<PAGE>   1
                                                                    Exhibit 4.21

                             THE CERPLEX GROUP, INC.



                         WAIVER AND AMENDMENT AGREEMENT


                             DATED DECEMBER 9, 1996




                                   $17,250,000
            SERIES A SENIOR SUBORDINATED NOTES DUE NOVEMBER 19, 2001
<PAGE>   2
                         WAIVER AND AMENDMENT AGREEMENT


         WAIVER AND AMENDMENT AGREEMENT (this "Agreement"), dated December 9,
1996, by and among THE CERPLEX GROUP, INC., a Delaware corporation (together
with its successors and assigns, the "Company"), THE NORTHWESTERN MUTUAL LIFE
INSURANCE COMPANY, JOHN HANCOCK MUTUAL LIFE INSURANCE COMPANY and NORTH ATLANTIC
SMALLER COMPANIES INVESTMENT TRUST PLC (collectively, the "Noteholders").

                                    RECITALS:

         A. The Company has entered into those certain separate Note Purchase
Agreements, each dated as of November 19, 1993 (collectively, as amended
pursuant to the terms of each of the amendment agreements set forth in Schedule
A to this Agreement and as in effect prior to the effectiveness of this
Agreement, the "Existing Note Purchase Agreement," and, as amended by this
Agreement, the "Amended Note Purchase Agreement"), with each of the Noteholders,
pursuant to which the Company originally issued and sold to the Noteholders

                  (i) an aggregate principal amount of Seventeen Million Two
         Hundred Fifty Thousand Dollars ($17,250,000) of the Company's Series A
         9.00% Senior Subordinated Notes Due November 19, 2001 (as amended, the
         "Notes"), and

                  (ii) an aggregate principal amount of Five Million Seven
         Hundred Fifty Thousand Dollars ($5,750,000) of the Company's Series B
         9.00% Senior Subordinated Notes Due November 19, 2001 (the "Series B
         Notes"). The Company has prepaid the Series B Notes and such Series B
         Notes are no longer issued and outstanding.

         B. The Noteholders are the current holders of one hundred percent
(100%) of the Notes outstanding as of the Effective Date.

         C. Pursuant to a notice to the Noteholders dated September 23, 1996,
the Company notified the Noteholders of certain Defaults and Events of Defaults
under Section 6.3 and Section 6.4 of the Existing Note Purchase Agreement (the


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"Noticed Events of Default," such term to include, for purposes of avoidance of
doubt, all Defaults and Events of Defaults under Section 6.3 and Section 6.4 of
the Existing Note Purchase Agreement that may have existed prior to the date of
such notice or after the date of such notice and prior to the effective date of
the October 1996 Waiver (as hereinafter defined)) and the Company has requested
that the Noteholders continue the waiver of such Noticed Events of Default
provided for in the October 1996 Waiver until March 31, 1997.

         D. Pursuant to a Waiver and Amendment Agreement dated as of October 31,
1996, the Noteholders waived the aforesaid Noticed Events of Default until
November 30, 1996 and, pursuant to a letter agreement dated November 26, 1996,
extended such waiver until December 9, 1996 (the "October 1996 Waiver").

         E. The Company has further requested that certain of the provisions in
the Existing Note Purchase Agreement be amended, as more particularly provided
herein.

         F. The Noteholders are agreeable, subject to the terms and conditions
set forth below, to granting the aforesaid waivers and modifying the Existing
Note Purchase Agreement as hereinafter set forth, and in connection therewith,
each of the Company and the Noteholders has agreed to amend the Existing Note
Purchase Agreement as set forth herein.

                                   AGREEMENT:

         NOW THEREFORE, for valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree as follows:

         SECTION 1.        DEFINED TERMS.

         The terms used herein and not defined herein shall have the meanings
assigned to such terms in the Existing Note Purchase Agreement. As used in this
Agreement, the following terms have the respective meanings specified below:

         "AGREEMENT, THIS" -- means this Waiver and Amendment Agreement, as it
may be amended from time to time.

         "AMENDED NOTE PURCHASE AGREEMENT" -- Recital A.

         "COMPANY" -- the introductory sentence.


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<PAGE>   4
         "EFFECTIVE DATE" -- Section 5.

         "EXISTING NOTE PURCHASE AGREEMENT" -- Recital A.

         "1996 WARRANT AGREEMENT" -- Section 3.2.

         "NOTEHOLDERS" -- the introductory sentence.

         "NOTES" -- Recital A.

         "NOTICED EVENTS OF DEFAULT" -- Recital C.

         "OCTOBER 1996 WAIVER" -- Recital D.

         SECTION 2.        WAIVER.

         Subject to the satisfaction of the conditions set forth in Section 4,
the Noteholders hereby continue the waiver provided in the October 1996 Waiver
in respect of each of the Noticed Events of Default until March 31, 1997 and
agree that the effectiveness of Section 6.3 and Section 6.4 shall be temporarily
suspended from and including the effective date of the October 1996 Waiver to
and including the earlier to occur of (a) the date that any holder of Senior
Debt takes any action in respect of any default or any event of default under
any Senior Credit Document and (b) March 31, 1997 (the "Reinstatement Date").
After the Reinstatement Date, Section 6.3 and Section 6.4 shall be in full force
and effect. Except for the foregoing express waivers and suspensions, the terms
of this Agreement shall not operate as a waiver of, or otherwise prejudice, the
rights, remedies or powers of the Noteholders under the Note Purchase Agreement,
under the Notes or under applicable law and all of such rights, remedies and
powers are hereby expressly reserved.

         SECTION 3.        AMENDMENTS TO THE EXISTING NOTE PURCHASE AGREEMENT;
1996 WARRANT AGREEMENT; AFFIRMATION.

         3.1      AMENDMENTS TO THE EXISTING NOTE PURCHASE AGREEMENT.

         The Company and, subject to the satisfaction of the conditions set
forth in Section 5, each of the Noteholders hereby consent and agree to the
amendments to the Existing Note Purchase Agreement set forth in Exhibit A to
this Agreement. Each such amendment is incorporated herein by reference as if
set forth verbatim in this Agreement.


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<PAGE>   5
         3.2      AMENDMENT TO THE EXISTING 1996 WARRANT AGREEMENT.

         In connection with the October 1996 Waiver, that certain Warrant
Agreement (the "1996 Warrant Agreement"), dated as of April 15, 1996, among the
Company and the Noteholders was changed by amending and restating the definition
of "Initial Purchase Price" therein to mean $2.50. For purposes of the avoidance
of doubt and in confirmation of said amendment, each of the Warrant Certificates
(as such term is defined in the 1996 Warrant Agreement) issued under the 1996
Warrant Agreement and currently outstanding as well as Exhibit A to the 1996
Warrant Agreement are hereby further amended and modified by changing the
references therein to "initial purchase price" and "Purchase Price" from "Six
Dollars ($6.00) per share" to "Two Dollars and Fifty Cents ($2.50) per share."
This amendment to each of the Warrant Certificates currently outstanding shall
be effective without any further action required on the part of the Noteholders
or the Company and without the need to submit such Certificates to Company for
any notation of said change thereon or to otherwise exchange such Certificates
for new Warrant Certificates.

         3.3      AFFIRMATION OF OBLIGATIONS.

         The Company hereby acknowledges and affirms all of its obligations
under the terms of the Existing Note Purchase Agreement, as amended hereby, and
the 1996 Warrant Agreement and the Warrant Certificates issued thereunder, as
amended hereby.

         SECTION 4.        WARRANTIES AND REPRESENTATIONS.

         To induce the Noteholders to enter into this Agreement, the Company
warrants and represents to the Noteholders that as of the Effective Date:

         4.1      CORPORATE ORGANIZATION AND AUTHORITY.

         The Company:

                  (a) is a corporation duly incorporated, validly existing and
         in good standing under the laws of the State of Delaware;

                  (b) has all legal and corporate power and authority to own and
         operate its Properties and to carry on its 


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<PAGE>   6
         business as now conducted and as presently proposed to be conducted;

                  (c) has all licenses, certificates, permits, franchises and
         other governmental authorizations necessary to own and operate its
         Properties and to carry on its business as now conducted and as
         presently proposed to be conducted, except where the failure to have
         such licenses, certificates and permits, either individually or in the
         aggregate, would not have, and could not reasonably be expected to
         have, a Material Adverse Effect; and

                  (d) has duly qualified or has been duly licensed, and is
         authorized to do business and is in good standing, as a foreign
         corporation in each state except where the failure to be so qualified
         or licensed and authorized and in good standing, either individually or
         in the aggregate, would not have, and could not reasonably be expected
         to have, a Material Adverse Effect.

         4.2      COMPLIANCE WITH LAW.

         The Company:

                  (a) is not in violation of any law, ordinance, governmental
         rule or regulation to which it is subject; and

                  (b) has not failed to obtain any license, certificate, permit,
         franchise or other governmental authorization necessary to the
         ownership of its Property or to the conduct of its business;

which violation or failure to obtain, either individually or in the aggregate,
would have, or could reasonably be expected to have, a Material Adverse Effect.

         4.3      LEGAL AND AUTHORIZED; OBLIGATIONS ARE ENFORCEABLE.

                  (a) AUTHORIZATION. The execution and delivery by the Company
         of this Agreement and the performance by the Company of its obligations
         hereunder and under the Amended Note Purchase Agreement are within the
         corporate powers of the Company and do not conflict with, result in any
         breach in any of the provisions of, constitute a default under, or
         result in the creation of any Lien upon any Property of the Company
         under the provisions of, any agreement, charter instrument, bylaw 


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<PAGE>   7
         or other instrument to which it is a party or by which it or any of its
         Property may be bound.

                  (b) OBLIGATIONS ARE LEGAL AND ENFORCEABLE. The execution and
         delivery by the Company of this Agreement have been duly authorized by
         all necessary action on the part of the Company, and this Agreement has
         been executed and delivered by one or more duly authorized officers of
         the Company. This Agreement and the Amended Note Purchase Agreement
         constitute legal, valid and binding obligations of the Company,
         enforceable against the Company in accordance with their respective
         terms, except that the enforceability thereof may be:

                           (i) limited by applicable bankruptcy, reorganization,
                  arrangement, insolvency, moratorium or other similar laws
                  affecting the enforceability of creditors' rights generally;

                           (ii) subject to the availability of equitable
                  remedies; and

                           (iii) with respect to indemnity and contribution,
                  limited by state or federal laws relating to Securities or by
                  the public policy underlying such laws.

         4.4      PENDING LITIGATION.

         Except as set forth in Schedule 4.4, there are no proceedings, actions
or investigations pending or, to the knowledge of the Company, threatened
against or affecting the Company in any court or before any Governmental
Authority or arbitration board or tribunal that, either individually or in the
aggregate, would have or could reasonably be expected to have a Material Adverse
Effect. The Company is not in default with respect to any judgment, order, writ,
injunction or decree of any court, Governmental Authority or arbitration board
or tribunal that, either individually or in the aggregate, would have or could
reasonably be expected to have a Material Adverse Effect.

         Except as previously disclosed to the Noteholders, the Company has not
received any notice of termination of any material contract, lease or other
agreement or suffered any material damage, destruction or loss (whether or not
covered by insurance) or had any employee strike, work-stoppage, slowdown or
lock-out or any substantial, non-frivolous threat 


                                       6
<PAGE>   8
directed to it of any imminent strike, work-stoppage, slowdown or lock-out.

         4.5      GOVERNMENTAL CONSENT.

         Neither the nature of the Company, nor of any of its businesses or
Properties, nor any relationship between the Company and any other Person, nor
any circumstance in connection herewith or in connection with the execution and
delivery of this Agreement is such as to require a consent, approval or
authorization of, or filing, registration or qualification with, any
Governmental Authority on the part of the Company as a condition to the
execution and delivery thereof.

         4.6      NO DEFAULTS.

                  (a) NO OTHER DEFAULTS. No Defaults or Events of Default exist,
         other than the Noticed Events of Default.

                  (b) FINANCING DOCUMENTS. No event has occurred and no
         condition exists that, upon the execution, delivery and effectiveness
         of this Agreement would constitute a Default or an Event of Default.

                  (c) CHARTER INSTRUMENT, OTHER AGREEMENTS. The Company is not
         in violation in any respect of any term of any charter instrument or
         bylaw. Except as set forth in Schedule 4.6, the Company is not in
         violation in any material respect of any term in any agreement or other
         instrument to which it is a party or by which it or any of its Property
         may be bound, which would have, or could reasonably be expected to
         have, a Material Adverse Effect.

         SECTION 5.        CONDITIONS.

         The waiver by the Noteholders set forth in Section 2 and the consent of
the Noteholders to the amendments described in Section 3 shall become effective
on December 9, 1996 (the "Effective Date") if all of the following conditions
have on or prior to such date been satisfied:

         5.1      EXECUTION AND DELIVERY OF THIS AGREEMENT.

         The Company and the Required Holders shall have executed and delivered
counterparts of this Agreement.

         5.2      WAIVER BY HOLDERS OF SENIOR DEBT.


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<PAGE>   9
         The Company and each holder of Senior Debt whose consent is required
therefor pursuant to the terms of the Senior Credit Documents shall have
executed and delivered waivers and/or amendments with respect to all events of
default which exist under such Senior Credit Documents. The Company shall have
delivered to each Noteholder a copy of the Second Amendment to Credit Agreement
and Limited Waiver entered into among the Company and the holders of Senior
Debt, together with a certification by a Senior Officer of the Company stating
that such copy is a true and correct copy and such Second Amendment to Credit
Agreement and Limited Waiver cures or waives all events of default which exist
under the Senior Credit Documents as of the date hereof.

         5.3      NO DEFAULT; REPRESENTATIONS AND WARRANTIES TRUE.

         After giving effect to Section 2, hereof, no Default or Event of
Default under the Amended Note Purchase Agreement shall exist, the warranties
and representations set forth in Section 4 hereof shall be true and correct on
the Effective Date, and the Noteholders shall have received a certificate, dated
as of the Effective Date and signed by a Senior Officer, certifying to such
matters and certifying that all of the conditions specified in this Section 5
have been satisfied.

         5.4      AUTHORIZATION OF TRANSACTIONS.

         The Company shall have authorized, by all necessary corporate action,
its execution, delivery and performance of this Agreement and the consummation
of all transactions contemplated by this Agreement and evidence of the same
shall have been delivered to the Noteholders. The Noteholders shall have
received a certificate, dated as of the Effective Date and signed by the
Secretary or the Assistant Secretary of the Company, certifying to the
resolutions in respect of such authorization and to such other matters as the
Noteholders shall reasonably request.

         5.5      OPINIONS OF COUNSEL.

         The Noteholders shall have received from each of (a) Brobeck, Phleger &
Harrison, counsel to the Company, and (b) Hebb & Gitlin, a legal opinion
substantially in the form set forth in Exhibit B1 and Exhibit B2, respectively,
and as to such other matters as the Noteholders may reasonably request.

         5.6      EXPENSES.


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<PAGE>   10
         The Company shall have paid all costs and expenses to the Noteholders
relating to this Agreement in accordance with Section 6.6 (including, without
limitation, any attorney's fees and disbursements).

         5.7      PROCEEDINGS SATISFACTORY.

         All proceedings taken in connection with this Agreement shall be
satisfactory to the Noteholders and their special counsel. The Noteholders and
their special counsel shall have received copies of such documents and papers as
they may reasonably request in connection therewith, in form and substance
satisfactory to them.

         SECTION 6.        MISCELLANEOUS.

         6.1      GOVERNING LAW.

         THIS AGREEMENT SHALL BE CONSTRUED, INTERPRETED AND ENFORCED IN
ACCORDANCE WITH, AND GOVERNED BY, INTERNAL NEW YORK LAW.

         6.2      DUPLICATE ORIGINALS.

         Two or more duplicate originals of this Agreement may be signed by the
parties, each of which shall be an original but all of which together shall
constitute one and the same instrument. This Agreement may be executed in one or
more counterparts and shall be effective when at least one counterpart shall
have been executed by each party hereto, and each set of counterparts which,
collectively, show execution by each party hereto shall constitute one duplicate
original.

         6.3      EFFECT OF THIS AGREEMENT.

         Except as specifically provided in this Agreement, no terms or
provisions of the Existing Note Purchase Agreement have been modified or changed
by this Agreement and the terms and provisions of the Existing Note Purchase
Agreement, as amended hereby, shall continue in full force and effect. This
Agreement and the waivers and amendments contained herein shall have and be in
effect on and after the Effective Date.


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<PAGE>   11
         6.4      WAIVERS AND AMENDMENTS OF THIS AGREEMENT.

         Neither this Agreement nor any term hereof may be changed, waived,
discharged or terminated orally, or by any action or inaction, but only by an
instrument in writing signed by the party against which enforcement of the
change, waiver, discharge or termination is sought.

         6.5      SECTION HEADINGS.

         The titles of the sections hereof appear as a matter of convenience
only, do not constitute a part of this Agreement and shall not affect the
construction hereof.

         6.6      COSTS AND EXPENSES.

         On the Effective Date, the Company shall pay all costs and expenses of
the Noteholders related hereto, including, but not limited to, the statement for
fees and disbursements of the Noteholders' special counsel presented to the
Company on the Effective Date for matters in connection with this Agreement. The
Company will also pay upon receipt of any statement thereof, each additional
statement for fees and disbursements of the Noteholders' special counsel
rendered after the Effective Date in connection with this Agreement. The
obligations of the Company under this Section 6.6 shall survive the payment or
prepayment of the Notes and the termination of the Amended Note Purchase
Agreement.

         6.7      SURVIVAL.

         All warranties, representations, certifications and covenants made by
the Company hereunder or in any certificate or other instrument delivered
pursuant hereto or thereto shall be considered to have been relied upon by the
Noteholders and shall survive the execution of this Agreement, regardless of any
investigation made by or on behalf of the Noteholders. All statements in any
such certificate or other instrument shall constitute warranties and
representations of the Company hereunder.

         [REMAINDER OF PAGE INTENTIONALLY BLANK. NEXT PAGE IS SIGNATURE PAGE.]


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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed on their behalf by a duly authorized officer or agent thereof, as the
case may be, as of the date first above written.


                                          THE CERPLEX GROUP, INC.



                                          By
                                              --------------------------------
                                              Name:
                                              Title:



Accepted:

THE NORTHWESTERN MUTUAL LIFE INSURANCE COMPANY



By
  ---------------------------------------
  Name:
  Title:


JOHN HANCOCK MUTUAL LIFE INSURANCE COMPANY


By
  ---------------------------------------
  Name:
  Title:


NORTH ATLANTIC SMALLER COMPANIES INVESTMENT TRUST PLC


By
  ---------------------------------------
  Name:
  Title:
<PAGE>   13
[Signature page to the WAIVER AND AMENDMENT AGREEMENT among THE CERPLEX
GROUP, INC. and the Noteholders listed therein.]


                                      S-2
<PAGE>   14
                                                                      SCHEDULE A

Amendment No. 1 to Note Purchase Agreement dated as of May 26, 1994.

Amendment No. 2 to Note Purchase Agreement dated as of July 29, 1994.

Amendment Agreement dated as of October 27, 1994.

Waiver and Amendment Agreement dated as of April 15, 1996.

Waiver and Amendment Agreement dated as of October 31, 1996 (as extended by that
certain letter agreement dated November 26, 1996).


                                  Schedule A-1
<PAGE>   15
                                                                    SCHEDULE 4.4


                        PENDING AND THREATENED LITIGATION

                         [To be provided by the Company]


                                 Schedule 4.4-1
<PAGE>   16
                                                                    SCHEDULE 4.6


                    VIOLATIONS OF AGREEMENTS AND INSTRUMENTS

                         [To be provided by the Company]


                                 Schedule 4.6-1
<PAGE>   17
                                                                       EXHIBIT A


                 AMENDMENTS TO EXISTING NOTE PURCHASE AGREEMENT


         1. AMENDMENT TO SECTION 6 OF THE EXISTING NOTE PURCHASE AGREEMENT.
Section 6 of the Existing Note Purchase Agreement is hereby amended by adding
the following Section 6.18 and Section 6.19 immediately following Section 6.17
in the Existing Note Purchase Agreement:

                  "6.18 MINIMUM PROFITABILITY. The Company shall not permit
         Consolidated Net Income (as defined in the Wells Fargo Credit
         Agreement) for the fiscal quarter of the Company ending December 31,
         1996 to be less than ($7,000,000).


                  6.19 MINIMUM RATIO OF ACCOUNTS RECEIVABLE TO LOANS. The
         Company shall not permit the ratio of (i) the sum of (a) the aggregate
         amount of all Accounts Receivable (as defined in the Wells Fargo Credit
         Agreement) of the Company and the Subsidiaries as of the last day of
         any fiscal quarter of the Company and (b) the book value as defined by
         GAAP of all Inventory (as defined in the Wells Fargo Credit Agreement)
         of the Company and the Subsidiaries as of such day to (ii) the
         aggregate principal amount of all outstanding Wells Fargo Credit
         Agreement Debt as of such day to be less than 0.80:1.00."

         2.       AMENDMENT TO SECTION 7.1.

                  (a) Clause (j) of Section 7.1 of the Existing Note Purchase
         Agreement is hereby amended by deleting the word "and" at the end of
         such clause.

                  (b) Clause (k) of Section 7.1 of the Existing Note Purchase
         Agreement is hereby amended by deleting the period at the end of such
         clause and substituting "; and" in lieu thereof.

                  (c) Section 7.1 of the Existing Note Purchase Agreement is
         hereby by adding the following clause (l) immediately following clause
         (k) in Section 7.1 of the Existing Note Purchase Agreement:


                                  Exhibit A - 1
<PAGE>   18
                           "(l) MONTHLY FINANCIAL STATEMENTS -- as soon as
                  available and in any event prior to December 10, 1996 with
                  respect to the month ended October 31, 1996 and within 30 days
                  after the end of each month thereafter, commencing with the
                  month ended November 30, 1996, the consolidated balance sheet
                  of the Company and the Subsidiaries as at the end of such
                  month, the related consolidated statements of income,
                  stockholders' equity and cash flows of the Company and the
                  Subsidiaries for such month, and an income statement for such
                  month showing the results of operations for each division of
                  the Company and the Subsidiaries, all in reasonable detail and
                  certified by the chief financial officer of the Company that
                  they fairly present the financial condition of the Company and
                  the Subsidiaries as at the dates indicated and the results of
                  their operations and their cash flows for the periods
                  indicated, subject to changes resulting from audit and normal
                  year-end adjustments."

         3.       AMENDMENT TO SECTION 8.1(C).

         The following is hereby added to the end of Section 8.1(c) of the
Existing Note Purchase Agreement: "or Section 6.18 or Section 6.19."


                                  Exhibit A - 2
<PAGE>   19
                                                                      EXHIBIT B1

                    FORM OF OPINION OF COUNSEL TO THE COMPANY



                 [Letterhead of Brobeck, Phleger & Harrison LLP]


                                                        [Effective Date]


To Each of the Persons
Listed on Annex 1 Hereto

         Re:      The Cerplex Group, Inc.,
                  a Delaware corporation (the "Company")

Ladies and Gentlemen:

         Reference is made to the Waiver and Amendment Agreement dated December
9, 1996 (the "Amendment"), among the Company and each of the Persons listed
under Part A of Annex 1 hereto (the "Noteholders"), which waives and amends
certain of the provisions of, as specified in the Amendment, those certain Note
Purchase Agreements, each dated as of November 19, 1993, as amended
(collectively, as in effect immediately prior to the effectiveness of the
Amendment, the "Existing Note Purchase Agreement," and, as amended by the
Amendment, the "Amended Note Purchase Agreement"), between the Company and each
of the Persons listed on Annex 1 thereto, relating to, among other things, the
purchase and sale of the Company's Series A 9.00% Senior Subordinated Notes due
November 19, 2001 (the "Notes"). The capitalized terms used herein and not
defined herein have the meanings specified in the Amendment and the Amended Note
Purchase Agreement, as the case may be.

         We have acted as special counsel to the Company in connection with the
Amendment and the transactions contemplated thereby. This opinion is being
delivered to you in compliance with Section 5.5 of the Amendment.

         In connection with this opinion letter, we have examined originals, or
copies certified or otherwise identified to our satisfaction, of such documents,
corporate records, certificates, including certificates of public officials, and
other 


                                 Exhibit B1 -1
<PAGE>   20
instruments as we have deemed necessary or advisable for purposes of this
opinion, including those relating to the authorization, execution and delivery
of the Amendment. In addition, we have examined the following documents:

                  (a) an executed copy of the Existing Note Purchase Agreement;

                  (b) the Notes;

                  (c) an executed copy of the Amendment;

                  (d) an executed certificate of a Senior Officer of the
         Company, delivered pursuant to Section 5.3 of the Amendment;

                  (e) an executed certificate of the Secretary of the Company,
         delivered pursuant to Section 5.4 of the Amendment;

                  (f) the bylaws of the Company, the records of proceedings of
         the board of directors of the Company and a certified copy of the
         Restated Certificate of Incorporation of the Company, all as in effect
         on the date hereof;

                  (g) a long-form good standing certificate with respect to the
         Company from the Secretary of State of the State of Delaware and
         foreign good standing certificates with respect to the Company from
         each of the states set forth in Annex 2 hereto; and

                  (h) originals, or copies certified or otherwise identified to
         our satisfaction, of such other documents, records, instruments and
         certificates of public officials as we have deemed necessary or
         appropriate to enable us to render this opinion.

         We have assumed, with your consent, (i) the genuineness of all
signatures (other than signatures of officers of the Company), (ii) the
authenticity of all documents submitted to us as originals, and (iii) the
conformity to original documents of all documents submitted to us as certified,
conformed or photostatic copies. As to any facts material to the opinions
hereinafter expressed which we did not independently establish or verify, we
have relied, without investigation, upon 


                                  Exhibit B1 -2
<PAGE>   21
certificates, statements and representations of representatives of the Company;
and we have no actual knowledge of any material inaccuracies in any of the facts
contained therein. In making our examination of the documents executed by
Persons other than the Company, we have assumed that each such Person had the
power to enter into and perform all its obligations thereunder and the due
authorization of, and the due execution and delivery of, such documents by each
such Person, and that such documents have been duly authorized, executed and
delivered by, and are binding upon and enforceable against, such Person.

         As used in this opinion, the phrase "to the best of our knowledge"
means as to matters of fact that, based on the actual knowledge of individual
attorneys within the firm responsible for handling matters for the Company and
after an examination of documents referred to herein and after inquiries of
certain officers of the Company, we find no reason to believe that the opinions
expressed are factually incorrect; but beyond that we have made no factual
investigation for the purposes of rendering this opinion.

         This opinion relates solely to the laws of the States of California and
New York, the General Corporation Law of the State of Delaware and applicable
Federal laws of the United States, and we express no opinion with respect to the
effect or applicability of the laws of other jurisdictions.

         Based on the foregoing, we are of the opinion that:

         1. The Company is a corporation duly incorporated, validly existing and
in good standing under the laws of the State of Delaware and has all requisite
corporate power and authority to carry on its business and own its Property.

         2. The Company has duly qualified and is in good standing as a foreign
corporation in each jurisdiction where the character of its Properties or the
nature of its activities makes such qualification necessary, except where the
failure to so qualify and be in good standing would not have a material adverse
effect on the Company or affect the validity of the Amendment.

         3. The Company has the requisite corporate power and authority to
execute and deliver the Amendment and to perform its obligations under the
Amendment and the Amended Note Purchase Agreement and the Notes.


                                  Exhibit B1-3
<PAGE>   22
         4. The Amendment has been duly authorized by all necessary corporate
action on the part of the Company, and has been executed and delivered by one or
more duly authorized officers of the Company. Each of the Amendment, the Amended
Note Purchase Agreement, the 1996 Warrant Agreement, as amended by the
Amendment, and the Notes is a valid and binding obligation of the Company,
enforceable against the Company in accordance with its terms.

         5. All consents, approvals and authorizations of, and all designations,
declarations, filings, registrations, qualifications and recordations with,
Federal, California, New York and Delaware Governmental Authorities required on
the part of the Company in connection with the execution and delivery of the
Amendment has been obtained.

         6. Except as set forth in Annex 3 hereto, to the best of our knowledge,
there are no material proceedings, actions or investigations pending against or
affecting the Company in any court or before any Governmental Authority or
arbitration board or tribunal.

         7. The execution and delivery of the Amendment and the performance by
the Company of the obligations under the Amendment, the Amended Note Purchase
Agreement, the 1996 Warrant Agreement, as amended by the Amendment, and the
Notes will not conflict with, constitute a violation of, result in a breach of
any provision of, constitute a default under, or result in the creation or
imposition of any Lien upon any of its Property pursuant to the Restated
Certificate of Incorporation or bylaws of the Company, any applicable statute,
rule, regulation, or, to the best of our knowledge, judgment or decree to which
the Company is subject.

         Each of the opinions set forth above is subject to the following
qualifications, assumptions, limitations and exceptions:

         (a) The opinions expressed above are subject to the effect of any
bankruptcy, insolvency, reorganization, fraudulent conveyance, preference,
equitable subordination, moratorium, bulk sales, marshalling or other similar
laws affecting the enforcement of creditors' rights generally.

         (b) The opinions expressed above are subject to the effect of general
principles of equity, whether applied by a court of law or equity.


                                  Exhibit B1 -4
<PAGE>   23
         (c) We express no opinion herein with respect to matters of local,
county or municipal law, or with respect to the laws, regulations or ordinances
of local agencies within the States of New York and California. Subject to the
foregoing, any reference herein to "law" means, unless specifically limited, the
Constitution, statutes and regulations of the States of New York and California
and the United States and judicial decisions of the courts thereof. Furthermore,
we express no opinion with respect to Federal or state anti-fraud or anti-trust
laws, or environmental or pollution control laws.

         (d) We express no opinion as to the enforceability of any provisions
contained in the Amendment, the Amended Note Purchase Agreement or the Notes (i)
providing for an increase in the rate of interest or imposing a late charge or
penalty in the event of delinquency or default, (ii) imposing a prepayment
charge, fee or penalty based upon a percentage or fraction of the amount prepaid
or the amount outstanding under the Amended Note Purchase Agreement and the
Notes, (iii) purporting to waive statutory rights, including the right to
receive notice or to be allowed to cure, reinstate or redeem in the event of a
default, (iv) purporting to allow any party to exercise any rights without
presentment, demand, protest or notice required by applicable law to any other
person or entity signatory thereto or bound thereby, (v) purporting to establish
evidentiary standards, (vi) providing for a waiver of the benefits of any
statute of limitations or any applicable bankruptcy or insolvency law or a
waiver of any rights under any applicable statues or rules hereafter enacted or
promulgated, or (vii) the enforceability of any provisions dictating the
governing law of the Amendment, the Amended Note Purchase Agreement and the
Notes.

         (e) The opinions expressed above are subject to the effect of judicial
decisions which may permit the introduction of extrinsic evidence to interpret
the terms of written contracts.

         (f) We express no opinion as to the enforceability under certain
circumstances or provisions which purport to indemnify a party against, or
require contributions toward, that party's liability for its own wrongful or
negligent act, or where indemnification or contribution is contrary to public
policy. In this regard, we advise you that in the opinion of the Securities and
Exchange Commission indemnification of directors, officers and controlling
persons of any issuer against liabilities 


                                  Exhibit B1-5
<PAGE>   24
arising under the Securities Act of 1933, as amended, is against public policy
and is therefore unenforceable.

         (g) The opinions expressed above are subject to the effect of generally
applicable rules of law that:

                  (i) limit or affect the enforcement of provisions of a
contract that purport to require waiver of the obligations of good faith, fair
dealing, diligence and reasonableness;

                  (ii) limit the availability of a remedy under certain
circumstances where another remedy has been elected;

                  (iii) limit the enforceability of provisions releasing,
exculpating or exempting a party from, or requiring indemnification of a party
for, liability for its own action or inaction, to the extent the action or
inaction involves gross negligence, recklessness, willful misconduct or unlawful
conduct;

                  (iv) govern and afford judicial discretion regarding the
determination of damages and entitlement to attorney fees and other costs;

                  (v) may permit a party who has materially failed to render or
offer performance required by the contract to cure that failure unless (A)
permitting a cure would unreasonably hinder the aggrieved party from making
substitute arrangements for performance, or (B) it was important in the
circumstance to the aggrieved party that performance occur by the date stated in
the contract; and

                  (vi) limit or affect the enforcement of provisions of a
contract purporting to restrict access to legal or equitable remedies.

         This opinion is rendered as of the date hereof, and we disclaim any
undertaking to advise you of changes in law or fact which may affect the
continued correctness of our opinion as of any later date. Except as otherwise
expressly set forth below, this opinion is rendered only to the Persons listed
on Annex 1 hereto, and is solely for their benefit in connection with the
transactions referenced herein. Future holders of the Notes may rely on this
opinion as if it were addressed to them. Our opinion is limited to the matters
stated herein, and no opinion is implied or may be inferred beyond the matters
expressly stated herein.


                                  Exhibit B1-6
<PAGE>   25
                                              Very truly yours,



                                              Brobeck, Phleger & Harrison LLP


                                  Exhibit B1 -7
<PAGE>   26
                                     ANNEX 1


                                     PART A

The Northwestern Mutual Life Insurance Company
720 East Wisconsin Avenue
Milwaukee, Wisconsin 53202

John Hancock Mutual Life Insurance Company
John Hancock Place
200 Clarendon Street
Boston, Massachusetts 02117

North Atlantic Smaller Companies Investment Trust PLC
c/o J.O. Hambro & Co., Ltd.
30 Queen Anne's Gate
London, England SW1H9AL


                                     PART B

Hebb & Gitlin
One State Street
Hartford, Connecticut 06103


                                    Annex 1-1
<PAGE>   27
                                     ANNEX 2

                       Foreign Good Standing Certificates


Oregon
California
New York
Pennsylvania


                                    Annex 2-1
<PAGE>   28
                                                                      EXHIBIT B2

                        FORM OF OPINION OF HEBB & GITLIN




                                                     December ___, 1996


To each of the Persons
listed in Annex 1 hereto

         Re:      The Cerplex Group, Inc., a Delaware corporation (the 
                  "Company")

Ladies and Gentlemen:

         Reference is made to the Waiver and Amendment Agreement dated December
9, 1996 (the "Amendment"), among the Company and each of the Persons listed on
Annex 1 hereto (the "Noteholders"), which waives and amends certain of the
provisions, as specified in the Amendment, of those certain Note Purchase
Agreements, each dated as of November 19, 1993, as amended (collectively, as in
effect immediately prior to the effectiveness of the Amendment, the "Existing
Note Purchase Agreement," and, as amended by the Amendment, the "Amended Note
Purchase Agreement"), between the Company and each of the Noteholders, relating
to, among other things, the purchase and sale of the Company's Series A 9.00%
Senior Subordinated Notes due November 19, 2001 (the "Notes"). The capitalized
terms used herein and not defined herein have the meanings specified in the
Amendment and the Amended Note Purchase Agreement, as the case may be.

         We have acted as special counsel to the Noteholders in connection with
the transactions contemplated by the Amendment. This opinion is being delivered
pursuant to Section 5.5 of the Amendment.

         In acting as such counsel, we have examined:

                  (a) an executed copy of the Existing Note Purchase Agreement;

                  (b) the Notes;

                  (c) an executed copy of the Amendment;


                                 Exhibit B2 - 1
<PAGE>   29
                  (d) an executed copy of the Warrant Agreement dated as of
         April 15, 1996 (the "1996 Warrant Agreement"), among the Company and
         each of the Noteholders;

                  (e) an executed certificate of a Senior Officer of the
         Company, delivered pursuant to Section 5.3 of the Amendment and an
         executed certificate of the Secretary of the Company, delivered
         pursuant to Section 5.4 of the Amendment;

                  (f) the opinion of Brobeck, Phleger & Harrison, counsel to the
         Company, dated the date hereof and delivered to you pursuant to Section
         5.5 of the Amendment; and

                  (k) originals, or copies certified or otherwise identified to
         our satisfaction, of such other documents, records, instruments and
         certificates of public officials as we have deemed necessary or
         appropriate to enable us to render this opinion.

         We have assumed the genuineness of all signatures and documents
submitted to us as originals, that all copies submitted to us conform to the
originals, the legal capacity of all natural Persons, and that each Person
executing documents had the power to enter into and perform its obligations
under such documents, and that such documents have been duly authorized,
executed and delivered by, and are binding upon and enforceable against, such
Persons.

         In rendering our opinion, we have relied, to the extent we deem
necessary and proper, on:

(A) warranties and representations as to certain factual matters contained in
the Amendment; and

                  (B) such opinion of Brobeck, Phleger & Harrison with respect
         to all questions

                           (i) governed by California law, and

                           (ii) concerning the due incorporation, valid
                  existence, good standing and corporate power and authority of,
                  and the authorization, execution and delivery of instruments
                  by, the Company (except that we have made an independent
                  examination of the 


                                 Exhibit B2 - 2
<PAGE>   30
                  certificate referred to above of the Secretary of the Company
                  setting forth its bylaws and corporate resolutions authorizing
                  its participation in the transactions contemplated by the
                  Amendment);

         based on such investigation as we have deemed appropriate, such opinion
         is satisfactory in form and scope to us and in our opinion the
         Noteholders and we are justified in relying thereon.

         Based on the foregoing, we are of the following opinions:

         1. The Company is a corporation duly incorporated, validly existing and
in good standing under the laws of the State of Delaware.

         2. The Company has the requisite corporate power and authority to
execute and deliver the Amendment and to perform its obligations thereunder.

         3. The Amendment has been duly authorized by all necessary corporate
action on the part of the Company and has been executed and delivered by one or
more duly authorized officers of the Company, and each of the Amendment, the
Amended Note Purchase Agreement, the 1996 Warrant Agreement, as amended by the
Amendment, and the Notes constitutes a legal, valid and binding obligation of
the Company, enforceable against the Company in accordance with its terms.

         4. No consents, approvals or authorizations of Governmental Authorities
are required under the laws of the United States of America or the State of New
York in connection with the execution and delivery by the Company of the
Amendment. Our opinion in this paragraph 4 is based solely on a review of
generally applicable laws of the United States of America and New York, and not
on any search with respect to, or review of, any orders, decrees, judgments or
other determinations specifically applicable to the Company.

         5. The execution and delivery of the Amendment and the performance by
the Company of its obligations under the Amendment, the Amended Note Purchase
Agreement, the 1996 Warrant Agreement, as amended by the Amendment, and the
Notes will not conflict with, constitute a violation of, result in a breach of
any provision of, constitute a default under, or result in the creation or
imposition of any Lien or encumbrance upon 


                                 Exhibit B2 - 3
<PAGE>   31
any of its Properties pursuant to the Restated Certificate of Incorporation or
bylaws of the Company.

         All opinions contained herein with respect to the enforceability of
documents and instruments are qualified to the extent that:

                  (a) the availability of equitable remedies, including, without
         limitation, specific enforcement and injunctive relief, is subject to
         the discretion of the court before which any proceedings therefor may
         be brought;

                  (b) the enforceability of certain terms provided in the
         Amendment, the Amended Note Purchase Agreement, the 1996 Warrant
         Agreement, as amended by the Amendment, and the Notes may be limited by
         applicable bankruptcy, reorganization, arrangement, insolvency,
         moratorium or similar laws affecting the enforcement of creditors'
         rights generally as at the time in effect; and

                  (c) rights to indemnification and contribution thereunder may
         be limited by applicable law or public policy.

         Except in reliance on such opinion of Brobeck, Phleger & Harrison, we
express no opinion as to the law of any jurisdiction other than the federal law
of the United States, the laws of the State of New York and the General
Corporation Law of the State of Delaware.

         Future holders of the Notes may rely on this opinion as if it were
addressed to them.

                                                     Very truly yours,


                                 Exhibit B2 - 4
<PAGE>   32
                                     ANNEX 1
                                   ADDRESSEES


The Northwestern Mutual Life Insurance Company
720 East Wisconsin Avenue
Milwaukee, Wisconsin 53202

John Hancock Mutual Life Insurance Company
John Hancock Place
200 Clarendon Street
Boston, Massachusetts 02117

North Atlantic Smaller Companies Trust PLC
c/o J.O. Hambro & Co., Ltd.
30 Queen Anne's Gate
London, England SW1H9AL