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                                                                    Exhibit 99.1




VIROGROUP INC. ANNOUNCES EXECUTION OF MERGER AGREEMENT

JUNE 23, 1998

NASHVILLE, Tenn.-(BUSINESS WIRE-June 23, 1998-ViroGroup Inc. (OTC: VIRO) today
announced that it has entered into a definitive agreement with Laidlaw
Environmental Services Inc. relating to the acquisition by Laidlaw of the
approximately 50% of the outstanding shares of ViroGroup not currently owned by
Laidlaw or its affiliates for $0.75 in cash per share. The transaction is
subject to approval of the shareholders of ViroGroup.

ViroGroup provides a full range of environmental, hydrogeological,
hazardous-waste and solid-waste management services nationwide to correct and
improve air, water and soil quality. Most of the company's revenues are derived
from the assessment and remediation of groundwater and soil contaminants and the
design, permitting, construction management and compliance monitoring of
waste-management facilities.

For further information, please contact Jeffrey B. Meskin at Morgan Keegan &
Company at 1-800-366-7426 or 901/579-4834.