8.0  END-OF-PIPE TREATMENT	  59

8.1 GENERAL	 59
8.2 WASTEWATER CHARACTERIZATION	 59
8.3 TYPES OF PROCESSES/SYSTEMS EMPLOYED	 60
8.4 END-OF-PIPE TREATMENT CAPITAL COSTS	 61
8.5 END-OF-PIPE TREATMENT OPERATION COSTS	 61
8.6 SLUDGE GENERATION AND DISPOSAL	 61
8.7 AIR POLLUTION CONTROL	 61

9.0  PWB INDUSTRY ENVIRONMENTAL PROBLEMS AND NEEDS	  69
9.1 GENERAL	 69
9.2 ENVIRONMENTAI. AND OCCUPATIONAL HEALTH CHALLENGES	 69
9.3 INFORMATION NEEDS	 69
9.4 SOURCE OF TECHNICAL E^ORMATION	 69
REFERENCES...	  73

APPENDIX  A  (SURVEY   FORM)	   A-l

APPENDIX B  (PROCESS  CHEMICAL DATA)	   B-l

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      Design for the Environment Program
  Economics, Exposure and Technology Division
    Office of Pollution Prevention and Toxics
      U.S. Environmental Protection Agency
            Washington, DC 20460
This document was produced under grant #X 823856-01-0 from
    EPA's Environmental Technology Initiative program.

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                             ACKNOWLEDGMENTS

The authors would like to acknowledge the many individuals and organizations that contributed to
making the project plan a reality, in particular the  Institute  for Interconnecting and Packaging
Electronic Circuits (IPC), Microelectronics and Computer Technology Corporation (MCC), and
the Interconnection Technology Research Institute.

Throughout the project, the PWB DfE Project Core Committee provided guidance, assistance, and
review. Those members of particular note are Kathy Hart (EPA Project Manager), Christopher
Rhodes (IPC), Greg Pitts (MCC), Michael Kerr  (Circuit  Center, Inc.),  John Lott (DuPont
Electronics), Debbie Boger (EPA Technical Workgroup Co-Chair), and Lori Kincaid (University
of Tennessee, Center for Clean Products and Clean Technologies).

A special  thanks is  given  to Christopher  Rhodes and the staff of the IPC  for coordinating the
mailing and receipt of the survey forms.

Of particular value  to this  project were the efforts of the  printed wiring  board industry
representatives that  reviewed drafts of the  survey form or responded  to the  survey.   The
information they provided makes up the majority of this report and  will  serve as the nucleus for a
subsequent study.

This report was prepared by Mark Eelman and George Cushnie of CAI Engineering.

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                         TABLE OF CONTENTS

1.0  DESCRIPTION OF PROJECT	 5

1.1 OVER VIEW OF DFEPWB PROJECT	 5
1.2 PURPOSE OF THE SURVEY	 5
1.3 SURVEY PROCEDURES	 6
1.4 OVERVIEW OF RESULTS	 7

2.0  FACILITY CHARACTERIZATION	 9

2.1 GENERAL	 9
2.2 COMPARISON OF FACILITY SIZES	 9
2.3 GENERAL PROCESS INFORMATION	 9

3.0  PRODUCTION METHODS AND MATERIALS	  17

3.1 GENERAL	 17
3.2 OVERVIEW OF PWB MANUFACTURING PROCESS	 17
3.3 SPECIFIC PWB PRODUCTION STEPS	 19
  3.3.1 Inner-Layer Etchants	 19
  332 Oxide	 20
  3.33 Clean Holes (Desmear)	 20
  33.4 Making Holes Conductive (or Through-Hole Metalizing)	 21
  33.5 Outer-Layer Etch Resist	:	 21
  3.3.6 Outer Layer Etchant	 22
  33.7 Solder Masks	 22
3.4 CHEMICAL USAGE	 22

4.0  WASTEWATER DATA	  33

4.1 GENERAL	 33
4.2 DISCHARGE TYPES	 33
4.3 DISCHARGE FLOW RATES	 33
4.4 DISCHARGE LIMITS AND COMPLIANCE DIFFICULTIES	 34

5.0  POLLUTION  PREVENTION AND WATER CONSERVATION METHODS 39

5.1 GENERAL	 39
5.2 GOOD OPERATING PROCEDURES	 39
5.3 DRAG-OUT REDUCTION AND RECOVERY METHODS	 39
5.4 RINSE WATER USE REDUCTION	 41

6.0  RECYCLE, RECOVERY, AND BATH MAINTENANCE TECHNOLOGIES  47

6.1 GENERAL	 47
6.2 TECHNOLOGIES IN USE BY RESPONDENTS	 47
  6.2.7 Ion Transfer/Porous Pot	 47
  6.2.2 Ion Exchange	 48
  6.2.3 Electro-winning	 48
  6.2.4 Other Technologies	 49

7.0  OFF-SITE RECYCLING	  53

7.1 GENERAL	 53
7.2 OFF-SITE RECYCLING OF SPENT PROCESS BATHS	 53
7.3 WASTEWATER TREATMENT SLUDGE	 54

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 segment, the results will also be very useful to companies that service the PWB industry including
 engineering firms, chemical suppliers, manufacturers/vendors of pollution prevention and control
 equipment, and off-site recycling and disposal sites.


 1.3   Survey Procedures
 The survey  of PWB manufacturing facilities was accomplished using a mailed questionnaire. To
 ensure that the survey adequately addressed the key production processes and pollution prevention
 methods, a draft form was prepared and reviewed by various industry participants, EPA, and other
 interested parties. The questionnaire was then tested by surveying a selected group of five PWB
 facilities.  Based on these responses, the survey  form was revised.  The  final survey form
 (Appendix  A) was then distributed by  IPC to all  IPC PWB manufacturing facility members
 (approximately 400).! The survey form covers eight major areas:

         Facility  and Point  of Contact  Identification.    In order to maintain confiden-
          tiality, this portion of the survey form was kept separate from other portions of the
          form.  Used only in the event that clarification to responses was needed, a procedure
          was employed that prevented anyone from connecting responses to their originator.

         Facility  Characterization.    Requests data concerning facility size, product type,
          base materials used, process capabilities, and technology level.

         Wastewater Discharges.     Requests data concerning the type of discharge (i.e.,
          direct, indirect, zero), flow rates,  discharge  limitations,  compliance problems, and
          costs for water and sewer use.

         Process  Data.  Bequests data concerning various elements of the manufacturing
          process, including etch resist, inner- and outer-layer etching, through-hole metalization,
          oxide, etchback/desinear, solder mask, and chemical usage.

         Recovery,  Recycle, or Bath Maintenance Technology.       Requests  data
          concerning pollution prevention technologies, including costs, savings, labor needs,
          maintenance requirements, residuals generation, and other important information.

         Pollution Prevention  Methods.    Requests  data concerning pollution preven-
          tion (P2) methods used by  the facilities for improving operating procedures, reducing
          water use, preventing the loss of chemicals, and making other improvements.

         End-of-Pipe Treatment.    Requests data concerning the type  of  treatment
          processes used, capital and  operating  costs, sludge  generation,  and  compliance
          problems.

         Identification of  Problems and Needs.   Requests  data  concerning environ-
          mental and occupational health challenges, technology needs, and information needs.
 The methodology employed during the PWB survey project and the format of the questionnaire
employed were based on the  experiences of a similar project conducted for the electroplating
industry by the National Center for Manufacturing Sciences (NCMS) and the National Association
of Metal Finishers during 1993 and 1994 (see reference 1).  Permission to use the survey format
and information gathering  techniques of that study were given by the  NCMS Project Steering
Group.

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                                LIST OF  EXHIBITS
EXHIBIT 2-1.  FACILITY CHARACTERIZATION DATA	  12
EXHIBIT 2-2.  PRODUCT TYPE AND TECHNOLOGY LEVEL DATA	  13
EXHIBIT 2-3.  DISTRIBUTION OF RESPONDENTS BY TECHNOLOGY LEVEL	  14
EXHIBIT 2-4.  DISTRIBUTION OF RESPONDENTS BY BOARD TYPE	  14
EXHIBIT 2 5.  BASE MATERIALS USED FOR RIGID PWB MANUFACTURE	  15
EXHIBIT26.  PROCESS CAPABILITIES OF RESPONDENTS	  16

EXHIBIT 3-1.  OVERVIEW OF RIGID PWB MANUFACTURING PROCESS SEQUENCES	  18
EXHIBIT 3-2.  INNER-LAYER AND OUTER-LAYER ETCHANTS USED BY SURVEY RESPONDENTS	  23
EXHIBIT 3-3.  DISTRIBUTION OF INNER AND OUTER LAYER ETCHANT USE TYPES EMPLOYED BY SURVEY
            RESPONDENTS	 24
EXHIBIT 3-4.  INNER-LAYER COPPER SURFACE PREPARATION DATA	  25
EXHIBIT 3-5.  ETCHBACK AND DESMEAR METHODS DATA	  26
EXHIBIT 3-6.  DISTRIBUTION OF ETCHBACK AND DESMEAJR METHODS EMPLOYED BY SURVEY
            RESPONDENTS	27
EXHIBITS-?.  THROUGH-HOIJEMETALIZING METHODS DATA	  28
EXHIBIT 3-8.  DISTRIBUTION OF THROUGH-HOLE METALEZING METHODS EMPLOYED BY SURVEY
            RESPONDENTS	  29
EXHIBIT 3-9.  OUTER-LAYER ETCH RESISTS DATA	  30
EXHIBIT 3-10. DISTRIBUTION OF OUTER LAYER EFCH RESISTS METHODS EMPLOYED BY SURVEY
            RESPONDENTS	  31
EXHIBIT 3-11. SOLDER MASK DATA	  32

EXHIBIT 4-1.  WATER USE AND WASTEWATER DISCHARGE INFORMATION	  36
EXHIBIT 4-2.  DISCHARGE LIMITATIONS AND COMPLIANCE DIFFICULTIES	  37

EXHIBIT 5-1.  GOOD OPERATING PROCEDURES EMPLOYED BY SURVEY RESPONDENTS	  42
EXHIBITS-!  DRAG-OUT REDUCTION AND RECOVERY METHODS DATA	  42
EXHIBIT 5-3.  DISTRIBUTION OF DRAG-OUT REDUCTION AND RECOVERY METHODS	  43
EXHIBIT 5 4.  RINSE WATER USE REDUCTION METHODS DATA	  43
EXHIBIT5-5.  DISTRIBUTION OF RINSE WATER USE REDUCTION METHODS	  44
EXHIBIT 5-6.  WASTEWATER DISCHARGE REDUCTION ACHIEVED THROUGH POLLUTION PREVENTION	  45

EXHIBIT 6-1.  POLLUTION PREVENTION TECHNOLOGY DATA	  51

EXHIBIT 7-1.  OFF-SITE RECYCLING OF SPENT PROCESS FLUIDS (CONTINUED ON NEST PAGE)	  55
EXHIBIT7-2.  OFF-SITE RECYCUNG/DISPOSAL OF WASTEWATER TREATMENT SLUDGE	  57

EXHIBIT 8-1.  WASTEWATER CHARACTERIZATION DATA	  62
EXHIBIT 8-2.  WASTEWATER TREATMENT EQUIPMENT DATA (CONTINUED ON NEXT PAGE)	  63
EXHIBIT 8-3.  WASTEWATER TREATMENT OPERATING COSTS	  65
EXHIBIT 8-4.  WASTBVATER TREATMENT OPERATING COSTS AS A PERCENTAGE OF SALES VOLUME	  66
EXHIBIT 8-5.  AIR POLLUTION CONTROL DEVICES	  67

EXHIBIT 9 1.  PWB INDUSTRY BsMRONMENTAL AND OCCUPATIONAL HEALTH CHALLENGES	  71
EXHIBIT 9-2.  PWB INDUSTRY INFORMATION NEEDS	  71
EXHIBIT 9 3.  PWB INDUSTRY SOURCES OF TECHNICAL INFORMATION	  72
EXHIBIT 94.  DESIRED MEDIA FOR PRESENTATION OF SURVEY RESULTS	  72

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 very low.  Alternatively, facilities with very low combined water and sewer costs have high
 adjusted production-based flow rates.

 Low water  use rates  ha^e been  achieved  by some survey respondents  through the
 implementation of simple water conservation techniques and/or by using technologies such
 as ion exchange that recycle water.  The lowest production-based flow rate among survey
 respondents  was  achieved  without  the use  of any sophisticated  recycling  technology.
 Rather, they use flow controllers, rinse timers, and reactive or cascade rinsing.  The data
 also indicate  that facilities  that have  implemented the ion exchange technology within their
 processes  have a lower average flow  rate than  those that have  not implemented this
 technology.

 The data indicate that the use of water conservation methods does not always result in low
 water use. The four facilities with the highest production-based flow rates do not use ion
 exchange recycling, but they all indicated that they employ counterflow rinsing, plus some
 other methods of water conservation. In such  cases, it is probable that water is  simply
 being wasted by having unnecessarily high flow rates in their rinse tanks.

 The survey data show that the majority  of the respondents are indirect dischargers (i.e.,
 facilities that discharge process wastewaters to a publicly  owned treatment works or
 POTW).  This is especially true for the  small to mid-sized PWB manufacturing facilities.
 Seventy-seven percent  of all respondents  indicated that  they are indirect  dischargers,

 whereas 94% of the shops with an  annual  production rate below 300,000 board ft2 are
 indirect dischargers.

 The data indicate  that  the majority  of  respondents  (63%) must meet local wastewater
 discharge  limitations that  are more  stringent  than the  Federal standards.  Very  few
 respondents reported any wastewater compliance difficulties.

 One-half of the survey respondents have a formal pollution prevention plan.  Most facilities
 have implemented common pollution prevention methods and procedures.

 Three-quarters of the survey respondents have implemented recycle,  recovery, or bath
 maintenance  technologic s that conserve water and/or prevent pollution.  The most common
 of these technologies is the use of porous pots for maintenance of permanganate desmear,
 ion exchange for water recycle, and electrowinning for metal recovery and reuse. Very few
 advanced  technologies  such as diffusion  dialysis,  membrane electrolysis,  or  solvent
 extraction are used.

 Off-site recycling is a commonly used method for PWB manufacturers to  manage spent
 etchant solutions and wastewater treatment sludges.

 The most common regulated pollutants found in PWB wastewater are copper, lead, nickel,
 silver, and total toxic organics (TTO).

 Two basic  wastewater treatment configurations  are present at the respondent's facilities:
 conventional  metals precipitation and ion exchange systems. Sixty-one percent (61%) of
 the respondents reported having conventional metals precipitation systems.  Thirty-three
percent  (33%)  of  the respondents  reported  using  ion exchange as  their basic  waste
treatment technology and 6.1% installed ion exchange in conjunction  with conventional
metals precipitation units.
                                     8

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                       1.0  DESCRIPTION OF PROJECT
1.1  Overview of DfE PWB  Project
This report presents an analysis  of the results of a pollution prevention and control survey for
printed wiring board (PWB) manufacturers.  The survey was conducted by CAI Engineering, with
assistance from the Institute for Interconnecting and Packaging Electronic Circuits.  The survey
results were analyzed and this report was prepared by CAI Engineering, under a subcontract to
Microelectronics and Computer Technology Corporation.  The Design for the Environment Printed
Wiring Board Project stakeholders provided significant input to the final report.  The work was
funded by grant #X 823856-01-0  under EPA's Environmental Technology Initiative program.

The  DfE PWB project is a voluntary cooperative partnership with EPA,  industry,  and other
interested parties that promotes implementation of environmentally beneficial and economically
feasible alternatives by PWB manufacturers.  The ultimate goal of this project is to help the PWB
industry increase efficiency  and  reduce risk  in  the PWB industry by giving  individual PWB
manufacturers the information they need to make informed decisions that fit their particular needs.
The  initial focus of the project  is  to evaluate  processes or  technologies for "making holes
conductive" (MHC), the process  of depositing a conductive surface in drilled through-holes prior
to electroplating. In support of these efforts, the DfE project is conducting a Cleaner Technologies
Substitutes  Assessment (CTSA) of  several  alternative MHC processes and  tests  are  being
conducted to test the performance of alternative processes. The goal  of the CTSA and testing
phase is to offer a complete picture of the trade-offs between the potential environmental and health
risks, performance, and costs of alternative  processes  so that PWB  manufacturers  can make
informed business decisions that fit their particular situations. The CTSA will focus on alternatives
such as electroless copper, graphite-based, carbon-based, and palladium-based processes.


1.2  Purpose  of the Survey
The pollution prevention and control  survey was performed to gather  and organize information
about the current state of environmental technology and practices for this industry segment. The
focus of the survey was on determining the  types of technologies and alternative processes used,
the extent of their  use, key factors with regard  to implementation, including costs, and their
success and failure rate.  Pollution prevention and control technologies covered by the survey
include substitute raw materials  and  manufacturing processes, reuse and recycle technologies,
procedural changes, and innovative treatment/disposal methods that reduce chemical use or water
use and/or prevent the production of hazardous waste  material and its release to the air, water, or
land.

The  survey results are for the use  of all  those associated with the  printed  wiring  board
manufacturing industry. PWT3 manufacturers can use the results of the survey  to compare their
own manufacturing operations to those  of  the survey respondents.  Using the survey results,
manufacturers can  evaluate how their operations compare in terms of  chemical and  other raw
material usage rates, water use, waste generation, technology level used, and other key factors.
The results  also show  which treatment, recovery and bath maintenance technologies have been
most successful and the costs for purchasing and operating these technologies, trends in chemical
substitution, the identification  of regulated pollutants, sludge generation rates, off-site sludge
recovery and disposal options, and many other pertinent topics. In addition to the manufacturing

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 cost for a single-sided board is $0.58, while the average cost for a multi-layer board is about $22
 (ref. 2). Among respondents, the most commonly produced board is the double-sided board (see
 Exhibit 2-2 and Exhibit 2-3).  Ninety percent of the respondents reported producing double-sided
 boards, while 63% percent of the respondents reported producing  some single-side  boards and
 87% reported producing at least some multi-layer panels.  Of those  shops performing multi-layer
 manufacturing, the largest percentage of shops (94%) produce 4-6-layer boards.  The number of
 shops producing higher layer counts dropped sharply with increasing layers;  only  two shops
 reported manufacturing any boards with more than 20 layers. In general, the production of higher
 layer boards is performed more by the larger production shops (> 500,000 ft2/yr) than the smaller
 ones.  One major exception is respondent 6710.

 Another method of comparing PWB manufacturing processes is variation of substrate type (Exhibit
 2-2 and Exhibit 2-4).  The two basic types of substrates are flexible (sometimes referred to as flex)
 and rigid. Unlike layer count categories where most shops produce at least some single-,  double-
 and multi-layer boards,  shops  typically  manufacture PWBs  using rigid  or  flex  substrates.
 Although the flex  and rigid  manufacturing processes are  similar  (base laminates,  multi-layer
 construction,  and surface finishing  are the major areas of divergence),  only one  respondent
 reported manufacturing a significant percentage of both rigid  and flex PWBs (respondent  ID#
 32483, 90% rigid, 10% flex).

 Exclusively rigid manufacturers are most common among survey respondents.   Seventy-nine
 percent of respondents are exclusively rigid board  manufacturers and 10.5% are exclusively non-
 rigid manufacturers.

 A third category of PWB substrate type is rigid/flex combination. These boards consist of rigid
 and flex substrates that are bonded together to form three-dimensional PWB structures. They are
 often referred to as rigid/flex boards.  Rigid/flex combinations are manufactured by 13.2% of
 respondents.  Only one predominantly rigid  manufacturer reported producing  any rigid/flex
 combinations (ID# T3,1 % of total ft2). All other rigid/flex producers are flex manufacturers.2

 In addition to the respondent discussed previously (ID# 32483), three other shops produce both
 rigid and flex boards, but their production is overwhelmingly either rigid or flex (ID# 25503- 5%
 rigid, 95% non-rigid;  ID# T3: 98% rigid, 2%  non-rigid; and ID# 273701: 98% rigid 2% non-
 rigid).

 Survey recipients were asked to provide current data on base laminate material used in  their PWB
 manufacturing. The responses to this question are presented in Exhibit 2-5. Among base materials
 used for  rigid PWBs,  FR-4  systems  (epoxy  resin  with a  woven  glass  laminate surface)
 predominate.  Ninety-seven percent of respondents reported manufacturing PWBs on FR-4  or
 multi-functional FR-4  substrates.  Among exclusively rigid manufacturers, cyanate ester is used by
 8.8%, PTFE (polytetrafluroroethylene) by 14.7%, and polyimide by 29.4% of these shops.  CEM
 material, usually reserved for the lower technology single- and  double-sided  PWBs, is used by
 35.3% of the rigid manufacturers.  Among survey respondents, CEM material is used mostly by
 moderate to high production shops that produced single- or double-sided PWBs.  CEM material
 includes CEM-1 (paper-epoxy resin core with woven glass on the laminate surface) and CEM-3
 (epoxy resin with non-woven glass core and woven glass on the laminate surface).
2 In several of the exhibits subsequently presented in this report, rigid/flex combinations and flex
PWBs are combined under the table heading of "Non-Rigid."
                                           10

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The recipients of the questionnaire were given approximately three weeks to complete and return
the form. An "800 hotline" was established at the outset of the survey to handle recipients'
questions. To increase the response rate, non-respondents were contacted by fax communications
at the end of the three week response period and given additional time to complete the form.

Recipients of the questionnaire were clearly notified that all information and data that they supplied
in survey form are confidential and that any use or publication of the data will not identify the name
or location of the respondent company or the individual completing the form.  The source of each
response is not known by CA[ Engineering or other project participants.

Most of the data collected during this project are summarized in tables presented in this report.  The
basic repository for the storage and use of questionnaire respondent raw data is  a  database
developed using a commercial  software package (Microsoft Access).  The database  file  is
available to the public in its native format, and utilization therefore requires a licensed copy of the
original program.

Some  tables presented  in this report contain the names of manufacturers and/or commercial
products or  services used by respondents of the survey.  Mention of companies or commercial
products or services is not intended to constitute endorsement for use.


1.4   Overview of Results
The  survey  form was mailed to  approximately 400 PWB manufacturing sites (there are  a total  of
approximately 750 in the U.S.).  A total of 40 responses were received (i.e., 10% response rate).
Based on dollar sales,  the 40 responses represent approximately 17% of the total U.S. PWB
production (ref. 2).

This report  organizes and presents  the  majority of the data collected during  the PWB  survey
project;  however,  it does not contain  an  exhaustive evaluation  of  those data.   The detailed
evaluation of the date will be: conducted in  a subsequent project and the results will be published
separately.

The following are some important findings from the survey:

      The  survey respondents  span the range of PWB facilities found  in the U.S. in terms  of
       production rates, but  are more representative of the mid-  to larger-sized facilities.  This
       circumstance should l)e considered with any use or interpretation of the data.

       Based on  the survey  results, it is apparent that the electroless copper  process is still
       entrenched as the predominate  method  of making holes conductive.   Eighty-six (86%)
       percent of  the survey respondents are still using electroless copper on all or  nearly all  of
       their product. Fourteen (14%) percent indicated  they are using palladium-only systems  on
       all of their product and  only one respondent is using the graphite-based  system, while
       another was evaluating it No respondents reported using the carbon-based system and one
       respondent is evaluating an electroless nickel system.

       The range  of water use among respondents is very  large and there is evidence that some
       facilities have significantly better water use practices than other facilities.  One reason for
       high water use  variability among PWB manufacturers appears to be variable water and
        sewer use  charges paid  by the respondents.  A relationship exists between the adjusted
       production-based flow rates and the cost of water and sewer use.  For facilities that have
       very high combined water and sewer costs, the adjusted production-based flow rates are

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                     Exhibit 2-1.   Facility Characterization Data
Respondent
ID
6710
29710
33089
947745
279
32482
36930A
44657
37817
25503
502100
T3
965874
273701
959951
3470
953880
41739
43841
44486
42692
T2
955703
955099
36930
358000
462800
237900
43694
133000
42751
31838
107300
55595
Tl
946587
740500
3023
mean
median
Annual Sales
($/yr)
nr
nr
$1,500,000
2,000,000
2,500,000
2,800,000
3,000,000
3,038,042
3,600,000
4,000,000
4,500,000
6,000,000
6,000,000
7,000,000
7,000,000
7,500,000
9,000,000
9,000,000
11,000,000
14,000,000
15,000,000
16,000,000
16,000,000
16*000,000
17,000,000
ia,ooo,0oo
20,000,000
22,000,000
24,000,000
36,000,000
40,000,000
45,000,000
50,000,000
50,000,000
51,000,000
84,000,000
100,000,000
105,000,000
$23,012,168
$14,500,000
Facility Size
(ft2)
nr
nr
15,000
9,000
15,000
26,500
18,000
22,000
14,000
25,000
37,000
24,000
38,000
22,500
54,000
30,000
30,000
31,800
56,000
36,000
50,000
30,000
112,500
100,000
ITT
36,000
55,000
300,000
42,000
125,000
50,000
300,000
200,000
109,000
70,000
120,000
600,000
190,000
85,523
38,000

Employees
51
500
30
28
40
35
38
40
45
40
65
50
105
80
85
100
100
130
115
150
150
175
150
250
200
nr
210
178
450
366
380
480
350
420
550
500
1,000
830
223
150
Production
(board ft2/yr)
15,000
57,000
200,000
40,000
250,000
75,000
nr
42358
540,000
90,000
60,000
200,000
175,000
280,000
320,000
240,000
180,000
300,000
250,000
nr
360,000
600,000
nr
nr
96,000
500,000
3,750,000
273,000
500,000
600,000
540,000
3,000,000
5,000,000
nr
936,000
1,900,000
1,800,000
2,300,000
771,799
290,000
nr = no response
                                         12

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                   2.0   FACILITY  CHARACTERIZATION
2.1  General
Facility characterization data were  collected that provide  a useful  comparison among survey
respondents and also serve as a means of relating the respondents as  a group to the overall PWB
industry  population.  These  data,  which include measures  of facility size and  production
capabilities and methods, are presented and discussed in this section.


2.2  Comparison of Facility Sizes
Several measures of facility size were employed to help characterize the respondents and compare
them to the overall PWB  industry sector, including:  annual sales in dollars,  square footage of
manufacturing facility, numb>er  of employees, and PWB production  rate measured  in square
footage.  These data are presented in Exhibit 2-1.

In terms of dollar sales, the survey results indicate that the respondents span the range of facilities
found  in this industry sector, but are more representative of the mid- to larger-sized facilities.
Below is a comparison of data from the survey and from a recent IPC industry profile report (ref.
2).


                           % of Companies      % of Companies
       Sales Volume         IPC Industry        PWB  Industry
           $/yr    	       Profile Report        Survey Results
       Under $5 million         75%                    26%
       $5 to $10 million         13%                    18%
       $ 10 to $20 million         6%                    24%
       $20 to $50 million         4%                    18%
       Over $50 million          2%                    11 %


Other measures of facility size  show similar variation among  survey respondents.  The square
footage of manufacturing facilities ranged in size from 9,000 ft2 to  600,000 ft2,  with a median
                9                            9
value of 38,000 ft  and a mean value of 85,230 ft . The number of employees ranged from 28 to
1,000 people with median and mean values of 150 and 223 people. In terms of square footage of
PWB production, responses tanged from 15,000 to 5,000,000 board  ft2 per year, which included
single- and double-sided PWBs as well as multi-layer PWBs.  Relationships between board
production volumes and dollar sales are presented in the IPC industry  profile report (ref. 2).


2.3   General Process  Information
The survey collected  data for numerous process related topics.   Some of the general process
characterization data are discussed in this section.

Printed wiring board production may be categorized is several ways. Layer count is a common
method of categorization because it relates to overall  technology level (i.e., higher layer counts
require more sophisticated technology).  Board price is also related to layer count.  The average

-------
  90
  80
  70
             Exhibit 2-3. Distribution of Respondents by
                         Technology Level
C*
%
I
   10
   0

         CO

4-6 Layer
s
                                                       
                                                       J
                                                       o
     Exhibit 2-4.  Distribution of Respondents by Product Type
7\J
80 -
70 -
a
S 60
f 50 -
* DU
VM
o 40 -
f
S 30
1
20 -
10 -
0 -





















i  : |X::::::-:y:v:-:-:.:-:.:v:vv.:-:-:v:l
Exclusively or Exclusively or Both Rigid and
Predorninently Predominently Rex
Rigid Flex
                              14

-------
                                    common
Process capabilities  in terms  of layer counts  have already been  discussed.   Other
categories of process capabilities include minimum via size (the  smallest hole that is drilled and
plated successfully) and minimum trace width (the smallest feature that can be imaged and etched
successfully). Process capability data are presented in Exhibit 2-6.  Drill equipment generally is
the limiting factor for hole  sizes, whereas  cleanliness, photoresist type, etching practices and
equipment and other less distinct issues determine trace-width capabilities. Respondents reported
rmnimum via capabilities ranging from 0.002 inches (holes of this size  are generally referred to as
"micro-vias") to 0.022 inches in diameter. Trace widths as low as 0.002 inches are produced by
one respondent.  Thirty-eight percent of respondents reported manufacturing trace widths less than
0.005 inches. Traces in the 0.002-0.003 inches range are generally considered  to be the smallest
practical trace width  achievable, with common photo-resists and etchants.

Other data displayed in Exhibit 2-6 relate to  manufacturing process certifications.  Thirty-five
percent of respondents reported that they are MIL-P-55110 certified. MIL-P-55110 is the military
specification covering PWB manufacturing. Seventy-seven percent of the respondents Cheated
that they have achieved or initiated the process of achieving ISO-9000 certification.  ISO-9000 is
an internationally recognized quality standard.  Its applicability is not limited to the PWB industry.
11

-------
                 Exhibit 2-6.   Process Capabilities of Respondents




Responden
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300

Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,0(30
5,000,000
PWB
Type
(% board ft2

Rigid

0
100
100
m
103
103
103
100
103
0
90
5
1O)
100
100
100
98
100
100
100
100
98
100
100
100
IOC*
0
IOC'
100
100
0
100
100
100
100
100
100
100

Non
Rigid
100
0
0
0
0
nr
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0

Process Capabilities

Typica
Via
(mils)
20
7
22
0
14
nr
20
18
25
20
20
18
16
25
18
25
18
18
8
30
25
20
28
18
22
15
18
20
18
18
18
18
14
4
20
14
34
25
Min.
Via
(mils)
8
5
13
8
14
nr
12
8
20
16
12
2
14
15
18
22
6
14
8
18
20
10
13
10
13
12
10
16
10
8
13
10
10
2
12
8
18
18
Typica
Trace
(mils)
8
8
10
6
5
nr
12
8
8
15
8
8
8
10
7
20
7
10
12
12
6
10
10
8
10
7
8
10
5
8
7
8
5
5
8
5
25
8
Min.
Trace
(mils
4
5
6
'3 = 
4
nr
7
5'.'
8
8
3
2
5
8
7
10
3
7
4
8
3
6
5
5
6
5
5
10
3
5
7
3
3
3
4
4
8
5
Maximum layer-count produced during previous year.

Max.
Layers
18
16
8
12
0
nr
10
16
8
14
15
12
18
2
12
2
12
8
16
2
18
6
10
8
6
14
14
2
24
16
24
24 ;
18
20
27
24
3
4


Mil-P
55110
YES
NO
NO
NO
NO
YES
NO
YES
NO
YES
YES
NO
YES
NO
NO
NO
NO
YES
YES
NO
YES
NO
YES
NO
NO
YES
NO
NO
NO
NO
YES
NO
NO
NO
YES
NO
NO
NO


ISO-
90002
YES
YES
YES
YES
YES
NO
YES
YES
YES
YES
YES
NO
YES
YES
YES
NO
YES
YES
YES
NO
YES
YES
NO
NO
YES
YES
YES
NO
YES
YES
YES
NO
YES
YES
YES
YES
YES
YES

A "YES" response indicates only that the company has at least begun to pursue ISO-9000 certification.
nr = no response
                                       16

-------
Exhibit 2-2.  Product Type and Technology Level Data
Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300
Type of PWB Product
(% of board ft2)
Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,003
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
Rigid
0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100
Flex
60
0
0
0
0
0
0
0
0
95
10
85
0
0
0
0
1
0
0
0
0
2
0
0
0
0
100
0
0
0
60
0
0
0
0
0
0
0
Combin-
ation
40
0
0
0
0
0
0
0
0
5
0
10
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
40
0
0
0
0
0
0
0
Technology Level
(% of board ft2)
Single
Sided
0
5
5
0
0
0
5
5
0
50
5
70
0
15
5
20
10
5
10
75
i
5
32
8
3
0
74
80
0
0
4
0
0
0
0
0
100
10
Double
Sided
60
40
60
30
10
5
65
50
60
45
70
20
3
85
55
80
30
8S
50
25
5
70
50
80
62
30
23
20
10
40
60
10
0
10
0
0
0
85
4-6
Layers
20
30
30
60
65
0
28
25
30
0
20
3
70
0
30
0
50
11
24
0
65
25
27
12
35
50
3
0
20
43
5
28
80
65
70
30
0
5
8-12
Layers
18
24
5
10
20
15
2
18
10
5
5
a
25
0
10
0
10
1
15
0
29
0
1
0
0
15
0
0
50
n
25
50
20
20
15
40
0
0
14-20
Layers
2
1 ;
0
0
5
80
0
2
0
0
0
0
2
0
0
0
0
0
1
0
1
0
0
0
0
5
0
0
20
5
5
10
0
5
15
30
0
0
More
than
20
Layers
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
                          13

-------
                            ti,
                           t/a'
E'S
  ft,
                                                 O)

                                                 cr
                                                 0)
                                                CO
  u
                                                 on
                                                 c
                                                 3
                                                 B
                                                 CO

                                                S

                                                CO
                                                  >
                                                5

                                                0)

                                               o
                                               JO

                                               JB

                                               w
      18

-------
         Exhibit 2-5.  Base Materials Used for Rigid PWB Manufacture

Respondent
ID
955099
55595
44486
955703
6710
947745
44657
29710
32482
36930
965874
953S80
33089
T3
3470
43S41
279
237900
273701
41739
959951
42692
358000
37S17
42751
T2
Tl
740500
946587
3023
31838
462SOG
107300
Production
(board ft2
per year)
ra-
nt
nr
nr
15,000
40,000
42,358
57,000
75,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000 i
280,000
300,000
320,000
360,000
500,000
540,000'
540,000'
600,000
936,OOCi
1,800,000
1,900,000
2300,000
3,000,000
3,750,000
5,000,000
Percent
Rigid
100
100
100
100
100
100
100
100
90
100
100
100
100
9$
103
100 !
103
103
98
103
103
100
100
100
100
100
100
100
100
100
100
100
100
Base Materials Used for Rigid PWB Manufacture
(% of board ft2)
CEM
0
0
0
0
0
0
2
0
0
0
0
0
5
5
1
2
25
0
5
1
2
0
0
75
0
0
0
0
0
0
0
BO
15
FR-4
100
90
0
85
0
70
88
100
60
0
100
95
95
0
83
0
75
98
50
80
98
100
70
25
90
40
70
100
50
5
20
20
80
Multi-
functional
0
10
100
15
100
0
5
0
30
96
0
4 i
0
0
0
96
0
2 i
43
10
0
0
30
0
10
60
15
0
40
80
80
0
5
Cyanate
Ester
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
5
0
0
0
PTFE
0
0
0
0
0
0
0
0
5
0
0
0
0
5
0
2
0
0
0
9
0
0
0
0
0
0
0
0
5
0
0
0
0
Poly-
imide
0
0
0
0
0
30
5
0
5
3
0
1
0
5
1
0
0
0
2
0
0
0
0
0
0
0
12
0
5
0
0
0
0
Other
Materials
0
0
0
0
0
0
0
0
0
0
0
0
0
101
152
0
0
0
0
0
0
0
0
0
0
0
I3
0
0
101
0
0
0
nr = no response
 Bendflex
 BT
                                        15

-------
 3.3.2   Oxide
 The oxide step  is also found in the inner-layer image transfer cluster.  The oxide step can be
 eliminated by purchasing "double treated" laminate that is oxide coated by laminate manufacturers.
 Oxiding,  which is employed to enhance  the copper-to-epoxy bond strength of the multi-layer
 panel, is performed in a variety of similar chemistries, usually consisting of sodium hydroxide and
 sodium chlorite.

 Survey data relating to inner-layer surface preparation are presented  in Exhibit  3-4.  These data
 indicate that all shops producing rigid multi-layer boards use the conventional oxide step for at least
 some of their multi-layer product and 13% also purchase double-treated material  for some of their
 product.  Of the three exclusively flex manufacturers, one does not perform the oxide step at all,
 one does not use the oxide step for 98% of multi-layer product, and the third uses double-treated
 material on all  of its  multi-layer product. The oxide  step  is not  typically needed with flex
 manufacturing due to the different materials used.  The  results show that all of the respondents
 who do not use the oxide step are flex manufacturers.


 3.3.3   Clean Holes (Desimear)
 During drilling, drill bits may become heated resulting in melting and  smearing of the epoxy-resin
 base material across the inner-layer copper interface of the hole barrel (a ring of copper  typically
 0.0014 inches thick), which, if not corrected, would lead to a non-conductive circuit.   Smeared
 epoxy-resin (referred to as smear) is not a concern on  single-sided  circuits because there is  no
 inter-connection in the  holes.  Neither is it of major concern on double-sided circuits because the
 copper-to-copper interface extends out of the hole barrel and onto the horizontal surface of the
 PWB, an area that is  not affected  by  smear.   For inner-layers of multi-layer  panels,  the only
 interface with the subsequently plated copper is the portion of the inner-layer circuit residing in the
 hole barrel. If this surface is; covered with smear, no connection  to the plated copper can occur,
 and the PWB will be defective.

 The desmear process is often grouped and sometimes confused with  etchback because similar or
 identical processes can  be used  to perform  both  functions  (by adjusting  dwell times  or
 concentrations). Desmear is simply the removal of smeared epoxy-resin by-products from the
 copper surfaces  within the hole barrel to facilitate the interconnection between inner-layer copper
 and the electroless  copper which is plated next. Etchback is the removal of a significant amount of
 epoxy-resin and glass from the hole barrel itself.  Etchback is performed to expose a greater copper
 surface area which enhances the bond  between the inner-layer copper and subsequent copper
 plating. For most applications, etchback has  become unnecessary and  is usually not performed
 unless specified.  Furthermore, smear is sometimes considered to be simply a product  of poor
 drilling practices, which, if corrected, would  result in no smear and elimination of the  desmear
 process.

 Two distinct methods of desmear currently exist; wet chemical processing is most common, but
plasma etching is seeing increasing use.  With the wet process, sodium or potassium permanganate
 is  the oxidizer  of choice,  replacing the previously used chromic  acid for  health  reasons.
Permanganate alone is a poor glass etchant;  therefore,  if  etchback  is  required, a concentrated
 sulfuric step is necessary.  Oxygen  and carbon tetraflouride are among  the gases used in plasma
etching.
                                           20

-------
            3.0   PRODUCTION METHODS  AND MATERIALS
3.1   General
This section of the report addresses printed wiring board production methods and materials that are
of particular concern with respect to waste generation and pollution prevention and control.  To
assist the reader in relating the survey data to specific production steps, a brief overview of the
PWB manufacturing process is presented.


3.2   Overview  of PWB Manufacturing Process
The most common printed wiring board manufacturing processes are the single-sided, double-
sided, and multi-layer rigid sequences, which are depicted in Exhibit 3-1.  These diagrams show
that the number of process steps increases with the complexity of the product.

The main processes, common to all PWBs, are drilling, and image  transfer, and  electroplating.
Holes are drilled into PWBs (or punched, in the case of paper-based substrates such  as CEM-1) to
provide layer-to-layer interconnection on double-sided and multi-layer circuits.  These holes are
subsequently "plated through" or made conductive by plating copper onto the hole  barrels  (the
vertical, cylindrical surface of the hole). Since most rigid PWB substrates consist of epoxy-resin
and glass, direct electroplating of hole  barrels is not possible since this material will not conduct
electricity.  Therefore, a seed layer or coating of conductive material (usually electroless copper)
must be deposited into the barrels of the  holes before the electrolytic copper plating can occur.
Holes are also drilled into PWBs, including into single-sided boards, to accommodate component
leads that are inserted through the hole and soldered to the board. Holes drilled for this purpose do
not require electroplating.

Image transfer is the process by which an image of a circuit layer is transferred from film, glass or
directly from image data files, to the copper foil of PWB material.  For inner-layers, this includes
the application of a photo-resist  (a photo-sensitive film which also serves  as the etch resist),
imaging, developing, and etching. For outer-layers, image transfer may include the electroplating
of copper, tin, tin-lead, or nickel/gold coatings.

The predominate method of  accomplishing image-transfer and layer-to-layer interconnection  is
called the "subtractive plating process" or simply "print-and-etch." With this process, a uniform
copper foil layer is selectively etched to create a circuit pattern.  Copper foil is an integral part of
PWB base laminate and is applied by PWB manufacturers during the laminate stage or it is bonded
to substrate by laminate makers.

In an alternative process, called additive processing, the manufacturer forms the copper image by
selectively plating electroless copper onto a sensitized substrate (fully  additive) or by plating a thin
layer of electroless copper non-selectively onto  a substrate,  then  applying a photo-resist and
selectively electroplating additional copper onto the circuit areas (semi-additive). The fully additive
process does not require etching  at all; semi-additive processing only requires etching of the thin
electroless copper layer. Additive processing, although attractive in terms of efficiency and waste
reduction, is not a common choice among manufacturers producing the basic or low-cost PWBs.
This is due to the complexity of the process compared with subtractive processing, the electrical
properties of electroless copper deposits, and certain other physical properties of electroless copper
(e.g., the low copper-to-substrate peel strength).
                                             17

-------
The elimination of lead plating has been a goal of many PWB  manufacturers due partly to strict
local discharge limitations.  Tin-lead is plated as an etch resist,  then, on panels  subsequently
processed with solder-mask-over-bare-copper (SMOBC), the tin-lead coat is promptly stripped.
Therefore, when the predominant SMOBC process is specified, tin-lead is easily replaced by tin as
the etch resist of choice. Unfortunately, a minority of PWBs still require tin-lead reflow and these
panels must be processed with a tin-lead etch resist, which is subsequently fused into solder.
Many shops cannot, for economic or other reasons, maintain both tin and tin-lead plating lines and
are thus unable to employ tin-only plating on that portion of their product which is  SMOBC. In
short, the transition from tin-lead plating to tin-only has been slow.

The survey results indicate that 60% of respondents use tin-lead plate for at least a portion of their
production, including 35% that use tin-lead plate for the majority of their work (Exhibits 3-9 and 3-
10). The results also show that 41% avoid the use of tin-lead plating completely.  Dry film is the
predominate resist for 19% of the survey respondents and 38% use dry film as an outer-layer etch
resist on at least a portion of their product.  Forty-three percent of the respondents  indicated that
they employ nickel-gold plate  as an etch resist on some of their  product, although none plated
nickel-gold on more that 20% of their total production.


3.3.6  Outer Layer  Etchant
The choice between cupric chloride and ammoniacal etchants for outer layer etching  is determined
to a large extent by compatibility with the various etch resists employed.  Metallic etch resists are
generally incompatible with cupric chloride,  greatly limiting its use on outer-layers  regardless of
whatever advantages it may offer. Ammoniacal etchant is generally compatible with all etch  resists
and therefore is very common as an outer-layer etch resist. Sulfuric-peroxide is also compatible
with metallic resists.

Only 13% of the survey respondents indicated they use cupric chloride on any outer-layer panels,
while 87% indicated they use ammoniacal etchant exclusively for outer-layers (see etchant data
presented  previously in Exhibits 3-2 and 3-3).  Two respondents (6%) indicated  that they use
sulfuric-peroxide on all outer-layers as an outer-layer etchant.


3.3.7 Solder  Masks
Solder mask application is found in  the surface finish use cluster.  Most PWBs, including nearly
all high-technology circuits, require solder mask.  The survey results show  a very substantial use
of liquid photoimageable masks (LPT). Seventy-six percent of respondents apply LPI to at  least a
portion of their product (Exhibit 3-11).  Thermal masks are used by 74% of the  respondents.
Forty percent use dry film masks on at least some of their product.  A significant percentage of
respondents indicated that they use all three common mask types (26%).


3.4  Chemical  Usage
Chemical usage data were collected  from respondents for their most commonly used chemicals.
These data have been organized according to the process in which they are used and  are presented
in Appendix B. It is anticipated that these data will be used in future projects to aid in determining
cost savings associated with the implementation of pollution prevention options.
                                           22

-------
3.3   Specific PWB  Production  Steps
Each box in Exhibit 3-1 is a logically distinct process or group of processes.  For some of the
boxes, a set of competing processes, or a use-cluster3 exists.  For example, the hole cleaning step
of desmear may be performed with a permanganate based wet chemistry, other less common wet
chemistries, or in a gas-plasma  chamber.  The survey requested data on several use clusters that
may significantly impact pollution prevention and control. Data were collected on etchants, oxide
processes or alternatives,  processes  for making holes conductive,  outer-layer etch resists, and
solder masks.  The responses to these survey questions are discussed in this section.


3.3.1   Inner-Layer  Etchants
Inner-layers are etched during the inner-layer image transfer step of the typical multi-layer rigid
PWB manufacturing sequence.  Image transfer for inner-layers is  accomplished  in a series  of
processes that result in the transfer of a circuit image from film, glass,  or data to the copper foil
layer of PWB base material. Etching is required for all process sequence alternatives that form the
inner-layer image transfer cluster within the predominate subtractive  process.  Panels entering the
etch process have been coated with an etch resist, usually a dry film photo-resist.  The resist layer
selectively protects the circuit areas from etchant whereas the remaining copper foil is etched away.

Historically, ferric  chloride arid chromic  acid  were common  etchants.  Both have  fallen into
disfavor, leaving cupric chloride and ammoniacal etchants as the etchants of choice in the modern
PWB shop.  Ammoniacal etchants  have the distinct  advantage of being  compatible with both
organic (dry film, typically used for inner-layers) etch resists  and  metallic (tin,  tin-lead, gold,
typically used for outer-layers) etch resists, making it the only choice  for shops where two etching
systems are economically or otherwise impractical.  Although on-site  regeneration methods are
available for both materials, cupric chloride etchant is more frequently processed on-site, a major
consideration  when the  volume of  etchant a  PWB shop   requires is  taken into account.
Furthermore, since cupric chloride  is acidic,  no attack on  high-pH-sensitive  dry  film resist
adhesion occurs.  Sulfuric-peroxide  (i.e., sulfuric acid and hydrogen peroxide) is commonly used
as a micro-etchant.  This chemistry was reported in use  by a small percentage of respondents as a
circuit etchant.  Sulfuric-peroxide has much  lower capacity than other etchants (approximately  38
g/1 vs. 150 g/1 Cu or more for ammoniacal and cupric chloride) but is easily regenerated on-site and
is compatible with metallic etch  resists.

The survey results relating to etchants are presented in Exhibits 3-2 and 3-3.  Seventy-eight percent
of the survey respondents use ammoniacal etchant for inner-layer etching, while 22%  use cupric
chloride.   Six  percent indicated  that  they  use sulfuric-peroxide for  inner-layer etching (one
respondent uses both  cupric chloride and  ammoniacal, which is  why the percentages exceed
100%).  As evidenced by the  data, cupric  chloride use is more common  among larger shops.
Thirty-six percent of the shops  above the median production level use cupric chloride  etchant for
inner-layer etching.

Outer-layer etchant use data an; discussed in  Section 3.3.6.
3A use cluster is defined by EPA as a set of chemicals,  processes, or technologies that may
substitute for each other to perform a specific function.  Traditionally, EPA assesses the potential
hazards and exposure scenarios of specific chemicals, generally leaving the evaluation of potential
substitutes as a post-risk assessment consideration.   The use  cluster approach  evaluates or
compares the potential! risk of all substitutes within a given use (ref. 3).
                                            19

-------
Exhibit 3-3. Distribution of Inner- and Outer-Layer Etchant Use
               Employed by Survey Respondents
                                                           C3 Inner-Layer

                                                           M Outer-Layer
Cupric Chloride
Ammoniacal
Other
                              24

-------
The survey results indicate that 59% of the respondents use permanganate desmear exclusively
(Exhibits 3-5 and 3-6).  One respondent uses  a sulfuric-perrnanganate etchback and desmear
process on nearly all of their product.  Plasma etching is employed at 33% of multi-layer shops,
but only 16% use plasma exclusively.  Two respondents, one rigid and one flex manufacturer,
reported they do not desmear the large majority of their product at all.


3.3.4   Making  Holes  Conductive  (or Through-Hole Metalizing)
This use cluster is the focus of considerable attention due to the chemicals employed,  wastes
generated, and overall complexity of the predominant electroless copper process. The function of
the use cluster is to plate a layer of conductive material into the hole barrels, connecting inner-layer
copper with surface copper.  The electroless copper process includes at  least seven or eight
different process solutions and with the accompanying rinse tanks, an electroless copper line (i.e.,
entire sequence of tanks) may include as many as 20 to 25 tanks.  The electroless copper process
presents problems with respect to waste treatment due to the significant concentration of EDTA or
other chelating  agents found in  all electroless copper baths and associated wastewaters.  As a
result, most PWB facilities use special treatment steps to  separate or destroy these compounds.
These treatment steps increase chemical reagent use,  operating costs,  and sludge production.
Furthermore, most electroless copper baths contain significant concentrations of  formaldehyde that
result in air emissions.

Until the late 1980's, no commercially viable alternative for electroless copper existed. However,
recently several alternatives have been developed and are being used extensively by a limited
number of shops.  These alternatives include carbon- or graphite-based, and, palladium-based
processes.  In addition, there are alternatives which use conductive polymers and inks, and one
that is a non-formaldehyde  electroless process. All of the alternative methods  reduce copper
discharges  and eliminate formaldehyde, and most require fewer process baths than electroless
copper. Beyond these similarities, the competing alternatives have little in common.  For example,
one carbon-based system and one graphite-based system require considerable capital investment in
conveyorized equipment, while others can be performed in a batch mode in immersion tanks.

Based on the survey results, it  is apparent that the electroless copper process is  still entrenched as
the predominant method of making holes conductive (Exhibits 3-7 and 3-8).  Eighty-six percent of
the respondents are still using electroless copper on all or nearly all of  their product.   Fourteen
percent (14%) indicated they are using palladium-only processes on all of their product; only one
respondent is using the graphite-based process,  while another was evaluating it. No respondents
reported using  the carbon-based process, and one respondent is evaluating an electroless nickel
process.


3.3.5   Outer-Layer Etch Resist
Outer layer etch resist application is a process found within the outer-layer image transfer cluster.
This cluster is different from other PWB use clusters in that many of the  alternatives that form the
cluster are  not available to the manufacturer as true alternatives. For example, the choice of etch
resist  is  determined  by  economic  considerations,   downstream  processes,  and  end-user
specifications.  If electrolytic gold is specified by the end-user, for example, gold must be plated as
an etch resist.  If gold is not specified, it is almost never considered as an alternative to tin or tin-
lead due to obvious economic considerations (thin electroless gold finishes have been considered
as a replacement  for tin-lead from time-to-time). Therefore, genuine choices  among the cluster
elements are rather limited.
                                            21

-------
                     Exhibit 35. Etchback and Desmear Methods Data

Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300
Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,0(30
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
PWB Type
(% board ft2)
Rigid
0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100
Non-
Rigid
100
0
0
0
0
0
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0
Etchback/Desmear Method
(% of total production)
Permanganate2
0
100
0
100
100
100
0
100
100
0
100
0
80
J
100
1
0
100
0
J
98
100
100
100
100
100
0
1
100
100
0
80
nr
100
99
100
i
100
Sulfuric-
Permanganate3
0
0
100
0
0
0
97
0
0
0
0
0
0
-
0
~
0
0
0
-
0
0
0
0
0
0
0
-
0
0
0
0
nr
0
0
0
-
0
Plasma
100
0
0
0
0
0
3
0
0
100
0
100
20
.
0
.
10
0
100
-
2
0
0
0
0
0
1
.
0
0
100
20
nr
0
0
0
_
0
No
Desmear
0
0
0
0
0
0
0
0
0
0
0
0
0
.
0
_
90
0
0
_
0
0
0
0
0
0
99
_
0
0
0
0
nr
0
0
0
.
0
Other
0
0
0
0
0
0
0
0
0
0
0
0
0
~
0

0
0
0
.
0
0
0
0
0
0
0
,.
0
0
0
0
nr
0
I4
0
_
0
 Shop does not produce any multi-layer PWBs.
 Desmear only.
o
 Concentrated sulfuric acid etchback, permanganate desmear.
 Permanganate etchback and desmear.
nr = no response
                                          26

-------
Exhibit 3-2.  Inner-Layer and Outer-Layer Etchants  Used by Survey Respondents



Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300

Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
PWB Type
(% board ft2)

Rigid

0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100

Non-
Rigid
100
0
0
0
0
0
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0
Inner-Layer Etchant
(% of inner-layer panels'

Cupric
Chloride
0
0
nr
0
0
0
0
0
0
100
0
100
0
2
0
1 :
0
0
0
2
0
0
0
6
0
0
0
^
100
100
0
0
100
100
0
0
2
50 i

Ammo-
niacal
100
100
nr
100
100
100 i
100
100
100
0
0
0
100
-
100
i
100
100
100
-
100
0
100
100
100
100
100
-
0
0
100
100 !
0
0
100
too i
-
50 i

Other

0
0
ra-
ft
0
0
0
0
0
0
1001
0
0
-
0
r
0
0
0
-
0
1001
0
0
0
0
0
.
0
0
0
0
0
0
0
0
-
0
Outer-Layer Etchant
(% of outer- layers)

Cupric
Chloride
0
0
nr
0
0
0
0
0
0
95
0
97
0
0
0
0
0
0
0
100
0
0
0
0
0
0
0
0
0
0
0
0
100
0
0
0
100
0

Ammo-
niacal
100
100
nr
100
100
100
100
100
100
5
0
3
100
100
100
100
100
100
100
0
100
0
100
100
100
100
100
100
100
100
100
100
0
100
100
100
0
100

Other

0
0
nr
0
0
0
0
o
0
0
1001
0
0
0
0
i 0
0
0
0
0
0
100*
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1 Etchant type is sulfuric-peroxide.
2
Shop does not produce any multi-layer PWBs.
nr = no response
                                      23

-------
              Exhibit 3-7.  Through-Hole Metalizing Methods Data

Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300
Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
PWB Type
(% board ft2)
Rigid
0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100
Non-
Rigid
100
0
0
0
0
0
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0
Through-Hole Metalizing Method
(% of total production)
Electro-
less Cu
100
100
100
100
100
100
100
100
0
100
99
9?
100
100
100
100
100
100
0
0
100
100
100
100
100
100
0
0
100
100
100
99
nr
100
100
100
1
100
Palladium
-only
0
0
0
0
0
0
0
0
100
0
0
s
0
0
0
0
0
0
0
100
0
0
0
0
0
0
100
100
0
0
0
0
nr
0
0
0
-
0
Carbon
-based
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
nr
0
0
0
-
0
Graphite
-based
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
100
0
0
0
0
0
0
0
0
0
0
0
0
0
nr
0
0
o
-
0
Electro-
less Ni
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
nr
0
0
0'
-
0
Other
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
nr
0
0
0
-
0
 Shop produces only single-sided PWBs.
nr = no response
                                       28

-------
            Exhibit 3-4.  Inner-Layer Copper  Surface  Preparation  Data

Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300

Production
(board ft2 per
year)
nr
rar
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,iOOO
500,000
500,000
540,000
540,1300
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
PWB Type
(% board ft2)
Rigid
0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100
Non-
Rigid
100
0
0
0
0
0
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0
Inner-Layer Copper Surface
Preparation Method
(% of total production)
Red, Brown,
Black Oxide
2
100
nr
100
100
100
100
100
100
0
100
0
95
^i
100
1
90
100
100
i
100
100
100
5
100
100
0
1
90
100
15
100
nr
95
99
100 j
i
100
Double Treat
0
0
nr
0
0
0
0
0
0
100
0
0
5

0
,
10
0
0
.
0
0
0
95
0
0
0
,
0
0
0
0
nr
5
1
0
_
0
No Oxide
98
0
nr
0
0
0
0
0
0
0
0
100
0
_
0
_
0
0
0

0
0
0
0
0
0
100

0
0
0
0
nr
0
0
0
_
0
 Shop does not produce any multi-layer PWBs.
nr = no response
                                       25

-------
                   Exhibit 3-9.  Outer-Layer Etch Resists Data

Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
53089
T3
3470
43841
279 ;
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300
Production
(board ft2 per
year)
nr
iff
nr
nr
nr
15,000
40,000
42358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
3(60,000
500,000
5iOO,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
PWB Type
(% board ft2)
Rigid
0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100
Non-
Rigid
100
0
0
0
0
0
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0
Etch Resist Type
(% of outer layers)
Tin
0
33
0
100
0
0
0
0
100
0
90
1
96
85
0
0 !
0
75
0
0
0
50
0
65
95
9S
0
0
80
100
0
0
0
94
0
0
0
98
Tin-
Lead
95
67
0
0
0
100
95
95
0
5
5
2
2
0
100
95
80
10
85
0
100
45
0
35
5
0
0
0
0
0
95
99
0
1
100
0
0
0
Dry
Film
0
0
0
0
100
0
2
0
0
95
0
96
0
15
0
: 5 '
10
10
10
65
0
0
100
0
0
0
100
2
0
0
0
0
100
0
0
0
0
0
Nickel-
Gold
5
0
0
0
0
0
3
5
0
0
5
1
2
0
0
0
10
5
5
0
0
5
0
0
0
2
0
0
20
0
5
1
0
5
0
0
0
2
Other Resist
Type
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
351
0
0
0
0
0
0
0
98*
0
0
0
0
0
0
0
0
1001
0
 Screened ink.
2 SES-R (liquid polymer).
nr = no response
                                        30

-------
Exhibit 3-6. Distribution of Etchback and Desmear Methods
           Employed by Survey Respondents
ou -
70 -\
60 -
3 ""
1
S 50
&
Q
K
<4-i 40
g ^U

f
e ^0 -
^ 20 -
10 -
n


















Permanganate
only




Sulfuric and
Permanganate










Plasma Do Not Other
Desmear
                          27

-------
                         Exhibit 3-11.  Solder Mask Data

Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300
Production
(board ft2 per
year)
nr
nr
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175.000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500.000
500,000
540,000
540,000
600.000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
PWB Type
(% board ft2)
Rigid
0
100
100
100
100
100
100
100
100
0
90
5
100
100
100
100
98
100
100
100
100
98
100
100
100
100
0
100
100
100
0
100
100
100
100
100
100
100
Non-
Rigid
100
0
0
0
0
0
0
0
0
100
10
95
0
0
0
0
2
0
0
0
0
; 2
0
0
0
0
100
0
0
0
100
0
0
0
0
0
0
0
Solder Mask Types
(% of total production)
Thermal
Masks
2
60
90
10
5
10
58
20
0
0
65
0
5
80
40
100
40
50
0
95
1
60
80
70
5
1
0
50
0
0
5
15
nr
0
23
0
5
35
Dry Film
0
1
0
5
15
0
2
0
100
0
0
0
5
0
20
0
5
10
50
0
0
0
0
0
14
0
0
50
0
0
95
5
nr
0
11
0
0
0
LPI1
Screened
98
39
10
m
80
0
40
80
0
0
35
0
90
20
40
0
50
0
50
1 5
99
0
20
30
0
8
0
0
100
40
0
0
nr
15
66
100
95
65
LPI Curtain-
Coated
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5
40
0
0
0
40
0
0
80
90
0
0
0
60
0
80
nr
85
0
0
0
0
1 Liquid photo-imageable.
nr = no response
                                        32

-------
        Exhibit 3-8.  Distribution of Through Hole Metallization Methods

                       Employed by Survey Respondents
  90
   80
   70
I  60


I

8  50
a!
<*->
o

& 40
I  30
o
   20
   10
        Electroless Cu    Pidladium Only
Carbon
Graphite
                                                                     Electroless Ni
                                        29

-------
comparing water use among respondents.  Using this method of comparison, the range of water
use among respondents is smaller than in column 7,  but is still very large (0.90 gal/ssf to 91.2
gal/ssf)4.  This leads to the conclusion that some facilities  have significantly better water use
practices than other facilities.

The high water use variability among PWB manufacturers can be examined by comparing  the
adjusted production-based flow rates (column 8) to other data.  In particular, there appears to be a
relationship between the adjusted production-based flow rates and the cost of water and sewer use.
For facilities that have very high combined water and sewer costs, the adjusted production-based
flow rates are very low.  There are three facilities  with  combined water and sewer costs above
$7.00/1,000 gal (E>#'s 279, 3023,  and 462800) for which there are  adjusted  production-based
flow rate data. The range of flow rates for these three facilities is 0.90 gal/ssf to 2.70 gal/ssf, well
below the median and mean values (8.20 gal/ssf and  12.42 gal/ssf).  Alternatively, facilities with
very low combined water and sewer costs have  high adjusted production-based flow rates.  There
are three facilities with flow rates above 20 gal/ssf for which there are water and sewer cost data.
The range of  combined  water and sewer costs  for these three facilities is  $0.03/1,000  gal  to
$3.00/1,000 gal (the median and mean values for all  facilities providing data are $3.68/1,000  gal
and $5.06/1,000 gal).

Variation  of water and  sewer use  costs among survey respondents is likely due in part  to
geographical location, with higher costs in coastal and arid regions.

Low water use rates can be achieved through the  implementation of  simple water conservation
techniques and/or by using teclinologies such as ion exchange that recycle water.   ID# 462800 has
achieved the lowest production-based flow rate without the  use of any  sophisticated recycling
technology. Rather, they use flow controllers, rinse timers, and reactive or cascade rinsing.   The
data also indicate that facilities that  have implemented the ion exchange technology within their
processes have a lower average flow rate than those that have not implemented this technology.6

The data also indicate that the use of water conservation  methods does not always result in low
water use. The four facilities with the highest production-based flow rates do not use ion exchange
recycling, but they all indicated that they employ counterflow rinsing, plus some other methods of
water conservation.  In such cases, it is probable that water  is simply being wasted by having
unnecessarily  high flow  rates in the  rinse  tanks (e.g.,  flowing water during periods of non-
production).


4.4   Discharge  Limits and Compliance Difficulties
Discharge limitations of  the survey respondents for key pollutants are  shown in  Exhibit 4-2.
Wastewater discharges from printed wiring board manufacturing facilities are regulated by Federal
effluent guidelines at 40 CFR Part 413 or Part 433, depending on  whether  the facility is an
independent printed wiring bozird manufacturer or an integrated facility.  The Federal limitations for
key pollutants are  shown in rows 2 and 3 of Exhibit 4-2.  The data indicate that the majority  of
respondents (63%) must meet discharge limitations that are  more stringent  than  the Federal
4 ssf = surface square feet.
5 Water conservation methods such as these were covered in Section 6 of the PWB survey form.
The responses to these questions are summarized in Section 5 of this report.  Individual responses
can be viewed using the computer database available with this report.
6 Based on six facilities (IDTs 25503,  3470, 43694, 37817, Tl, 31838)  that have installed ion
exchange and have an average adjusted production-based flow rate of 5.4 gal/ssf vs. an average for
all facilities of 12.4 gal/ssf.
                                           34

-------
                           4.0   WASTEWATER  DATA
4.1   General
This  section of the report contains a  discussion  of wastewater  data  provided  by  survey
respondents, including discharge type, flow rates,  discharge limits, compliance difficulties, and
costs for raw water and sewer use charges.  Wastewater treatment methods employed by survey
respondents are covered in Section 8.0.


4.2   Discharge  Types
For  the purpose  of this survey,  the discharge type refers  to  the  destination  of  wastewater
discharges regulated by categorical effluent standards.  The three possible selections in the survey
questionnaire were direct discharge (i.e., to surface  water such  as a river or stream), indirect
discharge (to  a publicly owned treatment  works or POTW), or  zero discharge (no process
wastewater discharge from PWB manufacturing).

The  survey data  (see Exhibit 4-1) show  that the  majority  of the respondents  are indirect
dischargers.  This is especially true for  the small to mid-sized  PWB  manufacturing facilities.
Seventy-seven percent of all respondents indicated that they are indirect dischargers, whereas 94%
of the shops with a production rate below  300,000 board ft2 are indirect dischargers.


4.3   Discharge  Flow Rates
Wastewater discharge data are  summarized in Exhibit 4-1, columns 6 to 9. Average daily flow
rates range from 5,200 gpd (ID# 279) to 400,000 gpd (ID# 740500).  The vast majority of water
used in PWB facilities is used for rinsing.  The quantity of rinse water used is dependent on
numerous factors, including types of boards manufactured, production rate, cost of water and
sewer use, drag-out rate, use of pollution  prevention measures (e.g., extended draining time), the
rinsing configuration (e.g.,  single rinse vs.  counterflow  rinse),  and  water use control method
(e.g., continuously running rinses vs. those controlled  by conductivity controllers). Some of these
factors are examined in this section.

The values in columns 7 and 8 express water use in terms of production.  In column 7, the values
are calculated as the siverage flow rate in  gallons per square feet of production (measured as one
side of finished board). The data in column 7 indicate that the production of double-sided boards
and multi-layer boards require  more rinse water per square feet of production than single-sided
boards.  For example, the lowest flow rate per square foot of board production is achieved by ID#
462800, whose production  is  100% single-sided boards.  The highest  flow per  square foot of
board production  is used by ID# 29710, whose production  is 0% single-sided  boards.   This
relationship is not surprising because the production of double-sided boards and multi-layer boards
require the employment of significantly more processing and rinsing steps.

In column 8, the values are calculated as the average flow rate in gallons per square  feet of "wetted
surface."  The wetted  surface area was calculated based on the total surface area of all layers of
boards manufactured (layer data are given in Exhibit 2-2).  Because these adjusted production-
based flow rates account for multiple processing  and rinsing steps, they are a better means of
                                           33

-------
           Exhibit 4-1.  Water Use and Wastewater Discharge  Information



ID

36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965374
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300


Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
Discharge Type


Direct



X





X










X


X

X






X





X

In-
direct

X
X

X
X
X
X
X

X
X
X
X
X
X
X
X
X
X

X
X

X

X
>:
X
>:
X
>:

X
X
X
X
X



Zero







































Flow for 12-Mth Period

Avg
Flow
(gpd)
27,000
120,000
20,000
100,000
98,000
10,560
1 3,000
6,000
74,000
nr
31,000
5,000
nr
21,000
35,000
I6,tf00
20,000
20,000
38,000
5,200
105,000
25,000
57,125
20,000
100,000
9,000
30,000
6,000
140,000
48,000
160,000
160,000
400,000
200,000
145,000
280,000
26,000
250,000
Median
Mean
Flow
(gal/ft2
of pro-
duction)1
.
-

-

183
84.5
36,8
337.5
-
107.5
14,4
-.
31.2
50.6
20.8
26
21.7
39.5
5.4
100
23.2
49.5
16.25
72.2
4.7
15.6
2.9
67.4
20.8
69.3
44,4
57.7
27.3
16.4
24,3
1.8
13
27.4
51.2
Flow
(gal/
layer
ssf)
-
-
-
-
-
12.0
28.2
8.2
91.2
-
35.8
6.7
-
15.6
13.7
10.4
6.0
9.0
9.7
2.7
15.5
8.4
16.0
6.9
23.7
0.9
7.5
1.4
7.0
4.2
13.6
5.2
9.6
4.3
2.2
2.3
0.9
6.1
8.2
12.4

Max
Flow
gpd
nr
140,000
22,500
130,000
108,000
21,120
18,000
18,000
124,000
nr
54,000
6,500
nr
27,000
45,000
25,000
30,000
30,000
50,000
5,500
125,000
30,000
65,000
30,000
125,000
12,000
40,000
11,000
160,000
62,400
200,000
185,000
1,000,000
250,000
160,000
420,000
31,000
300,000
-
-
Cost of Water and Sewer

Cost of
Water
($/Kgal
0.95
3.10
1.00
1.62
1.70
1.50
1.50
1.98
nr
nr
1.942
nr
nr
1.72
1.33
1.32
nr
O.QO3
3.54
7.56
1.43
1.41
0.80
nr
0.032
nr
1.00
1.20
1.60
1.61
2.73
1.63
2.22
0.58
3.78
1,85
13.80
1.50
1.60
2.19

Cost of
Sewer
($/Kgal
1.45
9.30
24.40
0.79
0.55
3.50
1.50
; 2.29
nr
nr
nr
' nr
nr
1.03
2.60
2.28
4.002
0.06
2.57
5.82
0.61
1.35
1.60
ni
nr
nr
0.78
0.21
3.10
2.70
2.33
2.92
3.08
0.73
5.24
1.90
3.40
1.96
2.29
3.14
Cost of
Water &
Sewer
($/Kgal)
2.40
12.40
25.40
2.41
2.25
5.00
3.00
4.27
_
_
1.94
_
_
2.75
3.93
3.60
4.00
0.06
6.11
13.38
2.04
2.76
2.40
_
0.03
_
1.78
1.41
4.70
4.31
5.06
4.55
5.30
1.31
9.02
3.75
17.20
3.46
3.68
5.06
 Water and sewer costs are combined.
3 Well water.
nr=no response
                                          36

-------
standards. One respondent reported having limitations higher than the Federal limitations.7   The
most stringent limitations reported for each of the key pollutants are:  0.25 mg/1 Cu (max), 0.05
mg/1 Pb (avg), 0.04 mg/1 Ni (avg), 0.01 mg/1 Ag (avg), 0.01 mg/1 CN (avg), and 0.58 mg/1 TTO
(max).

Very few respondents reported any wastewater compliance difficulties (identified by bold type in
Exhibit 4-2).   Of the respondents that reported difficulties, 11% reported difficulties with lead,
8% with copper, and 3% with silver.  A large majority of respondents (86%) did not report any
compliance difficulties.  The  majority of those reporting compliance difficulties have discharge
limitations lower than Federal standards, but in each case, those limitations are not the lowest
limitations imposed on respondents.
7 A limit of 5.0 mg/1 Cu was reported by one respondent. It is assumed that the actual limit for this
facility is no higher than the applicable Federal limitation.
8 Although confidentiality was ensured, some respondents may have avoided listing any compliance
difficulties do to the sensitivity of the subject.
                                           35

-------
38

-------
          Exhibit 4-2.   Discharge  Limitations and  Compliance  Difficulties
Respondent
ID
4
4

t TI
i^FI
6710
*
*

36930A i

36930

273701
358000
955703

33089

107300
502100
44657




43694
29710
T3
Tl




955099

37817

959951
947745

95880

42751



32482
44486
42692



41739



43841
T2
3470



740500 :


279
3023


237900
133000

25503

946587
462800


31838
55595


965874
Cu
max
mg/1
4.5
3.3*
4.50
2,59
4.34
338
2.00
3,00
3.38
2,00
1.00
3,00
3.00
0.49
2.70
1,00
1.50
5.00
3.22
3,38
0.25
3,00
3.38
4.50
4.50
4.00
4.30
2,20
1.50
3.38
3.00
1,50
2.70
1.50
3.00
3,40
2.90
3.00
nr
338
Ou
ave
mg/1
2.7
2, ft?
0.37
1.59
2.60
2.07
1.50
2,07
2.07
1.00
1.50
2.07
2.07
0.41
2.70
0,03
-
3.50
0.45
2,07
-
2.07
2.07
2.70
2.70
0.40
2.60
2,07
2.07
1.70
2.02
-
1.00
-
2.07
-
1.91
1.50
nr
2,07
Pb
max
mg/1
n.*
m.fiQ
0.60
0,53 i
0.58
0,69
-
0,69
0.69
030
-
0,60
0.69
0,43
0.40
0,20
0.20
1,00
0.60
0,69
0.19
0,69
0.69
0,60
0.60
0.60
0.57
0,69
0.20
0,69
-
0.20
0.40
034
0.69
0,50
0.39
0,69
nr
0,69
Pb
avg
mg/1
K4
f .43
0.10
033
0.39
0.43
-
0,43
0.43
0.10
-
0.40
0.43
0.27
0.40
0.05
-
0.25
0.11
0.43
-
0.43
0.43
0,40
0.40
0,30
0.36
0.43
0.23
0.40
-
-
0.40
-
0.43
-
0.26
0.43
nr
0.43
Ni
max
mg/1
4,1
3,98
4.10
3,05
3.95
3,98
-
3,98
3.98
1,30
-
2.20
3.98
2,50
2.60
1,00
1.00
-
2.91
3,98
0.60
2,50
3.98
4,10
4.10
4,00
0.72
3,00
1.00
3.98
-
1.00
2.60
4,10
3.98
2,20
2.64
3,00
nr
3,98
Ni
avg
mg/1
2.6 .
2.3*
0.09
1,83
2.91
23&
-
238
2.38
1.00
-
-
2.38
1,50
2.60
0,04
-
*
0.43
238
-
238
2.38
2.60
2.60
0,50
0.23
238
2.38
1,60
-
-
0.25
*
2.38
-
1.69
1,50
nr
238
Ag
max
mg/1
1.2
0.43
1.20
033
1.16
0.43
-
0.43
0.43
-
-
0.43
0.43
0.02
0.70
0.50
2.00
^
0.85
0.43
0.13
1.00
0.43
5.80
-
LOO
0.03
0,43
0.43
0.43
-
2.00
0.70
0.23
0.43
0.80
-
0,43
nr
0.43
Ag
avg
mg/1
1.7
(24
0.01
OJ8
0.67
0,24
-
0,24
0.24
<+
-
0,24
0.24
0.02
0.70
0.01
-
*4
0.12
0,24
-
H-
0.24
-
1.90
-
0.01
0,24
0.24
0,24
-
*
0.70
-
0.24
*
-
0,24
nr
0,24
CN
max
mg/1
J-VJL
1,20
1.90
032
1.83
1,20
-
1.20
1.20
^
-
1.20
1.20
0.76
1.00
-
1.00
-
1.90
UO
0.74
1.20
1.20
1.90
1.00
1,00
1.82
$.00
0.50
1.20
-
0.50
0.50
0.60
1.20
0.40
1.23
0.80
nr
1.20
CN
avg
mg/1
1,0
0,65
0.01
0,50
0.96
*
-
0,65
0.65
+
-
0,65
0.65
0,41
-
-
-
-
0.17
0,65
-
0,65
0.65
1,00
-
0,01
0.96
0,65
0.65
0,65
-
-
0.50
-
0.65
-
0.65
0,40
nr
0,65
TTO
max
mg/1
2.15
?.,r
2.13
1,63
2.05
-
-
0.58
2.13
2.13
-
2,13
0.58
1.34
2.13
235
5.00
*
2.13
2,13
0.74
2.13
-
1.30
2.13
- \
2.13
2,13
2.13
2.13
-
1.00
2.13
2.13
0.58
-
1.40
2.13
nr
2,13
TTO
avg
mg/1
.
.
.
v
-
+
-

-
*
-
-
-
-
-
1.00
-

-
^
-
i*
-
*
2.13
-
-
-
-
-
-
-
-
-
-
-
-
-
nr
-
Bold type indicates compliance difficulty with discharge parameter.
nr = no response
40 CFR 413 maximum is based on a 4 day average concentration.
40 CFR 433 maximum is based on a monthly average concentration.
                                             37

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 the part is directly related to the quantity of drag-out and other factors.9  When the quantity of drag-
 out is reduced or the drag-out is recovered and reused, the overall quantity of pollution from a
 facility is reduced.  A summary of respondent data relating to drag-out reduction and recovery
 methods employed at PWB manufacturing facilities and plating shops is presented in Exhibit 5-2
 The use of several key methods by PWB manufacturers and plating shops is compared graphically
 in Exhibit 5-3.

 In general, the survey results indicate that PWB manufacturers more frequently control the motion
 of the parts (e.g., slow withdrawal from tank and long drip tanks) as a means of reducing drag-out
 than either adjusting the bath chemistry, adjusting the solution temperature, or employing drag-out
 recovery. Plating shops tend to rely more on drag-out recovery than other methods of reducing
 drag-out losses and  also make  significant  efforts to control process  chemistry  and  bath
 temperature.

 In part, the variance found in the results of the two surveys with regard to drag-out reduction may
 be due to differences in the shapes of the parts being processed, the permissible latitude in process
 control,  and differences in  bath temperatures. The flat surfaces of PWBs improve the performance
 of control methods for drag-out reduction as compared to the range of part shapes  processed by
 plating shops.  For example, pafts with flat surfaces, like PWBs, will more completely drain when
 held for an extended lime  period as compared to a cup-shaped plated part with internal surfaces
 (e.g.,  auto bumper).  Although many plating processes require close chemical  control, there are
 some  (e.g.,  chrome plating) that can be operated over a significant range of  concentrations of
 constituents.  By reducing the chemical concentration of the bath, platers are able to reduce bath
 viscosity and in turn, reduce drag-out. PWB manufacturers  may have less latitude with regard to
 varying the bath concentration. Increasing bath temperature is another means of reducing viscosity
 used to a moderate extent  by plating  shops.  In general, there are a smaller percentage of heated
 process tanks in PWB. shops than in plating shops and therefore less opportunity to take advantage
 of this method of reducing drag-out.  Heated process tanks  in PWB facilities where this  method
 may apply include cleaners, peimanganate desmear, and micro-etches.

 The most common  method of drag-out recovery employed  in the plating industry  is the use of
 drag-out tanks.  Drag-out tank:? are initially filled with clean water and are situated immediately
 after process baths. Parts exiting process tanks are immediately rinsed in the drag-out tank.  The
 contents of the drag-out tank, the initial water and process fluid dragged out by racks and parts, is
 used to replace evaporate  loss in the preceding process tank.  Drip tanks  (a less  sophisticated
 method of drag-out recovery) are not initially filled with water. They are simply a tank over which
 racks are hung to drip.  The contents of drip tanks are returned to the process tank.  Both of these
 methods require that the process tank is heated  in order to evaporate water from the process tank
 and  therefore make "head-room" for the returned solution.  As  such, drag-out and drip tanks are
 only applicable to heated process solutions. Only 34.2% of the PWB survey respondents indicated
 they use  drag-out  tanks  and only  10.5%  use drip tanks,  compared to 80.5% and  33 6%
 respectively,  from the plating shop survey.  The  low use of drag-out tanks in PWB shops is
 possibly due to the permissible latitude in process control and differences in bath temperatures as
 discussed above. However, some PWB heated process  tanks (cleaners, permanganate, micro-
 etches) do lend themselves  to the use of drag-out tanks for drag-out recovery.


5.4  Rinse  Water Use  Reduction
The vast majority of wastewater generated at PWB facilities is the result of rinsing.  A summary of
respondent data relating to  rinse water use reduction methods  employed at PWB manufacturing

9 A detailed discussion of drag-out and rinse water requirements is presented in reference 1.
                                            40

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  5.0   POLLUTION  PREVENTION AND WATER  CONSERVATION
                                     METHODS
5./  General
Respondents were given a check list in the survey form that contained various pollution prevention
methods and procedures  that are known  to be  commonly  used by  printed  wiring  board
manufacturers and were asked to indicate which ones are employed at their facilities (see Appendix
A, sections 6.1, 6.2,  and 6.3). The  lists were prepared  using methods identified  during the
NCMS/NAMF  study (ref. 1) and through the procedures, including industry review, used to
develop the PWB survey form.  The pollution prevention methods  listed in the survey form are
grouped into  three categories: (1)  good operating procedures; (2) methods to reduce or recover
drag-out; and (3) methods to reduce water usage.   Space was provided to allow entry of other
methods, practices, or procedures which were not listed  and a  separate section was included to
permit respondents to describe any innovative pollution prevention practices.  The responses to
these questions  are summariajd  and discussed in this section. Where appropriate, the results are
compared to those of the NCMS/NAMF survey.

Data presented in this section are aggregated rather than presented on a facility by facility basis.
Responses from individual facilities can be found in the electronic database that accompanies this
report.


5.2   Good  Operating  Procedures
Pollution  prevention  methods  listed  under  good  operating  procedures  include various
administrative and equipment related topics that can affect waste generation. The survey results for
this category  are shown in E)diibit 5-1.  Fifty percent of the respondents indicated that they have
established a formal pollution prevention program. This result closely matches the NCMS/NAMF
survey  results of plating shops (ref.  1).  Similarly, close results were  found  with regard to
conducting employee education for pollution prevention (68.4% for PWB shops vs 68.2% for
plating  shops).  In general, the PWB facilities make more frequent use than plating shops of
pollution prevention methods that relate to chemical inventory, process bath control,  and  use of
chemicals. For example, nearly all of the PWB  manufacturing respondents  indicated that they
perform in-house bath analyses  and maintain  records of this work.  This percentage is noticeably
higher than for the plating shops.  Other areas where the PWB shops have a higher percentage of
application of methods as compared to plating shops includes preventative maintenance of racks
and tanks and use of overflow alarms  and leak detection. Surprisingly, only 26.3% of the PWB
shops indicated that they employ statistical process control (SPC) for bath maintenance. SPC is  a
potential cost reduction and pollution prevention method that relates to analytical work and record
keeping, practices employed by  most of these facilities.


5.3   Drag-out Reduction and Recovery Methods
Drag-out is the clinging film of process solution covering a part when it is removed from  a tank.
This solution is usually small in  volume and high in chemical concentration.  The primary purpose
of rinsing is to sufficiently remove the  drag-out from the part so that the part's surface is relatively
free of process chemicals.  Rinsing is necessary to clean the surface of  the part and to prevent
contaminating subsequent process baths.  The quantity of rinse  water needed to sufficiently clean
                                            39

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     Exhibit  5-1.  Good Ojperating Procedures Employed by Survey  Respondents
Drag-Out Reduction or Recovery Method
Perform in-house regular process bath analysis
Maintain records of analysis and additions
Dump process baths based on analysis rather than schedules
Have preventive maintenance program for tanks
Perform regular maintenance and performance checks for racks
Have overflow alarms in process tanks
Control inventory levels and access
Conduct employee education for pollution prevention
Look for opportunities to reduce energy consumption
Have a formal policy statement regarding pollution prevention
Have a formal pollution prevention program
Have a leak detection system
Employ statistical process controls for chemical adds
Recycle non-contact cooling water1
No. of PWB
Respondents
Using
Method
37
37
35
35
32
31
30
26
24
20
19
16
10
1
% of PWB
Respondents
Using
Method
97.4
97.4
92.1
92.1
84.2
81.6
78.9
68.4
63.2
52.6
50.0
42.1
26.3
2.6
% of Plating
Shops Using
Method2
92 1
85.8
73.6
58.2
65.1
15.7
65.1
68.2

49.7
50.6
14.8


  Added by respondent under "Other."
 2 Results published in reference 1.
 - Indicates that method was not listed in that particular survey and not added by any respondents.

            Exhibit 5-2.  Drag-Out  Reduction and  Recovery  Methods  Data
Drag-Out Reduction or Recovery Method
Allow for long drip times over process tanks
Have drip shields between process and rinse tanks
Practice slow rack withdrawal from process tanks
Use drag-in/drag-out rinse tank arrangements
Use drag-out tanks and return contents to process baths
Use wetting agents to lower viscosity
Use air-knives to remove drag-out
Use drip tanks and return contents to process baths
Use fog or spray rinses over heated process baths
Operate at lowest permissible chemical concentrations
Operate at highest permissible temperatures
No. of PWB
Respondents
Using
Method
29
23
20
13
13
12
10
4
4
3
2
% of PWB
Respondents
Using Method
76.3
60.5
52.6
34.2
34.2
31.6
26.3
10.5
10.5
7.9
5.2
% of Plating
Shops Using
Method1
60.42
56.9
38.12
20.82
61. 02
32.4
2.22
27. 02
18.92
34.6
17.9
1 Results published in reference 1.
2 Data are for manually operated methods, which are the predominant type for the plating operations surveyed during
 the NCMS/NAMF project.                    -
                                             42

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facilities and plating shops is presented in Exhibit  5-4.  The use of several key rinse water
reduction methods used by PWB manufacturers  and plating shops is compared  graphically in
Exhibit 5-5.

For both types of shops, the primary means of rinse water use reduction is counterflow rinsing. A
counterflow rinse is a series of two or more rinse tanks piped together in a manner that clean water
enters the final tank of the series and flows into the next tank in a direction opposite that of the
work flow. Far less water is required to maintain  sufficiently clean water in the system than with
a single rinse tank. Eighty-one percent of PWB shops employ this method of water use reduction.
This is a higher percentage than for plating shops  (68.2%).  Flow  controllers, which can be used
in conjunction with counterflow  rinsing, are also very common in  PWB shops (78.9%  compared
to 69.8% in plating shops).  Automated water use  controllers  (i.e., conductivity/pH or timer types)
are also more common in PWB shops than in plating shops. Three respondents indicated that they
use  "part sensors" to  reduce; water use.    Part  sensors  are used primarily  on  conveyorized
equipment to turn on the water flow when a PWB reaches the  rinse module, then automatically turn
off the flow until the next part arrives. The fact  that rinse water  control devices were  generally
more common in PWB than plating shops is likely a result of stricter  rinse criteria (i.e., a more
pure rinse water requirement) for PWB manufacturing than for typical plating. Rinse water purity
requirements are discussed in reference 1.

Exhibit 5-6 presents a summary of rinse  water  reduction  achieved by PWB  facilities through
pollution prevention efforts,  thirty-four percent (34%) of  the shops responding  to the survey
reported that they reduced rinse water  consumption since 1990.   Eleven percent (11%) reduced
their water use by more than half, while 16% reduced water use by one-third or more.   However,
the majority of shops; did not report any rinse water use reduction.
                                            41

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  Exhibit 5-5. Distribution of Rinse Water Use Reduction Methods
                                                               E3PWB Shops

                                                               H Plating Shops
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                              44

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                    Exhibit 5-3. Distribution of Drag-Out Reduction
                                 and Recovery Methods
    180

    M70

    I  60

    1  50
    c
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      30
    60 ^
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              Exhibit 5-4.   Rinse Water Use Reduction Methods  Data
Drag-Out Reduction or Recovery
Method
Use counterflow rinses
Use flow controllers
Use spray rinses
Track water use with flow meters
Reactive or cascade rinsing
Use rinse timers
Recycle or reuse rinse water
Use conductivity or pH controllers
 	 	  c  ; 	 ~" 	 !
Use part sensors to activate nnse
Use squeeze rollers to remove water1
Use spring-loaded valves to activate rinse1
No. of PWB
Respondents
Using Method
31
30
27
25
20
19
11
10
4
1
1
% of PWB
Respondents Using
Method
81.2
78.9
71.1
65.7
52.6
50.0
28.9
26.3
10.5
2.6
2.6
% of Plating
Shops Using
Method2
68.2
69.8
39.0
11.6
23.9
11.3
-
16.0
-
-

  Added by respondent under "Other."
2 Results published in reference 1.
-- Indicates that method was not listed in that particular survey and not added by any respondents.
                                           43

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46

-------
   Exhibit 5-6.  Wastewater Discharge Reduction Achieved Through Pollution
                                  Prevention
Respondent ID
36930A
$55099
55595
. 44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965&74
953880
330S9
T3
3470
43841
279
237900
273701
41739
959951
42692
358GGO
43694
37&17
42751
T2
133000
Tl
740500
946587
3023
31&38
462800
107300
Production
(board ft2 per year)
nr
nr
nr
nr
nr
15,000
40,000
42358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,COO
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
Current Average
Discharge
(gal/day)
27,000
120,000
20,000
100,000
98,000
10,560
13,000
6,000
74,000
nr
31,000
5,000
nr
21,000
35,000
16,000
20,000
20,000
38,000
5,200
105,000
25,000
57,125
20,000
100,000
9,000
30,000
6,000
140,000
48,000
160,000
160,000
400,000
200,000
145,000
280,000
26,000
250,000
Discharge
Reduction
(gal/day)
0
0
0
0
0
2,500
0
3,000
0
150
0
7,000
60,000
0
10,000
3,200 j
0
3,000
50,000
0
0
0
5,000
0
0
0
28,000
0
0
0
0
180,000
0
0
0
0
0
200,000
Jase Year for
Reduction
-
-
-
-
-
1993
-
1994
-
-
-
1993
1993
-
1992
1991
-
1994
1987
-
-
-
1993
-
-
-
1990
-
-
-
-
1991
-
-
-
-
-
1993
nr = no response
                                       45

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 6.2.2   Ion Exchange
 Ion exchange  is a versatile technology that  is  applied by  PWB manufacturers  for  various
 sometimes overlapping  purposes,   including:   chemical  recovery,  water  recycle,  solution
 maintenance, and waste treatment.   For example, twenty-six percent  (26%) of the respondents
 reported using ion exchange as a water recycle/chemical recovery technology.  Many  of these
 respondents reported the same; system as a component of their waste treatment system.  Therefore,
 in some cases it is difficult to distinguish one function from another. In  general, most of the waste
 streams discharged from the PWB process are compatible with ion exchange, and many shops  mix
 several similar rinse streams ;and treat them with  a single ion exchange unit (e.g.,  sulfuric  acid
 dips, micro-etch, and copper electroplating rinses are frequently combined).  The ion exchange
 effluent may be discharged and the regenerant processed using electrowinning, thereby making ion
 exchange both an end-of-pipe waste treatment and a component of a metal recovery system.

 Besides the application of ion exchange as a raw water treatment method (i.e., water softening or
 deiomzation of city  water), ion exchange  is most often used  by PWB  shops in one of  two
 configurations.  If wastewater is to be recycled for re-use as rinse water,  both cation and anion
 resins are required and  wastewater passing through the units is completely de-ionized (impurities
 of 10-40 mg/1 usually remain, consisting mostly of carbonates and silicates).  A second strategy is
 to remove only certain cations from the wastewater and discharge the  treated water.  For many
 streams, the only regulated ions are the metallic species (typically, Cu, Ni, and Pb) and these may
 be selectively removed by special cation resins that allow common monovalent species (Na, K) to
 pass through. This cation-only configuration is employed as a stand-alone treatment system (in
 association with electrowinning)  or  as  a polishing  step  for  the effluent of  a conventional
 precipitation system. Multiple columns of resin are common for either  configuration to allow for
 continuous operation (one column regenerates while the other handles the waste stream).

 Ion exchange resin operates by exchanging a H* ion for a cation in the waste stream, or in  the case
 of anion resins,  an OH" ion  for an anion in the waste stream.  When most sites have exchanged
 their base ion, the resin must be regenerated. During the regeneration phase,  an acid is passed
 through the cation resin (a basis is passed through the anion resin) and cations previously removed
 are exchanged for the base H+ ion. Metal ions present in the regenerant (in concentrations of a few
 grams per liter) are commonly removed using electrowinning, or the regenerant may be sent to a
 conventional precipitation treatment system.

 Seventy  percent (70%) of the  respondents  using ion  exchange indicated that they are generally
 satisfied with the technology  and 60% indicated they would purchase the same unit from the same
 vendor if faced with a similar need.  Twenty percent (20%) of the  respondents using ion exchange
 indicated they would not purchase this technology for a similar need in the future.

 Ion exchange capital costs are related to capacity, which is stated in terms of flow rate (typically
 gallons per minute).  The median price paid by respondents  who reported price information was
 $47,500.  The range of capital costs was relatively wide, with the lowest being $5,000  and  the
 highest being $100,000.


 6.2.3   Electrowinning
Electrowinning is a common metal recovery technology employed by PWB  manufacturers to
remove metallic ions from spent process fluids, ion exchange regenerant, and concentrated rinse

 10 Ion exchange is also comonly used to soften or deionize raw water prior to use as rinse water or
for bath make-up. This function of ion exchange is not discussed in this section.
                                           48

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      6.0   RECYCLE,  RECOVERY, AND BATH MAINTENANCE
                                TECHNOLOGIES

6.1  General
One section of the PWB survey form was devoted to gathering information concerning pollution
prevention and recovery technologies that are applied for the purposes of recovering and recycling
chemicals and improving the life-span of process solutions (see Appendix A, Section 5 of the
survey form). Seventy-six percent (76.3%) of the survey respondents completed Section 5 of the
form.  These respondents reported  use  of  a range of technologies,  including ion transfer,
electrowinning, ion exchange, diffusion dialysis, membrane electrolysis, evaporation, and solvent
extraction.   A  summary of  the technology data  is presented in Exhibit 6-1.   The individual
technologies reported in use by the respondents are briefly discussed in this section.  A more in-
depth technical discussion can be found in reference 1.

6.2   Technologies in  Use  by Respondents

6.2.1  Ion  Transfer/Porous Pot
Electrolytic regeneration of permanganate desmear baths using a porous pot (or similar ion transfer
designs) is a pollution prevention technology employed by 32% of all respondents. This relatively
inexpensive  and simple technology is used for bath maintenance (i.e., extending the useful life-
span) of permanganate  desmear baths.   In  the  conventional  permanganate process, the
permanganate ion is reduced by heat and contact with PWBs and is replaced by chemical addition.
Also, during operation of this bath, by-products (including the manganate ion) accumulate in
concentration causing a sludge to form and frequent disposal is necessary.  The porous pot can be
used to maintain a sufficient low concentration of contaminants and thereby reduce the frequency
of disposal.

The common porous pot design consists of a rectifier,  a  ceramic pot that houses a  cathode
(protecting the cathode  from direct  contact with the process solution), and an anode,  which
surrounds the pot and is in direct contact with the bath.  At startup, the pot is immersed into the
bath (with the  top remaining above  the solution, preventing it  from flowing  into the  cathode
compartment) and filled with an electrolyte, usually sodium  hydroxide.   With the bath shielded
from the cathode, the primary reaction that occurs  is the anodic re-oxidation of the manganate ion
back to permanganate.  Using  the porous pot, a  bath-life extension of ten-fold or more can be
realized.

Capital costs for this technology are low and some respondents reported leasing the equipment
from chemical vendors rather than purchasing it.  Of those who did purchase the equipment, the
median price was $900 per unit. The reported installation and operating costs were also low.

Ninety-two  percent (92%) of the respondents who operate ion transfer  units indicated they are
satisfied with the technology.  A somewhat lower percentage of respondents (67%) indicated that
in the future they would buy the same technology from the same vendor if  faced with a similar
situation.
                                           47

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solution.  Diffusion dialysis is a membrane technology that is typically employed to purify acids
(e.g., nitric acid used in tin-lead stripping baths).

Membrane electrolysis is used by one respondent (ID# 946587).  It is  employed as an on-line
regeneration method for cupdc chloride  etchant  The etching by-product,  cuprous  chloride,  is
brought in contact with the anode of the membrane electrolysis unit, where the cuprous ion is re-
oxidized.  At the cathode, copper is removed (in metallic form) from the solution at a rate roughly
equal to the rate at with it is being introduced.  A membrane separates the cathode and anode and
allows the user to control the rate at which copper is removed from the etchant.

The same respondent also reported using  solvent extraction technology for on-site regeneration of
ammoniacal etchant (and drag-out recovery).  With the solvent extraction process,12 spent etchant
containing dissolved copper is mixed with an organic solution containing an organic reagent in a
mixer-settler tank.  Some of the copper'reacts with the organic reagent and forms a chemical
complex which is more soluble in the  organic  phase than  the etchant solution.   The copper
concentration of the etchant solution is thus reduced.  The processed etchant solution is fed through
a carbon filter and returned to the process. The organic reagent is processed  using electrowinning
to recovery the coppier.
12 This description is based on information found in the literature (ref. 4) and may vary from the
system used by the respondent.
                                           50

-------
water (e.g.,  drag-out rinses).  Eighteen percent (18%) of the survey respondents reported using
electrowinning as a recovery technology and 11% reported using electrowinning as part of their
end-of-pipe system (i.e., in conjunction with ion exchange).

An electrowinning unit consists of a rectifier  and a reaction chamber that houses anodes  and
cathodes.  In the simplest design, a series of alternating cathodes and anodes are set in the reaction
chamber and the electrolyte is made to flow past (or through) them.  Metal ions are reduced onto
the cathode.   The  rate at which metal can be recovered from waste  fluids or ion  exchange
regenerant depends on several factors, including the concentration of metal in the electrolyte  (the
higher, the faster), the size of the unit in terms of current  and cathode area, and the predominate
species of metal being recovered.

Other than ion exchange regenerant, electrowinning can be applied to various spent process fluids.
Three respondents indicated that they use this technology to process  spent micro-etchant.  Spent
micro-etchant contains 15 to 30 g/1 (i.e., 1 to 3%) of copper and is created at a relatively high pace
from several process lines.11 A common practice is to reduce remaining persulfate in the spent bath
with  a  reducing agent (e.g.,  sodium bisulfite),  adjust  the pH  to 1-3  and then commence
electrowinning.  Copper recovered by the process is often sold (it is not of sufficient quality to be
reused  in  the   PWB  process), defraying  the overall  cost of  operating  this technology.
Electrowinning is also commonly applied to spent gold solutions, gold drag-out and drip  tanks,
silver-bearing developer and fix solutions, and other copper- or lead-bearing spent solutions (such
as strippers or acid dips). Recovery of precious metals rapidly recovers the cost of electrowinning
equipment, but most PWB shops produce waste gold- or silver-bearing  solutions only in small
quantities.  Solutions containing hydrochloric acid, or the  chlorine ion in  general, are usually not
processed using electrowinning since electrolysis of these fluids can result in the  evolution of
chlorine gas. The concentration of  metal ions in a solution can be  readily reduced below 1 gram
per liter using electrowinning, ;ind lower concentrations (as low as 1 mg/1) are possible with some
electrolytes. However, the efficiency of the electrowinning process (i.e.,  mass of metal removed
per unit consumption of energy) steadily decreases as the metal ion concentration is depleted.

Eighty-nine percent (89%) of  the respondents that have employed electrowinning as a recovery
technology were generally satisfied with their unit.  A lower percentage (63%) indicated they will
buy the same technology from the same vendor if faced  with a similar decision in the future.
Thirty-eight  percent (38%) indicated they will not purchase  electrowinning  at all in the future if
faced with a similar need.

Electrowinning capital costs are dependent on  the capacity  of the unit, which is rated by most
vendors in terms of current (maximum amperage range of common units  is 20-1,000 amps DC),
              ^
cathode area (ft), and/or metal recovery capacity (Ib/day). The median cost of the units for which
data were provided was $15,(XX).


6.2.4   Other  Technologies
No other technology was reported in use by more than one respondent.  One respondent (ID#
133000) cited use of evaporation, which was  employed to  recover copper sulfate electroplating
solution. One respondent reported using diffusion dialysis for bath maintenance on a tin-lead strip
11 Electrowinning can be performed on either sulfuric-peroxide or potassium persulfate; however
another simple recovery method-cooling-is available for sulfuric-peroxide, which may be more
efficient.
                                            49

-------
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                                          51

-------
example, the facility may have replaced their tin-lead plating bath with a tin-only solution or needed
to dispose of a bath due to irreversible contamination.

Micro-etchants are shipped off-site for recovery by only  8% of the respondents.  Spent micro-
etchants typically contain copper concentrations of 15 to 30 g/1 Cu (i.e.,  1.5 to 3.0%  Cu).  Other
respondents reported electrowinning these solutions on-site, or treating them with conventional
precipitation.

Gold- and silver-bearing wastes are sent off-site by 15% of the respondents.  Gold electroplating
baths (usually gold cyanide) have a long life-span, and not surprisingly, the reported volumes were
all 100 gallons or less.  Solutions containing gold may include spent gold electroplating bath, or
the contents of drip or drag-out tanks on the gold plating line. Silver is present in film developing
fluids that may be reclaimed on-site (electrowinned),  shipped off-site for metal reclamation, or
combined with other waste streams and treated conventionally.

Ten percent (10%) of the respondents indicated that spent rack stripping solution is shipped off-
site.  Plating racks are typically coated with  a non-conductive substance to prevent electroplating
from occurring on the rack surface itself. Due to use, this coating may degrade and plating can
accumulate on the rack, especially near the clamps and  contact  points. This unwanted copper
deposit is removed in a stripping solution such as dilute nitric acid. The volume of spent stripping
solution can be significant. Respondent T3 shipped 1,000 gallons of nitric acid rack stripper off-
site at a cost of more than $5 per gallon.  By comparison, this volume is equivalent to 12.5% of the
etch volume shipped by the ssime respondent.


7.3   Wastewater  Treatment Sludge
A very high percentage of respondents (88% of those providing data) indicated that they send their
wastewater treatment sludge  to off-site disposal facilities rather than  to landfills. This percentage
appears to be particularly high when compared to the 31%  of plating shops that use this method for
disposal (based on results presented in ref. 1).

The  average  and median unit costs for  off-site recovery of sludge are $0.48/lb  and $0.21/lb,
respectively.  In general, the lower costs experienced  by some respondents compared to others
were due to larger-size shipments and shorter distances to the recycling sites, both of which reduce
transportation costs. However, in  some cases, differences in unit costs may be the  result of other
factors.  For example, ED#'s  133000 and   953880 ship similar quantities of sludge the  same
distance to the same recycling company.13 The unit cost of the off-site recycling for the two PWB
manufacturers varies significantly ($0.17/lb vs $0.40/lb).  One difference between  the sludges
shipped by these respondents is the percent solids.  ID# 133000 is shipping a much dryer sludge
(60% solids  compared to  35% solids for ID# 953880).   The dryer sludge will have a greater
recovery value. By drying sludges PWB manufacturers can also reduce transportation costs since
drying reduces the volume of the sludge.  The sludge drying technology and its impact on sludge
volume are discussed in reference  1.

A discussion of off-site  recycling,  including  descriptions  of processes used by  recycling
companies, is presented in reference 1.
13 This particular recycling company operates recycling facilities in both Arizona and Pennsylvania.
Due to the confidentiality procedures employed during this project, it is not known if the two PWB
manufacturers discussed send their waste to the same site.
                                           54

-------
                          7.0   OFF-SITE  RECYCLING
7.1   General
Off-site recycling is a commonly used alternative for PWB manufacturers as a means of managing
spent etchant solutions and wastewater treatment sludges.  Widespread implementation of this
option reduces the quantity of wastes being disposed of in landfills. The PWB survey gathered
information regarding the types of wastes sent to off-site recycling firms, quantities, destinations,
and associated costs. These data are presented and discussed in this section.

A summary of data related to off-site recycling of spent process solutions, including etchants, is
presented in Exhibit 7-1.  Nearly all respondents reported using off-site recycling for disposing of
spent process baths. A summary of data related to off-site recycling and disposal of wastewater
treatment sludges is presented in Exhibit 7-2.  Nearly ninety percent (90%) of those who provided
data concerning the destination of their sludges indicated that  they ship the sludges to recycling
facilities rather than landfills.


7.2   Off-site Recycling of Spent Process  Baths
By far, the most commonly reported spent process fluid that is sent off-site for recycling is spent
etchant, particularly spent ammoniacal etchant. Spent ammoniacal etchant is created at a rate of
roughly 1 gallon per 30 surface square feet of inner- and outer-layer panels.  On-site regeneration
of ammoniacal etchant is  not  widespread. One respondent reported installing solvent  extraction
technology for the purpose of on-site regeneration of ammoniacal etchant and copper recovery in
1994 (see Section 6.2,4).  The reason that spent etchant is a popular waste for off-site recycling is
due mostly to its high copper concentration, which is typically  150 g/1 Cu  (i.e., 15% Cu). Etchant
that is sent off-site is processed to recover the copper and regenerate the etchant for reuse. Eighty-
three percent (83%) of the respondents  who completed the off-set recycling section of the survey
reported that they send spent  ammoniacal etchant  off-site for recycling.  Costs associated with
ammoniacal etchant recycling were provided in several different types of units and varied widely,
but in general, it was, clear that etchant recycling represented a major portion of overall recycling
costs.   One respondent (ID# 462800) reported an income from off-site  recycling of their spent
cupric chloride etchant ($26,000 annually).

Waste  products other than etchant are  less frecfuently sent off-site for recycling by the survey
respondents.  The next most commonly shipped waste product is tin and/or tin-lead stripping
solutions. These solutions are listed by 20% of the respondents who completed this section of the
survey form. Like etchant, spent stripping solutions have a high metal concentration that makes it
a viable candidate for recycling. Also, stripping solutions are generated in relatively high volumes,
furthering the economics of off-site recycling.  For example, ID# 44486 reported shipping 49,911
Ib of tin strip  and ID# T2 reported shipping 9,000 Ib of tin stripper).   In comparison,  these
quantities are equivalent to approximately 20% to  30% of their etchant volume sent off-site.

Flux, solder dross  from the hot-air-solder-level process, and other lead-bearing solutions  are
shipped off-site for recycling  by  20% of the respondents.   However,  the quantities of these
materials that are shipped are  relatively small.   One exception was ID# 41739, who reported
shipping 20,000 pounds  of solder bath to an off-site  recovery facility. Tin-lead plating baths
generally have a long life-span (several years) and disposal of the solution is  an unusual  event.
For this reason, it is believed that with this particular case, shipment was a one-time event.  For
                                           53

-------
     Exhibit 7-1  (continued).   Off-site Recycling of Spent Process Solutions
Respondent
ID
358000
358600
462800
462806
462800
462800
502100
$46587
947745
947745
953880
955099
955099
955699
955703
955703
955703
955703
959951
952951
959951
965874
36930A
Tl
Tl
T2
T2
T2
T2
T3
T3
Waste
Description
etchant
tin stripper
spent copper
acid rinse water
copper sludge
spent flux
sludge
D062
etchant
stripper
D002
etchant
CuSO4
solder
etchant
solder oil
tin strip
flux
gold
silver
ammonia
etchant
etchant
gold
ammonical etch
etchant
etchant
tin strip
nitric acid
etchant
nitric acid
Source
etch
tin stripper
etch
etch
etch/microetch
hot air leveling
etch
Cu sulfate plating
etching
rack strip
etch
amnioniacal etch
plating
HASL
etch
HAL solder
tin strip
HAL solder
tab plate
film processor
etch
etch
etching
deep gold
inner/outer etch
Cu chloride etch
ammoniacal etch
tin strip
rack strip
etch
rack strip
Quantity
70,000 gal
1,806 gal
1,419, 393 Ib
349.020 ib
12,8541b
4,406 Ib
1,600 gal
7,560 gal
3,960 gal
l,206lb
15, 000 gal
65 .060 gal
12,000 gal
22,006 Ib
45, 000 gal
1,360 gal
5,000 gal
806 gal
50 gal
250 gal
15, 840 gal
15, 800 gal
4,200 gal
nr
nr
18, 506 gal
33, 000 gal
9,660 gal
660 gal
&i006 gal
1,000 gal
Costs
0.11$/gal
3.l8$/gal
26,000$/yr1
0.65 $/lb
0.00 $/lb
O.l $/lb
nr
O.l2$/lb
0.06$/lb
0.29$/lb
nr
nr
2.00 $/lb
l.lO$/fb1
0.18$/lb
0.40 $/lb
0.37 $/lb
0.40$/lb
nr
nr
nr
0.30 $/g**
nr
nr
nr
3.68$/gai
nr
3.45$/gai
4.09$/gal
nr
5.36$/gal
Name of
Recycle
Company
Old Bridge, NJ
Republic
Phibro Tech
Envirite
Phibro Tech
AKA Industrial
nr
Learonal
Phibro Tech
Eincycle
Phibro Tech
Macdermkl
Phibro Tech
Dexter
Phibro Tech
DK
Phibro Tech
Ramie
Eiectrochemicals
Eiectrochemicals
Phibro Tech
Phibro Tech
Phibro Tech
Learonal "
Phibro Tech
Phibro Tech
Phibro Tech
Encyde.TX
Encycle, TX
S. Cal Chemical
Great West. Chem
Distance
to
Recycle
Company
(miles)
600
260
40
40
55
nr
86
256
250
660
286
400
56
25
20
25
76
nr
nr
nr
660
460
nr
nr
7
7
456
450
16
10
1 Income from recycled process fluid.



nr = no response
                                        56

-------
 Exhibit 7-1.  Off-Site Recycling of Spent Process Fluids (continued on next page)
Respondent
ID
279
279
3023
3470
3470
6710
6710
25503
29710
29710
29710
29710
32482
330S9
33089
36930
36930
37817
37817
37817
37817
41739
41739
41739
42692
42751
42751
43694
43841
43&41
43841
44486
44486
44486
44486
44657
133000
237900
237900
237900
237900
Waste
Description
cupric chloride
cupric chloride
ammoniacal
ammonia etch
gold plate bath
DG01/D002
D002
cupric chloride
D002/D004
F005/D001
D001
DOOl
gold plating
ammoniacal etchanl
tin/lead
etchant
microetch
flux
etchant
resins
acid sludge
D002
F007
D008
ammoniacal etchant
cupric chloride
ammoniacal etchant
ammoniacal etchanf
D002
DOOl
class 55
NH etchant
peroxide/sulfuric
flux
acid Ni
DOG2/D00S
etchant
ammoniacal etchanl
acid
acid
acid
Source
etch
etch rinses
etch
etch
plate
sulfuric/ peroxide
ammoniacal etch
etch
etch
paint
solder wave
hot air solder lev.
gold plate
etch
solder strip
etch
etching/cleaning
hot air leveler
etch
cadines
waste catch drains
anunaniacal etch
gold bath
solder bath
etch
inner layer etch
outer layer etch
etch
etch
oil/glycol
board scrap
Cuetch
tin strip
HAL
Ni plate
etch
etch
etch
nitric solder strip
sold er strip
plating
Quantity
(per year)
11,000 gal
6,000 gal
199,450 gal
18,000 gal
60 gal
440 gal
8,000 gal
2,000 gal
98,000 Ib
1,536 Ib
2,721 Ib
1,4S2 Ib
100 gal
60,000 Ib
6,000 Ib
60,000 gal
6,000 gal
200 gal
23,000 gal
15 ft3
200 gal
17,000 gal
25 gal
20,000 Ib
52,883 gal
83.700 gal
32,050 gal
35,000 gal
13,700 gal
220 gal
38,000 Ib
255,370 Ib
49,911 Ib
32,292 Ib
195 Ib
6,300 gal
40,000 gal
50,000 gal
2,000 gal
1,000 gal
1,400 gal
Available
Cost
Data
5.54$/gal
5.45$/gal
0.50$/gal
nr
nr
l,96$/gal
1.52$/gal
0.25 $/gal
nr
nr
nr
nr
nr
0.29 $/lb. :
0.40 $/lb.
4,000 $/yr j
9,600 $/yr
230$/dram
nr
I60$/drum
230$/drum
l*,060$/yr
3,000$/yr
nr
nr
nr
nr
nr
38,000$/yr
2,000 $/yr
7,000$/yr
nr
18,135$/yr
1 6,000 $/yr
683$/yr
nr
0.20$/gal
0,lO$/gal
4.60$/gal
S.00$/gai i
4.80$/gal
Name of
Recycle
Company
Phibro Tech
PMbro Tech
Macdermid
nr
nr
US Miter Rec.
Phibro Tech
Old Bridge
Macdermid
Safety-Kleen
Safety-Kleen
Safety-Kleen
Advanced Chem
US Filter Rec,
US Filter Rec.
Phibro Tech
nr
Entech Managt
Dexter
Entech Managt.
Entech Managt.
PMbro Tech
Technic
Alpha Metals
Old Bridge
Norris Environ.
Phibro Tech
S. CalChem
Phibro Tech
Safety Kleen
SIMCO
Phibro Tech
Phibro Tech
Hydrile
PhibroTech
HubbaidHall
Macdermid
S. CalChem
Norris
Norris
Norris
Distance
to
Recycle
Company
(miles)
40
40
75
nr
nr
40
350
3,300
768
100
100
100
120
225
225
400
nr
150
nr
150
150
400
800
800
400
1,000
1,200
30
500
1.500
1,000
200
200
90
200
nr
150
370
370
370
370
nr = no response
                                       55

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58

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     Exhibit 7-2.  Off-Site  Recycling/Disposal of Wastewater Treatment  Sludge
Respondent
ID
279
29710
31838
36930
43694
237900
358000
955703
3470
965874
25503
42692
273701
36930A
33089
502100
959951
T2
44486
462800
TJ
41739
107300
740500
55595
42751
133000
947745
3023
946587
955099
32482
44657
953880
43841
6710
37817
T3
Quantity
dbs)
nr
rir
nr
rir
rtr
nr
nr
nr
10,000
5,000
U20Q
200,000
300
181
80,000
3,000
33,190
58,000
nr
12,854
260,000
42,000
400,000
1,700,000
140,000
250,000
160,000
9,600
320,000
308,000
220,000
14,000
8,200
120,000
10,000
18,000
1,000
10,000
Percent
Solids
ni
nr
nr
nr
nr
nr
nr
nr
75
15
95
40
50
50
35
75
50
25
nr
98
80
65
60
36
40
48
60
80
41
53
48
65
30
35
26
nr
95
80
Recycle
or
Dispose
nr
nr
nr
nr
nr
nr
nr
nr
nr
nr
unknown
unknown
J>
D
P
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
Cost
($/yr)2
nr
nr
nr
nr
nr
nr
nr
nr
nr
nr
720
85,000
200
nr
48,000
nr
nr
nr
nr
0
35,000
6,000
60,000
275,000
22,880
39,375
27,000
1,875
68,000
63,150
50,000
4,000
3,000
48,000
7,800
25,000
1,500
20,000
Cost
($/lb) 2
ni
nr
ni
nr
nr
nr
nr
nr
nt
nr
0.60
0.43
0.67
nr
0.60
nr
nr.
nr
nr
0
0.13
0.14
045
0.16
0.16
0.16
0.17
0.20
0.21
0.21
0.23
0.29
0.37
0.40
0.78
1.39
1.50
2.00
Company
nr
nr
nr
nr
nr
nr
nr
nr
nr
nr
Nbrris Env
S. Water Treat. Co
US Biter Rec.
US Filter Rec.
US Filter R*?c.
nr
Cypms Miami
Encycle, TX
Foremen MtaJs
Phibro Tech
Encycle, TX
Encycle, TX
WRC
WRC
EnvirLte
WRC
WRC
Encycle, TX
WRC
WRC
WRC
WRC
WRC
WRC
WRC
WRC
NE Chemical Co
Encycle, TX
Distance to
Site
(miles)
nr
nr
nr
nr
nr
nr
nr
nr
nr
nr
30
300
nr
30
225
nr
nr
450
20
40
1,500
600
222
1,500
400
nr
300
250
375
1,000
500
nr
750
300
500
850
400
1,800
1 Unit is ft3.
 Some variation in costs among respondents may be due to inclusion or omission of analytical fees
(sometimes referred to as material profile fees).

nr = no response
                                         57

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images. Silver is also used at some PWB facilities for electroplating, but less commonly than for
photographic purposes.

Total toxic organics (TTO) were reported in raw wastewater by 20% of the respondents.  The
primary sources of toxic organics are solder mask ink solvents and screen cleaners, certain film
strippers, phototool cleaners, and tape residue removing solvents.


8.3   Types  of Processes/Systems Employed
Exhibit 8-2 summarizes the respondent's wastewater treatment equipment purchase data.  The
primary purpose of the wastewater treatment systems employed is the removal of dissolved metals.
This is accomplished by the respondents through installation of conventional metals precipitation
systems,14 ion exchange-based metals removal systems, and combined precipitation/ion exchange
systems.  The most common lype is conventional  metals precipitation systems, which includes
precipitation units followed by either clarifiers or membrane filters for solids separation.  Sixty-one
percent (61%) of the respondents  reported having  conventional metals precipitation systems
installed.  Polishing filters  are also commonly employed following precipitation/solids separation.
The use of clarifiers is  the predominant method for  separation of precipitated solids from the
wastewater (only 12.1% of the respondents with conventional precipitation  technology reported
using membrane filters).

Thirty-three percent (33%) of the respondents reported using ion exchange as their basic waste
treatment technology and another 6.1% used ion exchange in conjunction with conventional metals
precipitation units. Thirty-six percent (36%) of the ion exchange systems included electrowinning.
The use of ion exchange as a waste treatment technology is more widespread in the PWB industry
than in the plating industry where it is found in  approximately 6% of plating shops (ref. 1).  One
reason ion exchange is more common as an end-of-pipe technology for PWB shops is the limited
number of regulated ionic species present in PWB wastewater.  For most shops, copper, lead, and
nickel (see Section 8.2) are the only metal ions present in significant concentrations, all of which
are amenable to ion exchange. Furthermore, these metals are also easily electrowinned from ion
exchange regeneration solutions, which  makes the ion exchange/electrowinning combination an
effective metal recovery  system for PWB shops.  Shops  using ion exchange tend to be small- to
medium-size with the  median sales level being $7.5  million, compared to $14.5 million  for all
respondents.

Column 8 of Exhibit 8-2 shows the satisfaction ratings given by the respondents for their treatment
system or system component. The ratings are based on a scale of 1 to 5, with 1 being a low level
of satisfaction and 5 being a high level of satisfaction.

Column 9 of Exhibit 8-2 indicates if the  respondent reported that a failure, malfunction, or other
event associated with the end-of-pipe system resulted in a permit exceedance.  Thirty-two percent
(32%) of  the respondents indicated that they  did experience a permit exceedance due to  their
system.  Some respondents reported the nature of the permit exceedance, these included:  pH
(7.9% of all respondents),  Pb (10.5% of all respondents), Cu (10.5%  of all respondents), and Ag
(2.6% of all respondents).
14  Conventional treatment is a series of unit  operations that is commonly installed for  metals
removal by facilities in the metal finishing  and PWB manufacturing industry sectors.   Metals
removal is accomplished using hydroxide precipitation followed by separation of the precipitated
metals.
                                           60

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                       8.0   END-OF-PIPE  TREATMENT
8.1   General
End-of-pipe treatment is, by definition, not pollution prevention.  However, it is an important
aspect of pollution control and it sometimes competes financially with pollution prevention options
when facilities are developing pollution control strategies.  To make informed decisions about
implementing pollution prevention alternatives that include consideration of all applicable costs and
potential savings requires accurate data.  Therefore, the topic of waste treatment was included in
the PWB survey project so that the true costs of treatment could be examined.  The applicable
portion of the  survey form requested respondents to describe the type of waste treatment system
currently in use at their facilities and to  provide  operating  and cost data.   These  data are
summarized and discussed in this section.


8.2   Waste-water Characterization
Data that characterize the respondent's raw wastewater from their PWB processes are presented in
Exhibit 8-1. The data indicate that copper and lead are the most abundant of the regulated metals.
Copper  was reported to be present by  all respondents.  Copper concentrations  in  the  raw
wastewaters ranged from 0.4 mg/1  to greater than  100  mg/1.   Factors affecting the copper
concentration of raw wastewaier may include: the effectiveness of rinse water controls (which will
determine the level of dilution); whether or not process solutions that have relatively high copper
concentrations (e.g., spent acids and micro-etches) are commingled directly with rinse water, the
effectiveness of drag-out reduction and recovery; and the presence of upstream recovery/recycle
technologies, such as ion exchange and electrowinning.

Sixty-two (62%) of the facilities that provided raw wastewater data reported the presence of lead.
Concentrations of lead ranged from less than 1 mg/1 to 20 mg/1.  The primary sources of lead in a
PWB manufacturing process ;are drag-out from the tin-lead electroplating  and stripping operations.
Lead  may  also be introduced in small quantities from reflow or solder-leveling operations.
Respondents not reporting lead in their raw wastewater may remove lead with a recovery/recycle
technology (e.g., ion exchange) upstream, or  may  not  perform lead plating  (or, therefore,
stripping).  Also, possibly due to a higher sensitivity to lead discharges than some other metals,
more aggressive drag-out reduction and recovery methods may be practiced for lead sources.

Forty-eight percent (48%) of the facilities that provided raw wastewater data reported the presence
of nickel.   Nickel concentrations ranged from less than 1 mg/1  to 7.5  mg/1.   The most common
source of nickel in the raw wastewater is nickel electroplating or electroless nickel plating, which
serve as an undercoat for gold. Another common process is the electrolytic nickel-gold plating of
the connector edge ("tab plating") of certain PWBs (e.g., PC expansion cards). Wastewater flows
generated from these  operations may be  small  in  comparison to copper  or tin-lead plating
operations and drag-out from typical nickel-gold tab electroplating process baths is generally low.
Not all PWBs  require tab nickel-gold plating, and few require  full  nickel-gold  (see Exhibit 3-1,
Outer-Layer Etch Resists). For tab plating,  a small portion of the board is actually immersed in the
bath, thereby limiting dragout. Respondents not reporting nickel in their wastestream may perform
little or no nickel plating or aggressively recover nickel dragout.

Sixteen percent (16%) of the facilities that provided raw wastewater data reported the presence of
silver. Only one respondent reported silver in concentrations greater than 1 mg/1. Silver is present
in the photographic developer and fix solutions (and associated rinses) required to create film
                                           59

-------
                  Exhibit 8-1.  Wastewater  Characterization Data

Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
33089
T3
3470
43841
279
237900
273701
41739
959951
42692
358000
43694
37817
42751
T2
133000
Tl
740500
946587
3023
31838
462800
107300

Production
(board ft2 per
year)
nr
W
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200*000
200,000
240,000
250,000
250*000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936*000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
Influent Characterization
Flow
(gpm)
40
83
15
104
70
22
30
6
120
25
2
9
nr
20
30
9
20
nr
55
nr
73
10
50
20
70
30
20
10
100
400
175
135
300
60
100
nr
103
250
TDS
(mg/1)
1200.0
:
60.0
-
-
-
40.0
-
-
40.0
-
-
nr
-
-
;
-
-
100.0
nr
-
300.0
-
-
-
350.0
130.0
-
1200.0
-
-
-
-
-
-
nr
-
-
pH
(mg/1)
8.0
2,0
6.0
4,0
9.0
5.0
6.0
4,0
-
&.0
4.0
5.0
nr
8.0
4.0
3.0
8.0
2.0
6.0
nr
9.0
3.0
4.0
6,0
4.0
8.0
6.0
8,0
3.0
-
3.0
2,0
2.0
2.0
4.0
nr
7.0
4,0
Cu
(mg/1)
1.0
30,0
10.0
nr
0.4
20,0
30.0
7,0
4.0
2.0
65.0
40.0
nr
40,0
57.0
300,0
5.0
75.0
200.0
nr
1.2
50,0
25.0
5.0
17.5
2.0
30.0
3.0
33.0
30,0
60.0
35.0
85.0
40.0
12.5
nr
0.2
80.0
Pb
(mg/1)
0.2
mo
4.5
-.
_
0.9
2.0
1.0
_
.
_
M
nr
*
1.2
20.0
1.0
5.0
11.0
nr
0.3
5.0
4.0
1.0
0.3
*
3.0
-.
3.0
5.0
.
2.0
_
2.0
7.5
nr
0.1
4-
Ni
(mg/1)
0.2
5,0
4.0
.
_
.
2.0
1,0
_

.
:
nr
-
0.1
+
_
5,0
3.0
fir
0.2
5,0
1.0
.
0.1

3.0
.
7.5
2.0
.
4,0
0.2
5.0
.
nr
.
*
Ag
(mg/1)
_
.
4.0
+,
_
.
2.0
*
_

_
_
nr
*
_
~
_
5,0
0.5
nr
_
-
0.1
^
0.1
.
_
^
_
-
_
^
_
.
_
nr
_
-
TTO
(mg/1)
0.5
^
_

.
,.
_
^
_
^
_
.
nr
.
1.0

2.0
*
1.5
nr
_
t.
0.1
.
_
^
_
.
_
^
_

_
.
_
nr
_
-
nr = no response
                                        62

-------
8.4   End-of-Pipe Treatment  Capital Costs
End-of-pipe wastewater treatment capital costs are included in Exhibit 8-2.  Capital costs ranged
from $1.2 million (purchased in 1980 for a flow of 135 gpm) to $4,000 (purchased in 1987 for a 9
gpm flow). For ion exchange systems, costs ranged from $250,000 (purchased in 1987 for a 70
gpm flow) to $40,000 (purchased in 1994 for a 10 gpm flow).


8.5   End-of-Pipe Treatment  Operation Costs
Exhibit 8-3 displays the major operating costs associated with end-of-pipe wastewater treatment.
For the three largest shops (in terms of  sales) that provided data,  these costs represent 0.29%,
0.37% and 0.35% of sales. The data indicate that waste treatment operating costs, as a percentage
of annual sales, are higher for small shops than for large shops. Fourteen percent (14%) of the
shops reporting had costs in excess of 2% of sales with the highest being 3.1%.  All of these
shops had sales near or below the median sales  level for all respondents.  The median cost for
waste treatment as a percentage of annual sales was 0.83%, and the average was 1.02%.  A plot of
waste treatment operating costs as a percentage of sales volume  for all respondents is presented is
Exhibit 8-4.
8.6   Sludge  Generation and Disposal
Wastewater treatment sludge data were presented previously (Exhibit 7-2) and discussed in Section
7.3.  The three largest shops (in terms of production) that provided data generated sludge solids at
a rate of 0.048, 0.003 and 0.057 lb/ft2 of production.  The variation evidently comes, in part,
from product mix.  The  shop generating only 0.003 lb/ft2 is exclusively a single-sided PWB
manufacture, whereas the other two have a product mix of double-sided and multilayer PWBs for
which additional process steps increase waste generation, including sludge production.

Eighty-eight percent (88%) of those responding indicated they recycle their wastewater treatment
sludge.  Costs associated with the disposition of sludge ranged from $2.00/lb to $0.13/lb Annual
costs and unit costs are given in Exhibit 7-2.


8.7   Air Pollution Control
Exactly one-half of the respondents to this survey  have installed air  scrubbers (Exhibit 8-5). The
processes listed most frequently as requiring scrubbers were ammoniacal etching, HASL (hot air
solder leveling), and wet processes in general.
                                           61

-------
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                                                         64

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                                                            63

-------
Exhibit 8-4.  Waste Treatment System Operational Costs
            as a Percentage of Annual Sales
275
^ 2.50 -
CO
-3 2.25 -
c
c
< 2.00^
*S
W) 1 i-l c
as 1.75 -
CD
3 1.50
c
1 1.25 -
U
| 1.00
cd
H 0.75 -
CD
4 >
C
^ 0.50 -
0.25
C

A

A
I A
-4; 	
s
|
*
S
s
1
AA \ A
S;
A "'
A A
A
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^
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0 41








A
A
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3 61










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0 8










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0 1C










'^^if-^-K-SWm-s-ww^:
A 'i
	 ft* 	 f
K) 12
          Annual Sales (Millions of Dollars)
                        66

-------
              Exhibit 8-3.  Wastewater Treatment  Operating Costs


Respondent
ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
T3
33089
3470
43841
279
237900
273701
41739
959951
42692
43694
358000
42751
37817
T2
133000
Tl
740500
946587
3023
31838
462800
107300

Production
(board ft2
per year)
nr
nr
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
Average
Wastewater
Flow
(gpd)
27,000
120,000
20,000
100,000
98,000
10,560
13,000
6,000
74,000
nr
31,000
5,000
nr
21,000
35,000
16,000
20,000
20,000
38,000
5,200
105,000
25,000
57,125
20,000
100,000
9,000
30,000
6,000
140,000
48,000
160,000
160,000
400,000
200,000
145,000
280,000
26,000
250,000

Chemical
Costs
($/yr)
1,600
141,000
nr
nr
15,500
6,768
13,212
6,460
37,444
iff
40,492
2,200
13,100
10,456
96,092
24,185
13,320
4,755
26,674
nr
87,012
11,800
71,374
48,561
172,429
20,320
20,624
nr
6,320
96,250
167,000
167,764
98,000
108,840
124,029
nr
23,875
143,850
Median:
Mean:
Chemical
Costs
($/Kgal
of Flow)
0.23
4.52
-
~
0.61
2.47
3.91
4.14
1.95
:
5.02
1.69
-
1.92
10.56
5.81
2.56
0.01
2.70
-
3.19
l.$2
4.81
9.32
6.63
8.68
2.64
-
0.17
7.71
4.01
4.03
0.94
2.09
3.29
-
3.53
2.21
3.24
5.00

Sludge
Costs
($/yr)
0
50,000
nr
nr
nr
25,000
1,875
3,000
nr
nr
4,000
720
nr
nr
48,000
20,000
48,000
0
7,800
nr
nr
! 200
6,000
nr
85,000
nr
nr
39,375
1,500
nr
27,000
35,000
275,000
63,150
68,000
nr
0
60,000

Routine
O&M
(hrs/yr)
100
20,000
nr
nr
7,000
1,040
780
550
3,552
1,200
2,200
1,200
800
10,000
1,760
<$Q
2,000
2,000
5,100
nr
6,000
3,500
3,120
nr
4,992
4,000
2,500
10,000
550
3,000
6,500
2,080
nr
8,050
6,834
nr
4,000
9,275

Repair
Time
(hrs/yr)
40
300
nr
nr
30
30
50
30
nr
100
100
40
50
100 !
100
240
100
200
100
nr
425
700
100
nr
100
40
250
2,500
45
250
500
500
nr
208
342
nr
150
1,571



Costs
($/Kgal of
Flow)
0.53
15.88
-
-
4.75
17.42
8.15
11.64
4.72
-
9.80
28.09
-
29.66
18.90
13.65
17.85
7.26
11.38
-
6.72
11.54
8.46
-
12.84
34.58
7.93
-
0.46
1L62
7.19
5.80
3.59
5.69
7.95
-
12.74
5.64
9.13
11.41
nr = no response
                                      65

-------
68

-------
                    Exhibit 8-5.   Air Pollution Control Devices
Respondent ID
36930A
955099
55595
44486
955703
6710
947745
44657
29710
502100
32482
25503
36930
965874
953880
T3
33089
5470
43841
279
237900
273701
41739
959951
42692
43694
358000
42751
37817
T2
133000
TI
740500
946587
3023
3I83&
462800
107300
Production
(board ft2 per
year)
nr
nr
nr
nr
nr
15,000
40,000
42,358
57,000
60,000
75,000
90,000
96,000
175,000
180,000
200,000
200,000
240,000
250,000
250,000
273,000
280,000
300,000
320,000
360,000
500,000
500,000
540,000
540,000
600,000
600,000
936,000
1,800,000
1,900,000
2,300,000
3,000,000
3,750,000
5,000,000
Is Air
Scrubber
Installed
no
yes
yes
no
yes
no
no
yes
yes
no
no
yes
no
yes
no
no
no
no
yes
yes
no
yes
yes
yes
no
yes
no
no
no
yes
yes
yes
no
yes
yes
no
no
yes
Processes or Chemicals Requiring
Air Scrubber

HASL^croetehing#lating
plating,chemicalprocessing,solder,screening,coati

ammonical etchant


hoi air level
caustic hot baths, formaldehyde.ammonia from etching


cupric chloride etch, copper plating

plating




ammoniacal etcher


etching, acid vapors, metal roof rust
acids bases and associated wet process chemistries
etching, stripping, |jlating, formaldehyde

wet processes areas




plating, etching, electroless, gold plate, solder strip
all

etch, hydrochloric, sulfmic, nitric acids
etch, permanganate, microetch, plating


ammonical etch
nr = no response
                                        67

-------
The results of the plating shop survey (ref. 1) for a similar question are also presented in Exhibit 9-
3. The platers were given fewer choices, which may have increased the frequency of selection for
individual information sources.  Platers less frequently cited in-house sources, with a particularly
low percentage for in-house engineers (20.0%). This result may be due to the lack of engineers at
the plating shops that participated in the survey (only  5%  of  the respondents indicated that  they
have an engineering department).  Platers may also tend to rely less on other in-house resources
such as chemists and miscellaneous employees than do PWB  shops.  Platers did list consultants,
journals, and conferences with relatively higher frequency than did the PWB shops. Both types of
shops appear to rely heavily on vendors for technical information.

In terms of presentation media, the PWB shops overwhelmingly selected the printed report as then-
choice of media (see  Exhibit 9-4).  Plating shops similarly selected the  printed report.   One
noticeable difference between the two surveys is the high frequency of selection by the platers for
workshops and conferences. This may be due to the fact that this industry has held an annual joint
environmental conference with the U. S. Environmental Protection Agency for the past 16 years.
                                           70

-------
9.0  PWB  INDUSTRY  ENVIRONMENTAL PROBLEMS  AND  NEEDS
9.1   General
Several questions in the PWB survey form were aimed at identifying environmental problems and
needs experienced by the respondents.  The resultant data are summarized and discussed in this
section.


9.2   Environmental and Occupational Health Challenges
Survey recipients were  given a check list of potential environmental and occupational health
challenges that their company may face and asked to indicate all applicable items.  The results arc
summarized in Exhibit 9-1.  Respondents selected the increasing cost of compliance as the  most
pressing  environmental or occupational health challenge  facing their business  (69%).   Other
challenges  that were identified by one-third or more of the  respondents  include:  changing
environmental  regulations (57%);  consistently meeting effluent discharge limits  (42.1%); and
reducing  worker exposure to chemicals (39.4%).  Eliminating  solvent use  was  identified  as  a
challenge by 28.9% of the respondents. Other less frequently cited challenges were inconsistent
enforcement of regulations (18.4%), hazardous waste transportation liabilities (13.2%), meeting
air emission standards (13.2%), and lack of hazardous waste disposal sites (2.6%).

The results of the plating shop survey (ref. 1) for a similar question are also presented in Exhibit 9-
1. The platers were given fewer choices, which may have increased the frequency of selection for
individual challenges. However, the ordering of the three most frequently cited challenges for the
plating survey were identical to those of the PWB survey.


9.3   Information Needs
Survey recipients were given a list of potential information needs to help identify specific areas of
information needs for this industry.  The results are presented in Exhibit 9-2.   Only chemical
recycling was cited by a majority (54%) of respondents as  being a subject for which they desired
more  information.  Other subject areas that were  cited  by one-third or more of the respondents
include: water recycling (44.7%);  fully or semi-additive processing (39.5%); and tin-lead plating
alternatives (36.8%).


9.4   Source of Technical Information
Survey recipients were given lists of potential technical information sources and media that may be
used to distribute information from this project and were asked to indicate the pathways and media
that they presently use. The results are presented in Exhibits 9-3 and 9-4.  All of the information
sources listed were identified as being frequently  used by at least one-fourth of the respondents.
In-house  engineers (78.9%)  and vendors (73.7%)  were the most common  sources of technical
information for PWB shops,  followed by in-house chemists  (55.3%), professional  journals
(52.6%), literature from trade organizations (47.3%), other shops (42.1%), books (42.1%), other
in-house employees (39.5%), conferences (34.2%), and consultants (34.2%).
                                          69

-------
           Exhibit 9-3.   PWB  Industry Sources of Technical Information
Source of Information
In-house Engineer
Vendor
In-house Chemist
Professional Journals
Literature from Trade Organizations
Books
Other Shops, Competitors
Other In-house Employees
Conferences
Consultant
% of PWB
Survey Respondents
Citing Source
78.9
73.7
55.3
52.6
47.3
42.1
42.1
39.5
34.2
26.3
% of Plating
Survey Respondents
Citing Source
20.0
63.6
22.6
66.1
-
51.1
-
4.4
53.6
51.4
- Indicates that item was not listed in the survey form and not added by any respondents.
          Exhibit 9-4.  Desired Media  for  Presentation of Survey  Results
Media Type
Printed Report
On-Disk System for Personal Computer
On-Line System Accessible With Personal
Computer and Modem
CD-ROM for Per;>onal Computer
Workshop or Conference
% of PWB Survey
Respondents
Citing Media Type
89.4
36.8
13.2
13.2
10.5
Ranking by Plating
Survey Respondents
Citing Media Type
1
3
4

2
- Indicates that item was not Listed in the survey form and not added by any respondents.
                                         72

-------
  Exhibit 9-1.  PWB Industry Environmental  and Occupational Health  Challenges
Environmental and Occupational
Health Challenges
Increasing cost of compliance
Frequently changing regulations
Consistently meeting effluent discharge limits
Reducing worker exposure to chemicals
Eliminating solvent use
Inconsistent enforcement of regulations
Meeting air emission standards
Hazardous waste transportation Liabilities
Lack of hazardous waste disposal sites
Worker and management acceptance
Paper work
Amount of analytical work1
% of PWB Survey
Respondents
Citing Challenge
68.4
52.6
42.1
39.4
28.9
18.4
13.2
13.2
2.6
2.6
2.6
2.6
% of Plating Survey
Respondents
Citing Challenge
72.4
54.5
38.2

23.8

23.2
_
17.9
-
-
'
1 Added by respondent under "other." This item may have been more frequently selected if listed in the survey form.
~ Indicates that item was not listed in the survey form and not added by any respondents.
                    Exhibit 9-2.   PWB  Industry Information Needs
Items for Which Available
Information is Insufficient
Chemical Recycling
Water Recycling
Fully or Semi-Additive Processing
Tin-Lead Plating Alternatives
Smear Removal Alternatives
Certified Courses for Pollution Prevention
Electroless Copper Alternatives
Direct Imaging
Air Quality Issues1
Low Cost Water and Chemical Recycling1
Percentage of PWB Survey
Citing Information
Respondents
Need
50.0
44.7
39.5
36.8
28.9
28.9
21.1
10.5
2.6
2.6
1 Added by respondent under "other." This item may have been more frequently selected if listed in the survey form.
                                             71

-------

-------
                                     References
1.     Cushnie,  G.C., Pollution Prevention and Control Technology for Plating  Operations.
       National Center for Manufacturing Sciences, Ann Arbor, MI, February, 1994.

2.     Microelectronics and Computer Technology Corporation and Institute for Interconnecting
       and Packaging Electronic Circuits, "PWB Industry and Use Cluster Profile" (draft), July,
       1995.

3.     U.S. EPA, "Printing Industry and Use Cluster Profile," EPA 744-R-94-003, June, 1994.

4.     Rivera, C. and DeClue, G.,  "Ammoniacal  Etchant Regeneration and Copper Recovery,"
       7th AESF/EPA Conference on Environmental Control for the Surface Finishing Industry,
       January, 1986.
                                          73

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                            Section 1. Facility and Contact Information
1.1 Facility Identification

     Company Name:

         Site Name:

      Street Address:

              Citv:
                                                          State:
Zip:
1.2 Contact Identification
        Enter the names of the persons, who can be contacted regarding this survey.
                                Main Contact
                                                                        Alternate
         Name:

          Title:

         Phone:

          Fax:
                                                      A-2

-------
                      Appendix  A



Pollution Prevention and Control Technology Survey Form
                          A-l

-------
                                  Section 3. Wastewater Data (contd.)

3.2 Discharge Limits and Regulations
         If your facility is regulated with concentration-based limits, enter the effluent limits for your discharge.  Place a
         check mark in the "X" column next to any parameter with which your facility is experiencing compliance difficulty
         and, if time permits, attach a sheet describing the nature of the difficulty.  Please specify "other" parameters.
       Parameter
                 Copper
                   Lead
                 Nickel
                  Silver
          Cyanide (total)
     Cyanide (amenable)
  Daily
maximum
       mg/1
       mg/1
       mg/1
Monthly
Average
                     mg/1
      mg/1

      mg/1

      mg/1
                    mg/1

                    mg/1
                                                              Parameter
                                TTO
                                                                         TSS
                                                         Other:
                                                         Other:
                Other:
                Other:
  Daily
maximum
       mg/1
       mg/1
Monthly
average
                                                                                                     mg/1
                                                                                                     mg/1
                                                                                 m
         Check if facility is regulated with mass-based regulations and attach a sheet listing the limitations
         and indicate the production units employed.  An example of a mass-based limit would be 400 mg of
         copper per square meter of circuit board produced.
                                         Section 4. Process Data

4.1 Process Types
        Estimate the percentage of outer-layers manufactured at your facility on which the following etch resists are
        employed.  Specify "other" entry.
                                                                  Tin
                                                             Tin-lead
                                                             Dry film
                                                    Gold or nickel-gold
                         Other:
                                                             TOTAL
                                                 100   %
        Estimate the percentage of inner- and outer-layers manufactured at your facility with the following etchants.
                 Inner-layer
                                          Outer-layer


Other:

Cupric Chloride
Ammoniacal

TOTAL



100
Cupric Chloride
Ammoniacal
Other:
TOTAL
%
%
%
100 %
                                                        A-4

-------
                                   Section 2.  Facility Characterization

        Estimate manufacturing data for the previous 12 month period or other convenient time period of 12 consecutive
        months (e.g., FY94).  Only consider the portion of the facility dedicated to PWB manufacturing when entering
        employee and facility size data
 2.1 General Information
                     Size of facility (sq ft):
         Approximate number of employees:

                              Total sales:
 Total PWB board sq. footage manufactured:

2.2 Type of Product
(Estimate the percentage of total PWB square footage)

                                  Rigid

                                   Flex
      tyr

      /yr
                    Rigid/Flex combination
                                    Total
                                              100 %
                                                        2.4 Base Materials Used for Rigid PWB Manufacture
                                                        (Estimate the percentage of total rigid sq. footage)
                                                                                             CEM:

                                                                                             FR^:
                                                                    High temp, or multifunctional FR-4:
                                                                                       Cyanate ester:
                                                                                             PTFEs:
                                                                                           Polyimide
                                                            Other
                                                                                             Total:
                                                                                                       100  %
 2.3 Process Capabilities
                            Typical via size:
                          Minimum via size:
                         Typical trace width:
                      Minimum trace width:

         Max. layer count produced last year:

        Company is MIL-P-55110D certified:
    Company has initiated ISO 9000 program:
     mils

     mils

     mils

     mils

     lyrs

yes   no

 yes   no
                                                         2.5 Technology Level
                                                         (Estimate the percentage of total PWB square footage)
                                                                                      Single sided:
                                                                                     Double sided:
                                                                                         4-6 layer:

                                                                                        8-12 layer:
                                                                                       14-20 layer:
                                                                               More than 20 layer :

                                                                                            Total:
                                                                                                       100  %
                                        Section 3.  Wastewater Data
3.1 Discharge type
         See Appendix A for definitions of direct, indirect and zero discharge.
Waste water discharge type (check one) Direct Indirect
Approximate waste water flow for last 12 months (or other 12-month period): Average:
Maximum:
Approximate cost of water
Approximate cost of sewer
Zero
gpd
gpd
S/1000 gallons
S/1000 gallons
                                                          A-3

-------
e
o
o

s
*-

Q
       
                -p
               o
               o
               C
               -o 
                .Si
I1B
al
               S
               z


               i
               t_
               o
               13

               1
               6
       (N

       *
       O-
              2
              OH
                                       A-6

-------
                                    Section 4. Process Data (contd.)
4.1 Process Types (contd.)
         Estimate the percentage of PWBs manufactured at your facility with the following through-hole metallizing
         methods.  Specify "other" entry.
Standard electroless copper (includes light and heavy dep.)
Palladium-only system
Carbon-based system
Graphite-based system
Electroless nickel
Other:
TOTAL
%
%
%
%
%
%
100 %
         Estimate the percentage of inner-layers processed through an oxide process or alternatives.
                          Processed through standard (red, brown or black) oxide line
                                      Use "double-treat" material and do not oxide
                                            Use standard material and do not oxide
                                                                        TOTAL
         Estimate the percentage of multilayer panels manufactured at your facility which are etchback/desmeared as
         follows.  Specify "other" entry.
Permanganate desmear only
Sulfuric etchback/permanganate desmear
Plasma etchback/desmear
No etchback or desmear
Other:
TOTAL
%
%
%
%
%
100 %
         Estimate the percentage of panels manufactured at your facility with the following solder mask types:
Thermal cure (e.g., PC 501, SRI 000)
Dry film
Liquid photoimagable, screened
Liquid photoimagable, curtain-coated
TOTAL
%
%
%
%
TOO %
                                                          A-5

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    Section 5. Recovery, Recycle and Bath Maintenance Technology Data Sheets (contd.)

 5.3 Current Status of Technology

                                                                                 Currently in use:

                                         Not currently in use, no intention of future use (explain below):

                                         Not currently in use, but intend to use in future (explain below):

           Explanation (Include dates and reasons):
5.4 Benefits/Costs
         Check categories of savings or costs realized after implementation of this technology.  If possible,
         quantify the annual savings resulting from this technology .
           Category
                  Water use
        Process chemistry use

        Waste water treatment
                   chemistry
          Sludge disposal cost

                     Energy

                      Labor
              Production rate
   Other:
Saving
Cost
Amount per Year ($)
                                                                                    Comments
5.5 Maintenance
        Describe operational and maintenance problems that you have encountered with this equipment and
        indicate the frequency of their occurrences. If possible, estimate the associated costs or other measure
        of the severity of problems.  Attach additional sheet if necessary.
               What downtime percentage (for problems and routine maintenance) have you experienced"
                                                       A-8

-------
         Section 5. Recovery, Recycle or Bath Maintenance Technology Data Sheets

        Please fill out a copy of Section 5 for each recovery or recycle technology present or previously used at your facility.
        Examples of technologies are ion exchange (for water-recycling or metal recovery), electrowinning, porous pot
        (permanganate regeneration), reverse osmosis and evaporation. End-of-pipe systems are covered in Section 7 and
        should not be entered in this section.

5.1 Technology Identification
                                       Technology Name (e.g., ion exchange):

                     Manufacturer or Vender of technology:
                                    Model number of unit:
                Capacity of unit (indicate units such as gpm)
                      Process line(s) where unit is installed:
                     Process or rinse bath(s) treated by unit:
                 Volume (gallons) of process fluid or rinse water processed daily:
              Typical daily production rate (sq. ft.) passing through treated baths:
S.2  Capital and Operating Cost Data
                Year of Purchase:
   Approximate cost of equipment:
   Approximate cost of installation:
Approximate cost of ancillary equipment:

    Approximate annual operating labor:
    Annual non-labor operating expenses
              (e.g., chemicals, energy):
                                                                                                         hours
         Equipment was purchased from:

            Manufacturer r~L       Manufacturer's Representative PL   Other (specify):
                         KMB                                    H^B
         Indicate the type and number of employee(s) that are involved in operating and maintaining this unit (enter the
         number of empioyees for each type that applies):
           Environmental engineer:
        Process/Chemical engineer:

                        Chemist:

                      Consultant:
Plumber:
Electrician:
Vendor:
Senior plater:

_.._

                           Junior plater or operator:
                         Wastewater plant operator:
                                Trained technician:
                                 Common laborer:
                                                          A-7

-------
    Section 5.  Recovery, Recycle and Bath Maintenance Technology Data Sheets (contd.)
5.8 Flow Characterization

               If available, provide data on the flow coming into the technology

          Chemical or Ion       Concentration  |j   j   Other Parameter
             (Ex.: Cu)         (Indicate Units)
                                            "    TSS

                                                 PH

                                                 Temperature

                                                 Flow rate
                                                                       Value (note units)
                                                                                   mg/1
                                                                                 deg. F

                    __________________ i ____
5.9 Block Diagram
        Please provide a block diagram of the technology and it's incorporation into your process.
                                                           M^^
5.10 Other Comments or Explanation
                                                  A-10

-------
   Section 5.  Recovery, Recycle and Bath Maintenance Technology Data Sheets (contd.)
5.6 Residuals
         Provide data on any residuals generated by this technology (e. g., sludge, concentrated acid):

       Type of residual       Quantity (indicate units such                  Method of Disposal
                                   as gallons/year)




                       Adj$i|fy$ RifflBfljjijiia^itis^iiSi^BiiiitiiM


S.7 Other information

         Check the reason(s) technology was purchased.

                   To meet or help meet eflluent limits           To reduce worker exposure to hazardous chemicals

                  To reduce process chemical purchases                      To reduce process chemical purchases

           To reduce quantity of waste shipmeivts off-site       Other:

                           To increase production rate



         Has the technology satisfied the need for which it was purchased?

                    yes [ ~]|           no    b        partially
                        IRPPlS               USSlfili

         Explain if "no" or "partially.'






         jtomwaaiiHiiBwiiiilillil^^

        Indicate a future course of action, should you be required to fill a similar pollution prevention or control
         need.

      Purchase the same technology from the same vendor:

     Purchase the same technology from a different vendor:            Which vendor:

            Purchase a different technology to satisfy need:        Which technology:

                           Not purchase any technology:
                                                          A-9

-------
                          Section 6. Pollution Prevention Methods (contd.)
 6.4 Pollution Prevention Methods
         Describe any innovative or unusual pollution prevention methods practiced at your facility. Include
         methods that reduce or eliminate chemical use, recycling methods, etc.
6.5 Wastewater Discharge Reduction
         Indicate any reduction in the volume of wastewater discharge, in gallons per day, that was
         achieved through pollution prevention practices (enter "0" for no reduction).
        Baseline year for above volume reduction:
6.6 Offsite Recycling of Spent Process Baths
        Estimate the requested information for wastes such as spent etchants or other process fluids that are sent offsite for
        recycling.
Waste type





Source (the process Qty. (indicate units,
bath or baths) Ibs. or gal. per year)










Costs ($/lbs.)
(transport and
recycle fees)





Name of Recycle
Company





Additional explanations or comments:
Distance
(miles)








                                                      A-12

-------
                                Section 6. Pollution Prevention Methods
         Check the drag-out reduction arid recovery, rinse water use reduction, and general good operating procedures
         presently practiced in your facility.  Please specify "other" entries.
6.1 Drag-out Reduction and Recovery Methods
    Use drag-out rinse tanks and return contents to process baths
             Use drip tanks and return contents to process baths
              Practice slow rack withdrawal from process tanks
                  Allow for long drip times over process tanks
 6.2 Rinse Water Use Reduction
                  Use drag-in/drag-out rinse tank arrangements
              Use fog or spray rinses over heated process baths
                            Use air knives to remove drag-out
             Have drip shields between process and rinse tanks
         Operate at lowest permissible chemistry concentrations
                   Operate at highest permissible temperatures
                         Use wetting agents to lower viscosity
   Other:
6.3 Good Operating Procedures
                   Use countercurrent rinses
                        Use flow controllers
       Use conductivity or pH rinse controllers
                           Use rinse timers
                           Use spray rinses
                 Recycle or reuse rinse water
            Track water use with flow meters
                  Reactive or cascade rinsing
Other:
Other:
                                                                      Does your company:
                                        Have a formal policy statement regarding pollution prevention
                                                        I lave a formal pollution prevention program
                                                Conduct employee education for pollution prevention
                                                                Control inventory levels and access
                                                     Perform in-house regular process bath analyses
                                                         Maintain records of analyses and additions
                                                 1 lave written procedures for make-ups and additions
                                                                Employ reactive or cascade rinsing
                                          Dump process baths based on analysis rather than schedules
                                                   Have a preventive maintenance program for tanks
                                       Perform regular maintenance and performance checks for racks
                                                      Have overflow or other alarms in process tanks
                                                                     Have a leak detection system
                                            Employ statistical process controls for chemical additions
               Other:
               Other
                                                         A-ll

-------
                         Section 7. End-of-Pipe Treatment Systems (contd.)
 7.2 Wastewater Characterization
         Estimate the values for the v/astewater flowing into your end-of-pipe system.
             Flow

             IDS

              pH

              Cu
gpm

mg/1


mg/1
  Pb

  Ni

  Ag

TTO
mg/1

mg/1

rag/1

mg/1
 7.3 Capital Costs of End-of-Pipe System
         Estimate the cost of your basic system and any upgrades or additions (e.g.,  sludge dryer,
         polishing filter) along with a rating of your overall satisfaction with the unit (l=low level of satisfaction,
         5=highest level of satisfaction)
System or Upgrade Year of
Purchase
-- 	  - j- ,-.... - -
Initial System !
j
	 r~ 	 ~ -
*Wffi3ft#ORbH*iffilUft^
Cost
- --
	


Manufacturer
	 	 	 	
1
I
2
..._.. _
W'P1WtHII(BW^
latin
3
B
4
	
5
8K' "WW4'miWitem'Hp:iu
7.4 Chemicals Costs
         Estimate the quantities and costs of chemicals used last year in your end-of-pipe system

            Chemical
                                  Quantity Used
                                  (indicate units)
                   Cost
              (indicate units)
                   Total Annual Costs
                  WWMWMI!M^
7.5 Labor Costs
        Estimate the total hours expended per year lor operation and maintenance of the end-of-pipe system.

                        Total hours per year for routine operation and maintenance:
                                                        Total hours for repair:
                                                      A-14

-------
                             Section 7. End-of-Pipe Treatment Systems
7.1 System diagram
        Please draw a simple block diagram of your end-of-pipe system used for treating your industrial
        wastewater. An example diagram is shown in Appendix B.  If appropriate, you can use the example
        diagram by marking necessary changes. Include incoming flow rates, chemical additions, discharge
        flow rates and sludge data. Attach sheet if necessary.
                                                      A-13

-------
                          Section 8.0. Identification of Problems and Needs

 8.1 Environmental/Occupational Health Challenges
         Check the most pressing env ronmental/oct upational health challenges facing your company.  Check all that apply.
              Lack of hazardous waste disposal sites

       Consistently meeting effluent discharge limiN

                           Eliminating solvent use

                    Frequently changing regulations

             Reducing worker exposure to chemicals
                                                                   Meeting air emission standards

                                                                     Increasing cost of compliance

                                                            Inconsistent enforcement of regulation:
                                                          Hazardous wraste transportation liabilities

                                                      Other:
                                    SafflSi65BPK.

                             Water recycling

                  Smear removal alternatives

      Certified courses for pollution prevention
                                                                          Electroless copper alternatives

                                                                                   'fin-lead alternatives

                                                                           Fully or serni-additive process
                                                             (Mher

                                                             Other
  Check the sources of technical information most frequently used by your employees


                           In-house engineer

                           In-house chemist

                   Other in-house empltnees

                                 Consultant

                                    Vendor ,      Jj     Other:

                               Conferences |      I    ! <, )tlier:
                                                                                                Books

                                                                                   Professional journals

                                                                       iterature from trade organizations

                                                                                Other shops, competitor
                          wrawwiim^              .arm,
                                                         A-16

-------
                          Section 7. End-of-Pipe Treatment Systems (contd.)

 7.6 Sludge Data
         Estimate information on sludges generated by the end-of-pipe system.  Please attach an analysis of your sludge, il
         available.

         Annual   i Percent        Cost of            Cost of      i Cost of Disposal        Other
          Qty.     j  Solids     Transportation     Stabilization    ! (indicate S/unit)        Costs
          (Ibs.)    I           (indicate S/unit)    (indicate S/unit)                      (indicate $/unit)





                  nimiKHMi!^^

                                              Is sludge disposed of or recycled

                    Estimate the total cost associated with sludge disposal/recycle:                    $/yr

         I   Name of disposal/recycle site:
         i  ._._			 _
|             Location (city, state) of site:                                                              $,

         I                          Approximate distance to disposal/recycle site:                  miles
          illlPllPifflWWilW^^



 7.7 Permit Exceedance
         Has a failure, malfunction or other event associated with the end-of-pipe system resulted in a permit
         exceedance?
                                       yes1,   b            no    L
                                            TFWtt               '"WUfe


         If yes, please provide additional details.








                      WWIMHM^^


 7.8 Air Scrubber
         Is a wet air scrubber or other air pollution device in operation at your facility'?

                                                              no pi
                                                                 '-wm

         If yes, list the processes or chemicals (e.g., etching, formaldehyde) that prompted the purchase of the scnibber:




                                                                             MiBIIHiiMIHM^^
                                                          A-15

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-------
                        Section 8.0. Identification of Problems and Needs

8.4 Media
        I low would you prefer the results of this survey be presented (check all that apply).

                                                                       Printed report

                              On-line system accessible with personal computer and modem

                                                   Chi-disk system for personal computer

                                                        CD-ROM for personal computer

                                                              Workshop or conference

        | Other:
        ' *jwmWiiMiiiSi^^

8.5 Comments
        Please comment on any aspects of pollution prevention not covered by this survey.
8.6 Hours
        1'Inter the hours spent gathering data for and filling out this survey.
                                                       A-17

-------
Respondent
ID
42692
42692
42602
42692
42692
32842
32842
32842
42751
42751
42751
37817
! 37817
37817
37817
Tl
Tl
Tl
13
T3
33089
955703
36930A
273701
36930
36930
358000
41739
41739
44486
44486
107300
107300
107300
T2
T2
T2
T2
Process
electroless Ca
electroless Cu
dectroless Cu
electroless Cu
electooless Ctt
electroless Cu
electroless Cu
electroless Cu
electroiessCu
electroless Cu
electiolessCu
electroless Cu
etectroless Cu
electroless Cu
electtoless Cu
electroless Cu
electmJess Cu
electroless Cu
electroless Cu
electroless Cu
electfloless Co
electroless Cu
electroless Cu
electroless Cu
1 eteciroless Ca
electroless Cu
electroless Cu
electroless Cu
eteoroless C
electroless Cu
electroless Cu
electroless Cu
eteciroless Ca
electroless Cu
electroless Cu
electroless Cu
electroless Ca
electroless Cu
Product or Chemical
ca*aposii44
cuposit251A
$WPO$& 25IR
cuposit Z
9204 hole 580gai
13,365 gal
72<$Q ^i
80 gal
200 gal
12 gal
800 lb$
7,200 Ibs
7,700 gal
2,860 gal
1,500 gal
1,500 gal
1,000 Ibs
12 drums
300 gal
4,800 gal
4,510 gal
3,620 gal
2,800 gal
5,280 gal
5,280 gal
3,850 gal
2,3*0 gal
16,500 gal
16,500 gal
16,500 gal
60 gal
7,100 gal
700 gal
1,900 gal
Manufacturer
Shipley
Shipley
Shipley
Shipley
MacdermkJ
Shipley
Shipley
Shipley
Gewie
Shipley
Shipley
Crosslink
Crosslink
Crosslink
Crosslink
Shipley
Shipley
Shipley
Electrochemicals
Electrochemicals
EJectrochenticals
-
Shipley
Electrochemicals
Macdermid
Macdermid
Shipley
Electrochemicals
Electrochemicals
Macdermid
Macdetrnid
Macdomid
Macdermid
Macdermid
Shipley
Shipley
Shipley
Shipley
Cost
31643 $/gal
10.803 $/gal
15,912 $/gal
4.836 $/gal
33,644 $/gal
20.84 $/gal
10,95 $/gal
376.56 $/gal
-
-
-
25 $/gal
10,5 $/gal
650 $/gal
4.5 $/lb
0.99 $/lb
H,9$/gal
8.66 $/gal
12,86 $/gal
12.35 $/gal
4.8$/gal
68.99 $/drum
15,69 $/gal
12.5 $/gal
10.19 $/gal
8.11$/gal
15,21 $/gai
10.65 $/gal
10.81 $/gai
10.98 $/gal
8,87 S/gal
.
.
.
316$/gal
12.25 $/gal
3X76 $/gal
14.31 $/gal
B-2

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                   Appendix B
               Process Chemical  Data
Primary Process Chemicals Used by Survey Respondents
             Organized by Process Type
Respondent
ID
955703
42751
502100
502100
T3

44657
44657
44657
33089
33089
29710
955099
44486
43694
43841
T2
31838
133000
237900
279
279
279
3470
462800
955703
36930
36930
36930
44486
273701
502100
T3
36930

133000
237900
42692
Process
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate

Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
Cu electroplate
desmear
desmear
desmear
desmear
desmear
develop
developer
developer
developer

developer
developer
electroless Cu
Product or
Chemical
LPVE cleaner
liquid Cu sulfate
Cu sulfate
brightener solution
30" phosphorized Cu
anodes
12446 M-Cu 20C
75222 M-treat emulsion
12447 M-Cu 20 A
sulfuric acid
Cu sulfate
Cu anodes
Cu anodes
enplate AJO485
acidCuMHY
Cu nuggets
Cu nuggets
Cu brightener
Cu balls
Cu anodes
Cu sulfate
sulfuric acid
sodium persulfate
PC 667
sodium persuliate
neutrauzer2lG
M-permanganate-L
TL-7527
M-treat bio
M-treat bio
potassium carbonate
potassium carbonate
ADC 40
liquid potassium
carbonate 47%
Resolue 21 1
.potassium carbonate
746W concentrate
Annual
Usage
48 drums
2,310 gal
100 Ibs
80 gal
20,000 Ibs

430 gal
HO gal
100 gal
8>QOO Ibs
1,500 Ibs
4,314 Ibs
45,000 Ibs
10.120 Ibs
400 gal
3,700 Ibs
56,000 Ibs
6,600 gal
30,000 Ibs
23,000 Ibs
250 gal
500 gal
1,400 Ibs
840 gal
26,000 Ibs
24 drums
345 gal
3,080 gal
765 gal
660 gal
5,000 gal
40 Ibs
2,000 gal
7,425 gal

6,600 gal
5,000 gal
480 gal
Manufacturer
Duratech
CP Chemicals
-
-
Florida Cirtech

Macdermid
Macderrnid
Macdermid
[
Electrochemicals
Chem Services
-
Eathone
Sel-Rex
Western Reserve
Oliver Sales
Shipley
-
Great Western
-
'
-
Elecirochemicals
-
:
Macdermid
Emhone
Macdermid
Macdermid
Electrochemicals
:
Florida Cirtech
Hawkins

Surface Tek
Gallade
Shipley
Cost
18.28 S/dmm
-
-
-
1.95 $/lb

21.38 $/gal
48J $/gat
48.1 $/gal
0.22 S/lb
0.5 $/lb
2,2 $Ab
1.6$/lb
2.09 $/lb
28 $/gal
1,82 $flb
1.74$/lb
26.% $/gal
2.04 $/lb
1.74$Ab
-
-
0.18 $/lb
22$/gal
0.84 $/lb
34.28 $/ton
129.64 $/gal
9.62 $/gal
31.08$/gal
33,55 $/gal
4.8 $/gal
-
6.85 $/gal
3,16 $/gal

3.29 $/gal
3$/gal
52.27 S/gal
                        B-l

-------
Respondent
ID
36930A
36930A
273701
36930
6710
6710
6710
358000

358000
41739
44486
107300
43694
43694
43841
T2
T2
31838
107300
133000
133000
237900
3023
279
279
3470
965874
42692
42751
42751
947745
Tl
T3
44657
29710
36930
36930
Process
etch
etch
etch
etch
etch
etch
etch
etch

etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
gold plate
gold plate
gold plate
gold plate
gold plate
gold plate
gold plate
gold plate
gold plate
gold plate
Product or Chemical
high speed accugard
poly etch W
hy
-------
Respondent
ID
T2
946587
946587
31838
237900
237900
55595
55595
55505
55595
3023
279
279
279
3470
3470
3470
3470
965874
965874
965E74
32482
32842
42751
42751
947745
947745
37817
502100
502100
502100
Tl
T3

44657
33089
29710

29710
955099
29710

Process
electroless Cu
electroless Cu
electroless Cu
electroless Cu
etectroless Cu
electroless Cu
electroless Cu
electroless Cu
etectrote Co
electroless Cu
electroless Cu
electroless Cu
etectroiess Co
electroless Cu
electroless Cu
electroless Cu
etectroless Co
electroless Cu
electroless Cu
electroless Cu
etectroless Cu
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch
etch

etch
etch
etch

etch
etch
etch

Product or
Chemical
Orcupo$it 3350C
748 microetch
catapostt 44
Circuposit 3350A
335QA component
3350C component
CusttWite
sodium hydroxide
hydaogenperoxieJe
formaldehyde
85A
HN 502 nl cleaner cond
HN 503 Moe carrier
HN 505 Accelerator
Circuposit 3350 A
Circuposit 3350 R
Ca*3pO$it 44
etch 748
850A
850 R
Cobra Eleh
hydrogen peroxide
536R
etch replenisher
74$ etch
hunt accugard
ammonia hydroxide
ammoniacal etchant
sottiumpersulfate
cupric chloride
sodium chlorate
ultra etch 50 1499
ultra etch 20

ammonia etch
hydrogen peroxide
ammonium
chloride/hydroxide
cobra etch
ultra etch 50
ammonium
chloride/hydroxide
Annual
Usage
3,000 gal
45,500 Ibs
164 gal
18,480 gal
6,500 gal
3,300 gal
636,000 Ibs
298,214 gal
106389 gal
100,4 12 gal
14355 gal
150 Ibs
1,000 gal
3,000 Ibs
50,00011)
16,800 Ibs
75 gal
10,600 Ibs
2365 gal
1,265 gal
354 gal
34,500 Ib
900 gal
48,455 gal
827 Ifrs
3,300 gal
330 gal
12,540 gal
1,000 fcg
l,5001b
500 Ib
63 ,836 gal
8,000 gal

6,300 gal
4,000 Ibs
10,340 gal

3,808 Ib
72,000 gal
10*340 gal

Manufacturer
Shipley
Shipley
Shipley
Shipley
Shipley
Shipley
CP Chemical
Khamer Chemical
FMC
VW&R
Macdermid
Straus
Straus
Straus
Shipley
Shipley
Shipley
Shipley
Macdetmid
Macdermid
ElectrochemicaJs
Generic
Shipley
Phibro Tech
Shipley
Hunt
H
Old Bridge Chemicals
; *
-
+>
Macdermid
SouUwm Calif
Chemical
HubbardHall
Circuit Research
Macdermid

Electrochemicals
Macdermid
MacdermM

Cost
8.89$/gai
1.64$/lb
316,13 $/gal
11.04$/gal
11,93 S/gal
8.66 $/gal
0^$/lb
1.18 $/gal
1.68$/gaJ
1.23 $/gal
lOVgal
0.19 $/ssf
0,19$/ssf
0.19 $/ssf
1,55 $Ab
1.81 $/lb
4005/gaI
1.72$/lb
8S/gal
12 $/gal
23$/gal
0.365 $/lb
m03$&al
-
-
3.27 $/gal
U5$&al
1.75$/gal
*
-
H-
0.84$/gal
3>2$/gal

2.43 $/gal
13.25 $/gal
2.05 $/gal

2,29 $Ab
l$/gal
2,05$/gal

B-3

-------
Respondent
ID
965874
462800
462800
462800
946587
43841
43694
947745
37817
37817
Tl
Tl
44657
955703
29710
36930
36930
36930
6710
6710
358000
44486
44486
43841
946587
31838
3I83S
237900
462800
37817
37&17
T3
44657
955703
955703
42751
Process
HASL
HASL
HASL
HASL
material
microetch
nickel plate
other
other
other
other
other
other
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
oxide
resist
resist
resist
resist
resist strip
resist strip
resist strip
Product or
Chemical
flux 756 S
flux
flux
flux
Cu laminate
sodium persulfate
nickel sulfamate
OS 108 cleaner
isopropyl alcohol
854 spray/wipe
| sunfcrite44
ronaclean PC-454 1864
i Pa 129 screen eteansr
NPR502
MacubondSBW
omnibond plus 6220
omnibond plus 272
omnibond plus 271
NFR502
501A
sodium chlorite
omnibond plus 6220
omnibond plus 271
NPR502
pro bond oxide converter
oxide converter
probondSOA
DMAB
sodium chlorate
Glihole R
AS71BA
dry film photoresist
ristoiL
resist strip 4042
dttra$feiptLS42Q
PC 4055
Annual
Usage
607 gal
1,320 gal
440 gal
330 gal
568,000 sheets
13,000 Ib
200 gal
440 gal
550 gal
75 gal
3,080 gal
1,100 gal
275 gal
12 drums
455 gl
2,915 gal
1375 gal
1,949 gal
90 gal
220 gal
660 gal
1,650 gal
1,210 gal
255 gal
1,590 gat
2,400 gal
4,000 gal
350 gal
150,000 Ifcs
126 gal
120 gal
400,000 sq ft
170 rolls
72 drums
84 drums
5,335 gal
Manufacturer
Alpha Metals
Hygrade
Hygrade
Alpha Metals
various
FMC
Technics
Oliver Sales
i Amerex
ICC Chemicals
Atert Sales South
Learonal
f>CI
-
Macdermid
Macdermid
Macdermid
Macdermid
Electrochemicals
Electrochemicals
Dexter
Macdermid
Macdermid
Electrochemicals
Shipley
Shipley
Shipley
Shipley
-
Shi Koku Chemicals
Cutech
Dupont
Dpon$
-
Duratech
Ardrox
Cost
14 tfgal
11.75$/gal
11 $/gal
14.38 $/gal
7 $/sheet
1 $/lb
16$/gal
13.64 $/gal
2.95 $/gal
32.5 $/gal
3.2 $/gal
9.26 $/gal
16.75 $/gal
534 $/drum
2L959 $/gal
26.72 $/gal
20.87 $/gal
11.19$/gal
179,7 $/gal
23.48 $/gal
21,5 $/gal
29.67 $/gal
12.43 $/gal
115 $/gal
H9.6$/gal
138 $/gal
6.96 $/gal
1 16.53 $/gal
0.45 $/lb
38 $/gal
12.5 $/gal
0.38$/sqft
255.15 $/roIl
6.71 $/dmm
4.75 $/drum
-
B-6

-------
Respondent
ID
6710
358000
368000
41739
44486
43694
43841
T2
237900
3470
1 965874
32842
42692
947745
947745
37817
T3

T3
955703
955703
I 955099
36930A

273701
273701
J07300
107300
43841
946587
946587
31838
237900
55595
55595
3023
3470
3470
965874
Process
gold plate
gold plate
gold pla*e
gold plate
goldpiate
gold plate
gold plate
gold plate
goldpiate
gold plate
goldpiate
gold plate
HASL
HASL
HASL
HASL
HASL

HASL
HASL
HASL
HASL
HASL

HASL
HASL
HASL
HAS1
HASL
HASL
HASL
HASL
HASL
HASL
HASL
HASL
HASL
HASL
HASL
Product or
Chemical
gold
potassium gold cyanide
potassium gold cyanide
potassium gold cyanide
E-74 gold salts
potassium gold cyanide
potassium gold cyanide
potassium gold cyanide
potassium gold cyanide
potassium dicyanoaurate
potassium gold cyanide
potassium gold cyanide
AFI802
OS 611 flux
OS 622 fluid
flux
30"6Q#Otin4ead
plating
ref low/fusing oil
flux 891V
isopropyl alcohol
solder
HO 50 oil

l$lfowoilHO-lO
HOF-1 reflow flux
HASL flax
micro-etch
sofcJerbars
AF 1826 flux
solder
solder
twleatl solder
tun lead solder
flx
electrolytic solder
CE2203
flux
808
Annual
Usage
602
200 oz
6002
108 troy oz
96012
150 troy oz
8102
1,440 oz
340t
375 oz
23 troy 02
25 oz
5,960 g
180 gal
500 gal
1,100 gal
10,000 Ibs

400 gal
24 drums
48 drums
29,000 Ib
210 gal

1,200 gal
500 gal
7,920 gal
5,940 gal
2,50Qllb
4,675 gal
30,500 &s
7,900 Ibs
13,00011)8
34,850 Ibs
4,185 gal
125,250 Ib
21,600 Ibs
6,000 Ibs
495 sal
Manufacturer
Technics
Sel Rex
Engelhard
Technics
Engelhard
Technics
Technics
Sel Rex
EflgelhaflJ
Degussa
Technics
Technics
Dexter
Oliver Sales
Oliver Sales
Cutech
Florida Oftech

Florida Cirtech
-
occ
Dexter
Circuit Research
Corp
Circuit Research Co
Circuit Research Co
Pratta
Pratta
-
Dexter
Federated Fry
Kester
Alpha Metals
Alcomet
Alpha Metals
Dexter
Dexter
Dexter
Alpha Metals
Cost
433 $/os$ !
650$/oz
650$/oz
418.84 $/troyoz
435 $/02 !
450$/troyoz
442$/oz
_
425$/02
420$/oz
423$troyo2
429.32 $/oz
10,25 $/gal
11.83$/gal
15.67 $/gal
11.49$/gal
2.5 $/lb

17$/gal
31.74 $/drum
3.47$/drum
2.5$flb
20.02 $/gal

i *7$/gal
17$/gal
-.
_
2.6^$Ab
19.8$/gal
2.35 $/lb
2.82 $/lb
2,59 $Ab
2.5$/lb
12.95 $/gal
2.18$/lb
0,72 $/lb
2.04 $/lb
0.23 Steal
B-5

-------
Respondent
ID
43841
237900

965874
462800
43841
43694
33089
29710
29710
358000
107300
T2
946587
947745
947745
502100

33089

6710

502100

502100

502100

42692
42692
42751
42751
42751
947745
947745
37817
37817
37817
Tl
Tl
T3
955703
29710
29710
Process
solder strip
solder strip

solder strip
solder strip
soldermask
tin lead plate
tin lead strip
tin lead strip
tin lead strip
tin lead strip
tin lead strip
tin lead strip
tin lead strip
tin lead strip
tin lead strip
tin lead
electroplate
tin lead
electroplate
tin lead
electroplate
tin lead
electroplate
tin lead
electroplate
tin-lead
electroplate
nr
various
various
various
various
various
various
various
various
various
various
various
various
various
various
various
Product or
Chemical
PC 606
1125Ardrox/2810
Dexter
9107
Cubrite cleaner
ccaiforinask
solderon PC
nitric acid
eliminator 2
enplate AD-485
nitric acid/ferric nitrate
tin stripper
solder stripper
SS 2803
OS 201 stripper
OS 203 stripper
tin mac cleaner

ftuoborie acid

fluoboric acid

tartan brightener

staneous sulfate

leadfluoborate

RS 1609
sutfuric acid
hydrochloric acid
caustic soda 50%
caustic soda 25%
sulfuric acid
fluoboric acid
sulfuric acid
sodium hydroxide
muriatic acid
sutfuric acid 1060
hydrochloric acid 4968
ML371
310 microetch
sulfuric acid
hydrochloric acid
Annual
Usage
330 gat
5,600 gal

2,050 gal
330 gal
123,034 sq ft
400 gal
1,200 Ibs
1,155 gal
5,820 Ib
1,800 gal
41,250 gal
9,000 gal
7,315 gal
120 gal
120 gal
20 gal

6,000 &s

1,650 gal

180 Ib

150 gal

100 gal

4,620 g
108,000 Ib
2,475 gal
1320 gal
16,665 gal
660 gal
150 gal
550 gal
495 gal
550 gal
51,0001b
440 gal
1,500 gal
19,800 Ibs
100,440 Ib
86,205 Ib
Manufacturer
EJectrcx^hemicais
Ardrox/Dexter

Macdexmid
Toryon Tech
Dynachem
Learonal
Electrochemieals
Macdermid
Enmone
Dexter
Dexter
Oliver Sales
Shipley
Oliver Sales
Oliver $ales
r

Btecttochetwcais

Van Waters

-

-

-

Dexter
Generic
Generic
Genetic
Generic
-
-
Araeiex
Amerex
Amerex
Photo Chemical
Apper son Chemical
Enthone/OMI
Duratech
Chem Services
Chem Services
Cost
25$/gal
5$/gal

10 $/gal
13.6 $/gal
0.85$/sqft
35 $/gal
0.15 $/lb
10.89 $/gal
1.77 $/lb
10 SAiter
-
8.5 $/gal
i.638 $/lb
6.75 $/gal
10.5 $/gal
-

1,01 $feal

1.47$/gal

-

-

-

7.5 $/gal
0.3128 $/lb
-
-
-
I.S5 $/gaI
20 $/gal
1.49 $/gal
1.84$/gal
l.I$/gai
0.24 $/lb
6$/gal
24.44 $/gal
1.85 $flb
0.25 $/lb
0.5 $Ab
B-8

-------
Respondent
ID
947745
502100
T3
273701
36930
6710
41739
44486
107300
43694
946587
31838
133000
237900
3023
3023
965874
358000
965874
41739

T3
T3
41739

107300
946587
946587
55595
279
279
3470
3470
3470
41739
955099
955099
273701
41739
44486
43841
Process
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist Strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
resist strip
solder mask
solder mask

solder mask
solder mask
solder mask

solder mask
solder mask
solder mask
solder mask
solder mask
solder mask
solder mask
solder mask
solder mask
solder mask
solder strip
solder strip
solder strip
solder strip
solder strip
solder strip
Product or
Chemical
OS 901
sodium hydroxide
OS 900 stripper
alkastrip 821
RS-1609
SQI
PC4055
alkastrip
resist stripper
PC 4055
RS 1675
resist stripper
RS 1607 strip
4077 Ardrox MEA
Ardrox 4099
RS 1606
Delta strip 1675
monoethanolamine
screening ink
SR- 1000 CRN solder
mask
taiyo PSR 4000
dexter hy sol SRI 000
epic 200 GRN solder
mask
PSR 4000
probimer 52
probimer DW 91
PPR-102A ink
solder mask SR 1020
screen cleaner
SR 8100
SR 1000
SD 2461
914 screen emulsion
1115
techni solder NF'
super one step
PC 11 25 stripper
solstrip 150
Zass A-f-B one step
Annual
Usage
120 gal
800 lb
1,400 gal
420 gal
3, 190 gal
1,100 gal
3,300 gal
2,970 gal
22,000 gal
5,000 gal
9,405 gal
7,260 gal
6,000 gal
8,000 gal
3,960 gal
18,8 10 gal
990 gal
2,000 gal
578 gal
432 gal

750kg
200 gal
360kg

20,000 kg
14,175 kg
8,280 kg
879 gal
300 gal
300 gal
1,344kg
4,000 Ibs
550 kg
192 gal
7,600 gal
780 gal
2,800 gal
2,400 gal
5,940 gal
2,400 gal
Manufacturer
Oliver Sales
.
Florida Cirtech
Dynachem-Morton
Dexter
Morton
Alphametal
Morton
Dexter
Alphametal
Dexter
AMP-AK20
Dexter
Ardrox
Alpha Ardrox
Dexter
Hisco
Atotech
Dexter Hysol
Dexter Hy Sol

Taiyo America
Dexter Hysol
Dynachem

Taiyo
Ciba Gtegy Probimer
Ciba Geigy Probimer
Amp PfcUco
Dexter
Florida Cirtech
Dexter
Dexter
Lacke Werke Peters
Sericol
Aleha Metals
Technics
Electrochemicals
Alphametal
Electrochemicals
Electrochemicals
Cost
14,05 $/gal
_
9,68$/gal
25 $/gal
9$/gal
9.75 $/gal
10.69 $/gal
ll$/gal
*
11.5$/gal
8,75 $/gal
7.25 $/gal
8,09 $/gal
15.2 $/gal
7,6$/gal
8$/gal
10 $/gal
5.63 $/liter
75$/gal
76 $/gal

70$/kg
74.7 $/gal
128 $/kg

_
56,7 $/kg
32.5 $/kg
32,5 $/gal
94.5 $/gal
ll$/gal
36.5 $/kg
8,6 S/lb
58$/kg
37,92 $/gai
8$/gal
20$/gal
8.5 $/gal
5,15$/gal
7.92 $/gal
15 Steal
B-7

-------
Respondent
ID
43694
43841
43841
T2
946537
31838
31838
31838
3183$
133000
237900

55595
3023
Process
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment
waste treatment

waste treatment
waste treatment
Product or
Chemical
caustic soda 50%
Floe 402
EMR-2
EMR reducing agent
reduced iron powutois
Dubois
Great Westen* MRAP
Morton Thiokol
Morton ThiokoJ
generic
generic
-
Southern Waste
Treatment
Venmet
EFKme
Cost
.
50$/gal
US/gai
18.5 $/gal
K8$/lb
22$/gal
13,23 $&ai
0.97 $/lb
0^$/lb
0.39 $/lb
8.59$/gal

29$/gal
0.62 $/sal
     *& U.S. GOVERNMENT PRINTING OFFICE: 1995 615-003/21022
B-10

-------