JUDGMENT

Altamas Kabir, J.—When the application being I.A.No. 7/06 for revocation of the leave granted, filed by the respondent-union, was taken up for hearing, the appeal itself was taken up for disposal.

2. The Oil & Natural Gas Corporation Ltd. (hereinafter referred to as ‘the ONGC’ ) is a public sector undertaking constituted under the Oil & Natural Gas Commission Act to provide for production and sale of petroleum and petroleum products. In order to achieve these objects, the ONGC carries out geological and geophysical surveys for the exploration of petroleum. Such work of survey is seasonal and is confined to the period between November each year and April or May of the following year. The workload is far less during the monsoon period and is generally referred to as the off season. Every year when such survey work or field season begins, the ONGC starts recruiting casual/contingent/temporary workmen for specified periods and their service are terminated at the end of the field season. Such practice appears to have been continuing from the very inception of the ONGC in 1956. While in 1956, the ONGC had a staff strength of 450 employees, in course of time the numb