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                                                                      EXHIBIT 18

                          [ARTHUR ANDERSEN LETTERHEAD]


August 2, 1999

Newpark Resources, Inc.
3850 North Causeway Blvd., Suite 1770
Metairie, LA  70002-1752

Gentlemen:

This letter is written to meet the requirements of Regulation S-K calling for a
letter from a registrant's independent accountants whenever there has been a
change in accounting principle or practice.

We have been informed that, effective as of January 1, 1999, the Company changed
from the straight-line method of providing depreciation for its waste disposal
assets and its barite grinding mill assets to the unit-of-production method. It
is the opinion of the Company's management that the unit-of-production method
for the waste disposal assets and barite grinding mill assets, based on the
factors described below, more accurately reflects results of operations.

In applying the straight-line method, the useful lives for the waste disposal
assets were developed assuming a relatively constant annual volume of the
expected waste streams. However, the actual volume of waste disposed by the
Company has been more volatile than expected given the cyclical nature of oil
and gas drilling in the markets which Newpark serves, and volatility in
utilization rates are expected to continue. Because the utility of disposal
assets is diminished by volume of waste disposed rather than time, the Company
believes the unit-of-production method provides a better measure of loss of
utility of the disposal assets. In addition, a review of major competitors in
the industrial waste business indicates that the unit-of-production method is a
common method of depreciation used for surface disposal assets utilized in this
industry.

The original useful life for the barite grinding mills was developed based on
maximum utilization rates which considered non-utilized time only for scheduled
repair periods. The Company's actual utilization rates closely followed this
pattern from inception of operations (1997) through July 1998. As with the
disposal assets, the utilization rates have become more volatile than expected.
The life of a barite grinding mill and equipment is affected primarily by the
volume of barite material ground in the mill, not passage of time. As a result,
consistent with the waste disposal assets, the Company believes the
unit-of-production method provides a better measure of diminution of utility of
these assets.

In applying the unit-of-production method of providing depreciation, the Company
makes estimates of certain factors which are involved in determining the
expected productive units for its waste disposal assets and barite grinding mill
assets. The capacity of the waste disposal assets was determined based primarily
on seismic and geological studies, and the barite grinding mill assets was based
primarily on

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Newpark Resources, Inc.
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August 2, 1999

manufacturer's certifications and the capacity of other similar assets. These
factors also include consideration of obsolescence and periods of non-use.

A complete coordinated set of financial and reporting standards for determining
the preferability of accounting principles among acceptable alternative
principles has not been established by the accounting profession. Thus, we
cannot make an objective determination of whether the change in accounting
described in the preceding paragraph is to a preferable method. However, we have
reviewed the pertinent factors, including those related to financial reporting,
in this particular case on a subjective basis, and our opinion stated below is
based on our determination made in this manner.

We are of the opinion that the Company's change in method of accounting is to an
acceptable alternative method of accounting, which, based upon the reasons
stated for the change and our discussions with you, is also preferable under the
circumstances in this particular case. In arriving at this opinion, we have
relied on the business judgment and business planning of your management.

We have not audited the application of this change to the financial statements
of any period. Further, we have not examined and do not express any opinion with
respect to your financial statements for any period including for the three
months and six months ended June 30, 1999.

Very truly yours,




ARTHUR ANDERSEN LLP