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                                                                   EXHIBIT 99.11


                                 March 25, 1999




Mr. Ron E. Hooper
Burlington Resources Coal Seam
   Gas Royalty Trust
NationsBank of Texas, N.A., Trustee
NationsBank Plaza
901 Main Street, 17th Floor
Dallas, Texas  75202

Dear Mr. Hooper:

     In accordance with your request, we have estimated, as of December 31,
1998, the (1) future net revenue to the Burlington Resources Coal Seam Gas
Royalty Trust (Trust) net profits interest and (2) proved reserves to the
Burlington Resources Oil & Gas Company (Burlington) interest in the Fruitland
Coal Formation underlying the Northeast Blanco Unit, Rio Arriba and San Juan
Counties, New Mexico, as listed in the accompanying tabulations. The Trust net
profits interest is derived from the Burlington interest in such proved
reserves. This report has been prepared using constant prices and costs and
conforms to the guidelines of the Securities and Exchange Commission (SEC).

     The estimated net proved reserves in this report are defined as the portion
of the gross reserves attributable to the Burlington interest to which the net
profits interest is applied. As presented in the accompanying summary
projection, Table I, we estimate the Burlington net reserves and future net
revenue to the Trust net profits interest, as of December 31, 1998, to be:

<TABLE>
<CAPTION>

                                     Burlington Net Reserves                      Trust Future Net Revenue
                                -----------------------------------      -------------------------------------------
                                  Condensate             Gas                                       Present Worth
        Category                  (Barrels)             (MCF)                  Total                   at 10%
--------------------------      ---------------     ---------------      -------------------     -------------------
<S>                            <C>                 <C>                   <C>                     <C>        
Proved Developed                      0               64,535,184            $49,634,900             $30,291,100
</TABLE>

     Gas volumes are expressed in thousands of standard cubic feet (MCF) at the
contract temperature and pressure bases. These properties no longer produce
commercial volumes of condensate.

     This report includes a summary projection of reserves and revenue along
with one-line summaries of reserves, economics, and basic data by lease. For the
purposes of this report, the term "lease" refers to a single economic
projection.

     The estimated reserves and future revenue shown in this report are for
proved developed reserves only. Our study indicates that there are no proved
undeveloped reserves for these properties

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at this time. In accordance with SEC guidelines, our estimates do not include
any value for probable or possible reserves which may exist for these
properties. This report does not include any value which could be attributed to
interests in undeveloped acreage.

         Future gross revenue in this report is to the Burlington interest prior
to deducting state production taxes and ad valorem taxes. Future net revenue is
the 95 percent net profits interest share to the Trust after deducting the
Burlington working interest share of these taxes, future capital costs, and
operating expenses, but before consideration of federal income taxes. Our
estimates of future net revenue have not been adjusted to account for the
Section 29 nonconventional fuels federal income tax credit. In accordance with
SEC guidelines, the future net revenue has been discounted at an annual rate of
10 percent to determine its "present worth." The present worth is shown to
indicate the effect of time on the value of money and should not be construed as
being the fair market value of the Trust net profits interest.

         For the purposes of this report, a field inspection of the properties
has not been performed nor has the mechanical operation or condition of the
wells and their related facilities been examined. We have not investigated
possible environmental liability related to the properties; therefore, our
estimates do not include any costs which may be incurred due to such possible
liability. Also, our estimates do not include any salvage value for the lease
and well equipment nor the cost of abandoning the properties.

         The gas price used in this report is based on the December 1998 price
received, adjusted for BTU content, the gathering fee, and shrinkage. This price
is also adjusted as specified in the gas purchase contract under provisions
related to the sharing price and price credit account and is held constant in
accordance with SEC guidelines.

         Lease and well operating costs are based on operating expense records
provided by Burlington and the Trustee. These costs include the per-well
overhead expenses allowed under joint operating agreements along with costs
estimated to be incurred at and below the district and field levels. General and
administrative overhead expenses of Burlington and the Trustee are not included.
Lease and well operating costs are held constant in accordance with SEC
guidelines. Capital costs are included as required for workovers and production
equipment.

         We have made no investigation of potential gas volume and value
imbalances which may have resulted from overdelivery or underdelivery to the
Burlington interest. Therefore, our estimates of reserves and future revenue do
not include adjustments for the settlement of any such imbalances; our
projections are based on Burlington receiving its net revenue interest share of
estimated future gross gas production.

         The reserves included in this report are estimates only and should not
be construed as exact quantities. They may or may not be recovered; if
recovered, the revenues therefrom and the costs related thereto could be more or
less than the estimated amounts. The sales rates, prices received for the
reserves, and costs incurred in recovering such reserves may vary from
assumptions included in this report due to governmental policies and
uncertainties of supply and demand. Also, estimates of reserves may increase or
decrease as a result of future operations.


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         In evaluating the information at our disposal concerning this report,
we have excluded from our consideration all matters as to which legal or
accounting, rather than engineering and geological, interpretation may be
controlling. As in all aspects of oil and gas evaluation, there are
uncertainties inherent in the interpretation of engineering and geological data;
therefore, our conclusions necessarily represent only informed professional
judgments.

         The titles to the properties have not been examined by Netherland,
Sewell & Associates, Inc., nor has the actual degree or type of interest owned
been independently confirmed. The data used in our estimates were obtained from
Burlington Resources Oil & Gas Company, the Trustee, and the nonconfidential
files of Netherland, Sewell & Associates, Inc. and were accepted as accurate. We
are independent petroleum engineers, geologists, and geophysicists; we do not
own an interest in these properties and are not employed on a contingent basis.
Basic geologic and field performance data together with our engineering work
sheets are maintained on file in our office.

                                        Very truly yours,


                                        /s/ FREDERIC D. SEWELL


DDS:PJA