<Page>
EXHIBIT 99.4
EIGHTH AMENDMENT TO COST SHARING NATIONAL
IRU AGREEMENT
THIS EIGHTH AMENDMENT TO COST SHARING NATIONAL IRU AGREEMENT
("Amendment") is made and entered into as of the ____ day of December 2000 (the
"Amendment Effective Date"), by and between LEVEL 3 COMMUNICATIONS, LLC, a
Delaware limited liability company ("Grantor") and MCLEODUSA INFORMATION
SERVICES, INC. (f/k/a Splitrock Services, Inc.), a Delaware corporation
("Grantee"). This Amendment modifies and amends that certain Cost Sharing
National IRU Agreement dated April 26, 1999 between Grantor and Grantee (the
"Agreement"). Capitalized terms used but not defined herein shall have the
meanings set forth in the Agreement.
RECITALS
A. The parties desire to amend the Intercity Route Schedule and the
Scheduled Completion Dates and fiber counts for certain Segments, subject to and
in accordance with the terms and provisions set forth in this Amendment.
B. The parties desire to amend the Acceptance Testing procedures of
the Grantee Fibers, subject to and in accordance with the terms and provisions
set forth in this Amendment.
C. The parties desire to amend the procedures for obtaining future
space in the Facilities, subject to and in accordance with the terms and
provisions set forth in this Amendment.
TERMS OF AMENDMENT
Accordingly, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, Grantor and Grantee hereby agree as follows:
ARTICLE 1
REVISION TO GRANTOR INTERCITY ROUTE SCHEDULES
1.01 The EXHIBIT "B" attached to the Agreement (Grantor Intercity Route
Schedule), as amended by the Second Amendment dated March 30, 2000 and the
Seventh Amendment dated September 25, 2000, is hereby deleted and is replaced by
the EXHIBIT "B" attached hereto (Grantor Intercity Route Schedule).
1.02 The EXHIBIT "A-1" attached to the Seventh Amendment, dated
September 25, 2000 (First Additional Intercity Fibers), is hereby deleted and is
replaced by the EXHIBIT "A-1" attached hereto (First Additional Intercity
Fibers).
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1.03 The EXHIBIT "A-2" attached to the Seventh Amendment dated
September 25, 2000 (Second Additional Intercity Fibers) is hereby deleted and is
replaced by the EXHIBIT "A-2" attached hereto (Second Additional Intercity
Fibers).
1.04 Section 1.02 of the Seventh Amendment is hereby deleted and is
replaced by the following Section 1.02:
"1.02 The number of Grantee Fibers in Segment 12b, which is that
portion of the Grantor System between Ft. Worth, Texas and Dallas,
Texas, is hereby ***. The parties recognize that Grantee has paid to
Grantor ***, which is the difference between the fees previously due
and payable for *** fibers and the amount due for the *** fibers. Said
amount shall be credited against *** Contributions that are owed by
Grantee to Grantor."
1.05 Section 2.02 of the Seventh Amendment is hereby deleted and is
replaced by the following Section 2.02:
"2.02 Grantee shall pay to Grantor an IRU Contribution for the
Additional Intercity Fibers on a per Segment basis in the amounts
specified in Exhibits "A-1" and "A-2." The IRU Contribution shall be
due from Grantee to Grantor with respect to the Additional Intercity
Fibers in each Segment as follows: (i) *** percent (***%) on the
Amendment Effective Date (which equates to ***), and (ii) *** percent
(***%) on the Acceptance Date of such Segment."
Grantee has already paid to Grantor *** toward twenty five percent (25%) of the
IRU Contribution.
ARTICLE 2
SEGMENT REVISIONS
2.01 The following Grantee Fibers from each of the following Segments are
hereby deleted from the Grantor System (the "First Deleted Fibers"):
<Table>
<Caption>
GRANTEE
ROUTE SEGMENT CITY PAIR ROUTE MILES FIBER COUNT TOTAL FIBER MILES
- --------------------------------------------------------------------------------------------------------------
19c Austin to Fort Worth 208.34 *** ***
7 Dallas to Houston 247.26 *** ***
12b Fort Worth to Dallas 30.05 *** ***
19b San Antonio to Austin 79.38 *** ***
19a San Antonio to Houston 217.14 *** ***
5c Dallas to Memphis 505.46 *** ***
11b Houston to New Orleans 364.92 *** ***
TOTAL ***
</Table>
*** In exchange for the deletion of the First Deleted Fibers, the following
Segment shall be added to the Grantor System, and Grantor shall deliver an IRU
in, and Grantee shall
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accept and pay for (in accordance with Section 2.03), an IRU in *** Grantee
Fibers within and along the following additional Segment:
<Table>
<Caption>
GRANTEE FIBER
ROUTE SEGMENT CITY PAIR ROUTE MILES COUNT TOTAL FIBER MILES
- -------------------------------------------------------------------------------------------------------
16 Sacramento to San Bernardino 472.15 *** ***
</Table>
2.02 The following Grantee Fibers from each of the following Segments are
hereby deleted from the Grantor System (the "Second Deleted Fibers"):
<Table>
<Caption>
GRANTEE FIBER
ROUTE SEGMENT CITY PAIR ROUTE MILES COUNT TOTAL FIBER MILES
- --------------------------------------------------------------------------------------------------------------
7 Dallas to Houston 247.26 *** ***
19a San Antonio to Houston 217.14 *** ***
5c Dallas to Memphis 505.46 *** ***
11b Houston to New Orleans 364.92 *** ***
12b Fort Worth to Dallas 30.05 *** ***
TOTAL ***
</Table>
*** In exchange for the deletion of the Second Deleted Fibers, Grantor shall
deliver an IRU in, and Grantee shall accept and pay for (in accordance with
Section 2.03), an IRU in the additional Grantee Fibers within and along the
following Segments:
<Table>
<Caption>
ESTIMATED ADDITIONAL TOTAL ESTIMATED FIBER
ROUTE SEGMENT CITY PAIR ROUTE MILES GRANTEE FIBERS MILES
- ---------------------------------------------------------------------------------------------------------
8 Los Angeles to San Diego 165 *** ***
12a San Diego to Phoenix 355 *** ***
12c Phoenix to Santa Teresa (El 417 *** ***
Paso)
TOTAL ***
</Table>
2.03 Grantee shall pay to Grantor an IRU Contribution for the new Segment
identified in Section 2.01 and the additional Grantee Fibers identified in
Section 2.02 on a *** basis. The IRU Contribution for the new Segment identified
in Section 2.01 shall be ***. The IRU Contribution for the additional Grantee
Fibers identified in Section 2.02 shall be ***. The remaining IRU Contribution
for *** shall be due and payable on ***. The remaining IRU Contribution for ***
shall be due and payable on ***. The IRU Contribution for *** shall be due from
Grantee to Grantor in each Segment as follows: *** percent (***%) on the
Amendment Effective Date (which equates to ***), and (ii) *** percent (***%) on
the Acceptance Date of such Segment.
2.04 The fibers located in the new Segment identified in Section 2.01 and
Section 2.02 and the additional fibers identified in Section 2.02 shall be
considered Grantee Fibers
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under the Agreement. The IRU with respect to such fibers shall commence as of
the IRU Effective Date for the relevant Segment.
2.05 The Parties recognize that Grantee has installed Facilities within the
space allocated to Grantee located in Grantor's Facilities ***. Grantee shall
remove all of its Facilities located within such space, abandon such space, and
restore the space to a condition suitable for another customer, in Grantor's
reasonable discretion, within thirty (30) days of the Amendment Effective Date.
Grantee shall continue to pay all applicable charges (including, without
limitation, the Facilities Contribution and the Utility Charge) for any space
occupied by Grantee until Grantee has removed its Facilities from such space.
ARTICLE 3
ACCEPTANCE TESTING SPECIFICATIONS
The EXHIBIT "I" attached to the Agreement (Acceptance Testing
Procedures and Standards) is hereby deleted and is replaced by the EXHIBIT "I"
attached hereto (Acceptance Testing Procedures and Standards).
ARTICLE 4
FACILITIES SPACE
Notwithstanding anything to the contrary contained in Section 7.03 of
the Agreement (as amended by the Second Amendment and the Seventh Amendment), in
the event that Grantee determines after the Amendment Effective Date that it
will ***, then Grantor will, *** . Grantee shall pay Grantor a one-time fee of
*** for *** ordered on or before ***. For orders placed after ***, Grantee shall
pay Grantor the then current rate for ***.
ARTICLE 5
REVISION TO GRANTOR SYSTEM MAP
The EXHIBIT "A" attached to the Agreement (Grantor System Map) is
hereby deleted and is replaced by the EXHIBIT "A" attached hereto (Grantor
System Map).
ARTICLE 6
GRANTEE SPACE REQUIREMENTS
The EXHIBIT "K" attached to the Agreement (Grantee Space
Requirements), as further amended by the Seventh Amendment, is hereby deleted
and is replaced by the EXHIBIT "K" attached hereto (Grantee Space Requirements).
ARTICLE 7
RATIFICATION
Except as amended by the First, Second, Third, Fourth, Fifth, Sixth,
Seventh and this Eighth Amendment, the original terms and provisions of the
Agreement shall continue in full force and effect and the Agreement, as amended
by the First, Second, Third, Fourth, Fifth, Sixth, Seventh and this Eighth
Amendment, is hereby ratified and confirmed.
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IN WITNESS WHEREOF, Grantor and Grantee have executed this Amendment
as of the date first written above.
LEVEL 3 COMMUNICATIONS, LLC MCLEODUSA INFORMATION SERVICES,
INC. (f/k/a Splitrock
Services, Inc.)
By: By:
----------------------------- ---------------------------
Title: Title:
----------------------------- ---------------------------
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EXHIBIT "A"
GRANTOR SYSTEM MAP
SPLITROCK
EXHIBIT "A" GRANTOR SYSTEM MAP
[MAP]
LEVEL(3)
COMMUNICATIONS
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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EXHIBIT "A-1"
FIRST ADDITIONAL INTERCITY FIBERS
SEGMENTS/CITY PAIRS
<Table>
<Caption>
FIRST ADDITIONAL IRU SCHEDULED
ESTUNATED ROUTE INTERCITY FIBERS ESTIMATED IRU COMPLETION
ROUTE SEGMENT CITY PAIRS MILES ORDERED FEE DATE
- -------------------------------------------------------------------------------------------------------------
NORTHWEST DISTRICT
4e Las Vegas to Ogden 476 *** *** ***
Salt Lake City to Ogden 35 *** *** ***
13a Sacramento to Portland 643 *** *** ***
13b Portland to Seattle 193 *** V ***
18a Seattle to Boise 550 V *** ***
18b Boise to Ogden 395 *** *** ***
Regional Total 2,292
N. CALIFORNIA DISTRICT
2a San Jose to San Francisco 45 *** *** ***
2b San Jose to San Luis Obispo 198 *** *** ***
2c San Luis Obispo to Los
Angeles 244 *** *** ***
2d San Francisco to Oakland 10 *** *** ***
2e Oakland to Sacramento 85 *** *** ***
Regional Total 582
PHOENIX DISTRICT
4a1 LA to San Bernardino 67 *** *** ***
4a2 San Bernardino to Las Vegas 229 *** *** ***
8 LA to San Diego 165 *** *** ***
LA to San Diego *** ***
12a San Diego to Phoenix 355 *** *** ***
12c Phoenix to Santa Teresa (El
Paso) 417 *** *** ***
Regional Total 1,233
DENVER DISTRICT
4b St. Louis to Chicago 299 *** *** ***
4c Kansas City to St. Louis 302 *** ***
4d Omaha to Kansas City 215 *** *** ***
4f Ogden to Denver 603 *** *** ***
4g Denver to Omaha 554 *** *** ***
12e Santa Teresa (El Paso) to
Stratford 471 *** *** ***
14a Denver to Stratford 358 *** *** ***
Regional Total 2,802
TEXAS DISTRICT
5c Dallas to Memphis 505 *** *** ***
5e Memphis to Nashville 251 *** *** ***
7 Dallas to Houston 247 *** *** ***
11b Houston to New Orleans 365 *** *** ***
11c1 New Orleans to Tallahassee 481 *** *** ***
12b Ft. Worth to Dallas 30 *** *** ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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<Table>
<Caption>
FIRST ADDITIONAL IRU SCHEDULED
ESTIMATED ROUTE INTERCITY FIBERS ESTIMATED IRU COMPLETION
ROUTE SEGMENT CITY PAIRS MILES ORDERED FEE DATE
- -------------------------------------------------------------------------------------------------------------
12d Stratford to Ft. Worth 424 *** *** ***
19a San Antonio to Houston 217 *** *** ***
19b San Antonio to Austin 79 *** *** ***
19c Austin to Ft. Worth 208 *** *** ***
Regional Total 2,807
SOUTHEAST DISTRICT
5d Louisville to Cincinnati 126 *** *** ***
5f Nashville to Louisville 230 *** *** ***
9b Atlanta to Charlotte 253 *** *** ***
9d Charlotte to Raleigh 200 *** *** ***
10a Atlanta to Jacksonville 350 *** *** ***
10b Orlando to Miami 252 *** *** ***
10c Jacksonville to Orlando 141 *** *** ***
11a Tampa to Miami 300 *** *** ***
11c2 Tallahassee to Tampa 244 *** *** ***
17 Nashville to Atlanta 381 *** *** ***
Regional Total 2,477
NORTHEAST DISTRICT
1a Newark to New York 16 *** *** ***
1b Princeton to Newark 42 *** *** ***
1c Philadelphia to Princeton 61 *** *** ***
1d Wilmington to Philadelphia 37 *** *** ***
6a New York to Stamford 45 *** *** ***
6b Providence to Boston 49 *** *** ***
6d Stamford to Hartford 96 *** *** ***
6e Hartford to Providence 81 *** *** ***
15a Cleveland to Buffalo 192 *** *** ***
15b Albany to Boston 175 *** *** ***
Regional Total 794
NEW YORK DISTRICT
1e Baltimore to Wilmington 79 *** *** ***
1f Washington DC to Baltimore 78 *** *** ***
3a Chicago to Detroit 324 *** *** ***
3b Pittsburgh to Washington DC 272 *** *** ***
3c Detroit to Cleveland 190 *** *** ***
3d Cleveland to Pittsburgh 162 *** *** ***
5a Chicago to Indianapolis 239 *** *** ***
5b Indianapolis to Cincinnati 114 *** *** ***
9a Richmond to Washington DC 120 *** *** ***
9c Raleigh to Richmond 175 *** *** ***
Regional Total 1,753
E. CANADA DISTRICT
15c Toronto to Buffalo 111 *** *** ***
15d Montreal to Albany 240 *** *** ***
15e Toronto to Ottawa 260 *** *** ***
15f Ottawa to Montreal 103 *** *** ***
Regional Total 714
Network Total 15,454 ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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<Page>
<Table>
<Caption>
FIRST ADDITIONAL IRU SCHEDULED
ESTUNATED ROUTE INTERCITY FIBERS ESTIMATED IRU COMPLETION
ROUTE SEGMENT CITY PAIRS MILES ORDERED FEE DATE
- -------------------------------------------------------------------------------------------------------------
</Table>
The Scheduled Completion Date shall be *** listed as the IRU Scheduled
Completion Date. The IRU Contribution for the excess fiber miles described in
Section 2.03 has not been incorporated in this Exhibit.
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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<Page>
EXHIBIT "A-2"
SECOND ADDITIONAL INTERCITY FIBERS
SEGMENTS/CITY PAIRS
<Table>
<Caption>
SECOND
ADDITIONAL
ESTIMATED ROUTE INTERCITY FIBERS ESTIMATED IRU IRU SCHEDULED
ROUTE SEGMENT CITY PAIRS MILES ORDERED FEE COMPLETION DATE
- -----------------------------------------------------------------------------------------------------------------
NORTHWEST DISTRICT
4e Las Vegas to Ogden 476 *** *** ***
Salt Lake City to Ogden 35 *** *** ***
13a Sacramento to Portland 643 *** *** ***
13b Portland to Seattle 193 *** *** ***
18a Seattle to Boise 550 *** *** ***
18b Boise to Ogden 395 *** *** ***
Regional Total 2,292
N. CALIFORNIA DISTRICT
2a San Jose to San Francisco 45 *** *** ***
2b San Jose to San Luis Obispo 198 *** *** ***
2c San Luis Obispo to Los
Angeles 244 *** *** ***
2d San Francisco to Oakland 10 *** *** ***
2e Oakland to Sacramento 85 *** *** ***
Regional Total 582
PHOENIX DISTRICT
4a1 LA to San Bernardino 67 *** *** ***
4a2 San Bernardino to Las Vegas 229 *** *** ***
8 LA to San Diego 165 *** *** ***
12a San Diego to Phoenix 355 *** *** ***
San Diego to Phoenix *** *** ***
12c Phoenix to Santa Teresa (El
Paso) 417 *** *** ***
Phoenix to Santa Teresa (El Paso) *** *** ***
Regional Total 1,233
DENVER DISTRICT
4b St. Louis to Chicago 299 *** *** ***
4c Kansas City to St. Louis 302 *** *** ***
4d Omaha to Kansas City 215 *** *** ***
4f Ogden to Denver 603 *** *** ***
4g Denver to Omaha 554 *** *** ***
12e Santa Teresa (El Paso) to
Stratford 471 *** *** ***
14a Denver to Stratford 358 *** *** ***
Regional Total 2,802
TEXAS DISTRICT
5c Dallas to Memphis 505 *** *** ***
5e Memphis to Nashville 251 *** *** ***
7 Dallas to Houston 247 *** *** ***
11b Houston to New Orleans 365 *** *** ***
11c1 New Orleans to Tallahassee 481 *** *** ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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<Page>
<Table>
<Caption>
SECOND
ADDITIONAL
ESTIMATED ROUTE INTERCITY FIBERS ESTIMATED IRU IRU SCHEDULED
ROUTE SEGMENT CITY PAIRS MILES ORDERED FEE COMPLETION DATE
- -----------------------------------------------------------------------------------------------------------------
12b Ft. Worth to Dallas 30 *** *** ***
12d Stratford to Ft. Worth 424 *** *** ***
19a San Antonio to Houston 217 *** *** ***
19b San Antonio to Austin 79 *** *** ***
19c Austin to Ft. Worth 208 *** *** ***
Regional Total 2,807
SOUTHEAST DISTRICT
5d Louisville to Cincinnati 126 *** *** ***
5f Nashville to Louisville 230 *** *** ***
9b Atlanta to Charlotte 253 *** *** ***
9d Charlotte to Raleigh 200 *** *** ***
10a Atlanta to Jacksonville 350 *** *** ***
10b Orlando to Miami 252 *** *** ***
10c Jacksonville to Orlando 141 *** *** ***
11a Tampa to Miami 300 *** *** ***
11c2 Tallahassee to Tampa 244 *** *** ***
17 Nashville to Atlanta 381 *** *** ***
Regional Total 2,477
NORTHEAST DISTRICT
1a Newark to New York 16 *** *** ***
1b Princeton to Newark 42 *** *** ***
1c Philadelphia to Princeton 61 *** *** ***
1d Wilmington to Philadelphia 37 *** *** ***
6a New York to Stamford 45 *** *** ***
6b Providence to Boston 49 *** *** ***
6d Stamford to Hartford 96 *** *** ***
6e Hartford to Providence 81 *** *** ***
15a Cleveland to Buffalo 192 *** *** ***
15b Albany to Boston 175 *** *** ***
Regional Total 794
NEW YORK DISTRICT
1e Baltimore to Wilmington 79 *** *** ***
1f Washington DC to Baltimore 78 *** *** ***
3a Chicago to Detroit 324 *** *** ***
3b Pittsburgh to Washington DC 272 *** *** ***
3c Detroit to Cleveland 190 *** *** ***
3d Cleveland to Pittsburgh 162 *** *** ***
5a Chicago to Indianapolis 239 *** *** ***
5b Indianapolis to Cincinnati 114 *** *** ***
9a Richmond to Washington DC 120 *** *** ***
9c Raleigh to Richmond 175 *** *** ***
Regional Total 1,753
E. CANADA DISTRICT
15c Toronto to Buffalo 111 *** *** ***
15d Montreal to Albany 240 *** *** ***
15e Toronto to Ottawa 260 *** *** ***
15f Ottawa to Montreal 103 *** *** ***
Regional Total 714
</Table>
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<Page>
<Table>
<Caption>
SECOND
ADDITIONAL
ESTIMATED ROUTE INTERCITY FIBERS ESTIMATED IRU IRU SCHEDULED
ROUTE SEGMENT CITY PAIRS MILES ORDERED FEE COMPLETION DATE
- -----------------------------------------------------------------------------------------------------------------
Network Total 15,454 ***
</Table>
The Scheduled Completion Date shall be the last day of the month listed as the
IRU Scheduled Completion Date.
The IRU Contribution for the excess fiber miles described in Section 2.03 has
not been incorporated in this Exhibit.
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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EXHIBIT "B"
SEGMENTS/CITY PAIRS
GRANTOR INTERCITY ROUTE SCHEDULE
<Table>
<Caption>
ROUTE ESTIMATED PRICE PER ESTIMATED IRU IRU SCHEDULED
SEGMENT CITY PAIRS ROUTE MILES FIBER COUNT MILE FEE(1) COMPLETION DATE
- ----------------------------------------------------------------------------------------------------------------------------
NORTHWEST DISTRICT
4e Las Vegas to Ogden 476 *** *** *** ***
Salt Lake City to Ogden(2) 35 *** *** *** ***
13a Sacramento to Portland 643 *** *** *** ***
13b Portland to Seattle 193 *** *** *** ***
18a Seattle to Boise 550 *** *** *** ***
18b Boise to Ogden 395 *** *** *** ***
REGIONAL TOTAL 2,292 ***
N.CALIFORNIA DISTRICT
2a San Jose to San Francisco 45 *** *** *** ***
2b San Jose to San Luis Obispo 198 *** *** *** ***
2c San Luis Obispo to Los Angeles 244 *** *** *** ***
2d San Francisco to Oakland 10 *** *** *** ***
2e Oakland to Sacramento 85 *** *** *** ***
16 Sacramento to San Bernardino 472 *** ***
16 Sacramento to San Bernardino N/A *** ***
REGIONAL TOTAL 1,054 ***
PHOENIX DISTRICT
4a1 LA to San Bernardino 67 *** *** *** ***
4a2 San Bernardino to Las Vegas 229 *** *** *** ***
8 LA to San Diego(3) 165 *** *** *** ***
12a San Diego to Phoenix 355 *** *** *** ***
12c Phoenix to Santa Teresa (El Paso) 417 *** *** *** ***
REGIONAL TOTAL 1,233 ***
DENVER DISTRICT
4b St. Louis to Chicago 299 *** *** *** ***
4c Kansas City to St. Louis 302 *** *** *** ***
4d Omaha to Kansas City 215 *** *** *** ***
4f Ogden to Denver 603 *** *** *** ***
4g Denver to Omaha 554 *** *** *** ***
12e Santa Teresa (El Paso) to Stratford 471 *** *** *** ***
14a Denver to Stratford 358 *** *** *** ***
REGIONAL TOTAL 2,802 ***
</Table>
- ----------
(1) Estimated IRU Contribution; ***
(2) This segment only broken out due to ***
(3) In the original IRU, this segment is broken down into LA to Orange and
Orange to San Diego
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<Table>
TEXAS DISTRICT
5c Dallas to Memphis 505 *** *** *** ***
5e Memphis to Nashville 251 *** *** *** ***
7 Dallas to Houston 247 *** *** *** ***
11b Houston to New Orleans 365 *** *** *** ***
11c1 New Orleans to Tallahassee(4) 481 *** *** *** ***
12b Ft. Worth to Dallas 30 *** *** *** ***
12d Stratford to Ft. Worth 424 *** *** *** ***
19a San Antonio to Houston 217 *** *** *** ***
19b San Antonio to Austin 79 *** *** *** ***
19c Austin to Ft. Worth 208 *** *** *** ***
REGIONAL TOTAL 2807 ***
SOUTHEAST DISTRICT
5d Louisville to Cincinnati 126 *** *** *** ***
5f Nashville to Louisville 230 *** *** *** ***
9b Atlanta to Charlotte 253 *** *** *** ***
9d Charlotte to Raleigh 200 *** *** *** ***
10a Atlanta to Jacksonville 350 *** *** *** ***
10b Orlando to Miami 252 *** *** *** ***
10c Jacksonville to Orlando 141 *** *** *** ***
11a Tampa to Miami 300 *** *** *** ***
11c2 Tallahassee to Tampa(5) 244 *** *** *** ***
17 Nashville to Atlanta 381 *** *** *** ***
REGIONAL TOTAL 2477 ***
NORTHWEST DISTRICT
1a Newark to New York 16 *** *** *** ***
1b Princeton to Newark 42 *** *** *** ***
1c Philadelphia to Princeton 61 *** *** *** ***
1d Wilmington to Philadelphia 37 *** *** *** ***
6a New York to Stamford(6) 45 *** *** *** ***
6b Providence to Boston 49 *** *** *** ***
6d Stamford to Hartford 96 *** *** *** ***
6e Hartford to Providence 81 *** *** *** ***
15a Cleveland to Buffalo 192 *** *** *** ***
15b Albany to Boston 175 *** *** *** ***
REGIONAL TOTAL 794 ***
</Table>
- ----------
(4) In the original IRU, this segment is combined with Tallahassee to Tampa to
form N.O. to Tampa
(5) In the original IRU, this segment is combined with New Orleans to
Tallahassee to form N.O. to Tampa
(6) In the original IRU, this segment is broken down into New York to While
Plains and White Plains to Stamford
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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<Table>
NEW YORK DISTRICT
1e Baltimore to Wilmington 79 *** *** *** ***
1f Washington DC to Baltimore 78 *** *** *** ***
3a Chicago to Detroit 324 *** *** *** ***
3b Pittsburgh to Washington DC 272 *** *** *** ***
3c Detroit to Cleveland 190 *** *** *** ***
3d Cleveland to Pittsburgh 162 *** *** *** ***
5a Chicago to Indianapolis 239 *** *** *** ***
5b Indianapolis to Cincinnati 114 *** *** *** ***
9a Richmond to Washington DC 120 *** *** *** ***
9c Raleigh to Richmond 175 *** *** *** ***
REGIONAL TOTAL 1753 ***
E. CANADA DISTRICT
15c Toronto to Buffalo 111 *** *** *** ***
15d Montreal to Albany 240 *** *** *** ***
15e Toronto to Ottawa 260 *** *** *** ***
15f Ottawa to Montreal 103 *** *** *** ***
REGIONAL TOTAL 714 ***
NATIONWIDE TOTAL =15,926
</Table>
The Scheduled Completion Date shall be the last day of the month listed as the
IRU Scheduled Completion Date.
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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EXHIBIT "I"
ACCEPTANCE TESTING PROCEDURES AND STANDARDS
After Grantor has completed end-to-end connectivity on the fibers,
bi-directional span testing with an Optical Time Domain Reflectometer ("OTDR")
will be done. Once the pigtails have been spliced, loss measurements will be
recorded using an industry-accepted laser source and a power meter. OTDR traces
will be taken and splice loss measurements will be recorded. Grantor will store
OTDR traces on data sheets. Copies of all data sheets will be available to
Grantee.
The power loss measurements shall be made at 1550 nm, and performed
bi-directionally.
OTDR traces shall be taken in both directions at 1550 nm.
Guaranteed span loss shall include loss from fiber attenuation, splices and
connectors coupling cable to the Grantor-designated optical termination panel.
The loss shall not include the fiber/cable and connectors from the
Grantor-designated optical termination panel to Grantee's colocation space.
Average loss per span shall be calculated on a fiber length basis only. The
average loss per span shall not exceed 0.25 dB/km.
The fibers shall be terminated to the Grantor-designated optical termination
panel with SC-PC connectors, unless another type of connector is specified.
Pigtails and jumpers shall be manufactured with standard single mode fiber or
equivalent.
Testing for Segments for which the Segment End Point is other than a Grantor
point of presence shall be performed in a coordinated fashion, so that Grantee
shall connect and test the fiber owned by it in conjunction with Grantor's
testing of the Grantee Fibers. In the event that the entire tested portion does
not satisfy the testing criteria set forth herein, Grantee and Grantor shall
work together in good faith to pinpoint the cause of the problem and each party
shall be responsible for the timely performance of such repairs on the fibers
owned by it (so that Grantor shall only be responsible for repairs needed to
bring the Grantee Fibers into compliance with this Exhibit). Grantor may (in the
event of a dispute respecting testing and acceptance of the Grantee Fibers
within any such Segment) arrange to have the Grantee Fibers tested only to the
Segment End Point and, if such Grantee Fibers meet the testing criteria set
forth herein, Grantee shall be obligated to accept and pay for such Grantee
Fibers (notwithstanding the fact that the fibers connected to Grantor's point of
presence may not be functioning properly).
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
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EXHIBIT "K"
GRANTEE SPACE REQUIREMENTS
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
LAS VEGAS TO OGDEN
*** Coyote Springs *** ***
*** Monument Canyon *** ***
*** Yale Crossing *** ***
*** Millford, UT *** ***
*** Delta (Oasis) *** ***
*** Lofgreen *** ***
*** Ogden *** ***
SACRAMENTO TO PORTLAND
*** Colusa (Fagan) *** ***
*** Corning (Tehama) (RedBluff) *** ***
*** Palo Cedro (Oak Run) *** ***
*** Burney (Hors Four Corners) *** ***
*** Tionesta (Homestead)(Copic) *** ***
*** Modoc Pt. *** ***
*** Chemult (Paunina) *** ***
*** Oakridge (Westfir) *** ***
*** Eugene (Swain) *** ***
*** Salem *** ***
PORTLAND TO SEATTLE
*** Ostrander *** ***
*** Olympia *** ***
SEATTLE TO BOISE
*** North Bend (Issaquah) *** ***
*** Cle Elum (Easton) *** ***
*** Fruitvale (Cottonwoods) *** ***
*** Prosser (Byron) *** ***
*** Rieth (Stanfield) *** ***
*** LaGrande (Pelican) Creek *** ***
*** Durkee (Oxman) (Ebell Creek) *** ***
*** Ontario *** ***
BOISE TO OGDEN
*** Boise *** ***
*** Reverse *** ***
*** Gooding *** ***
*** Rupert *** ***
*** Bridge *** ***
*** Howelll *** ***
SAN JOSE TO SAN FRANCISCO
SAN JOSE TO SAN LUIS OBISPO
*** San Martin (Salinas) *** ***
*** Soledad *** ***
*** San Ardo *** ***
*** San Luis Obispo *** ***
SAN LUIS OBISPO TO LOS ANGELES
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 17
<Page>
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
*** Whitehills (Lompoc) *** ***
*** Santa Barbara *** ***
*** Ventura *** ***
*** Moorpark *** ***
SAN FRANCISCO TO OAKLAND
*** Oakland *** ***
OAKLAND TO SACRAMENTO
*** Suisun (Fairfield) (Jacksnipe Station) *** ***
OAKLAND TO SAN JOSE
LA TO SAN BERNARDINO
SAN BERNARDINO TO LAS VEGAS
*** San Bernardino *** ***
*** Slash X (Barstow) *** ***
*** Silver Lake *** ***
*** Primm (Kearny Pass) *** ***
LA TO SAN DIEGO
*** Corona *** ***
*** Escondido *** ***
SAN DIEGO TO PHOENIX
*** Live Oak Springs *** ***
*** El Centro *** ***
*** Yuma *** ***
*** Growler *** ***
*** Agua Caliente Rd *** ***
PHOENIX TO SANTA TERESA
*** La Palma *** ***
*** Tucson *** ***
*** Sibyl *** ***
*** Olga *** ***
*** Separ *** ***
*** Myndus *** ***
ST. LOUIS TO CHICAGO
*** Plainview *** ***
*** Springfield *** ***
*** Bloomington *** ***
*** Odell *** ***
*** Joliet *** ***
KANSAS CITY TO ST. LOUIS
*** Centerview *** ***
*** Syracuse *** ***
*** Tebbetts *** ***
*** Marthasville *** ***
OMAHA TO KANSAS CITY
*** Howe *** ***
*** Lancaster *** ***
OGDEN TO DENVER
*** Wahsatch *** ***
*** Carter (Elkhurst) *** ***
*** Green River *** ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 18
<Page>
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
*** Monell *** ***
*** Rawlins *** ***
*** Medicine Bow *** ***
*** Laramie *** ***
*** Stateline *** ***
*** Platteville *** ***
DENVER TO OMAHA
*** Weld Co. *** ***
*** Platner *** ***
*** Haigler *** ***
*** Culbertson *** ***
*** Edison *** ***
*** Heartwell *** ***
*** Grafton *** ***
*** Lincoln *** ***
SANTA TERESA TO STRATFORD
*** Orogrande (Elwood) *** ***
*** Tularosa *** ***
*** Ancho *** ***
*** Duran *** ***
*** Santa Rosa *** ***
*** Tucumcari *** ***
*** Romero *** ***
DENVER TO STRATFORD
*** Spruce (Monument) *** ***
*** Pinon (Pueblo) *** ***
*** Rocky Ford (N.Lajunta) *** ***
*** Frick *** ***
*** Campo (Baca Co. Line) *** ***
DALLAS TO MEMPHIS
*** Edgewood *** ***
*** Newsome *** ***
*** Roach *** ***
*** Guernsey *** ***
*** Arkadelphia *** ***
*** Little Rock *** ***
*** Biscoe *** ***
*** Widener *** ***
MEMPHIS TO NASHVILLE
*** Walnut *** ***
*** Lutts *** ***
*** Rockdale *** ***
DALLAS TO HOUSTON
*** Corsicana *** ***
*** Robbins *** ***
*** Dacus *** ***
HOUSTON TO NEW ORLEANS
*** Raywood (Devers) (N. Willis) *** ***
*** Pinehurst (Hwy 90/SR 109 ) *** ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 19
<Page>
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
*** Iowa (Kinder) (Mermentau) *** ***
*** Lafayette (Krotz Springs) (Oliver Sta.) *** ***
*** Baton Rouge (Chacahoula) *** ***
*** Sorrento *** ***
NEW ORLEANS TO TALLAHASSEE
*** Pearlington (Kiln) *** ***
*** Poplarville (White Crossing) *** ***
*** Hutson Lake *** ***
*** Mobile *** ***
*** Pensacola *** ***
*** Crestview *** ***
*** Bruce (Bonifay) *** ***
*** Clarksville (Sneads) *** ***
*** Tallahassee *** ***
FT. WORTH TO DALLAS
STRATFORD TO FT. WORTH
*** Dumas *** ***
*** Amarillo *** ***
*** Ashtola (Goodnight) *** ***
*** Carey *** ***
*** Tolbert *** ***
*** Wichita Falls *** ***
*** Fruitland *** ***
SAN ANTONIO TO HOUSTON
*** Luling *** ***
*** Weimar *** ***
*** East Bernard *** ***
SAN ANTONIO TO AUSTIN
*** Hunter *** ***
AUSTIN TO FT. WORTH
*** Bartlett *** ***
*** Waco *** ***
*** Itasca *** ***
LOUISVILLE TO CINCINNATI
*** Rexville *** ***
NASHVILLE TO LOUISVILLE
*** Reubensville *** ***
*** Nash *** ***
*** Irvington *** ***
ATLANTA TO CHARLOTTE
*** Bogart *** ***
*** Gluck *** ***
*** Spartanburg *** ***
CHARLOTTE TO RALEIGH
*** Salisbury *** ***
*** Greensboro *** ***
*** Oaks *** ***
ATLANTA TO JACKSONVILLE
*** Flovilla *** ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 20
<Page>
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
*** Gordon *** ***
*** Tarrytown *** ***
*** Surrency *** ***
*** Newell *** ***
ORLANDO TO MIAMI
*** Kenansville *** ***
*** Marcy *** ***
*** Bannock *** ***
JACKSONVILLE TO ORLANDO
*** St. Augustine *** ***
*** Deland *** ***
TAMPA TO MIAMI
*** Waterbury *** ***
*** E. Farmers Rd *** ***
*** Goodno *** ***
*** Deem City *** ***
TALLAHASSEE TO TAMPA
*** Perry *** ***
*** Chiefland *** ***
*** Chassahowtzka *** ***
NASHVILLE TO ATLANTA
*** Shelbyville *** ***
*** Huntsville *** ***
*** Blountsville *** ***
*** Birmingham *** ***
*** Howells Cove *** ***
*** Tallapoosa *** ***
STAMFORD TO HARTFORD
*** Bridgewater *** *** ***
HARTFORD TO PROVIDENCE
*** Chepachet, RI (Providence) *** *** ***
CLEVELAND TO BUFFALO
*** Saybrook *** ***
*** Wesleyville (Erie) *** ***
*** Sheridan *** ***
ALBANY TO BOSTON
*** Chicopee (Springfield) *** ***
*** Auburn (Worcester) *** ***
*** Stockbridge (Lee) *** ***
BALTIMORE TO WILMINGTON
*** Perryville *** *** ***
WASHINGTON DC TO BALTIMORE
*** Millersville *** *** ***
CHICAGO TO DETROIT
*** Gary *** ***
*** Niles *** ***
*** Kalamazoo *** ***
*** Albion *** ***
*** Dexter (Ann Arbor) *** ***
</Table>
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 21
<Page>
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
PITTSBURGH TO WASHINGTON DC
*** Uniontown *** ***
*** Cumberland *** ***
*** Big Pool *** ***
*** Frederick *** ***
DETROIT TO CLEVELAND
*** Toledo *** ***
*** Kimball *** ***
CLEVELAND TO PITTSBURGH
*** Akron *** ***
*** Columbiana (Kent State) (Salem) *** ***
CHICAGO TO INDIANAPOLIS
*** Crown Point *** ***
*** Wolcott *** ***
*** Frankfort *** ***
INDIANAPOLIS TO CINCINNATI
*** Greensburg *** ***
RICHMOND TO WASHINGTON DC
*** Dahlgren (Newburg) *** ***
RALEIGH TO RICHMOND
*** Wise *** ***
*** Dinwiddie *** ***
TORONTO TO BUFFALO
*** Toronto *** ***
*** Hamilton *** ***
MONTREAL TO ALBANY
*** Beekmantown *** ***
*** Factoryville *** ***
*** Moreau (Ft. Edward) *** ***
*** Albany *** ***
TORONTO TO OTTAWA
*** Peterborough *** ***
*** Tweed *** ***
*** Perth *** ***
OTTAWA TO MONTREAL
*** Ottawa *** ***
*** Champlain *** ***
*** Montreal *** ***
NEWARK TO PHILIDELPHIA
*** Princeton *** *** ***
</Table>
*The Assigned Space is the space allocated to Grantee for the Grantee Fibers
that have been ordered by Grantee as specified in Exhibit "B" of the Agreement
(as amended in the Second Amendment).
** First Additional Space will be available *** (or earlier, in Grantor's sole
discretion). First Additional Space in the *** segment should be available by
*** (or earlier, in Grantor's sole discretion).
*** Second Additional Space will be available by *** (or earlier, in Grantor's
sole discretion).
In raised floor facilities all *** standard suites can accommodate *** per the
Level 3 Dark Fiber Design Guideline.
Currently, all *** are raised floor facilities. All ILA's are On-Slab
facilities.
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 22
<Page>
<Table>
<Caption>
ADDITIONAL SQUARE FEET AVAILABLE
(APPROXIMATELY)
- -------------------------------------------------------------------------------------------------------------
FACILITY TYPE SEGMENT/SITE LOCATION ASSIGNED FIRST SECOND ADDITIONAL
SPACE* ADDITIONAL SPACE***
SPACE**
- -------------------------------------------------------------------------------------------------------------
</Table>
At Grantor's sole discretion, Grantor may provide *** in place of *** and *** in
place of ***.
Space and power will be delivered in accordance with the then existing Level 3
Dark Fiber Design Guidelines.
CONFIDENTIAL - EIGHTH AMENDMENT CONFIDENTIAL TREATMENT REQUEST
PAGE 23