**NAS 9-97135**

**Modification 53**

**Page 2 of 3**

To implement the above, the following actions are taken:

1\. Paragraph 19. [Period of Performance]{.underline} is deleted in its
entirety and replaced with the following:

"19. [PERIOD OF PERFORMANCE]{.underline}

> \(a\) The period of performance of this contract shall be April 5,
> 1999 through April 4, 2003.

2\. Paragraph 21. [Firm-Fixed Price]{.underline} is deleted in its
entirety and replaced with the following:

"21. [FIRM-FIXED PRICE]{.underline}

The total firm-fixed price of this contract is
[\$7,314,801.09]{.underline}

3\. Paragraph 24. [SUBMISSION OF INVOICES]{.underline} is deleted in its
entirety and replaced with the following:

"24. [SUBMISSION OF INVOICES]{.underline}

Invoices furnished by the Contractor shall be distributed as follows:

NASA Johnson Space Center

Attn: (Distribute as indicated below)

2101 NASA Road One

Houston, TX 77058

[Distribute to:]{.underline} [No. of Copies]{.underline} [Phone
\#]{.underline}

Attn: BJ2/Donald L. Ward, Contract Specialist Original \# 1 copy
281-483-7553

GT4/Robert T. Anderson, COTR 1 copy 281-483-8803

LF/Je Y. Chang, Cost Accounting 1 copy 281-483-0860

LI/Jody M. Kovski 1 copy 281-483-8616

> \(a\) All charges for maintenance and operation services shall be
> invoiced in the month following the month for which such charges
> accrue. Each invoice shall contain the following information: contract
> number, description of services, price breakdowns on a summary and
> detailed level, while also reflecting the current month charges, and
> cumulative-to-date amounts. The Contractor must provide t he
> Government, electronically, the basis for the charges, in sufficient
> detail to permit evaluation of the invoice(s).

**NAS 9-97135**

**Modification 53**

**Page 3 of 3**

> \(b\) A Supplemental Report shall be submitted by the Contractor, with
> the 2nd invoice of the month, which will provide the following:

-   Breakout "Other Direct Costs (ODC)" by Task, and by Cumulative costs

-   Cumulative costs and all costs for the month should reconcile with
    the last invoice of the month

-   Invoice numbers (#) should be reflected on the supplemental report.

> Travel, as directed by the Government, will be a direct cost to the
> contract based on actual airfare and per diem rates per the most
> current Official CONUS Per Diem Rates, located at
> [www.dtic.mil/cgi-bin/cpdrates.pl](http://www.dtic.mil/cgi-bin/cpdrates.pl)

\(c\) The Contractor may invoice the Government on a monthly or
bi-monthly basis.

> In order to alleviate separate billing for each Task, the Contractor
> shall provide a single invoice listing all Tasks (i.e. Services
> purchased), and their respective charges for the billing period. This
> information shall be provided in chronological order by Task.
>
> Invoices are due 10 (ten) working days after the close of the
> contractor's billing cycle.

\(d\) Funds Disbursed via Electronic Funds Transfer (EFT)

> The contractor shall request and submit to the Government an SF 3881,
> "Payment Information Form."
>
> If your payments are to be made to a financial institution, furnish
> NASA/JSC with an original copy of the assignment (must enclose
> original signatures and seal), with an accompanying letter for the
> NASA Contracting Officer's approval.