<PAGE>

                                                                     Exhibit 4.5
                                   $75,000,000


                          Compass Minerals Group, Inc.


                     10% Senior Subordinated Notes Due 2011


                          REGISTRATION RIGHTS AGREEMENT
                          -----------------------------


                                                                  April 10, 2002

Credit Suisse First Boston Corporation
J.P. Morgan Securities Inc.
Deutsche Bank Securities Inc.
Credit Lyonnais Securities (USA) Inc.
c/o Credit Suisse First Boston Corporation
    Eleven Madison Avenue
    New York, New York 10010-3629

Ladies and Gentlemen:

         Compass Minerals Group, Inc., a Delaware corporation (the "Issuer"),
proposes to issue and sell to Credit Suisse First Boston Corporation, J.P.
Morgan Securities Inc., Deutsche Bank Securities Inc. and Credit Lyonnais
Securities (USA) Inc. (collectively, the "Initial Purchasers"), upon the terms
set forth in a purchase agreement dated April 1, 2002 (the "Purchase
Agreement"), $75,000,000 aggregate principal amount of its 10% Senior
Subordinated Notes Due 2011 (the "Initial Securities") to be guaranteed (the
"Guaranties") by Carey Salt Company, Great Salt Lake Minerals Corporation, GSL
Corporation, NAMSCO Inc. and North American Salt Company, each a Delaware
Corporation, (the "Guarantors" and, collectively with the Issuer, the
"Company"). The Initial Securities will be issued pursuant to an Indenture,
dated as of November 28, 2001 (the "Indenture"), among the Issuer, the
Guarantors named therein and The Bank of New York , as trustee (the "Trustee").
As an inducement to the Initial Purchasers to enter into the Purchase Agreement,
the Company agrees with the Initial Purchasers, for the benefit of the Initial
Purchasers and the holders of the Securities (as defined below) (collectively
the "Holders"), as follows:

         1.  Registered Exchange Offer. Unless not permitted by applicable law
(after the Company has complied with the ultimate paragraph of this Section 1),
the Company shall prepare and, not later than 120 days (such 120th day being an
"Exchange Filing Deadline") after the date on which the Initial Purchasers
purchase the Initial Securities pursuant to the Pur-

<PAGE>

chase Agreement (the "Closing Date"), file with the Securities and Exchange
Commission (the "Commission") a registration statement (the "Exchange Offer
Registration Statement") on an appropriate form under the Securities Act of
1933, as amended (the "Securities Act"), with respect to a proposed offer (the
"Registered Exchange Offer") to the Holders of Transfer Restricted Securities
(as defined in Section 6 hereof), who are not prohibited by any law or policy of
the Commission from participating in the Registered Exchange Offer, to issue and
deliver to such Holders, in exchange for the Initial Securities, a like
aggregate principal amount of debt securities of the Company issued under the
Indenture, identical in all material respects to the Initial Securities and
registered under the Securities Act (the "Exchange Securities"). The Company
shall use its commercially reasonable efforts to (i) cause such Exchange Offer
Registration Statement to become effective under the Securities Act within 180
days after the Closing Date (such 180th day being an "Exchange Effectiveness
Deadline") and (ii) keep the Exchange Offer Registration Statement effective for
not less than 20 business days (or longer, if required by applicable law) after
the date notice of the Registered Exchange Offer is mailed to the Holders (such
period being called the "Exchange Offer Registration Period").

         If the Company commences the Registered Exchange Offer, the Company
will be required to consummate the Registered Exchange Offer no later than 210
days after the Closing Date (such 210th day being the "Consummation Deadline").

         Following the declaration of the effectiveness of the Exchange Offer
Registration Statement, the Company shall promptly commence the Registered
Exchange Offer, it being the objective of such Registered Exchange Offer to
enable each Holder of Transfer Restricted Securities electing to exchange the
Initial Securities for Exchange Securities (assuming that such Holder is not an
affiliate of the Company within the meaning of the Securities Act, acquires the
Exchange Securities in the ordinary course of such Holder's business and has no
arrangements with any person to participate in the distribution of the Exchange
Securities and is not prohibited by any law or policy of the Commission from
participating in the Registered Exchange Offer) to trade such Exchange
Securities from and after their receipt without any limitations or restrictions
under the Securities Act and without material restrictions under the securities
laws of the several states of the United States.

         The Company acknowledges that, pursuant to current interpretations by
the Commission's staff of Section 5 of the Securities Act, in the absence of an
applicable exemption therefrom, (i) each Holder which is a broker-dealer
electing to exchange Initial Securities, acquired for its own account as a
result of market making activities or other trading activities, for Exchange
Securities (an "Exchanging Dealer"), is required to deliver a prospectus
containing the information set forth in (a) Annex A hereto on the cover, (b)
Annex B hereto in the "Exchange Offer Procedures" section and the "Purpose of
the Exchange Offer" section, and (c) Annex C hereto in the "Plan of
Distribution" section of such prospectus in connection with a

                                       2

<PAGE>

sale of any such Exchange Securities received by such Exchanging Dealer pursuant
to the Registered Exchange Offer and (ii) an Initial Purchaser that elects to
sell Securities (as defined below) acquired in exchange for Initial Securities
constituting any portion of an unsold allotment, is required to deliver a
prospectus containing the information required by Items 507 or 508 of Regulation
S-K under the Securities Act, as applicable, in connection with such sale.

         The Company shall use its best efforts to keep the Exchange Offer
Registration Statement effective and to amend and supplement the prospectus
contained therein, in order to permit such prospectus to be lawfully delivered
by all persons subject to the prospectus delivery requirements of the Securities
Act for such period of time as such persons must comply with such requirements
in order to resell the Exchange Securities; provided, however, that (i) in the
                                            --------  -------
case where such prospectus and any amendment or supplement thereto must be
delivered by an Exchanging Dealer or an Initial Purchaser, such period shall be
the lesser of 180 days and the date on which all Exchanging Dealers and the
Initial Purchasers have sold all Exchange Securities held by them (unless such
period is extended pursuant to Section 3(j) below) and (ii) the Company shall
make such prospectus and any amendment or supplement thereto available to any
broker-dealer for use in connection with any resale of any Exchange Securities
for a period of not less than 180 days after the consummation of the Registered
Exchange Offer.

         If, upon consummation of the Registered Exchange Offer, any Initial
Purchaser holds Initial Securities acquired by it as part of its initial
distribution, the Company, simultaneously with the delivery of the Exchange
Securities pursuant to the Registered Exchange Offer, shall issue and deliver to
such Initial Purchaser upon the written request of such Initial Purchaser, in
exchange (the "Private Exchange") for the Initial Securities held by such
Initial Purchaser, a like principal amount of debt securities of the Company
issued under the Indenture and identical in all material respects to the Initial
Securities (the "Private Exchange Securities"). The Initial Securities, the
Exchange Securities and the Private Exchange Securities are herein collectively
called the "Securities".

         In connection with the Registered Exchange Offer, the Company shall:

               (a) mail to each Holder a copy of the prospectus forming part of
         the Exchange Offer Registration Statement, together with an appropriate
         letter of transmittal and related documents;

               (b) keep the Registered Exchange Offer open for not less than 20
         business days (or longer, if required by applicable law) after the date
         notice thereof is mailed to the Holders;

                                        3

<PAGE>
               (c) utilize the services of a depositary for the Registered
         Exchange Offer with an address in the Borough of Manhattan, The City of
         New York, which may be the Trustee or an affiliate of the Trustee;

               (d) permit Holders to withdraw tendered Securities at any time
         prior to the close of business, New York time, on the last business day
         on which the Registered Exchange Offer shall remain open; and

               (e) otherwise comply with all applicable laws.

         As soon as practicable after the close of the Registered Exchange Offer
or the Private Exchange, as the case may be, the Company shall:

               (x) accept for exchange all the Securities validly tendered and
         not withdrawn pursuant to the Registered Exchange Offer and the Private
         Exchange;

               (y) deliver to the Trustee for cancellation all the Initial
         Securities so accepted for exchange; and

               (z) cause the Trustee to authenticate and deliver promptly to
         each Holder of the Initial Securities, Exchange Securities or Private
         Exchange Securities, as the case may be, equal in principal amount to
         the Initial Securities of such Holder so accepted for exchange.

         The Indenture provides that the Exchange Securities will not be subject
to the transfer restrictions set forth in the Indenture and that all the
Securities will vote and consent together on all matters as one class and that
none of the Securities will have the right to vote or consent as a class
separate from one another on any matter.

         Interest on each Exchange Security and Private Exchange Security issued
pursuant to the Registered Exchange Offer and in the Private Exchange will
accrue from the last interest payment date on which interest was paid on the
Initial Securities surrendered in exchange therefor or, if no interest has been
paid on the Initial Securities, from the date of original issue of the Initial
Securities.

         Each Holder participating in the Registered Exchange Offer shall be
required to represent to the Company that at the time of the consummation of the
Registered Exchange Offer (i) any Exchange Securities received by such Holder
will be acquired in the ordinary course of business, (ii) such Holder will have
no arrangements or understanding with any person to participate in the
distribution of the Securities or the Exchange Securities within the meaning of
the Securities Act, (iii) such Holder is not an "affiliate," as defined in Rule
405 of the Securities Act, of the Company or if it is an affiliate, such Holder
will comply with the registration

                                       4

<PAGE>

and prospectus delivery requirements of the Securities Act to the extent
applicable, (iv) if such Holder is not a broker-dealer, that it is not engaged
in, and does not intend to engage in, the distribution of the Exchange
Securities and (v) if such Holder is a broker-dealer, that it will receive
Exchange Securities for its own account in exchange for Initial Securities that
were acquired as a result of market-making activities or other trading
activities and that it will be required to acknowledge that it will deliver a
prospectus in connection with any resale of such Exchange Securities.

         Notwithstanding any other provisions hereof, the Company will ensure
that (i) any Exchange Offer Registration Statement and any amendment thereto and
any prospectus forming part thereof and any supplement thereto complies in all
material respects with the Securities Act and the rules and regulations
thereunder, (ii) any Exchange Offer Registration Statement and any amendment
thereto does not, when it becomes effective, contain an untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein not misleading and (iii) any prospectus
forming part of any Exchange Offer Registration Statement, and any supplement to
such prospectus, does not include an untrue statement of a material fact or omit
to state a material fact required to be stated therein or necessary in order to
make the statements therein, in the light of the circumstances under which they
were made, not misleading.

         If following the date hereof there has been announced a change in
Commission policy with respect to exchange offers that in the reasonable opinion
of counsel to the Company raises a substantial question as to whether the
Registered Exchange Offer is permitted by applicable federal law, the Company
will seek a no-action letter or other favorable decision from the Commission
allowing the Company to consummate the Registered Exchange Offer. The Company
will pursue the issuance of such a decision to the Commission staff level. In
connection with the foregoing, the Company will take all such other actions as
may be requested by the Commission or otherwise required in connection with the
issuance of such decision, including without limitation (i) participating in
telephonic conferences with the Commission, (ii) delivering to the Commission
staff an analysis prepared by counsel to the Company setting forth the legal
bases, if any, upon which such counsel has concluded that the Registered
Exchange Offer should be permitted and (iii) diligently pursuing a resolution
(which need not be favorable) by the Commission staff.

         2. Shelf Registration. If, (i) because of any change in law or in
applicable interpretations thereof by the staff of the Commission, the Company
is not permitted to effect a Registered Exchange Offer, as contemplated by
Section 1 hereof, (ii) the Registered Exchange Offer is not consummated by the
210th day after the Closing Date, (iii) any Initial Purchaser so requests with
respect to the Initial Securities (or the Private Exchange Securities) not
eligible to be exchanged for Exchange Securities in the Registered Exchange
Offer and held by it following consummation of the Registered Exchange Offer or
(iv) any Holder (other than an

                                       5

<PAGE>

Exchanging Dealer) is not eligible to participate in the Registered Exchange
Offer or, in the case of any Holder (other than an Exchanging Dealer) that
participates in the Registered Exchange Offer, such Holder does not receive
freely tradeable Exchange Securities on the date of the exchange and any such
Holder so requests, the Company shall take the following actions (the date on
which any of the conditions described in the foregoing clauses (i) through (iv)
occur, including in the case of clauses (iii) or (iv) the receipt of the
required notice, being a "Trigger Date"):

               (a) The Company shall promptly (but in no event more than 120
         days after the Trigger Date (such 120th day being a "Shelf Filing
         Deadline," each of the Exchange Filing Deadline and the Shelf Filing
         Deadline, a "Filing Deadline") file with the Commission and thereafter
         use commercially reasonable efforts to cause to be declared effective
         no later than 180 days after the Trigger Date (such 180th day being a
         "Shelf Effectiveness Deadline," each of the Exchange Effectiveness
         Deadline and the Shelf Effectiveness Deadline, an "Effectiveness
         Deadline") a registration statement (the "Shelf Registration Statement"
         and, together with the Exchange Offer Registration Statement, a
         "Registration Statement") on an appropriate form under the Securities
         Act relating to the offer and sale of the Transfer Restricted
         Securities by the Holders thereof from time to time in accordance with
         the methods of distribution set forth in the Shelf Registration
         Statement and Rule 415 under the Securities Act (hereinafter, the
         "Shelf Registration"); provided, however, that no Holder (other than an
                                --------  -------
         Initial Purchaser) shall be entitled to have the Securities held by it
         covered by such Shelf Registration Statement unless such Holder agrees
         in writing to be bound by all the provisions of this Agreement
         applicable to such Holder.

               (b) The Company shall use its best efforts to keep the Shelf
         Registration Statement continuously effective in order to permit the
         prospectus included therein to be lawfully delivered by the Holders of
         the relevant Securities, for a period of two years (or for such longer
         period if extended pursuant to Section 3(j) below) from the date of its
         effectiveness or such shorter period that will terminate when all the
         Securities covered by the Shelf Registration Statement (i) have been
         sold pursuant thereto or (ii) are no longer restricted securities (as
         defined in Rule 144 under the Securities Act, or any successor rule
         thereof). The Company shall be deemed not to have used its best efforts
         to keep the Shelf Registration Statement effective during the requisite
         period if it voluntarily takes any action that would result in Holders
         of Securities covered thereby not being able to offer and sell such
         Securities during that period, unless such action is required by
         applicable law.

               (c) Notwithstanding any other provisions of this Agreement to the
         contrary, the Company shall cause the Shelf Registration Statement and
         the related prospectus and any amendment or supplement thereto, as of
         the effective date of the Shelf Regis-

                                        6

<PAGE>

         tration Statement, amendment or supplement, (i) to comply in all
         material respects with the applicable requirements of the Securities
         Act and the rules and regulations of the Commission and (ii) not to
         contain any untrue statement of a material fact or omit to state a
         material fact required to be stated therein or necessary in order to
         make the statements therein, in light of the circumstances under which
         they were made, not misleading.

         3.   Registration Procedures. In connection with any Shelf Registration
contemplated by Section 2 hereof and, to the extent applicable, any Registered
Exchange Offer contemplated by Section 1 hereof, the following provisions shall
apply:

              (a) The Company shall (i) furnish to each Initial Purchaser, prior
         to the filing thereof with the Commission, a copy of the Registration
         Statement and each amendment thereof and each supplement, if any, to
         the prospectus included therein and, in the event that an Initial
         Purchaser (with respect to any portion of an unsold allotment from the
         original offering) is participating in the Registered Exchange Offer or
         the Shelf Registration Statement, the Company shall use its best
         efforts to reflect in each such document, when so filed with the
         Commission, such comments as such Initial Purchaser reasonably may
         propose; (ii) include the information set forth in Annex A hereto on
         the cover, in Annex B hereto in the "Exchange Offer Procedures" section
         and the "Purpose of the Exchange Offer" section and in Annex C hereto
         in the "Plan of Distribution" section of the prospectus forming a part
         of the Exchange Offer Registration Statement and include the
         information set forth in Annex D hereto in the Letter of Transmittal
         delivered pursuant to the Registered Exchange Offer; (iii) if requested
         by an Initial Purchaser, include the information required by Items 507
         or 508 of Regulation S-K under the Securities Act, as applicable, in
         the prospectus forming a part of the Exchange Offer Registration
         Statement; (iv) include within the prospectus contained in the Exchange
         Offer Registration Statement a section entitled "Plan of Distribution,"
         reasonably acceptable to the Initial Purchasers, which shall contain a
         summary statement of the positions taken or policies made by the staff
         of the Commission with respect to the potential "underwriter" status of
         any broker-dealer that is the beneficial owner (as defined in Rule
         13d-3 under the Securities Exchange Act of 1934, as amended (the
         "Exchange Act")) of Exchange Securities received by such broker-dealer
         in the Registered Exchange Offer (a "Participating Broker-Dealer"),
         whether such positions or policies have been publicly disseminated by
         the staff of the Commission or such positions or policies, in the
         reasonable judgment of the Initial Purchasers based upon advice of
         counsel (which may be in-house counsel), represent the prevailing views
         of the staff of the Commission; and (v) in the case of a Shelf
         Registration Statement, include the names of the Holders who propose to
         sell Securities pursuant to the Shelf Registration Statement as selling
         securityholders.

                                        7

<PAGE>

               (b) The Company shall give written notice to the Initial
         Purchasers, the Holders of the Securities and any Participating
         Broker-Dealer from whom the Company has received prior written notice
         that it will be a Participating Broker-Dealer in the Registered
         Exchange Offer (which notice pursuant to clauses (ii)-(v) hereof shall
         be accompanied by an instruction to suspend the use of the prospectus
         until the requisite changes have been made):

                   (i)   when the Registration Statement or any amendment
               thereto has been filed with the Commission and when the
               Registration Statement or any post-effective amendment thereto
               has become effective;

                   (ii)  of any request by the Commission for amendments or
               supplements to the Registration Statement or the prospectus
               included therein or for additional information;

                   (iii) of the issuance by the Commission of any stop order
               suspending the effectiveness of the Registration Statement or the
               initiation of any proceedings for that purpose;

                   (iv)  of the receipt by the Company or its legal counsel of
               any notification with respect to the suspension of the
               qualification of the Securities for sale in any jurisdiction or
               the initiation or threatening of any proceeding for such purpose;
               and

                   (v)   of the happening of any event that requires the Company
               to make changes in the Registration Statement or the prospectus
               in order that the Registration Statement or the prospectus do not
               contain an untrue statement of a material fact nor omit to state
               a material fact required to be stated therein or necessary to
               make the statements therein (in the case of the prospectus, in
               light of the circumstances under which they were made) not
               misleading.

               (c) The Company shall make every reasonable effort to obtain the
         withdrawal at the earliest possible time, of any order suspending the
         effectiveness of the Registration Statement.

               (d) The Company shall furnish to each Holder of Securities
         included within the coverage of the Shelf Registration, without charge,
         at least one copy of the Shelf Registration Statement and any
         post-effective amendment thereto, including financial statements and
         schedules, and, if the Holder so requests in writing, all exhibits
         thereto (including those, if any, incorporated by reference).

                                       8

<PAGE>

               (e) The Company shall deliver to each Exchanging Dealer and each
         Initial Purchaser, and to any other Holder who so requests, without
         charge, at least one copy of the Exchange Offer Registration Statement
         and any post-effective amendment thereto, including financial
         statements and schedules, and, if any Initial Purchaser or any such
         Holder requests, all exhibits thereto (including those incorporated by
         reference).

               (f) The Company shall, during the Shelf Registration Period,
         deliver to each Holder of Securities included within the coverage of
         the Shelf Registration, without charge, as many copies of the
         prospectus (including each preliminary prospectus) included in the
         Shelf Registration Statement and any amendment or supplement thereto as
         such person may reasonably request. The Company consents, subject to
         the provisions of this Agreement, to the use of the prospectus or any
         amendment or supplement thereto by each of the selling Holders of the
         Securities in connection with the offering and sale of the Securities
         covered by the prospectus, or any amendment or supplement thereto,
         included in the Shelf Registration Statement.

               (g) The Company shall deliver to each Initial Purchaser, any
         Exchanging Dealer, any Participating Broker-Dealer and such other
         persons required to deliver a prospectus following the Registered
         Exchange Offer, without charge, as many copies of the final prospectus
         included in the Exchange Offer Registration Statement and any amendment
         or supplement thereto as such persons may reasonably request. The
         Company consents, subject to the provisions of this Agreement, to the
         use of the prospectus or any amendment or supplement thereto by any
         Initial Purchaser, if necessary, any Participating Broker-Dealer and
         such other persons required to deliver a prospectus following the
         Registered Exchange Offer in connection with the offering and sale of
         the Exchange Securities covered by the prospectus, or any amendment or
         supplement thereto, included in such Exchange Offer Registration
         Statement.

               (h) Prior to any public offering of the Securities pursuant to
         any Registration Statement the Company shall register or qualify or
         cooperate with the Holders of the Securities included therein and their
         respective counsel in connection with the registration or qualification
         of the Securities for offer and sale under the securities or "blue sky"
         laws of such states of the United States as any Holder of the
         Securities reasonably requests in writing and do any and all other acts
         or things necessary or advisable to enable the offer and sale in such
         jurisdictions of the Securities covered by such Registration Statement;
         provided, however, that the Company shall not be required to (i)
         --------  -------
         qualify generally to do business in any jurisdiction where it is not
         then so qualified or (ii) take any action which would subject it to
         general service of process or to taxation in any jurisdiction where it
         is not then so subject.

                                       9

<PAGE>

               (i) The Company shall cooperate with the Holders of the
         Securities to facilitate the timely preparation and delivery of
         certificates representing the Securities to be sold pursuant to any
         Registration Statement free of any restrictive legends and in such
         denominations and registered in such names as the Holders may request a
         reason able period of time prior to sales of the Securities pursuant to
         such Registration Statement.

               (j) Upon the occurrence of any event contemplated by paragraphs
         (ii) through (v) of Section 3(b) above during the period for which the
         Company is required to maintain an effective Registration Statement,
         the Company shall promptly prepare and file a post-effective amendment
         to the Registration Statement or a supplement to the related prospectus
         and any other required document so that, as thereafter delivered to
         Holders of the Securities or purchasers of Securities, the prospectus
         will not contain an untrue statement of a material fact or omit to
         state any material fact required to be stated therein or necessary to
         make the statements therein, in light of the circumstances under which
         they were made, not misleading. If the Company notifies the Initial
         Purchasers, the Holders of the Securities and any known Participating
         Broker-Dealer in accordance with paragraphs (ii) through (v) of Section
         3(b) above to suspend the use of the prospectus until the requisite
         changes to the prospectus have been made, then the Initial Purchasers,
         the Holders of the Securities and any such Participating Broker-Dealers
         shall suspend use of such prospectus, and the period of effectiveness
         of the Shelf Registration Statement provided for in Section 2(b) above
         and the Exchange Offer Registration Statement provided for in Section 1
         above shall each be extended by the number of days from and including
         the date of the giving of such notice to and including the date when
         the Initial Purchasers, the Holders of the Securities and any known
         Participating Broker-Dealer shall have received such amended or
         supplemented prospectus pursuant to this Section 3(j). Notwithstanding
         the foregoing, the Company may suspend the offering and sales under the
         Exchange Offer Registration Statement subsequent to the consummation of
         the Registered Exchange Offer or the Shelf Registration Statement for
         up to 90 days in each year during which such Exchange Offer
         Registration Statement is required to be effective and usable hereunder
         subsequent to the consummation of the Registered Exchange Offer or such
         Shelf Registration Statement is required to be effective and usable
         hereunder (measured from the date of effectiveness of such Shelf
         Registration Statement to successive anniversaries thereof) if (A)
         either (x)(I) the Company shall be engaged in a material acquisition or
         disposition and (II)(aa) such acquisition or disposition is required to
         be disclosed in the Exchange Offer Registration Statement or the Shelf
         Registration Statement, the related prospectus or any amendment or
         supplement thereto, or the failure by the Company to disclose such
         transaction in the Exchange Offer Registration Statement or the Shelf
         Registration Statement or related prospectus, or any amendment or
         supplement thereto, as then amended or supplemented, would cause such
         Exchange Offer Registration

                                       10

<PAGE>

         Statement or Shelf Registration Statement, prospectus or amendment or
         supplement thereto, to contain an untrue statement of material fact or
         omit to state a material fact necessary in order to make the statements
         therein not misleading, in light of the circumstances under which they
         were made, (bb) information regarding the existence of such acquisition
         or disposition has not then been publicly disclosed by or on behalf of
         the Company and (cc) a majority of the Board of Directors of the
         Company determines in the exercise of its good faith judgment that
         disclosure of such acquisition or disposition would not be in the best
         interest of the Company or would have a material adverse effect on the
         consummation of such acquisition or disposition or (y) a majority of
         the Board of Directors of the Company determines in the exercise of its
         good faith judgment that compliance with the disclosure obligations set
         forth in this Section 3(j) would otherwise have a material adverse
         effect on the Company and its subsidiaries, taken as a whole, and (B)
         the Company notifies the Holders within two business days after such
         Board of Directors makes the relevant determination set forth in clause
         (A); provided, however, that in each such case the applicable period of
         effectiveness of the Shelf Registration Statement provided for in
         Section 2(b) above and the Exchange Offer Registration Statement
         provided for in Section 1 above shall each be extended by the number of
         days during which such effectiveness was suspended pursuant to the
         foregoing and Additional Interest shall not apply during any period the
         Company is permitted to suspend offerings and sales under this
         sentence.

               (k) Not later than the effective date of the applicable
         Registration Statement, the Company will provide a CUSIP number for the
         Initial Securities, the Exchange Securities or the Private Exchange
         Securities, as the case may be, and provide the applicable trustee with
         printed certificates for the Initial Securities, the Exchange
         Securities or the Private Exchange Securities, as the case may be, in a
         form eligible for deposit with The Depository Trust Company.

               (l) The Company will comply with all rules and regulations of the
         Commission to the extent and so long as they are applicable to the
         Registered Exchange Offer or the Shelf Registration and will make
         generally available to its security holders (or otherwise provide in
         accordance with Section 11(a) of the Securities Act) an earnings
         statement satisfying the provisions of Section 11(a) of the Securities
         Act, no later than 45 days after the end of a 12-month period (or 90
         days, if such period is a fiscal year) beginning with the first month
         of the Company's first fiscal quarter commencing after the effective
         date of the Registration Statement, which statement shall cover such
         12-month period.

               (m) The Company shall cause the Indenture to be qualified under
         the Trust Indenture Act of 1939, as amended, in a timely manner and
         containing such changes, if any, as shall be necessary for such
         qualification. In the event that such qualification

                                       11

<PAGE>

         would require the appointment of a new trustee under the Indenture, the
         Company shall appoint a new trustee thereunder pursuant to the
         applicable provisions of the Indenture.

               (n) The Company may require each Holder of Securities to be sold
         pursuant to the Shelf Registration Statement to furnish to the Company
         such information regarding the Holder and the distribution of the
         Securities as the Company may from time to time reasonably require for
         inclusion in the Shelf Registration Statement, and the Company may
         exclude from such registration the Securities of any Holder that
         unreasonably fails to furnish such information within a reasonable time
         after receiving such request.

               (o) The Company shall enter into such customary agreements and
         take all such other action, if any, as any Holder of the Securities
         shall reasonably request in order to facilitate the disposition of the
         Securities pursuant to any Shelf Registration.

               (p) In the case of any Shelf Registration, the Company shall (i)
         make reasonably available for inspection by the Holders of the
         Securities, any attorney, accountant or other advisor retained by the
         Holders of the Securities all relevant financial and other records,
         pertinent corporate documents and properties of the Company and (ii)
         cause the Company's officers, directors, employees, accountants and
         auditors to supply all relevant information reasonably requested by the
         Holders of the Securities, attorney, accountant or advisor in
         connection with the Shelf Registration Statement, in each case, as
         shall be reasonably necessary to enable such persons, to conduct a
         reasonable investigation within the meaning of Section 11 of the
         Securities Act; provided, however, that the foregoing inspection and
                         --------  -------
         information gathering shall be coordinated on behalf of the Initial
         Purchasers by you and on behalf of the other parties, by one counsel
         designated by and on behalf of such other parties as described in
         Section 4 hereof.

               (q) In the case of any Shelf Registration, the Company, if
         requested by any Holder of Securities covered thereby, shall cause (i)
         its counsel to deliver an opinion relating to the Securities in
         customary form addressed to such Holders and dated the effective date
         of such Shelf Registration Statement (it being agreed that the matters
         to be covered by such opinion shall include, without limitation, the
         due incorporation and good standing of the Company and its
         subsidiaries; the qualification of the Company and its subsidiaries to
         transact business as foreign corporations; the due authorization,
         execution and delivery of the relevant agreement of the type referred
         to in Section 3(o) hereof; the due authorization, execution,
         authentication and issuance, and the validity and enforceability, of
         the applicable Securities; the absence of material legal or
         governmental proceedings involving the Company and its subsidiaries;
         the absence of

                                       12

<PAGE>

         governmental approvals required to be obtained in connection with the
         Shelf Registration Statement, the offering and sale of the applicable
         Securities, or any agreement of the type referred to in Section 3(o)
         hereof; the compliance as to form of such Shelf Registration Statement
         and any documents incorporated by reference therein and of the
         Indenture with the requirements of the Securities Act and the Trust
         Indenture Act, respectively; and, as of the date of the opinion and as
         of the effective date of the Shelf Registration Statement or most
         recent post-effective amendment thereto, as the case may be, the
         absence from such Shelf Registration Statement and the prospectus
         included therein, as then amended or supplemented, and from any
         documents incorporated by reference therein of an untrue statement of a
         material fact or the omission to state therein a material fact required
         to be stated therein or necessary to make the statements therein not
         misleading (in the case of any such documents, in the light of the
         circumstances existing at the time that such documents were filed with
         the Commission under the Exchange Act), all in the manner covered by
         the opinion of Latham & Watkins delivered to the Purchasers on the date
         hereof and (ii) its independent public accountants to provide to the
         selling Holders of the applicable Securities a comfort letter in
         customary form and covering matters of the type customarily covered in
         comfort letters to selling security holders in a shelf registration,
         subject to receipt of appropriate documentation as contemplated, and
         only if permitted, by Statement of Auditing Standards No. 72.

              (r) If a Registered Exchange Offer or a Private Exchange is to be
         consummated, upon delivery of the Initial Securities by Holders to the
         Company (or to such other Person as directed by the Company) in
         exchange for the Exchange Securities or the Private Exchange
         Securities, as the case may be, the Company shall mark, or caused to be
         marked, on the Initial Securities so exchanged that such Initial
         Securities are being canceled in exchange for the Exchange Securities
         or the Private Exchange Securities, as the case may be; in no event
         shall the Initial Securities be marked as paid or otherwise satisfied.

              (s) The Company shall use its reasonable efforts to take all
         other steps necessary to effect the registration of the Securities
         covered by a Registration Statement contemplated hereby.

         4.   Registration Expenses. (a) All expenses incident to the Company's
performance of and compliance with this Agreement will be borne by the Company,
regardless of whether a Registration Statement is ever filed or becomes
effective, including without limitation;

              (i)    all registration and filing fees and expenses;

                                       13

<PAGE>

                   (ii)  all fees and expenses of compliance with federal
              securities and state "blue sky" or securities laws;

                   (iii) all expenses of printing (including printing
              certificates for the Securities to be issued in the Registered
              Exchange Offer and the Private Exchange and printing of
              Prospectuses), messenger and delivery services and telephone;

                   (iv)  all fees and disbursements of counsel for the Company;

                   (v)   all application and filing fees in connection with
              listing the Exchange Securities on a national securities exchange
              or automated quotation system pursuant to the requirements hereof;
              and

                   (vi)  all fees and disbursements of independent certified
              public accountants of the Company (including the expenses of any
              special audit and comfort letters required by or incident to such
              performance).

The Company will bear its internal expenses (including, without limitation, all
salaries and expenses of its officers and employees performing legal or
accounting duties), the expenses of any annual audit and the fees and expenses
of any person, including special experts, retained by the Company.

         (b)  In connection with any Registration Statement required by this
Agreement, the Company will reimburse the Initial Purchasers and the Holders of
Transfer Restricted Securities who are tendering Initial Securities in the
Registered Exchange Offer and/or selling or reselling Securities pursuant to the
"Plan of Distribution" contained in the Exchange Offer Registration Statement or
the Shelf Registration Statement, as applicable, for the reasonable fees and
disbursements of not more than one counsel, who shall be Cahill Gordon &
Reindel.

         5.   Indemnification. (a) The Company agrees to indemnify and hold
harmless each Holder of the Securities, any Participating Broker-Dealer and each
person, if any, who controls such Holder or such Participating Broker-Dealer
within the meaning of the Securities Act or the Exchange Act (each Holder, any
Participating Broker-Dealer and such controlling persons are each referred to as
an "Indemnified Party" and, collectively as the "Indemnified Parties") from and
against any losses, claims, damages or liabilities, joint or several, or any
actions in respect thereof (including, but not limited to, any losses, claims,
damages, liabilities or actions relating to purchases and sales of the
Securities) to which each Indemnified Party may become subject under the
Securities Act, the Exchange Act or otherwise, insofar as such losses, claims,
damages, liabilities or actions arise out of or are based upon any untrue
statement or alleged untrue statement of a material fact contained in a
Registration Statement or prospectus or in any amendment or supplement thereto
or in any preliminary prospectus relat-

                                       14

<PAGE>

ing to a Shelf Registration, or arise out of, or are based upon, the omission or
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, and shall reimburse,
as incurred, the Indemnified Parties for any legal or other expenses reasonably
incurred by them in connection with investigating or defending any such loss,
claim, damage, liability or action in respect thereof; provided, however, that
                                                       --------  -------
(i) the Company shall not be liable in any such case to the extent that such
loss, claim, damage or liability arises out of or is based upon any untrue
statement or alleged untrue statement or omission or alleged omission made in a
Registration Statement or prospectus or in any amendment or supplement thereto
or in any preliminary prospectus relating to a Shelf Registration in reliance
upon and in conformity with written information pertaining to such Holder and
furnished to the Company by or on behalf of such Holder specifically for
inclusion therein and (ii) with respect to any untrue statement or omission or
alleged untrue statement or omission made in any preliminary prospectus relating
to a Shelf Registration Statement, the indemnity agreement contained in this
subsection (a) shall not inure to the benefit of any Holder or Participating
Broker-Dealer from whom the person asserting any such losses, claims, damages or
liabilities purchased the Securities concerned, to the extent that a prospectus
relating to such Securities was required to be delivered by such Holder or
Participating Broker-Dealer under the Securities Act in connection with such
purchase and any such loss, claim, damage or liability of such Holder or
Participating Broker-Dealer results from the fact that there was not sent or
given to such person, at or prior to the written confirmation of the sale of
such Securities to such person, a copy of the final prospectus if the Company
had previously furnished copies thereof to such Holder or Participating
Broker-Dealer; provided further, however, that this indemnity agreement will be
               -------- -------  -------
in addition to any liability which the Company may otherwise have to such
Indemnified Party. The Company shall also indemnify underwriters, their officers
and directors and each person who controls such underwriters within the meaning
of the Securities Act or the Exchange Act to the same extent as provided above
with respect to the indemnification of the Holders of the Securities if
requested by such Holders. Any amounts advanced by the Company to an Indemnified
Party pursuant to this Section 5 as a result of any losses described herein
shall be returned to the Company if it shall be finally determined by a court of
competent jurisdiction in a judgment not subject to appeal or further review
that such Indemnified Party was not entitled to such indemnification by the
Company.

         (b) Each Holder of the Securities, severally and not jointly, will
indemnify and hold harmless the Company and each person, if any, who controls
the Company within the meaning of the Securities Act or the Exchange Act from
and against any losses, claims, damages or liabilities or any actions in respect
thereof, to which the Company or any such controlling person may become subject
under the Securities Act, the Exchange Act or otherwise, insofar as such losses,
claims, damages, liabilities or actions arise out of or are based upon any
untrue statement or alleged untrue statement of a material fact contained in a
Registration Statement or prospectus or in any amendment or supplement thereto
or in any preliminary prospectus relating to a Shelf Registration, or arise out
of or are based upon the omission or alleged omission to state therein a
material fact necessary to make the statements therein not misleading, but in
each case only to the extent that the untrue statement or omission or

                                       15

<PAGE>

alleged untrue statement or omission was made in reliance upon and in conformity
with written information pertaining to such Holder and furnished to the Company
by or on behalf of such Holder specifically for inclusion therein; and, subject
to the limitation set forth immediately preceding this clause, shall reimburse,
as incurred, the Company for any legal or other expenses reasonably incurred by
the Company or any such controlling person in connection with investigating or
defending any loss, claim, damage, liability or action in respect thereof. This
indemnity agreement will be in addition to any liability which such Holder may
otherwise have to the Company or any of its controlling persons.

         (c) Promptly after receipt by an Indemnified Party under this Section 5
of notice of the commencement of any action or proceeding (including a
governmental investigation), such Indemnified Party will, if a claim in respect
thereof is to be made against the indemnifying party under this Section 5,
notify the indemnifying party of the commencement thereof; but the omission so
to notify the indemnifying party will not, in any event, relieve the
indemnifying party from any obligations to any Indemnified Party other than the
indemnification obligation provided in paragraph (a) or (b) above. In case any
such action is brought against any Indemnified Party, and it notifies the
indemnifying party of the commencement thereof, the indemnifying party will be
entitled to participate therein and, to the extent that it may wish, jointly
with any other indemnifying party similarly notified, to assume the defense
thereof, with counsel reasonably satisfactory to such Indemnified Party (who
shall not, except with the consent of the Indemnified Party, be counsel to the
indemnifying party), and after notice from the indemnifying party to such
Indemnified Party of its election so to assume the defense thereof the
indemnifying party will not be liable to such Indemnified Party under this
Section 5 for any legal or other expenses, other than reasonable costs of
investigation, subsequently incurred by such Indemnified Party in connection
with the defense thereof. In no event shall the indemnifying party be liable for
fees and expenses of more than one counsel (in addition to any local counsel)
separate from its own counsel for the Indemnified Party in connection with any
one action or separate but related actions in the same jurisdiction arising out
of the same general allegations or circumstances. No indemnifying party shall,
without the prior written consent of the Indemnified Party, effect any
settlement of any pending or threatened action in respect of which any
Indemnified Party is or could have been a party and indemnity could have been
sought hereunder by such Indemnified Party unless such settlement includes an
unconditional release of such Indemnified Party from all liability on any claims
that are the subject matter of such action, and does not include a statement as
to or an admission of fault, culpability or a failure to act by or on behalf of
any Indemnified Party.

         (d) If the indemnification provided for in this Section 5 is
unavailable or insufficient to hold harmless an Indemnified Party under
subsections (a) or (b) above, then each indemnifying party shall contribute to
the amount paid or payable by such Indemnified Party as

                                       16

<PAGE>

a result of the losses, claims, damages or liabilities (or actions in respect
thereof) referred to in subsection (a) or (b) above (i) in such proportion as is
appropriate to reflect the relative benefits received by the indemnifying party
or parties on the one hand and the Indemnified Party on the other from the
exchange of the Securities, pursuant to the Registered Exchange Offer, or (ii)
if the allocation provided by the foregoing clause (i) is not permitted by
applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause (i) above but also the relative fault of
the indemnifying party or parties on the one hand and the Indemnified Party on
the other in connection with the statements or omissions that resulted in such
losses, claims, damages or liabilities (or actions in respect thereof) as well
as any other relevant equitable considerations. The relative fault of the
parties shall be determined by reference to, among other things, whether the
untrue or alleged untrue statement of a material fact or the omission or alleged
omission to state a material fact relates to information supplied by the Company
on the one hand or such Holder or such other Indemnified Party, as the case may
be, on the other, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The amount paid by an Indemnified Party as a result of the losses, claims,
damages or liabilities referred to in the first sentence of this subsection (d)
shall be deemed to include any legal or other expenses reasonably incurred by
such Indemnified Party in connection with investigating or defending any action
or claim which is the subject of this subsection (d). Notwithstanding any other
provision of this Section 5(d), the Holders of the Securities shall not be
required to contribute any amount in excess of the amount by which the net
proceeds received by such Holders from the sale of the Securities pursuant to a
Registration Statement exceeds the amount of damages which such Holders have
otherwise been required to pay by reason of such untrue or alleged untrue
statement or omission or alleged omission. No person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation. For purposes of this paragraph (d), each person,
if any, who controls such Indemnified Party within the meaning of the Securities
Act or the Exchange Act shall have the same rights to contribution as such
Indemnified Party and each person, if any, who controls the Company within the
meaning of the Securities Act or the Exchange Act shall have the same rights to
contribution as the Company.

         (e) The agreements contained in this Section 5 shall survive the sale
of the Securities pursuant to a Registration Statement and shall remain in full
force and effect, regardless of any termination or cancellation of this
Agreement or any investigation made by or on behalf of any Indemnified Party.

         6.  Additional Interest Under Certain Circumstances. (a) Additional
interest (the "Additional Interest") with respect to the Securities shall be
assessed as follows if any of the following events occur (each such event in
clauses (i) through (iv) below being herein called a "Registration Default"):

                                       17

<PAGE>

                   (i)   any Registration Statement required by this Agreement
              is not filed with the Commission on or prior to the applicable
              Filing Deadline;

                   (ii)  any Registration Statement required by this Agreement
              is not declared effective by the Commission on or prior to the
              applicable Effectiveness Deadline;

                   (iii) the Registered Exchange Offer has not been consummated
              on or prior to the Consummation Deadline; or

                   (iv)  any Registration Statement required by this Agreement
              has been declared effective by the Commission but (A) such
              Registration Statement thereafter ceases to be effective or (B)
              such Registration Statement or the related prospectus ceases to be
              usable in connection with resales of Transfer Restricted
              Securities during the periods specified herein because either (1)
              any event occurs as a result of which the related prospectus
              forming part of such Registration Statement would include any
              untrue statement of a material fact or omit to state any material
              fact necessary to make the statements therein in the light of the
              circumstances under which they were made not misleading, or (2) it
              shall be necessary to amend such Registration Statement or
              supplement the related prospectus, to comply with the Securities
              Act or the Exchange Act or the respective rules thereunder;
              provided, however, the Registration Default referred to in this
              Section 6(a)(iv) shall be deemed not to have occurred and to be
              continuing, and Additional Interest shall not accrue, during any
              period the Company is permitted to suspend offerings and sales
              pursuant to Section 3(j).

Each of the foregoing will constitute a Registration Default whatever the reason
for any such event and whether it is voluntary or involuntary or is beyond the
control of the Company or pursuant to operation of law or as a result of any
action or inaction by the Commission.

         Additional Interest shall accrue on the Securities over and above the
interest set forth in the title of the Securities from and including the date on
which any such Registration Default shall occur to but excluding the date on
which all such Registration Defaults have been cured, at a rate of 0.25% per
annum (the "Additional Interest Rate") for the first 90-day period immediately
following the occurrence of such Registration Default. The Additional Interest
Rate shall increase by an additional 0.25% per annum with respect to each
subsequent 90-day period until all Registration Defaults have been cured, up to
a maximum Additional Interest Rate of 1.0% per annum.

                                       18

<PAGE>

         (b) A Registration Default referred to in Section 6(a)(iv) hereof shall
be deemed not to have occurred and be continuing in relation to a Shelf
Registration Statement or the related prospectus if (i) such Registration
Default has occurred solely as a result of (x) the filing of a post-effective
amendment to such Shelf Registration Statement to incorporate annual audited
financial information with respect to the Company where such post-effective
amendment is not yet effective and needs to be declared effective to permit
Holders to use the related prospectus or (y) other material events, with respect
to the Company that would need to be described in such Shelf Registration
Statement or the related prospectus and (ii) in the case of clause (y), the
Company is proceeding promptly and in good faith to amend or supplement such
Shelf Registration Statement and related prospectus to describe such events;
provided, however, that in any case if such Registration Default occurs for a
--------  -------
continuous period in excess of 30 days, Additional Interest shall be payable in
accordance with the above paragraph from the day such Registration Default
occurs until such Registration Default is cured.

         (c) Any amounts of Additional Interest due pursuant to Section 6(a)
will be payable in cash on the regular interest payment dates with respect to
the Securities. The amount of Additional Interest will be determined by
multiplying the applicable Additional Interest Rate by the principal amount of
the Securities and further multiplied by a fraction, the numerator of which is
the number of days such Additional Interest Rate was applicable during such
period (determined on the basis of a 360-day year comprised of twelve 30-day
months), and the denominator of which is 360.

         (d) "Transfer Restricted Securities" means each Security until (i) the
date on which such Security has been exchanged by a person other than a
broker-dealer for a freely transferable Exchange Security in the Registered
Exchange Offer, (ii) following the exchange by a broker-dealer in the Registered
Exchange Offer of an Initial Security for an Exchange Note, the date on which
such Exchange Note is sold to a purchaser who receives from such broker-dealer
on or prior to the date of such sale a copy of the prospectus contained in the
Exchange Offer Registration Statement, (iii) the date on which such Security has
been effectively registered under the Securities Act and disposed of in
accordance with the Shelf Registration Statement or (iv) the date on which such
Security is distributed to the public pursuant to Rule 144 under the Securities
Act or is saleable pursuant to Rule 144(k) under the Securities Act.

         7.  Rules 144 and 144A. The Company shall use its best efforts to file
the reports required to be filed by it under the Securities Act and the Exchange
Act in a timely manner and, if at any time the Company is not required to file
such reports, it will, upon the request of any Holder of Securities, make
available other information to the extent necessary to permit sales of their
securities pursuant to Rules 144 and 144A. The Company will provide a copy of
this Agreement to prospective purchasers of Initial Securities identified to the
Company by the Initial Purchasers upon request. Notwithstanding the foregoing,
nothing in this Section 7 shall

                                       19

<PAGE>

be deemed to require the Company to register any of its securities pursuant to
the Exchange Act.

         8.  Miscellaneous.

         (a) Remedies. The Company acknowledges and agrees that any failure by
the Company to comply with its obligations under Section 1 and 2 hereof may
result in material irreparable injury to the Initial Purchasers or the Holders
for which there is no adequate remedy at law, that it will not be possible to
measure damages for such injuries precisely and that, in the event of any such
failure, the Initial Purchasers or any Holder may obtain such relief as may be
required to specifically enforce the Company's obligations under Sections 1 and
2 hereof. The Company further agrees to waive the defense in any action for
specific performance that a remedy at law would be adequate.

         (b) No Inconsistent Agreements. The Company will not on or after the
date of this Agreement enter into any agreement with respect to its securities
that could impair the rights granted to the Holders in this Agreement or
otherwise conflicts with the provisions hereof. The rights granted to the
Holders hereunder do not in any way conflict with the rights granted to the
holders of the Company's securities under any agreement in effect on the date
hereof.

         (c) Amendments and Waivers. The provisions of this Agreement may not be
amended, modified or supplemented, and waivers or consents to departures from
the provisions hereof may not be given, except by the Company and the written
consent of the Holders of a majority in principal amount of the Securities
affected by such amendment, modification, supplement, waiver or consents.

         (d) Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, first-class mail,
facsimile transmission, or air courier which guarantees overnight delivery:

             (1)  if to a Holder of the Securities, at the most current address
given by such Holder to the Company.

             (2)  if to the Initial Purchasers;

                  Credit Suisse First Boston Corporation
                  Eleven Madison Avenue
                  New York, NY 10010-3629
                  Fax No.:  (212) 325-8278
                  Attention:  Transactions Advisory Group

         with a copy to:

                                       20

<PAGE>

                    Cahill Gordon & Reindel
                    80 Pine Street
                    New York, NY 10005
                    Fax No.: (212) 269-5420
                    Attention: John A. Tripodoro, Esq.

               (3)  if to the Company, at its address as follows:

                    Compass Minerals Group, Inc.
                    8300 College Boulevard
                    Overland Park, KS 66210
                    Fax No.: (913) 338-7932
                    Attention: Chief Financial Officer

                                       21

<PAGE>

         with a copy to:

                    Latham & Watkins
                    885 Third Avenue
                    New York, NY 10022
                    Fax No.:  (212) 751-4864

                    Attention:  Gregory Ezring, Esq.

             All such notices and communications shall be deemed to have been
         duly given: at the time delivered by hand, if personally delivered;
         three business days after being deposited in the mail, postage prepaid,
         if mailed; when receipt is acknowledged by recipient's facsimile
         machine operator, if sent by facsimile transmission; and on the day
         delivered, if sent by overnight air courier guaranteeing next day
         delivery.

         (e) Third Party Beneficiaries. The Holders shall be third party
beneficiaries to the agreements made hereunder between the Company, on the one
hand, and the Initial Purchasers, on the other hand, and shall have the right to
enforce such agreements directly to the extent they may deem such enforcement
necessary or advisable to protect their rights or the rights of Holders
hereunder.

         (f) Successors and Assigns. This Agreement shall be binding upon the
Company and its successors and assigns. A Holder of Securities takes such
Securities subject to the terms of this Agreement.

         (g) Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

         (h) Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

         (i) Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

         (j) Severability. If any one or more of the provisions contained
herein, or the application thereof in any circumstance, is held invalid, illegal
or unenforceable, the validity, legality and enforceability of any such
provision in every other respect and of the remaining provisions contained
herein shall not be affected or impaired thereby.

         (k) Securities Held by the Company. Whenever the consent or approval of
Holders of a specified percentage of principal amount of Securities is required
hereunder, Securities

                                       22

<PAGE>

held by the Company or its affiliates (other than subsequent Holders of
Securities if such subsequent Holders are deemed to be affiliates solely by
reason of their holdings of such Securities) shall not be counted in determining
whether such consent or approval was given by the Holders of such required
percentage.

         By the execution and delivery of this Agreement, the Issuer and each of
the Guarantors submits to the non-exclusive jurisdiction of the Federal and
state courts in the Borough of Manhattan in The City of New York in any suit or
proceeding arising out of or relating to this Agreement or the transactions
contemplated hereby.

         If the foregoing is in accordance with your understanding of our
agreement, please sign and return to the Issuer a counterpart hereof, whereupon
this instrument, along with all counterparts, will become a binding agreement
among the several Initial Purchasers, the Issuer and the Guarantors in
accordance with its terms.

                                                 Very truly yours,

                                                 COMPASS MINERALS GROUP, INC.


                                                 by ____________________________
                                                    Name:
                                                    Title:

                                                 CAREY SALT COMPANY
                                                 GREAT SALT LAKE MINERALS
                                                    CORPORATION
                                                 GSL CORPORATION
                                                 NAMSCO INC.
                                                 NORTH AMERICAN SALT COMPANY

                                                 by ____________________________
                                                    Name:
                                                    Title:

                                       23

<PAGE>

The foregoing Registration
Rights Agreement is hereby confirmed
and accepted as of the date first
above written.

CREDIT SUISSE FIRST BOSTON CORPORATION
J.P. MORGAN SECURITIES INC.
DEUTSCHE BANK SECURITIES INC.
CREDIT LYONNAIS SECURITIES (USA) INC.


By: CREDIT SUISSE FIRST BOSTON CORPORATION

by  ___________________________________________
    Name:
    Title:

                                       24

<PAGE>

                                                                         ANNEX A

         Each broker-dealer that receives Exchange Securities for its own
account pursuant to the Exchange Offer must acknowledge that it will deliver a
prospectus in connection with any resale of such Exchange Securities. The Letter
of Transmittal states that by so acknowledging and by delivering a prospectus, a
broker-dealer will not be deemed to admit that it is an "underwriter" within the
meaning of the Securities Act. This Prospectus, as it may be amended or
supplemented from time to time, may be used by a broker-dealer in connection
with resales of Exchange Securities received in exchange for Initial Securities
where such Initial Securities were acquired by such broker-dealer as a result of
market-making activities or other trading activities. The Company has agreed
that, for a period of 180 days after the Expiration Date (as defined herein), it
will make this Prospectus available to any broker-dealer for use in connection
with any such resale. See "Plan of Distribution."


<PAGE>

                                                                         ANNEX B

         Each broker-dealer that receives Exchange Securities for its own
account in exchange for Initial Securities, where such Initial Securities were
acquired by such broker-dealer as a result of market-making activities or other
trading activities, must acknowledge that it will deliver a prospectus in
connection with any resale of such Exchange Securities. See "Plan of
Distribution."



<PAGE>

                                                                         ANNEX C

                              PLAN OF DISTRIBUTION

         Each broker-dealer that receives Exchange Securities for its own
account pursuant to the Exchange Offer must acknowledge that it will deliver a
prospectus in connection with any resale of such Exchange Securities. This
Prospectus, as it may be amended or supplemented from time to time, may be used
by a broker-dealer in connection with resales of Exchange Securities received in
exchange for Initial Securities where such Initial Securities were acquired as a
result of market-making activities or other trading activities. The Company has
agreed that, for a period of 180 days after the Expiration Date, it will make
this prospectus, as amended or supplemented, available to any broker-dealer for
use in connection with any such resale. In addition, until,             200[_],
all dealers effecting transactions in the Exchange Securities may be required to
deliver a prospectus./1/

         The Company will not receive any proceeds from any sale of Exchange
Securities by broker-dealers. Exchange Securities received by broker-dealers for
their own account pursuant to the Exchange Offer may be sold from time to time
in one or more transactions in the over-the-counter market, in negotiated
transactions, through the writing of options on the Exchange Securities or a
combination of such methods of resale, at market prices prevailing at the time
of resale, at prices related to such prevailing market prices or negotiated
prices. Any such resale may be made directly to purchasers or to or through
brokers or dealers who may receive compensation in the form of commissions or
concessions from any such broker-dealer or the purchasers of any such Exchange
Securities. Any broker-dealer that resells Exchange Securities that were
received by it for its own account pursuant to the Exchange Offer and any broker
or dealer that participates in a distribution of such Exchange Securities may be
deemed to be an "underwriter" within the meaning of the Securities Act and any
profit on any such resale of Exchange Securities and any commission or
concessions received by any such persons may be deemed to be underwriting
compensation under the Securities Act. The Letter of Transmittal states that, by
acknowledging that it will deliver and by delivering a prospectus, a
broker-dealer will not be deemed to admit that it is an "underwriter" within the
meaning of the Securities Act.

         For a period of 180 days after the Expiration Date the Company will
promptly send additional copies of this Prospectus and any amendment or
supplement to this Prospectus to

_________________
/1/      In addition, the legend required by Item 502(b) of Regulation S-K will
         appear on the back cover page of the Exchange Offer prospectus.

<PAGE>

any broker-dealer that requests such documents in the Letter of Transmittal. The
Company has agreed to pay all expenses incident to the Exchange Offer (including
the expenses of one counsel for the Holders of the Securities) other than
commissions or concessions of any brokers or dealers and will indemnify the
Holders of the Securities (including any broker-dealers) against certain
liabilities, including liabilities under the Securities Act.


                                        2

<PAGE>

                                                                         ANNEX D

[_]  CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE 10 ADDITIONAL
     COPIES OF THE PROSPECTUS AND 10 COPIES OF ANY AMENDMENTS OR SUPPLEMENTS
     THERETO.

           Name:    _______________________________________
           Address: _______________________________________

If the undersigned is not a broker-dealer, the undersigned represents that it is
not engaged in, and does not intend to engage in, a distribution of Exchange
Securities. If the undersigned is a broker-dealer that will receive Exchange
Securities for its own account in exchange for Initial Securities that were
acquired as a result of market-making activities or other trading activities, it
acknowledges that it will deliver a prospectus in connection with any resale of
such Exchange Securities; however, by so acknowledging and by delivering a
prospectus, the undersigned will not be deemed to admit that it is an
"underwriter" within the meaning of the Securities Act.