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                      FIRST AMENDMENT TO PURCHASE AGREEMENT


     THIS FIRST AMENDMENT TO PURCHASE AGREEMENT (the "Amendment"), is made as of
January 15, 1998,  by and between ICG  HOLDINGS,  INC.,  a Colorado  corporation
("Seller"),  and TRINET  ESSENTIAL  FACILITIES  X, INC., a Maryland  corporation
("Buyer"), with reference to the following facts:

     A. Seller and Buyer entered into that certain Purchase Agreement,  dated as
of December 9, 1997 (the "Agreement"),  with respect to the purchase and sale of
the Property.  Each  capitalized  term used in this  Amendment,  but not defined
herein, shall have the meaning ascribed to it in the Agreement.

     B. Buyer and  Seller  have  agreed  that Buyer  shall  waive the  condition
precedent  to the Closing that the Project has been  Substantially  Completed by
the Closing Date, as set forth in Section  8.2(d) of the  Agreement,  as long as
one  hundred  thirty  percent  (130%) of the Unpaid  Project  Costs shall not be
disbursed  to Seller  at  Closing,  but is held in escrow to pay for the  Unpaid
Project Costs pursuant to the terms and provisions contained herein.

     C. Because the actual amount of Buyer's  out-of-pocket  costs in connection
with the Purchase Agreement and the transactions contemplated thereby, the Lease
and the  Project,  for which  Seller is  required to  reimburse  Buyer up to two
hundred fifty  thousand  dollars  ($250,000)  pursuant to Section  9.3(b) of the
Purchase  Agreement,  will not be determined  by Closing,  Buyer and Seller have
agreed  that two  hundred  eighteen  thousand  seven  hundred  ninety-seven  and
twenty-five  hundredths dollars ($218,797.25) of the Purchase Price shall not be
disbursed to Seller at Closing,  but shall be held in escrow to satisfy Seller's
obligation.

     D. Seller and Buyer desire to enter into this Amendment to modify the terms
of the Agreement, all as set forth hereinbelow.

     NOW, THEREFORE, the parties agree as follows:

     1. Holdback Escrow.  The Agreement is hereby amended by adding new Sections
2.3 through 2.5 thereto, which read in their entirety as follows:

          "2.3 Funds for Unpaid Project Costs Held in Escrow.

          "(a) Escrow Account-A. Buyer and Seller acknowledge that there will be
     Unpaid  Project Costs after the Closing Date. In order to assure Buyer that
     such Unpaid Project Costs will be paid promptly as they become due,  Seller
     and Buyer agree that,  upon and subject to the terms and conditions of this
     section 2.3 and an escrow  agreement  (the "Escrow  Agreement") in the form
     attached  hereto as Exhibit S, at the Closing,  one hundred  thirty percent
     (130%) of the Unpaid  Project Costs shall not be then  disbursed to Seller,
     and  shall be held in escrow by the  Escrow  Holder in an  interest-bearing
     escrow account ("Escrow Account-A"), pursuant to the Escrow Agreement. Such
     escrowed  funds are referred to herein as "Escrow  Amount-A".  All interest
     earned on Escrow Amount-A shall be paid to Seller. Escrow Amount-A shall be
     held and disbursed in accordance with the terms of this section 2.3 and the
     Escrow Agreement.
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          "(b) Completion of Unfinished Work. Seller shall promptly complete all
     Unfinished  Work; in any event,  all Unfinished  Work shall be completed by
     Seller no later  than by June 30,  1998.  If Seller has not  completed  the
     Unfinished  Work by June 30, 1998,  Buyer may complete the Unfinished  Work
     and receive disbursements from Escrow Account-A upon Buyer's instruction to
     the  Escrow  Agent  to pay  for  the  costs  incurred  in  completing  such
     Unfinished  Work. If at any time Escrow  Amount-A is  insufficient to cover
     such costs incurred by Buyer to complete the Unfinished Work,  Seller shall
     promptly pay Buyer for such costs upon demand by Buyer,  as additional rent
     under the Lease.  Seller's  failure to pay such additional costs within ten
     (10) days after  demand  shall  constitute  an Event of  Default  under the
     Lease.

          "(c) Disbursements to Seller from Escrow Account-A.

          (i) Substantial Completion. From time to time, whenever Buyer receives
     evidence from Seller that Seller has paid for any  Unfinished  Work (in the
     form of one or more  invoices  together  with such lien  releases  or other
     evidence  of  payment  as Buyer  may  reasonably  require)  which  has been
     completed and is in place (as evidenced by an  architect's  certificate  or
     such other  evidence  as Buyer may  reasonably  require),  Buyer and Seller
     shall  instruct  the  Escrow  Holder  to  disburse  to Seller  from  Escrow
     Account-A  the amount paid by Seller for such  Unfinished  Work;  provided,
     however, that no disbursement from Escrow Account-A shall exceed the amount
     of the then remaining Escrow Amount-A.

          (ii) Punch-list  Items.  Upon satisfaction of the conditions set forth
     in Sections  7.5(i)(1)  through  7.5(i)(4)  and  7.5(i)(6)  (i.e.  once the
     Project is  Substantially  Completed),  Buyer and Seller shall instruct the
     Escrow Holder to disburse to Seller an amount equal to the remaining Escrow
     Amount-A less the amount  required to be held in escrow pursuant to Section
     7.5(j).  Buyer  and  Seller  shall  instruct  the  Escrow  Holder  to  make
     disbursements  to Seller from Escrow  Account-A  amounts  paid by Seller to
     complete the Punch-list Items pursuant to Section 2.3(c)(i).
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          "(d) Termination of Escrow Agreement.  Buyer and Seller shall instruct
     the Escrow  Holder  that  Escrow  Account-A  shall be closed and the Escrow
     Agreement  shall  terminate  with  respect  to  Escrow  Account-A  and  any
     remaining  amounts  of Escrow  Amount-A  shall be paid to  Seller  upon the
     earlier to occur of the  following:  (i) all sums have been  disbursed from
     Escrow  Account-A  in  accordance  with this section 2.3; or (ii) Buyer has
     received  adequate  evidence  from  Seller  (in the form of an  architect's
     certificate or such other  evidence as Buyer may  reasonably  require) that
     the Punch-list Items have been completed in their entirety.

          "2.4 Funds for Out-of-Pocket Costs Held in Escrow.

          "(a) Escrow  Account-B.  Buyer and Seller  acknowledge that, after the
     Closing Date, there will be out-of-pocket costs which have been incurred by
     Buyer prior to the  Closing  Date and which will be incurred by Buyer after
     the  Closing  Date  that are  required  to be  reimbursed,  but will not be
     reimbursed  by the  Closing  Date,  by Seller  pursuant  to Section  9.3(b)
     ("Out-of-Pocket  Costs").  In order to assure Buyer that such Out-of-Pocket
     Costs will be paid  promptly  as they  become  due,  Seller and Buyer agree
     that,  upon and subject to the terms and conditions of this section 2.4 and
     the Escrow Agreement,  at the Closing,  two hundred eighteen thousand seven
     hundred  ninety-seven and twenty-five  hundredths dollars  ($218,797.25) of
     the Purchase Price shall not be then disbursed to Seller, and shall be held
     in  escrow  by the  Escrow  Holder in an  interest-bearing  escrow  account
     ("Escrow Account-B"), pursuant to the Escrow Agreement. Such escrowed funds
     are referred to herein as "Escrow Amount-B".  All interest earned on Escrow
     Amount-B  shall  be paid to  Seller.  Escrow  Amount-B  shall  be held  and
     disbursed in  accordance  with the terms of this section 2.4 and the Escrow
     Agreement.

          "(b) Disbursements to Seller from Escrow Account-B. From time to time,
     whenever  Seller   receives   evidence  from  Buyer  that  Buyer  owes  any
     Out-of-Pocket  Costs  (in the form of one or more  invoices  or other  such
     evidence as Seller may reasonably require), Buyer and Seller shall instruct
     the Escrow  Holder to disburse to Buyer from  Escrow  Account-B  the amount
     paid by Buyer for such  Out-of-Pocket  Costs;  provided,  however,  that no
     disbursement  from  Escrow  Account-B  shall  exceed the amount of the then
     remaining Escrow Amount-B.

          "(c) Termination of Escrow Agreement.  Buyer and Seller shall instruct
     the Escrow  Holder  that  Escrow  Account-B  shall be closed and the Escrow
     Agreement  shall  terminate  with  respect  to  Escrow  Account-B  and  any
     remaining  amounts  of Escrow  Amount-B  shall be paid to  Seller  upon the
     earlier to occur of the  following:  (i) all sums have been  disbursed from
     Escrow  Account-B  in  accordance  with this section 2.4; or (ii) Buyer and
     Seller  have  agreed  in  writing  that  Seller  has  fully  satisfied  its
     obligation to reimburse Seller for the Out-of-Pocket Costs.
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          "2.5 Arbitration.

          "(a) Buyer and Seller agree that any dispute  respecting  their rights
     to Escrow Amount-A  and/or Escrow  Amount-B (the "Escrow  Amount") shall be
     determined  exclusively by final and binding arbitration in accordance with
     this  section  2.5.  In the  event  either  party  wishes  to  commence  an
     arbitration  proceeding  to resolve  any dispute  relating to the  parties'
     rights to the Escrow Amount, such arbitration shall be final and binding on
     Buyer and Seller,  shall be conducted in the County of Arapahoe,  Colorado,
     and shall be administered by and in accordance  with the  Comprehensive  or
     Streamlined  Arbitration  Rules and  Procedures of  J.A.M.S./Endispute,  as
     applicable,  or, if such rules no longer exist,  the then existing rules of
     practice  and  procedure  of  J.A.M.S./Endispute  (both  sets of rules  are
     collectively  referred  to  as  the  "Rules  of  J.A.M.S./Endispute").  The
     arbitrator  shall be a  retired  Colorado  or  federal  judge  selected  in
     accordance with the Rules of  J.A.M.S./Endispute.  The arbitrator and not a
     jury will decide the matter submitted to arbitration.

          "The arbitrator shall determine only the rights of Buyer and Seller to
     the Escrow Amount and no other issues.  Judgment upon any decision rendered
     by the  arbitrator  may be  entered by any state or  federal  court  having
     jurisdiction  thereof.  Subject to the final  sentence of this Section 2.5,
     the  arbitrator  shall have the power to award damages in  accordance  with
     this section 2.5 payable from Escrow  Account-A  and/or  Escrow  Account-B,
     whichever is applicable, and to order the disposition of the Escrow Amount,
     but shall not have the power to award any other  damages or grant any other
     relief,  and  shall  not have the  power  to vary  the  provisions  of this
     Agreement.

          "Discovery  in any  arbitration  shall  be  permitted  but it shall be
     limited to one deposition and the exchange of documents and witness lists.

          "Except as  otherwise  required  by law,  the  parties  agree that the
     arbitration  proceeding  will be  confidential;  all  conduct,  statements,
     promises,  offers,  views and  opinions,  oral or written,  made during the
     arbitration  by any party or a party's  agent,  employee or  attorney  will
     remain confidential and, where appropriate, will be considered work product
     and privileged;  and the existence and the results of the arbitration  will
     be maintained  by the parties and their  respective  agents,  employees and
     attorneys as confidential at all times.

          "In the event that J.A.M.S./Endispute is no longer in existence at the
     time that  arbitration  is  requested,  the dispute  shall be  submitted to
     arbitration in accordance with the rules and procedures of the successor to
     J.A.M.S./Endispute  or, if there is no such successor,  the matter shall be
     submitted  to  an  organization   which  consists  of  members  similar  to
     J.A.M.S./Endispute or its successor.
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          "The losing party shall bear all of its own and the prevailing party's
     costs and expenses  incurred in connection with the arbitration,  including
     the arbitrator's fees and costs."

     2. Survey. The Agreement is hereby further amended as follows:

          (a) Subparagraph (5) of Section 7.5(i) is hereby deleted.

          (b)  Section  7.5(g)  is  hereby  replaced  in its  entirety  with the
     following paragraph:

               "7.5(g)  Surveys.  If  Buyer  requests  upon  completion  of  the
          Project,  Seller  shall  deliver to Buyer,  at  Seller's  expense,  an
          as-built  survey  of  the  Real  Property   meeting  the  requirements
          described in Section 5.5 and showing no material encroachments,  bases
          for third-party  claims or violations of law or private  covenants not
          shown on the survey  delivered  pursuant  to Section  5.5 (the  "Final
          Survey").

     3. No Other Amendment; Conflict. Except as set forth in this Amendment, the
provisions of the  Agreement  shall remain in full force.  If the  provisions of
this  Amendment  conflict  with  the  provisions  of  the  Agreement,  then  the
provisions of this Amendment shall prevail.

     4.  Counterparts.  This  Amendment  may be signed in multiple  counterparts
which, when signed by all parties, shall constitute a binding agreement.

SELLER:                       ICG HOLDINGS, INC., a Colorado
                              corporation


                              By: /s/ James D. Grenfell
                                  --------------------------------
                                   James D. Grenfell

                                 Its: Executive Vice President
                                      and Chief Financial Officer


BUYER:                        TRINET ESSENTIAL FACILITIES X, INC.,
                              a Maryland corporation

                              By: /s/Gary P. Lyon
                                  --------------------------------
                                   Garry P. Lyon

                                 Its: Executive Vice President