>a).............  Advanced........  High quality.          0.5 log Giardia & 1-2
 line filtration).                                                   Suggested limits:      log viruses (1.5-2  
                                                                     average turbidity 10   log Giard. w/       
                                                                     NTU; maximum           coagulation).       
                                                                     turbidity 20 NTU; 40                       
                                                                     color units; algae                         
                                                                     on a case-by-case                          
                                                                     basis.\1\.                                 
Slow Sand Filtration..........  (<SUP>b).............  Basic...........  Very high quality or   4 log Giardia & 1-6  
                                                                     pre-treatment. Pre-    log viruses.        
                                                                     treatment required                         
                                                                     if raw water is high                       
                                                                     in turbidity, color,                       
                                                                     and/or algae.                              
Diatomaceous Earth Filtration.  (<SUP>c).............  Intermediate....  Very high quality or   ``Very effective''   
                                                                     pre-treatment. Pre-    for Giardia; low    
                                                                     treatment required     bacteria and virus  
                                                                     if raw water is high   removal.            
                                                                     in turbidity, color,                       
                                                                     and/or algae.                              
Reverse Osmosis...............  (<SUP>d, <SUP>e, <SUP>f).......  Advanced........  Requires pre-          Very effective (cyst 
                                                                     filtrations for        and viruses).       
                                                                     surface water--may                         
                                                                     include removal of                         
                                                                     turbidity, iron, and/                      
                                                                     or manganese.                              
                                                                     Hardness and                               
                                                                     dissolved solids may                       
                                                                     also affect                                
                                                                     performance.                               
Nanofiltration................  (<SUP>e).............  Intermediate....  Very high quality of   Very effective (cyst 
                                                                     pre-treatment. See     and viruses).       
                                                                     reverse osmosis pre-                       
                                                                     treatment.                                 
Ultrafiltration...............  (<SUP>g).............  Basic...........  High quality or pre-   Very effective       
                                                                     treatment.             Giardia, >5-6.      
Microfiltration...............  (<SUP>g).............  Basic...........  High quality or pre-   Very effective       
                                                                     treatment required.    Giardia, >5-6 log;  
                                                                                            Partial removal     
                                                                                            viruses.            
Bag Filtration................  (<SUP>g, <SUP>h, <SUP>i).......  Basic...........  Very high quality or   Variable Giardia     
                                                                     pre-treatment          removals &          
                                                                     required, due to low   Disinfection        
                                                                     particulate loading    required for virus  
                                                                     capacity. Pre-         credit.             
                                                                     treatment if high                          
                                                                     turbidity or algae.                        
Cartridge Filtration..........  (<SUP>g, <SUP>h, <SUP>i).......  Basic...........  Very high quality or   Variable Giardia     
                                                                     pre-treatment          removals &          
                                                                     required, due to low   Disinfection        
                                                                     particulate loading    required for virus  
                                                                     capacity. Pre-         credit.             
                                                                     treatment if high                          
                                                                     turbidity or algae.                        
Backwashable Depth              (<SUP>g, <SUP>h, <SUP>i).......  Basic...........  Very high quality or   Variable Giardia     
 Filtration.\3\.                                                     pre-treatment          removals &          
                                                                     required, due to low   Disinfection        
                                                                     particulate loading    required for virus  
                                                                     capacity. Pre-         credit.             
                                                                     treatment if high                          
                                                                     turbidity or algae.                        
----------------------------------------------------------------------------------------------------------------
\1\ National Research Council, Committee on Small Water Supply Systems. ``Safe Water From Every Tap: Improving  
  Water Service to Small Communities.'' National Academy Press, Washington, D.C. 1997.                          
\2\ Adham, S.S., Jacangelo, J.G., and Laine, J.M. ``Characteristics and Costs of MF and UF Plants.'' Journal    
  American Water Works Association, May 1996.                                                                   
\3\ New technology added by this notice.                                                                        
Limitations Footnotes to Table 2: SWTR Compliance Technology Table: Filtration                                  
<SUP>a Involves coagulation. Coagulation chemistry requires advanced operator skill and extensive monitoring. A      
  system needs to have direct full-time access or full-time remote access to a skilled operator to use this     
  technology properly.                                                                                          
<SUP>b Water service interruptions can occur during the periodic filter-to-waste cycle, which can last from six hours
  to two weeks.                                                                                                 
<SUP>c Filter cake should be discarded if filtration is interrupted. For this reason, intermittent use is not        
  practical. Recycling the filtered water can remove this potential problem.                                    
<SUP>d Blending (combining treated water with untreated raw water) cannot be practiced at risk of increasing         
  microbial concentrations in finished water.                                                                   
<SUP>e Post-disinfection recommended as a safety measure and for residual maintenance.                               
<SUP>f Post-treatment corrosion control will be needed prior to distribution.                                        
<SUP>g Disinfection required for viral inactivation.                                                                 
<SUP>h Site-specific pilot testing prior to installation likely to be needed to ensure adequate performance.         
<SUP>i Technologies may be more applicable to system serving fewer than 3,300 people.                                


    Table 3.--Compliance Technology Table for the Total Coliform Rule   
------------------------------------------------------------------------
     40 CFR Sec.  141.63(d)--Best                                       
technologies or other means to comply   Comments/Water quality concerns 
     (Complexity level indicated)                                       
------------------------------------------------------------------------
Protection of wells from               Ten States Standards and other   
 contamination, i.e., placement and     standards (AWWA A100-90) apply; 
 construction of well(s) (Basic).       interfacing with other programs 
                                        essential (e.g., source water   
                                        protection program).            
Maintenance of a disinfection          Source water constituents may    
 residual for distribution system       affect disinfection: iron,      
 protection (Intermediate).             manganese, organics, ammonia,   
                                        other factors may affect dosage 
                                        and water quality. TCR remains  
                                        unspecific on type/amount of    
                                        disinfectant, as each type      
                                        differs in concentration, time, 
                                        temperature, pH, interaction    
                                        with other constituents, etc.   
Proper maintenance of distribution     O&M programs particularly        
 system: pipe repair/replacement,       important for smaller systems   
 main flushing programs, storage/       needing to maintain water       
 reservoir and O&M programs             purity. States may vary on      
 (including cross-connection control/   distribution protection         
 backflow prevention), and              measures. See also EPA's Cross- 
 maintenance of positive pressure       Connection Control Manual (# EPA
 throughout (Intermediate).             570/9-89-007).                  

[[Page 42038]]

                                                                        
Filtration and/or Disinfection of      Same issues as cited above under 
 surface water or other groundwater     maintaining disinfection        
 under direct influence; or             residual; pretreatment          
 disinfection of groundwater (Basic     requirements affect complexity  
 thru Advanced).                        of operation. Refer to SWTR     
                                        Compliance Technology List; and 
                                        other regulations under         
                                        development.                    
Groundwaters: Compliance with State    EPA/State WHPP implementation    
 Well-Head Protection Program           (per Sec.  1428 SDWA): may be   
 (Intermediate).                        used to assess vulnerability to 
                                        contamination, and in           
                                        determination of sampling and   
                                        sanitary survey frequencies.    
------------------------------------------------------------------------

III. Small System Compliance Technology Lists for the Non-Microbial 
Contaminants Regulated Before 1996

A. Overview

    This notice announces the Small System Compliance Technology List 
for the non-microbial contaminants regulated before 1996. The list is 
divided by contaminant type into lists for inorganics (IOCs), volatile 
organic compounds (VOCs), pesticides and other synthetic organic 
compounds (SOCs), and radionuclides. Technologies for the removal of 
these contaminants were evaluated for performance and applicability to 
small systems. Criteria for evaluation included availability of 
published performance assessments, general limitations to use by the 
various small systems size categories, raw water quality requirements, 
and required operator skill level.
    There is one noteworthy group of technologies included on the 
compliance technology lists for IOCs, SOCs, and radionuclides. Point-
of-use (POU) devices have been identified as compliance technologies. 
Section 1412(b)(4)(E)(ii) of the SDWA identifies POU treatment units as 
an option for compliance technologies. This section also identifies 
Point-of-Entry (POE) devices as a compliance technology option. Section 
1412(b)(4)(E)(ii) stipulates that ``point-of-entry and point-of-use 
treatment units shall be owned, controlled, and maintained by the 
public water system or by a person under contract with the public water 
system to ensure proper operation and maintenance and compliance with 
the MCL or treatment technique and equipped with mechanical warnings to 
ensure that customers are automatically notified of operational 
problems.'' Other conditions in this section of the SDWA include: ``If 
the American National Standards Institute has issued product standards 
applicable to a specific type of POE or POU treatment unit, individual 
units of that type shall not be accepted for compliance with a MCL or 
treatment technique unless they are independently certified in 
accordance with such standards.''
    In order to list POU treatment units as compliance technologies, 
EPA had to delete the part of 40 CFR 141.101 that prohibited POU 
devices to be used to comply with an MCL. A final rule was published in 
the Federal Register on June 11, 1998 deleting the prohibition on the 
use of POU devices as compliance technologies. As previously mentioned, 
POU devices are listed as compliance technologies for IOCs, SOCs, and 
radionuclides. POU devices are not listed for VOCs because they do not 
address all routes of exposure. POE devices are still considered 
emerging technologies because of waste disposal and cost 
considerations. POE devices may be included on an updated list in 1999. 
For more detail on POU and POE devices, see the guidance manual 
entitled ``Compliance Technology List for Non-Microbial Contaminants 
Regulated Before 1996'' and the supporting document entitled ``Cost 
Evaluation of Small System Compliance Options: Point-of-Use and Point-
of-Entry Treatment Units.''
    Technologies for which sufficient information exists for 
evaluations are listed as compliance technologies. Those for which 
incomplete information exists, but which appear promising enough to be 
further evaluated, are listed as ``emerging technologies.'' Emerging 
technologies are only included in the guidance manuals. These 
compliance technology lists will be updated in 1999 if new information 
becomes available. The updated lists will provide further information 
on the listed compliance technology lists and may include additional 
technologies. In general, all of the compliance technology lists will 
continue to evolve over time as information is made available and as 
updates are published.

B. Availability of a Guidance Document

    The guidance document supporting these lists is entitled ``Small 
System Compliance Technology List for the Non-Microbial Contaminants 
Regulated Before 1996.'' The document may be obtained from EPA by 
calling the Safe Drinking Water Hotline at (800) 426-4791 after 
September 15, 1998. It is also accessible via the Internet at 
<www.epa.gov/safewater/pubs/index.html> after September 15, 1998.
    The guidance document is divided into chapters describing the SDWA 
requirements concerning the list, the technologies being evaluated, 
along with the criteria and other information necessary for evaluation, 
the annotated list of technologies chosen as compliance technologies, 
and the annotated list of technologies that require further evaluation. 
EPA expects to update this guidance document in 1999.

C. Compliance Technology List for the Non-Microbial Contaminants 
Regulated Before 1996

    The following tables contain the initial list of compliance 
technologies for the three small system size categories for the non-
microbial contaminants regulated before 1996: Inorganic contaminants 
(IOCs), volatile organic contaminants (VOCs), synthetic organic 
contaminants (SOCs), and radionuclides. A discussion of each technology 
can be found in the guidance document along with a more detailed 
analysis of technology limitations.
C1. Compliance Technologies for Inorganic Contaminants (IOCs)
    Table 4 contains the technologies that have been identified as 
compliance technologies for at least one IOC. The table contains the 
same structure as other tables with a list of limitations that are 
contained in the footnotes and operator skill level and raw water 
quality issues for general operation of the technology. The guidance 
manual will have more detailed information on the application of the 
technologies for particular contaminants.

[[Page 42039]]



                                         Table 4.--Technologies for IOCs                                        
----------------------------------------------------------------------------------------------------------------
                                        Limitations (see      Operator skill level                              
          Unit technology                  footnotes)               required           Raw water quality range  
----------------------------------------------------------------------------------------------------------------
1. Activated Alumina...............  (<SUP>a)...................  Advanced..............  Ground waters, Competing   
                                                                                      anion concentrations will 
                                                                                      affect run length.        
2. Ion Exchange (IX)...............                          Intermediate..........  Ground waters with low     
                                                                                      total dissolved solids,   
                                                                                      Competing ion             
                                                                                      concentrations will affect
                                                                                      run length.               
3. Lime Softening..................  (<SUP>b)...................  Advanced..............  Hard ground and surface    
                                                                                      waters.                   
4. Coagulation/Filtration..........  (<SUP>c)...................  Advanced..............  Can treat wide range of    
                                                                                      water quality.            
5. Reverse Osmosis (RO)............  (<SUP>d)...................  Advanced..............  Surface water usually      
                                                                                      require pre-filtration.   
6. Alkaline Chlorination...........  (<SUP>e)...................  Basic.................  All ground waters.         
7. Ozone Oxidation.................                          Intermediate..........  All ground waters.         
8. Direct Filtration...............                          Advanced..............  Needs high raw water       
                                                                                      quality.                  
9. Diatomaceous earth filtration...                          Intermediate..........  Needs very high raw water  
                                                                                      quality.                  
10. Granular Activated Carbon......                          Basic.................  Surface waters may require 
                                                                                      prefiltration.            
11. Electrodialysis Reversal.......                          Advanced..............  Requires prefiltration for 
                                                                                      surface water.            
12. POU--IX........................  (<SUP>f)...................  Basic.................  Same as Technology #2.     
13. POU--RO........................  (<SUP>f)...................  Basic.................  Same as Technology #5.     
14. Calcium Carbonate Precipitation  (<SUP>g)...................  Basic.................  Waters with high levels of 
                                                                                      alkalinity and calcium.   
15. pH and alkalinity adjustment     (<SUP>g)...................  Basic.................  All ranges.                
 (chemical feed).                                                                                               
16. pH and alkalinity adjustment     (<SUP>h)...................  Basic.................  Waters that are low in iron
 (limestone contactor).                                                               and turbidity. Raw water  
                                                                                      should be soft and        
                                                                                      slightly acidic.          
17. Inhibitors.....................                          Basic.................  All ranges.                
18. Aeration.......................  (<SUP>i)...................  Basic.................  Waters with moderate to    
                                                                                      high carbon dioxide       
                                                                                      content.                  
----------------------------------------------------------------------------------------------------------------
Limitations Footnotes to the Technology Tables for IOCs                                                         
<SUP>a Chemicals required during regeneration and pH adjustment may be difficult for small systems to handle.        
<SUP>b Softening chemistry may be too complex for small systems.                                                     
<SUP>c It may not be advisable to install coagulation/filtration solely for inorganics removal.                      
<SUP>d If all of the influent water is treated, post-treatment corrosion control will be necessary.                  
<SUP>e pH must exceed pH 8.5 to ensure complete oxidation without build-up of cyanogen chloride.                     
<SUP>f When POU devices are used for compliance, programs for long-term operation, maintenance, and monitoring must  
  be provided by water utility to ensure proper performance (see Section III.A of this notice).                 
<SUP>g Some chemical feeds require high degree of operator attention to avoid plugging.                              
<SUP>h This technology is recommended primarily for the smallest size category.                                      
<SUP>i Any of the first five aeration technologies listed for volatile organic contaminants can be used.             

    The background section indicated that EPA would identify affordable 
compliance technologies for those existing regulations where small 
system variances or variance technologies are not prohibited by the 
SDWA. There are statutory prohibitions against small system variances 
or variance technologies for 13 of the 17 IOCs. Table 5 contains the 
compliance technologies for the four IOCs where affordability was 
considered. Affordability only plays a role in removing some of the 
options in the smallest size category. The technology costs are based 
on treatment of all of the water. The technologies that did not meet 
the affordability criteria in the smallest size category are also 
identified in the next column called other compliance technologies. 
These technologies may be affordable if the concentration of the 
contaminant is low enough that a portion of the influent stream can be 
treated and blended with an untreated portion to still meet the MCL. 
Systems and States should consider these options under those 
circumstances. Table 6 contains the compliance technologies for the 
remaining thirteen IOCs where affordability was not considered due to 
statutory prohibitions. The statutory prohibitions on variance 
technologies and small system variances are discussed in detail in 
Section IV of this notice.

Table 5.--Compliance Technologies by System Size Category for Those IOC NPDWRs Where Affordability is Considered
----------------------------------------------------------------------------------------------------------------
                                      Compliance Technologies for System Size Categories  (Population Served)   
                                 -------------------------------------------------------------------------------
      Inorganic Contaminant                                                                      3,301-10,000   
                                   25-500  (afford)     25-500 (other)    501-3,300 (afford)       (afford)     
----------------------------------------------------------------------------------------------------------------
Antimony........................  13................  4, 5..............  4, 5, 13..........  4, 5, 13.         
Asbestos........................  8, 9, 15, 17......  4.................  4, 8, 9, 15, 17...  4, 8, 9, 15, 17.  
Cyanide.........................  2, 6, 7...........  5.................  2, 5, 6, 7........  2, 5, 6, 7.       
Lead............................  2, 12, 13, 14, 15,  3, 4, 5...........  2, 3, 4, 5, 12,     2, 3, 4, 5, 12,   
                                   16, 17, 18.                             13, 14, 15, 16,     13, 14, 15, 16,  
                                                                           17, 18.             17, 18.          
----------------------------------------------------------------------------------------------------------------


[[Page 42040]]


    Table 6.--Compliance Technologies by System Size Category for Those IOC NPDWRs Where Affordability Is Not   
                                                   Considered                                                   
----------------------------------------------------------------------------------------------------------------
                                        Compliance technologies for system size categories  (Population served) 
        Inorganic contaminant         --------------------------------------------------------------------------
                                                25-500                 501-3,300               3,301-10,000     
----------------------------------------------------------------------------------------------------------------
Arsenic..............................  1, 2, 3, 4, 5, 11, 12,   1, 2, 3, 4, 5, 11, 12,   1, 2, 3, 4, 5, 11, 12, 
                                        13.                      13.                      13.                   
Barium...............................  2, 3, 4, 5, 11, 12, 13.  2, 3, 4, 5, 11, 12, 13.  2, 3, 4, 5, 11, 12, 13.
Beryllium............................  1, 2, 3, 4, 5, 12, 13..  1, 2, 3, 4, 5, 12, 13..  1, 2, 3, 4, 5, 12, 13. 
Cadmium..............................  2, 3, 4, 5, 12, 13.....  2, 3, 4, 5, 12, 13.....  2, 3, 4, 5, 12, 13.    
Chromium.............................  2, 3,<SUP>a 4, 5, 12, 13....  2, 3,<SUP>a 4, 5, 12, 13....  2, 3,<SUP>a 4, 5, 12, 13.   
Copper...............................  2, 3, 4, 5, 12, 13, 15,  2, 3, 4, 5, 12, 13, 15,  2, 3, 4, 5, 12, 13, 15,
                                        16, 17, 18.              16, 17, 18.              16, 17, 18.           
Fluoride.............................  1, 5, 13...............  1, 5, 13...............  1, 5, 13.              
Mercury..............................  3,<SUP>b 4,<SUP>b 5,<SUP>b 10.........  3,<SUP>b 4,<SUP>b 5,<SUP>b 10.........  3,<SUP>b 4,<SUP>b 5,<SUP>b 10.        
Nitrate..............................  2, 5, 11...............  2, 5, 11...............  2, 5, 11.              
Nitrite..............................  2, 5...................  2, 5...................  2, 5.                  
Nitrate + Nitrite....................  2, 5, 11...............  2, 5, 11...............  2, 5, 11.              
Selenium.............................  1, 2,<SUP>c 3, 4,<SUP>d 5, 11,<SUP>d    1, 2,<SUP>c 3, 4,<SUP>d 5, 11,<SUP>d    1, 2,<SUP>c 3, 4,<SUP>d 5, 11,<SUP>d  
                                        13.                      13.                      13.                   
Thallium.............................  1, 2, 12...............  1, 2, 12...............  1, 2, 12.              
----------------------------------------------------------------------------------------------------------------
Footnotes for Table 6: Compliance Technologies for IOCs (affordability not considered)                          
<SUP>a Compliance technology for Chromium III only.                                                                  
<SUP>b Compliance technologies only when influent mercury concentrations <ls-thn-eq> 10 <greek-m>g/L.                
<SUP>c Compliance technology for Selenium VI only.                                                                   
<SUP>d Compliance technology for Selenium IV only.                                                                   

C2. Compliance Technologies for Volatile Organic Contaminants (VOCs)
    Table 7 contains the technologies that have been identified as 
compliance technologies for at least one VOC. The table contains the 
same structure as other tables with a list of limitations that are 
contained in the footnotes and operator skill level and raw water 
quality issues.

                                         Table 7.--Technologies for VOCs                                        
----------------------------------------------------------------------------------------------------------------
                                          Limitations  (see       Operator skill level   Raw water quality range
           Unit technology                    footnotes)              required \1\                 \1\          
----------------------------------------------------------------------------------------------------------------
1. Packed Tower Aeration (PTA).......  (<SUP>a)....................  Intermediate...........  All ground waters.     
2. Diffused Aeration.................  (<SUP>a <SUP>b)..................  Basic..................  All ground waters.     
3. Multi-Stage Bubble Aerators.......  (<SUP>a <SUP>c)..................  Basic..................  All ground waters.     
4. Tray Aeration.....................  (<SUP>a <SUP>d)..................  Basic..................  All ground waters.     
5. Shallow Tray Aeration.............  (<SUP>a <SUP>e)..................  Basic..................  All ground waters.     
6. Spray Aeration....................  (<SUP>a <SUP>f)..................  Basic..................  All ground waters.     
7. Mechanical Aeration...............  (<SUP>a <SUP>g)..................  Basic..................  All ground waters.     
8. Granular Activated Carbon (GAC)...  (<SUP>h)....................  Basic..................  All ground waters.     
----------------------------------------------------------------------------------------------------------------
\1\ National Research Council (NRC). Safe Water from Every Tap: Improving Water Service to Small Communities.   
  National Academy Press. Washington, DC. 1997.                                                                 
Limitations Footnotes to the Technology Tables for VOCs                                                         
<SUP>a Pretreatment for the removal of microorganisms, iron, manganese, and excessive particulate matter may be      
  needed. Post-treatment disinfection may have to be used.                                                      
<SUP>b May not be as efficient as other aeration methods because it does not provide for convective movement of the  
  water thus limiting air-water contact. It is generally used only to adapt existing plant equipment.           
<SUP>c These units are highly efficient, however the efficiency depends upon the air-to-water ratio.                 
<SUP>d Costs may increase if a forced draft is used. Slime and algae growth can be a problem, but can be controlled  
  with chemicals such as copper sulfate or chlorine.                                                            
<SUP>e These units require high air/water ratios (100-900 m\3\/m\3\)                                                 
<SUP>f For use only when low removal levels are needed to reach an MCL because these systems may not be as energy    
  efficient as other aeration methods because of the contacting system.                                         
<SUP>g For use only when low removal levels are needed to reach an MCL because these systems may not be as energy    
  efficient as other aeration methods because of the contacting system. The units often require large basins,   
  long residence times, and high energy inputs which may increase costs.                                        
<SUP>h See the SOCs compliance technology table for limitation regarding these technologies.                         

    The background section indicated that EPA would identify affordable 
compliance technologies for those existing regulations where small 
system variances or variance technologies are not prohibited by the 
SDWA. There are statutory prohibitions against small system variances 
or variance technologies for 2 of the 21 VOCs. Table 8 contains the 
compliance technologies for the 19 VOCs where affordability was 
considered. Affordability only plays a role in removing options in the 
smallest size category. The technology costs are based on treatment of 
all of the water. The technologies that did not meet the affordability 
criteria in the smallest size category are also identified in the next 
column called ``other compliance technologies.'' These technologies may 
be affordable if the concentration of the contaminant is low enough 
that a portion of the influent stream can be treated and blended with 
an untreated portion to still meet the MCL. This blending would reduce 
both the capital and operating and maintenance costs of the process. 
Systems and States should consider these options under those 
circumstances. Table 9 contains the compliance technologies for the 
remaining two VOCs where affordability was not considered due to 
statutory prohibitions. The statutory prohibitions on variance 
technologies and small system variances are discussed in detail in 
Section IV of this notice.

[[Page 42041]]



Table 8.--Compliance Technologies by System Size Category for Those VOC NPDWRs Where Affordability Is Considered
----------------------------------------------------------------------------------------------------------------
                                      Compliance technologies for system size categories  (Population served)   
                                 -------------------------------------------------------------------------------
  Volatile organic contaminant                                                 501-3,300         3,301-10,000   
                                   25-500  (afford)     25-500  (other)        (afford)            (afford)     
----------------------------------------------------------------------------------------------------------------
Benzene.........................  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Carbon Tetrachloride............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Chlorobenzene...................  1, 2, 3, 4, 5, 6,   8.................  1, 2, 3, 4, 5, 6,   1, 2, 3, 4, 5, 6, 
                                   7.                                      7, 8.               7, 8.            
cis-1,2-Dichlorobenzene.........  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
1,2-Dichloroethane..............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
1,1-Dichloroethylene............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Dichloromethane.................  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
1,2-Dichloropropane.............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Ethylbenzene....................  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
o-Dichlorobenzene...............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
p-Dichlorobenzene...............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Tetrachloroethylene.............  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Toluene.........................  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
trans-1,2-Dichloroethylene......  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
1,2,4-Trichlorobenzene..........  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
1,1,1-Trichloroethane...........  1, 2, 3, 4, 5, 6..  8.................  1, 2, 3, 4, 5, 6,   1, 2, 3, 4, 5, 6, 
                                                                           8.                  8.               
1,1,2-Trichloroethane...........  1, 2, 3, 4, 5,....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
Trichloroethylene...............  1, 2, 3, 4, 5, 6,   8.................  1, 2, 3, 4, 5, 6,   1, 2, 3, 4, 5, 6, 
                                   7.                                      7, 8.               7, 8.            
Xylenes (total).................  1, 2, 3, 4, 5.....  8.................  1, 2, 3, 4, 5, 8..  1, 2, 3, 4, 5, 8. 
----------------------------------------------------------------------------------------------------------------


    Table 9.--Compliance Technologies by System Size Category for Those VOC NPDWRs Where Affordability Is Not   
                                                   Considered                                                   
----------------------------------------------------------------------------------------------------------------
                                        Compliance technologies for system size categories  (Population served) 
    Volatile organic  contaminant     --------------------------------------------------------------------------
                                                25-500                 501-3,300               3,301-10,000     
----------------------------------------------------------------------------------------------------------------
Styrene..............................  1, 2, 3, 4, 5, 8.......  1, 2, 3, 4, 5, 8.......  1, 2, 3, 4, 5, 8.      
Vinyl Chloride.......................  1, 2, 3, 4, 5, 8.......  1, 2, 3, 4, 5, 8.......  1, 2, 3, 4, 5, 8.      
----------------------------------------------------------------------------------------------------------------

C3. Compliance Technologies for SOCs (Pesticides and Other SOCs).
    Table 10 contains the technologies that have been identified as 
compliance technologies for at least one SOC. The table contains the 
same structure as other tables with a list of limitations that are 
contained in the footnotes and operator skill level and raw water 
quality issues.

                                        Table 10.--Technologies for SOCs                                        
----------------------------------------------------------------------------------------------------------------
                                          Limitations (see       Operator skill level    Raw water quality range
           Unit technology                   footnotes)              required \1\        and considerations \1\ 
----------------------------------------------------------------------------------------------------------------
1. Granular Activated Carbon (GAC)..                           Basic..................  Surface water may       
                                                                                         require pre-filtration.
2. Point of Use (POU) GAC...........  (<SUP>a)....................  Basic..................  Surface water may       
                                                                                         require pre-filtration.
3. Powdered Activated Carbon........  (<SUP>b)....................  Intermediate...........  All waters.             
4. Chlorination.....................  (<SUP>c)....................  Basic..................  Better with high quality
                                                                                         water.                 
5. Ozonation........................  (<SUP>c)....................  Basic..................  Better with high quality
                                                                                         waters.                
6. Packed Tower Aeration (PTA)......  (<SUP>d)....................  Intermediate...........  All ground waters.      
7. Diffused Aeration................  (<SUP>d, <SUP>e).................  Basic..................  All ground waters.      
8. Multi-Stage Bubble Aerators......  (<SUP>d <SUP>f)..................  Basic..................  All ground waters.      
9. Tray Aeration....................  (<SUP>d <SUP>g)..................  Basic..................  All ground waters.      
10. Shallow Tray Aeration...........  (<SUP>d <SUP>f)..................  Basic..................  All ground waters.      
----------------------------------------------------------------------------------------------------------------
\1\ National Research Council (NRC). Safe Water from Every Tap: Improving Water Service to Small Communities.   
  National Academy Press. Washington, DC. 1997.                                                                 
Limitations footnotes for Table 10: Technologies for SOCs                                                       
<SUP>a When POU devices are used for compliance, programs for long-term operation, maintenance, and monitoring must  
  be provided by water utility to ensure proper performance (see Section III.A of this notice).                 
<SUP>b Most applicable to small systems that already have a process train including basins mixing, precipitation or  
  sedimentation, and filtration. Site specific design should be based on studies conducted on the system's      
  particular water.                                                                                             
<SUP>c See the SWTR compliance technology tables for limitations associated with this technology.                    
<SUP>d Pretreatment for the removal of microorganisms, iron, manganese, and excessive particulate matter may be      
  needed. Post-treatment disinfection may have to be used.                                                      
<SUP>e May not be as efficient as other aeration methods because it does not provide for convective movement of the  
  water thus limiting air-water contact. It is generally used only to adapt existing plant equipment.           
<SUP>f This units are highly efficient, however the efficiency depends upon the air-to-water ratio.                  

[[Page 42042]]

                                                                                                                
<SUP>g Costs may increase if a forced draft is used.                                                                 

    The background section indicated that EPA would identify affordable 
compliance technologies for those existing regulations where small 
system variances or variance technologies are not prohibited by the 
SDWA. There are statutory prohibitions against small system variances 
or variance technologies for 14 of the 32 SOCs. Table 11 contains the 
compliance technologies for the 18 SOCs where affordability was 
considered. Affordability only plays a role in removing options in the 
smallest size category. The technology costs are based on treatment of 
all of the water. The technologies that did not meet the affordability 
criteria in the smallest size category are also identified in the next 
column called ``other compliance technologies.'' These technologies may 
be affordable if the concentration of the contaminant is low enough 
that a portion of the influent stream can be treated and blended with 
an untreated portion to still meet the MCL. This blending would reduce 
both the capital and operating and maintenance costs of the process. 
Systems and States should consider these options under those 
circumstances. Table 12 contains the compliance technologies for the 
remaining fourteen SOCs where affordability was not considered due to 
statutory prohibitions. The statutory prohibitions on variance 
technologies and small system variances are discussed in detail in 
Section IV of this notice.

     Table 11.--Compliance Technologies by System Size Category for Those SOC NPDWRs Where Affordability Is     
                                                   Considered                                                   
----------------------------------------------------------------------------------------------------------------
                                      Compliance technologies for system size categories  (Population served)   
                                 -------------------------------------------------------------------------------
           Contaminant                                                         501-3,300         3,301-10,000   
                                   25-500  (afford)     25-500  (other)        (afford)            (afford)     
----------------------------------------------------------------------------------------------------------------
Alachlor........................  2, 3 <SUP>a............  1.................  1, 2, 3...........  1, 2, 3.          
Atrazine........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Carbofuran......................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Dibromochloropropane............  2, 3, 6, 7, 8, 9,   1.................  1, 2, 3, 6, 7, 8,   1, 2, 3, 6, 7, 8, 
                                   10.                                     9, 10.              9, 10.           
2,4-D...........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Lindane.........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Methoxychlor....................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Pentachlorophenol...............  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Dalapon.........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Di(2-ethylhexyl) adipate........  2, 3, 6, 7, 8, 9,   1.................  1, 2, 3, 6, 7, 8,   1, 2, 3, 6, 7, 8, 
                                   10.                                     9, 10.              9, 10.           
Di(2-ethylhexyl) phthalate......  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Dinoseb.........................  2, 3..............  1.................  1, 2, 3...........   1, 2, 3          
Diquat..........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Endothall.......................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Glyphosate......................  4, 5..............  ..................  4, 5..............  4, 5.             
Hexachlorocyclopentadiene.......  2, 3, 6, 7, 8, 9,   1.................  1, 2, 3, 6, 7, 8,   1, 2, 3, 6, 7, 8, 
                                   10.                                     9, 10.              9, 10.           
Picloram........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
Simazine........................  2, 3..............  1.................  1, 2, 3...........  1, 2, 3.          
----------------------------------------------------------------------------------------------------------------
<SUP>a This affordability determination assumes that the small system already has the appropriate treatment train in 
  place for mixing, contact, and filtration.                                                                    


   Table 12.--Compliance Technologies by System Size Category for those SOC NPDWRs where Affordability is Not   
                                                   Considered                                                   
----------------------------------------------------------------------------------------------------------------
                                        Compliance technologies for system size categories  (population served) 
             Contaminant              --------------------------------------------------------------------------
                                                25-500                 501-3,300               3,300-10,000     
----------------------------------------------------------------------------------------------------------------
Chlordane............................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Ethylene Dibromide...................  1, 2, 3, 6, 7, 8, 9, 10  1, 2, 3, 6, 7, 8, 9, 10  1, 2, 3, 6, 7, 8, 9,   
                                                                                          10.                   
Heptachlor...........................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Heptachlor Epoxide...................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Polychlorinated Biphenyls............  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Toxaphene............................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
2,4,5-TP.............................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Benzo(a)pyrene.......................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Endrin...............................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Hexachlorobenzene....................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Oxamyl...............................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
2,3,7,8-TCDD (Dioxin)................  1, 2, 3................  1, 2, 3,...............  1, 2, 3.               
Acrylamide...........................  N/A (treatment           N/A (treatment           N/A (treatment         
                                        technique).              technique).              technique).           
Epichlorohydrin......................  N/A....................  N/A....................  N/A.                   
----------------------------------------------------------------------------------------------------------------


[[Page 42043]]

C4. Compliance Technologies for Radionuclides
    Table 13 contains the technologies that have been identified as 
compliance technologies for at least one radionuclide. The table 
contains the same structure as other tables with a list of limitations 
that are contained in the footnotes and operator skill level and raw 
water quality issues.

                                    Table 13.--Technologies for Radionuclides                                   
----------------------------------------------------------------------------------------------------------------
                                          Limitations  (see       Operator skill level   Raw water quality range
          Unit technologies                   footnotes)              required \1\           & considerations   
----------------------------------------------------------------------------------------------------------------
1. Ion Exchange (IE).................  (<SUP>a)....................  Intermediate...........  All ground waters.     
2. Point of Use (POU) IE.............  (<SUP>b)....................  Basic..................  All ground waters.     
3. Reverse Osmosis (RO)..............  (<SUP>c)....................  Advanced...............  Surface waters. usually
                                                                                          require pre-          
                                                                                          filtration.           
4. POU RO............................  (<SUP>b)....................  Basic..................  Surface waters usually 
                                                                                          require pre-          
                                                                                          filtration.           
5. Lime Softening....................  (<SUP>d)....................  Advanced...............  All waters.            
6. Green Sand Filtration.............  (<SUP>e)....................  Basic..................                         
7. Co-precipitation with Barium        (<SUP>f)....................  Intermediate to          Ground waters with     
 Sulfate.                                                        Advanced.                suitable water        
                                                                                          quality.              
8. Electrodialysis/Electrodialysis                              Basic to Intermediate..  All ground waters.     
 Reversal.                                                                                                      
9. Pre-formed Hydrous Manganese Oxide  (<SUP>g)....................  Intermediate...........  All ground waters.     
 Filtration.                                                                                                    
----------------------------------------------------------------------------------------------------------------
\1\ National Research Council (NRC). Safe Water from Every Tap: Improving Water Service to Small Communities.   
  National Academy Press. Washington, D.C. 1997.                                                                
Limitations Footnotes to Table 13: Technologies for Radionuclides                                               
<SUP>a The regeneration solution contains high concentrations of the contaminant ions. Disposal options should be    
  carefully considered before choosing this technology.                                                         
<SUP>a When POU devices are used for compliance, programs for long-term operation, maintenance, and monitoring must  
  be provided by water utility to ensure proper performance (see Section III.A of this notice).                 
<SUP>c Reject water disposal options should be carefully considered before choosing this technology. See other RO    
  limitations described in the SWTR Compliance Technologies Table.                                              
<SUP>d The combination of variable source water quality and the complexity of the chemistry involved in lime         
  softening may make this technology too complex for small surface water systems.                               
<SUP>e Removal efficiencies can vary depending on water quality.                                                     
<SUP>f This technology may be very limited in application to small systems. Since the process requires static mixing,
  detention basins, and filtration, it is most applicable to systems with sufficiently high sulfate levels that 
  already have a suitable filtration treatment train in place.                                                  
<SUP>g This technology is most applicable to small systems that already have filtration in place.                    

    The background section indicated that EPA would identify affordable 
compliance technologies for those existing regulations where small 
system variances or variance technologies are not prohibited by the 
SDWA. There are statutory prohibitions against small system variances 
for all three radionuclides. Table 14 contains the compliance 
technologies the three radionuclides without considering affordability 
due to statutory prohibitions. The statutory prohibitions on variance 
technologies and small system variances are discussed in detail in 
Section IV of this notice.

    Table 14.--Compliance Technologies by System Size Category for Radionuclide NPDWRs, Affordability is Not    
                                                   Considered                                                   
----------------------------------------------------------------------------------------------------------------
                                           Compliance technologies\1\ for system size categories  (Population   
--------------------------------------                                  Served)                                 
                                      --------------------------------------------------------------------------
             Contaminant                        25-500                 501-3,300               3,300-10,000     
----------------------------------------------------------------------------------------------------------------
Combined radium-226 and radium-228...  1, 2, 3, 4, 5, 6, 7, 8,  1, 2, 3, 4, 5, 6, 7, 8,  1, 2, 3, 4, 5, 6, 7, 8,
                                        9.                       9.                       9.                    
Gross alpha particle activity........  3, 4...................  3, 4...................  3, 4.                  
Total beta particle activity and       1, 2, 3, 4.............  1, 2, 3, 4.............  1, 2, 3, 4.            
 photon activity, average annual                                                                                
 concentration.                                                                                                 
----------------------------------------------------------------------------------------------------------------
\1\ (Note: 1) Numbers correspond to those assigned to technologies found in the Compliance Technologies Table   
  for Radionuclides.                                                                                            

D. Stakeholder Involvement and State Consultation

    EPA held a stakeholder meeting on May 18 and 19, 1998. The meeting 
took place at RESOLVE, 1255 23rd Street, N.W., Washington, D.C. 
Approximately 50 people registered and participated in the meeting. 
Representatives from nine States were present at the meeting (either at 
Resolve or on the conference lines) and several others received the 
material that was sent out prior to the meeting for review. A draft of 
the ``Cost Evaluation of Small System Compliance Options: Point-of-Use 
and Point-of-Entry Treatment Units'' was sent out prior to the meeting.
    Compliance technology options were presented for each group of 
contaminants: IOCs, VOC, SOCs and radionuclides on the second day of 
the stakeholder meeting. A final presentation on POU and POE devices

[[Page 42044]]

followed the sessions on the contaminant groups. Since most of the 
compliance technologies identified for these groups of contaminants 
were the best available technologies (BATs) listed in the regulations, 
there were very few significant comments on those presentations. There 
were a number of significant comments on the POU and POE options, since 
they were not listed as BATs. The significant comments on the 
compliance technology list for the non-microbial contaminants regulated 
before 1996 are as follows:
    <bullet> One State representative noted that the precipitation 
approach can cause problems for consumers' water heating tanks. Several 
stakeholders indicated that pH adjustment using limestone contactors is 
the least complex process. EPA has included both of these options as 
compliance technologies for lead. The precipitation approach is not 
listed as a compliance technology for copper.
    <bullet> Residuals management was identified as a major factor that 
would influence technology selection for IOCs. The guidance provides 
additional details on the residuals produced by each process.
    <bullet> Stakeholders recommended the inclusion of mechanical 
aeration and spray aeration, where appropriate, for VOCs along with the 
limitations that might limit their applicability.
    <bullet> Stakeholders believed that more data is needed on removal 
of pesticides by technologies other than carbon, such as membranes. EPA 
has listed these technologies as ``emerging'' technologies and hopes to 
generate more data over the coming year.
    <bullet> Residuals management was identified as a major factor that 
would influence technology selection for radionuclides. Stakeholders 
recommended that EPA investigate discharges to septic systems when POU 
reverse osmosis or ion exchange systems are used as compliance 
technologies.
    <bullet> States and other stakeholders recommended that EPA 
consider listing POU devices as compliance technologies for nitrate by 
adding a public education component. POU devices are listed as an 
emerging technology, while EPA determines the necessary requirements of 
a public education program for nitrate.
    <bullet> States and other stakeholders agreed with EPA's assessment 
that POU devices would not be appropriate for VOCs because they do not 
address all exposure pathways.
    <bullet> EPA indicated that the cost estimates for POU and POE 
options were based on conservative assumptions about water consumption 
and monitoring requirements. Stakeholders did provide comments on these 
assumptions and EPA will develop other cost estimates.
    At the end of the stakeholder meeting, EPA indicated that it 
welcomed comments on any of the material in the presentations on 
compliance technology options for non-microbial contaminants. The only 
comments received dealt with the assumptions used to estimate POU and 
POE costs for water systems.

IV. Variance Technology Findings for Contaminants Regulated Before 
1996

A1. Overview

    As previously discussed, compliance and variance technologies are 
mutually exclusive. The two compliance technology list sections 
provided compliance technologies for all of the 80 regulated 
contaminants, including affordable compliance technologies for all 
classes of small systems where appropriate. Thus, EPA will not, at this 
time, be listing variance technologies for any existing NPDWR.
    The following is a brief discussion of the Agency's approach for 
determining whether and which variance technologies should be listed 
for existing regulated drinking water contaminants, as required under 
SDWA Section 1412(b)(15)(D). The guidance manual contains more detail, 
as noted earlier. Because this is the first time that EPA has 
undertaken the variance technology analysis required under the amended 
SDWA (which includes new findings concerning ``affordability'' and 
``protectiveness'') and given the relatively short time for development 
of this analysis, EPA considers the methodology described here and the 
resulting finding of no variance technologies to be an initial 
screening effort, rather than a final determination of any kind. In 
addition, by enabling EPA to list compliance and variance technologies 
rather than specifying them by regulation, the statute specifically 
contemplates that this analysis (and any resulting list) would be 
subject to revision based on new information and petitions from 
interested parties. EPA would be very interested in suggestions from 
the public, and particularly from States, about how to improve the 
methodology outlined here and discussed in the guidance and in variance 
technologies that EPA should consider in revising and updating any 
future variance technology list.
    In summary, EPA's methodology is as follows. A two-stage screening 
process was used to identify those contaminants that would be compared 
against the national-level affordability criteria. Three contaminants 
were removed prior to the two-stage screening process. The current 
total trihalomethane regulation only applies to systems serving greater 
than 10,000 people. Therefore, small systems do not have to meet the 
existing standard, so neither compliance nor variance technologies will 
be listed. Acrylamide and epichlorohydrin are compounds associated with 
chemical additives used in drinking water treatment. These contaminants 
are regulated through a treatment technique that requires a 
certification that the product of the dose and monomer concentration 
will not exceed certain levels. Treatment technology is not installed 
to remove the contaminants under this treatment technique. As such, 
there are no compliance or variance technologies for either of these 
two contaminants. Table 16 at the end of this section summarizes the 
process that was used on each contaminant.

A2. Two-Stage Screening Process for Variance Technology Eligibility

    The first stage of the screening process was an evaluation of 
statutory screens that limit the availability of small system variances 
or variance technologies. There are three statutory screens. The first 
two prohibit small system variances. The sole purpose of the listing of 
variance technologies is to enable small systems to obtain a small 
system variance. Therefore, when these small system variances are not 
available under the SDWA, variance technologies will not be specified. 
The third statutory screen is a restriction on the listing of variance 
technologies.
    The first statutory screen is in Section 1415(e)(6)(B) of the SDWA. 
Small system variances are not available for any microbial contaminant 
(including a bacterium, virus, or other organism) or an indicator or 
treatment technique for a microbial contaminant. This screen removes 6 
contaminants from the consideration for variance technologies.
    The second statutory screen is in Section 1415(e)(6)(A) of the 
SDWA. Small system variances are not available for any MCL or treatment 
technique with respect to which a NPDWR was promulgated prior to 
January 1, 1986. The Variance and Exemption Rule describes EPA's 
interpretation of this section of the SDWA (see 63 Fed. Reg. 19442; 
April 20, 1998). For this analysis, variance technologies are not 
available for those contaminants where the pre-1986 MCL has been 
retained or raised. This screen removes 12 contaminants from 
consideration.
    The final statutory screen is in Section 1412(b)(15)(B) of the 
SDWA. The Administrator shall not identify any

[[Page 42045]]

variance technology under this paragraph, unless the Administrator has 
determined, considering the quality of the source water to be treated 
and the expected useful life of the technology, that the variance 
technology is protective of public health. The procedures developed by 
EPA to define ``protective of public health'' levels are described in 
detail in the guidance document for the variance technology screening 
effort. In summary, EPA used available data to estimate Unreasonable 
Risk to Health (URTH) values for the contaminants remaining after the 
first two screens. The URTH values were used as a surrogate for the 
protection of public health requirement of Section 1412(b)(15)(B) 
because the URTH values are based on a short-term exposure of up to 7 
years. Section 1412(b)(15)(B) requires that the variance technology be 
protective of public health for the expected useful life of the 
technology. Most technologies will have expected useful lives greater 
than 7 years, so a concentration that is protective of public health 
would need to be less than or equal to the URTH value. For 19 
contaminants, the derived URTH value was equal to the MCL or very close 
to the MCL. For these 19 contaminants, it was determined that in order 
to be protective of public health, the MCL had to be met. Since the MCL 
is the treatment standard, compliance technologies are the only 
alternative. Variance technologies are not listed for these 
contaminants.
    The second stage of the screening process involved affordability 
screens and evaluations. Since the statute authorizes a variance 
technology listing only where compliance technologies are unaffordable 
for any category of small systems, any contaminant that has a low-cost 
compliance technology will not have variance technologies. For this 
screen, the best available technologies listed in the regulations were 
examined and technologies that imposed an increase of less than $300/
household/year for each size category were identified to screen for 
affordability. The technologies that met this screening criterion were 
aeration, aeration plus chlorination, corrosion control, and oxidation. 
This screen removed 24 contaminants from consideration.
    The next affordability screen involved an evaluation of compliance 
monitoring data and National Pesticide Survey data for the remaining 16 
contaminants (14 pesticides). EPA assumed that if there were no 
violations, existing technologies for compliance have been affordable. 
Six pesticides were removed from consideration based on the following 
criteria: no detections in the National Pesticide Survey, MCLs at least 
one order of magnitude higher than the reporting limit for the 
compliance monitoring data, and a low positive rate in the compliance 
data with no MCL exceedances. Violations for the remaining 10 
contaminants were then examined in the Safe Drinking Water Information 
System (SDWIS). Since only systems with violations of the MCL will 
require treatment, 5 contaminants were removed because there were no 
MCL violations.
    The results of the two-stage screening process were that only five 
contaminants remained eligible for variance technologies and would 
proceed through a more extensive affordability analysis. These five 
contaminants were: antimony, asbestos, atrazine, di-(2-ethylhexyl) 
phthalate and lindane. The extensive affordability analysis used 
national-level affordability criteria to determine if there is an 
affordable compliance technology. The derivation of the national-level 
affordability criteria are described below.

A3. National-Level Affordability Criteria

    As discussed in the background section, EPA did evaluate 
technologies for each small size category against an affordable 
technology criterion for those regulations where a small system 
variance could be granted. These size category-dependent affordable 
technology criteria are collectively referred to as ``national-level 
affordability criteria.'' This nomenclature has been used to 
distinguish the national-level affordability criteria from the 
affordability criteria that States will use for determinations 
affecting individual systems. EPA published information regarding these 
``State-level'' affordability criteria in February, 1998 (EPA-816-R-98-
002, Information for States on Developing Affordability Criteria for 
Drinking Water). Technologies determined to be ``unaffordable'' under 
the national-level affordability criteria may still be affordable for a 
specific system within the size category, in which case the system may 
install that technology if it so chooses. Conversely, if a financially 
disadvantaged small water system out of compliance with a NPDWR cannot 
afford any of the compliance technologies that are determined to be 
``affordable'' under the national-level affordability criteria, one 
option for that system would be to apply to the State for an exemption. 
Other options are described in the EPA document cited above, 
Information for States on Developing Affordability Criteria for 
Drinking Water.
    To determine if there are any affordable compliance technologies 
for a given NPDWR, the national-level affordability criteria are 
compared against the cost estimates for the applicable treatment 
technologies. To make this comparison, there must be a consistent unit 
of measure for both parameters. The selected approach was to measure 
user burden as the increase to annual household water bills that would 
result from installation of treatment. For community water systems, the 
household was selected as the most sensitive user for cost increases 
(see background document entitled National-Level Affordability Criteria 
Under the 1996 Amendments of the Safe Drinking Water Act). A second 
document evaluated non-community water systems (NCWS) and compared 
their vulnerability to cost increases with households in community 
water systems (see background document entitled An Assessment of the 
Vulnerability of Non-community Water Systems to SDWA Cost Increases). 
The conclusion based on this comparison was that the categories of NCWS 
were either not vulnerable to SDWA-related treatment cost increases or 
were less vulnerable to SDWA-related treatment cost increases than a 
typical household.
    A summary of the methodology used to determine the national-level 
affordability criteria is described below. The household is the focus 
of the national-level affordability analysis. Treatment technology 
costs are presumed affordable to the typical household if they can be 
shown to be within an affordability index range (defined as a range of 
percentages of median household income) that appears reasonable when 
compared to other household expenditures. This approach is based on the 
assumption that affordability to the median household served by the CWS 
can serve as an adequate proxy for the affordability of technologies to 
the system itself. EPA has chosen to express the water system financial 
and operational characteristics using their median values, which is a 
measure of their respective central tendencies. EPA believes that the 
national-level affordability criteria should describe the 
characteristics of typical systems and should not address extreme 
situations where costs might be extremely low or excessively 
burdensome.
    After selecting the impacts on households as the measure for 
comparing national-level affordability and treatment costs, a 
consistent set of units was needed to make the

[[Page 42046]]

comparison. The treatment cost models produce rate increases measured 
in dollars/thousand gallons ($/kgal). Annual household water 
consumption is needed to convert the treatment technology costs into 
the increase in annual household water bills. Multiplying the rate 
increase by the annual household consumption yields the increase to 
annual household water bills ($/household/year increase).
    The national-level affordability criteria have two major 
components: current annual water bills (baseline) and the affordability 
threshold. The current annual household water bills were subtracted 
from the affordability threshold to determine the maximum increase that 
can be imposed by treatment and still be considered affordable. This 
difference was compared with the converted treatment costs to make the 
affordable technology determinations. This difference is called the 
available expenditure margin.
    The affordability threshold was determined by comparing the cost of 
public water supply for households with other household expenditures 
and risk-averting behavior. National expenditure estimates were derived 
to illustrate the current allocation of household income across a range 
of general household expenditures. This consumer expenditure data 
provided a basis for determining the affordability threshold by 
comparing baseline household water costs to median household income 
(MHI) to determine the financial impact of increased water costs on 
households.
    There are three parameters needed for each size category to perform 
the affordable technology analysis. These parameters are: annual 
household consumption, current annual water bills, and median household 
income. The annual household water consumption and the current annual 
water bills were derived directly from data in the 1995 Community Water 
System Survey. The median household income data were derived by linking 
the CWSS data with data in the 1990 Census using zip codes.
    The national-level affordability criteria are based on an 
affordability threshold of 2.5% of the median household income (MHI). 
The rationale for the selection of 2.5% MHI as the affordability 
threshold is provided in the guidance document entitled ``Variance 
Technology Findings for Contaminants Regulated Before 1996.'' For each 
size category, median values have been used for annual household water 
consumption, baseline annual water bills, and median household income. 
The baseline water bills ranged from 0.75% to 0.78% MHI in the three 
size categories. Thus, the available expenditure margin were 
approximately 1.75% MHI for each size category. The following table 
summarizes the national-level affordability criteria and shows the 
maximum increase that could occur using these criteria. Most systems 
would not be expected to actually experience cost increases of this 
magnitude if a compliance technology was installed. Many compliance 
technologies impose substantially lower household costs. For example, 
the screening process examined several technologies that imposed less 
than $300/household per year increases in all three size categories. 
Appendix F of the ``National-Level Affordability Criteria Under the 
1996 Amendments to the Safe Drinking Water Act'' report lists 
mitigating measures that could reduce the impact on households. In 
addition, the national-level affordability criteria do not consider the 
impact of financial assistance from State Revolving Fund loans or other 
sources. This financial assistance could also reduce the impact on 
households in those systems that qualify for financial assistance.

                                Table 15.--National-Level Affordability Criteria                                
----------------------------------------------------------------------------------------------------------------
                                                     Baseline                                        Available  
                                 ------------------------------------------------  Affordability    expenditure 
  System size population served                     Water bills     Water bills      threshold    margin  ($/hh/
                                     Mean MHI        ($/hh/yr)        (%MHI)        (2.5% MHI)    year increase)
----------------------------------------------------------------------------------------------------------------
25-500..........................         $30,626            $228            0.75            $766            $537
501-3,300.......................          26,672             204            0.76             667             463
3,301-10,000....................          27,641             217            0.78             691             474
----------------------------------------------------------------------------------------------------------------

A4. Affordable Technology Analysis using National-Level Affordability 
Criteria

    Violation data on the five contaminants that passed through the 
screening process were used to estimate the needed removal efficiency. 
The highest violation for each contaminant was determined and confirmed 
with the State. Technology cost estimates to reach the MCL from the 
highest confirmed violation were compared against the available 
expenditure margin for each size category (see Table 15). Technology 
cost estimates were derived for both central treatment options and 
centrally-managed Point-of-Use and Point-of-Entry device options. The 
procedures followed for this analysis are described in detail in the 
background document entitled ``Variance Technology Findings for 
Contaminants Regulated Prior to 1996.'' Based on this analysis, an 
affordable compliance technology was found for each of the five 
contaminants for all system sizes and expected source water qualities. 
For most of the system size/source water quality combinations, there 
are multiple affordable technologies. The following table summarizes 
the rationale for a finding of no variance technologies for each of the 
80 regulated contaminants.

Table 16.--Rationale for the Lack of Variance Technologies for Regulated
                              Contaminants                              
------------------------------------------------------------------------
                Contaminant                           Rationale         
------------------------------------------------------------------------
Giardia lamblia...........................  Section 1415(e)(6)(B) of    
                                             SDWA.                      
Legionella................................  Section 1415(e)(6)(B) of    
                                             SDWA.                      
Standard Plate Count......................  Section 1415(e)(6)(B) of    
                                             SDWA.                      
Turbidity.................................  Section 1415(e)(6)(B) of    
                                             SDWA.                      
Viruses...................................  Section 1415(e)(6)(B) of    
                                             SDWA.                      
Total Coliform............................  Section 1415(e)(6)(B) of    
                                             SDWA.                      
Arsenic...................................  Section 1415(e)(6)(A) of    
                                             SDWA.                      
Beta particle & photon radioactivity......  Section 1415(e)(6)(A) of    
                                             SDWA.                      
Gross alpha particle activity.............  Section 1415(e)(6)(A) of    
                                             SDWA.                      
Radium 226 & 228 (combined)...............  Section 1415(e)(6)(A) of    
                                             SDWA.                      

[[Page 42047]]

                                                                        
Total Trihalomethanes.....................  MCL does not apply (applies 
                                             only to systems > 10,000   
                                             people).                   
Benzene...................................  Affordability Screen.       
Carbon Tetrachloride......................  Affordability Screen.       
p-Dichlorobenzene.........................  Affordability Screen.       
1,2-Dichloroethane........................  Affordability Screen.       
1,1-Dichloroethylene......................  Affordability Screen.       
1,1,1-Trichloroethane.....................  Affordability Screen.       
Trichloroethylene.........................  Affordability Screen.       
Vinyl Chloride............................  Section 1412(b)(15)(B)      
Chlorobenzene.............................  Affordability Screen.       
o-Dichlorobenzene.........................  Affordability Screen.       
cis-1,2-Dichloroethylene..................  Affordability Screen.       
trans-1,2-Dichloroethylene................  Affordability Screen.       
1,2-Dichloropropane.......................  Affordability Screen.       
Ethylbenzene..............................  Affordability Screen.       
Styrene...................................  Section 1412(b)(15)(B).     
Tetrachloroethylene.......................  Affordability Screen.       
Toluene...................................  Affordability Screen.       
Xylenes (total)...........................  Affordability Screen.       
Dichloromethane...........................  Affordability Screen.       
1,2,4-Trichlorobenzene....................  Affordability Screen.       
1,1,2-Trichloroethane.....................  Affordability Screen.       
Alachlor..................................  Violation Screen.           
Atrazine..................................  Affordable Technology Found.
Carbofuran................................  Violation Screen.           
Chlordane.................................  Section 1412(b)(15)(B).     
Dibromochloropropane......................  Affordability Screen.       
2,4-D.....................................  Violation Screen.           
Ethylene Dibromide........................  Section 1412(b)(15)(B).     
Heptachlor................................  Section 1412(b)(15)(B).     
Heptachlor Epoxide........................  Section 1412(b)(15)(B).     
Lindane...................................  Affordable Technology Found.
Methoxychlor..............................  Violation Screen.           
Polychlorinated Biphenyls.................  Section 1412(b)(15)(B).     
Pentachlorophenol.........................  Violation Screen.           
Toxaphene.................................  Section 1412(b)(15)(B).     
2,4,5-TP..................................  Section 1415(e)(6)(A).      
Benzo(a)pyrene............................  Section 1412(b)(15)(B).     
Dalapon...................................  Violation Screen.           
Di(2-ethylhexyl) adipate..................  Affordability Screen.       
Di(2-ethylhexyl) phthalate................  Affordable Technology Found.
Dinoseb...................................  Violation Screen.           
Diquat....................................  Violation Screen.           
Endothall.................................  Violation Screen.           
Endrin....................................  Section 1415(e)(6)(A).      
Glyphosate................................  Affordability Screen        
Hexachlorobenzene.........................  Section 1412(b)(15)(B).     
Hexachlorocyclopentadiene.................  Affordability Screen.       
Oxamyl....................................  Section 1412(b)(15)(B).     
Picloram..................................  Violation Screen.           
Simazine..................................  Violation Screen.           
2,3,7,8-TCDD (Dioxin).....................  Section 1412(b)(15)(B).     
Acrylamide................................  Not a technology-based      
                                             NPDWR.                     
Epichlorohydrin...........................  Not a technology-based      
                                             NPDWR.                     
Fluoride..................................  Section 1415(e)(6)(A).      
Asbestos..................................  Affordable Technology Found.
Barium....................................  Section 1415(e)(6)(A).      
Cadmium...................................  Section 1412(b)(15)(B).     
Chromium..................................  Section 1415(e)(6)(A).      
Mercury...................................  Section 1415(e)(6)(A).      
Nitrate (as N)............................  Section 1415(e)(6)(A).      
Nitrite (as N)............................  Section 1412(b)(15)(B).     
Total Nitrate & Nitrite (as N)............  Section 1412(b)(15)(B).     
Selenium..................................  Section 1415(e)(6)(A).      
Antimony..................................  Affordable Technology Found.
Beryllium.................................  Section 1412(b)(15)(B).     
Cyanide (as free cyanide).................  Section 1412(b)(15)(B).     
Thallium..................................  Section 1412(b)(15)(B).     
Lead......................................  Affordability Screen.       
Copper....................................  Section 1412(b)(15)(B).     
------------------------------------------------------------------------

    Based on the evaluation outlined above, EPA has found that there is 
currently no basis to list variance technologies for any of the 80 
regulated contaminants. EPA believes that this is a reasonable outcome. 
One of the findings in the National-Level Affordability Criteria 
Document is that water has historically been underpriced, and as a 
result, prices have increased at a higher rate over the last several 
years than other household utilities as demonstrated by the consumer 
price index for utilities. Since water rates are increasing faster than 
median household incomes, additional treatment, beyond that currently 
required, may increasingly become ``unaffordable'' based on the 
national-level affordability criteria. Another factor that will 
increase treatment costs is the promulgation of new regulations. The 
application of treatment technology to comply with those regulations 
will increase the baseline water bills. Thus, while variance 
technologies are not being specified for the existing regulations, they 
may well be listed for future regulations since the available 
expenditure margin will shrink as additional treatment is required.

B. Availability of guidance document explaining why there is no need at 
present for any variance technology

    This list is supported by the updated guidance document entitled 
``Variance Technology Findings for Contaminants Regulated Before 1996'' 
that will be released on September 15, 1998. The guidance document 
provides more detail on the two-stage screening process, the national-
level affordability criteria and the finding that there is currently no 
basis to list variance technologies for the 80 regulated contaminants.

C. Stakeholder Involvement and State Consultation

    EPA held a stakeholder meeting on May 18 and 19, 1998. The meeting 
took place at RESOLVE, 1255 23rd Street, N.W., Washington, D.C. 
Approximately 50 people registered and participated in the meeting. 
Representatives from nine States were present at the meeting (either at 
Resolve or on the conference lines) and several others received the 
material that was sent out prior to the meeting for review. A draft of 
the ``National-Level Affordability Criteria Under the 1996 Amendments 
to the Safe Drinking Water Act'' was sent out prior to the meeting.
    The first topic discussed on May 18, 1998 was the two-stage 
screening process that identified only five of the eighty regulated 
contaminants as being potential candidates for variance technologies. 
The major comments from general stakeholders and comments from States 
are summarized below:
    <bullet> The occurrence screen generated comments from both general 
stakeholders and States. Both were concerned that systems with problems 
could be overlooked in the data sources used by EPA. EPA stated that 
the lists are not static documents and that they can be updated if new 
data are received. For variance technologies, this new data is not 
limited to technology performance. EPA noted that if data are received 
showing violations for contaminants removed by the occurrence screens, 
then EPA would use this data to determine if the system needed a 
variance technology. As was

[[Page 42048]]

previously noted, EPA believes that the results of this analysis would 
be subject to revision based on new information and petitions from 
interested parties.
    <bullet> EPA presented several options for the statutory 
prohibition in Section 1415(e)(6)(A) of the SDWA that was used as one 
of the screens. States preferred the lead option, which was that 
variance technologies might be available for those pre-1986 NPDWRs 
where the MCL was lowered after 1986. This lead option was used in the 
final two-stage screening process for variance technologies.
    <bullet> Some stakeholders questioned whether any relief is being 
provided because the initial screening process left so few contaminants 
eligible for variance technologies. EPA emphasized that variances are 
intended to be the exception and that the goal is to bring as many 
water systems into compliance as possible. EPA also emphasized that the 
same procedures would be used for future regulations and that variance 
technologies might play a larger role in those regulations.
    <bullet> A number of State attendees at both the May 1998 
stakeholder meeting and the July 1997 stakeholder meeting have 
indicated that they did not think there was a need for variance 
technologies for the existing regulations in their State. Ten States 
attended the July 1997 stakeholder meeting and heard the initial 
discussion on variance technologies.
    Another topic discussed at the stakeholder meeting on May 18, 1998 
was the national-level affordability criteria. This topic was broken 
into three parts: an overview, establishment of the baseline, and 
options for the affordability threshold. The comments on this topic 
were concentrated on the development of the baseline and the 
identification of the range of options for national-level affordability 
criteria. The major comments are summarized below:
    <bullet> Baseline values were determined for three parameters: 
annual household water consumption, median household income, and current annual water bills. Stakeholders were asked if separate 
baselines should be established for ground water and surface water 
systems. Stakeholders stated that separate baselines should be 
established, but that the distinction between ground water and surface 
water systems was less significant in small systems because most rely 
on ground water. EPA evaluated the data and determined that there was 
very little distinction between ground water systems and surface water 
systems, so separate baselines were not established.
    <bullet> Stakeholders were asked if there were other mechanisms to 
estimate median household income (MHI) for customers served by small 
water systems. One stakeholder suggested using lower income levels 
instead of the median. EPA stated that the national-level affordability 
criteria should describe the characteristics of typical systems and 
typical households and should not address extreme situations where 
costs might be extremely low or excessively burdensome. The median was 
chosen because it is a measure of central tendency. EPA also noted that 
it did not have data on current water bills and annual household water 
consumption for households with lower income levels. EPA stated that it 
would be inconsistent to use the median values for existing water bills 
and annual consumption with lower income levels.
    <bullet> Stakeholders were also asked if mean or median values for 
the three parameters should be used in establishing the national-level 
affordability criteria. Stakeholders recommended consistency rather 
than a preference for using means or medians. Median values were used 
for all three parameters.
    <bullet> An initial range for the affordability threshold was 
identified at the meeting. This range was from 1.5% to 3% MHI. 
Stakeholders, in general, did not express a strong opinion about where 
the affordability threshold should be set within that range. One State 
offered that 1.5% should be used, since it was the lowest value within 
the range. EPA selected 2.5% based on the rationale described in Part A 
of this Section.
    At the end of the meeting, EPA indicated that it would accept 
comments on the two-stage screening process and the national-level 
affordability criteria through the middle of June. EPA stated that 
comments received by then could be incorporated into the analysis to 
determine their impact. EPA did not receive any comments from 
stakeholders after the meeting on either the screening process or the 
national-level affordability criteria

Dated: July 31, 1998.
J. Charles Fox,
Acting Assistant Administrator, Office of Water Environmental 
Protection Agency.
[FR Doc. 98-21032 Filed 8-5-98; 8:45 am]
BILLING CODE 6560-50-P

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