Exhibit 99.1

[RYDER SCOTT COMPANY LETTERHEAD]

March 10, 2008

Edge
Petroleum Corporation
1301 Travis Street, Suite 2000
Houston, Texas 77002

Gentlemen:

At
your request, we have prepared an estimate of the reserves, future production, and income attributable to certain leasehold and royalty interests of Edge Petroleum Corporation (Edge)
as of December 31, 2007. The subject properties are located in the states of Alabama, Arkansas, Louisiana, Michigan, Mississippi, New Mexico, and Texas. The income data were estimated using the
Securities and Exchange Commission (SEC) guidelines for future price and cost parameters.

The
estimated reserves and future income amounts presented in this report are related to hydrocarbon prices. December 31, 2007 hydrocarbon prices were used in the preparation of
this report as required by SEC guidelines; however, actual future prices may vary significantly from December 31, 2007 prices. Therefore, volumes of reserves actually recovered and amounts of
income actually received may differ significantly from the estimated quantities presented in this report. The results of this study are summarized below.

SEC PARAMETERS  Estimated Net Reserves and Income Data  Certain Leasehold and Royalty Interests of  Edge Petroleum Corporation  As of December 31, 2007

|                       |                         | Proved
|---------------------- | ----------------------- | ------
|
|
|
|Net Remaining Reserves |                         |       
|                       | Oil/CondensateBarrels  |       
|                       | Plant ProductsBarrels  |       
|                       | GasMMCF                |       
|Income Data ($M)       |                         |       
|                       | Future Gross Revenue    |       
|                       | Deductions              |       
|                       |                         |       
|                       | Future Net Income (FNI) |       
|                       | Discounted FNI @ 10%    |       

Liquid
hydrocarbons are expressed in standard 42 gallon barrels. All gas volumes are sales gas expressed in millions of cubic feet (MMCF) at the official temperature and pressure bases
of the areas in which the gas reserves are located.

1200, 530 8TH AVENUE, S.W. CALGARY, ALBERTA T2P 3S8

TEL (403) 262-2799

FAX (403) 262-2790621 17TH STREET, SUITE 1550 DENVER, COLORADO 80293-1501

TEL (303) 623-9147

FAX (303) 623-4258


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The future gross revenue is after the deduction of production taxes. The deductions are comprised of the normal direct costs of operating the
wells, ad valorem taxes, recompletion costs, and development costs. The future net income is before the deduction of state and federal income taxes and general administrative overhead, and has not
been adjusted for outstanding loans that may exist nor does it include any adjustment for cash on hand or undistributed income. No attempt was made to quantify or otherwise account for any accumulated
gas production imbalances that may exist. Gas reserves account
for approximately 64 percent and liquid hydrocarbon reserves account for the remaining 36 percent of total future gross revenue from proved reserves.

The
discounted future net income shown above was calculated using a discount rate of 10 percent per annum compounded monthly. Future net income was discounted at four other
discount rates which were also compounded monthly. These results are shown on each estimated projection of future production and income presented in a later section of this report and in summary form
below.

Discounted Future Net Income ($M)
As of December 31, 2007Discount Rate Percent

Total
Proved12

$
501,893.715

$
457,434.020

$
398,788.825

$
353,694.3


The
results shown above are presented for your information and should not be construed as our estimate of fair market value.

Reserves Included in This Report

Theproved reservesincluded herein conform to the definition as set forth in the Securities and Exchange
Commission's Regulation S-X Part 210.4-10 (a) as clarified by subsequent Commission Staff Accounting Bulletins. The definitions of proved reserves are
included in the section entitled "Petroleum Reserves Definitions" which is attached with this report.

Because
of the direct relationship between volumes of proved undeveloped reserves and development plans, we include in the proved undeveloped category only reserves assigned to
undeveloped locations that we have been assured will definitely be drilled, and reserves assigned to the undeveloped portions of secondary or tertiary projects which we have been assured will
definitely be developed.

The
proved developed non-producing reserves included herein are comprised of shut-in and behind pipe categories. The various reserve status categories are defined
in the section entitled "Petroleum Reserves Definitions" which is attached with this report.

Estimates of Reserves

In general, the reserves included herein were estimated by performance methods or the volumetric method; however, other methods were used in certain cases where
characteristics of the data indicated such other methods were more appropriate in our opinion. The reserves estimated by the performance method utilized extrapolations of various historical data in
those cases where such data were definitive. Reserves were estimated by the volumetric method in those cases where there were inadequate historical performance data to establish a definitive trend or
where the use of production performance data as a basis for the reserve estimates was considered to be inappropriate.

The
reserves included in this report are estimates only and should not be construed as being exact quantities. They may or may not be actually recovered, and if recovered, the revenues
therefrom and

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the
actual costs related thereto could be more or less than the estimated amounts. Moreover, estimates of reserves may increase or decrease as a result of future operations.

Future Production Rates

Initial production rates are based on the current producing rates for those wells now on production. Test data and other related information were used to estimate
the anticipated initial production rates for those wells or locations which are not currently producing. If no production decline trend has been established, future production rates were held
constant, or adjusted for the effects of curtailment where appropriate, until a decline in ability to produce was anticipated. An estimated rate of decline was then applied to depletion of the
reserves. If a decline trend has been established, this trend was used as the basis for estimating future production rates. For reserves not yet on production, sales were estimated to commence at an
anticipated date furnished by Edge.

The
future production rates from wells now on production may be more or less than estimated because of changes in market demand or allowables set by regulatory bodies. Wells or locations
which are not currently producing may start producing earlier or later than anticipated in our estimates of their future production rates.

Hydrocarbon Prices

Edge furnished us with hydrocarbon prices in effect at December 31, 2007, and with its forecasts of future prices which take into account SEC and Financial
Accounting Standards Board (FASB) rules, current market prices, contract prices, and fixed and determinable price escalations where applicable.

In
accordance with FASB Statement No. 69, December 31, 2007, market prices were determined using the daily oil price or daily gas sales price ("spot price") adjusted for
oilfield or gas gathering hub and wellhead price differences (e.g. grade, transportation, gravity, sulfur and BS&W) as appropriate. Also in accordance with SEC and FASB specifications, changes
in market prices subsequent to December 31, 2007 were not considered in this report.

For
hydrocarbon products sold under contract, the contract price including fixed and determinable escalations, exclusive of inflation adjustments, was used until expiration of the
contract. Upon contract expiration, the price was adjusted to the current market price for the area and held at this adjusted price to depletion of the reserves.

Costs

Operating costs for the leases and wells in this report are based on information provided by Edge and include only those costs directly applicable to the leases
or wells. When applicable, the operating costs include a portion of general and administrative costs allocated directly to the leases and wells under terms of operating agreements. No deduction was
made for indirect costs such as general administration and overhead expenses, loan repayments, interest expenses, and exploration and development prepayments that are not charged directly to the
leases or wells.

Development
costs were furnished to us by Edge and are based on authorizations for expenditure for the proposed work or actual costs for similar projects. The estimated net cost of
abandonment after salvage was included for properties where abandonment costs net of salvage are significant. At the request of Edge, their estimate of zero abandonment costs after salvage value for
onshore properties
was used in this report. Ryder Scott has not performed a detailed study of the abandonment costs nor the salvage value and makes no warranty for Edge's estimate.

Current
costs were held constant throughout the life of the properties.

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General

While it may reasonably be anticipated that the future prices received for the sale of production and the operating costs and other costs relating to such
production may also increase or decrease from existing levels, such changes were, in accordance with rules adopted by the SEC, omitted from consideration in making this evaluation.

The
estimates of reserves presented herein were based upon a detailed study of the properties in which Edge owns an interest; however, we have not made any field examination of the
properties. No consideration was given in this report to potential environmental liabilities which may exist nor were any costs included for potential liability to restore and clean up damages, if
any, caused by past operating practices. Edge has informed us that they have furnished us all of the accounts, records, geological and engineering data, and reports and other data required for this
investigation. The ownership interests, prices, and other factual data furnished by Edge were accepted without independent verification. The estimates presented in this report are based on data
available through December 2007.

Edge
has assured us of their intent and ability to proceed with the development activities included in this report, and that they are not aware of any legal, regulatory or political
obstacles that would significantly alter their plans.

Neither
we nor any of our employees have any interest in the subject properties and neither the employment to make this study nor the compensation is contingent on our estimates of
reserves and future income for the subject properties.

This
report was prepared for the exclusive use and sole benefit of Edge Petroleum Corporation and may not be put to other use without our prior written consent for such use. The data,
work papers, and
maps used in this report are available for examination by authorized parties in our offices. Please contact us if we can be of further service.

|       |  | Very truly yours,                                                        
|------ |  | -------------------------------------------------------------------------
|       |  | RYDER SCOTT COMPANY, L.P.                                                
|[SEAL] |  | /s/ Michael F. StellMichael F. Stell, P.E. Managing Senior Vice President

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PETROLEUM RESERVES DEFINITIONS        SECURITIES AND EXCHANGE COMMISSION

INTRODUCTION

Reserves are those quantities of petroleum which are anticipated to be commercially recovered from known accumulations from a given date forward. All reserve
estimates involve some degree of uncertainty. The uncertainty depends chiefly on the amount of reliable geologic and engineering data available at the time of the estimate and the interpretation of
these data. The relative degree of uncertainty may be conveyed by placing reserves into one of two principal classifications, either proved or unproved. Unproved reserves are less certain to be
recovered than proved reserves and may be further sub-classified as probable and possible reserves to denote progressively increasing uncertainty in their recoverability. It should be
noted that Securities and Exchange Commission Regulation S-K prohibits the disclosure of estimated quantities of probable or possible reserves of oil and gas and any estimated value
thereof in any documents publicly filed with the Commission.

Reserves
estimates will generally be revised as additional geologic or engineering data become available or as economic conditions change. Reserves do not include quantities of petroleum
being held in inventory, and may be reduced for usage or processing losses if required for financial reporting.

Reserves
may be attributed to either natural energy or improved recovery methods. Improved recovery methods include all methods for supplementing natural energy or altering natural
forces in the reservoir to increase ultimate recovery. Examples of such methods are pressure maintenance, cycling, waterflooding, thermal methods, chemical flooding, and the use of miscible and
immiscible displacement fluids. Other improved recovery methods may be developed in the future as petroleum technology continues to evolve.

PROVED RESERVES (SEC DEFINITIONS)

Securities and Exchange Commission Regulation S-X Rule 4-10 paragraph (a) defines proved reserves as follows:

Proved oil and gas reserves.Proved oil and gas reserves are the estimated
quantities of crude oil, natural gas, and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable in future years from known reservoirs under
existing economic and operating conditions, i.e., prices and costs as of the date the estimate is made. Prices include consideration of changes in existing prices provided only by contractual
arrangements, but not on escalations based upon future conditions.



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Proved developed oil and gas reserves.Proved developed oil and gas reserves
are reserves that can be expected to be recovered through existing wells with existing equipment and operating methods. Additional oil and gas expected to be obtained through the application of fluid
injection or other improved recovery techniques for supplementing the natural forces and mechanisms of primary recovery should be included as "proved developed reserves" only after testing by a pilot
project or after the operation of an installed program has confirmed through production response that increased recovery will be achieved.

Proved undeveloped reserves.Proved undeveloped oil and gas reserves are
reserves that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion. Reserves on undrilled acreage
shall be limited to those drilling units offsetting productive units that are reasonably certain of production when drilled. Proved reserves for other undrilled units can be claimed only where it can
be demonstrated with certainty that there is continuity of production from the existing productive formation. Under no circumstances should estimates for proved undeveloped reserves be attributable to
any acreage for which an application of fluid injection or other improved recovery technique is contemplated, unless such techniques have been proved effective by actual tests in the area and in the
same reservoir.

Certain
Staff Accounting Bulletins published subsequent to the promulgation of Regulation S-X have dealt with matters relating to the application of financial
accounting and disclosure rules for oil and gas producing activities. In particular, the following interpretations extracted from Staff Accounting Bulletins set forth the Commission staff's view on
specific questions pertaining to proved oil and gas reserves.

Economic producibility of estimated proved reserves can be supported to the satisfaction of the Office of Engineering if geological and engineering data
demonstrate with reasonable certainty that those reserves can
be recovered in future years under existing economic and operating conditions. The relative importance of the many pieces of geological and engineering data which should be evaluated when classifying
reserves cannot be identified in advance. In certain instances, proved reserves may be assigned to reservoirs on the basis of a combination of electrical and other type logs and core analyses which
indicate the reservoirs are analogous to similar reservoirs in the same field which are producing or have demonstrated the ability to produce on a formation test. (extracted from
SAB-35)

In determining whether "proved undeveloped reserves" encompass acreage on which fluid injection (or other improved recovery technique) is contemplated, is it
appropriate to distinguish between (i) fluid injection used for pressure maintenance during the early life of a field and (ii) fluid injection used to effect secondary recovery when a
field is in the late stages of depletion?... The Office of Engineering believes that the distinction identified in the above question may be appropriate in a few limited circumstances, such as in the
case of certain fields in the North Sea. The staff will review estimates of proved reserves attributable to fluid injection in the light of the strength of the evidence presented by the registrant in
support of a contention that enhanced recovery will be achieved. (extracted from SAB-35)

Companies should report reserves of natural gas liquids which are net to their leasehold interest, i.e., that portion recovered in a processing plant and
allocated to the leasehold interest. It may be appropriate in the case of natural gas liquids not clearly attributable to leasehold interests ownership to follow instruction (b) of
Item 2(b)(3) of Regulation S-K and report such reserves separately and describe the nature of the ownership. (extracted from SAB-35)

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The staff believes that since coalbed methane gas can be recovered from coal in its natural and original location, it should be included in proved reserves,
provided that it complies in all other respects with the definition of proved oil and gas reserves as specified in Rule 4-10(a)(2) including the requirement that methane production
be economical at current prices, costs, (net of the tax credit) and existing operating conditions. (extracted from SAB-85)

Statements
in Staff Accounting Bulletins are not rules or interpretations of the Commission nor are they published as bearing the Commission's official approval; they represent
interpretations and practices followed by the Division of Corporation Finance and the Office of the Chief Accountant in administering the disclosure requirements of the Federal securities laws.

SUB-CATEGORIZATION OF DEVELOPED RESERVES (SPE/WPC DEFINITIONS)

In accordance with guidelines adopted by the Society of Petroleum Engineers (SPE) and the World Petroleum Congress (WPC), developed reserves may be
sub-categorized as producing or non-producing.

Producing.Reserves sub-categorized as producing are expected to be recovered from
completion intervals which are open and producing at the time of the estimate. Improved recovery reserves are considered producing only after the improved recovery project is in operation.

Non-Producing.Reserves sub-categorized as non-producing include
shut-in and behind pipe reserves. Shut-in reserves are expected to be recovered from (1) completion intervals which are open at the time of the estimate but which have
not started producing; (2) wells which were shut-in awaiting pipeline connections or as a result of a market interruption; or (3) wells not capable of production for
mechanical reasons. Behind pipe reserves are expected to be recovered from zones in existing wells, which will require additional completion work or future recompletion prior to the start of
production.

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