Step 1: Understanding the UNCITRAL Model Law and Arbitration Act.
The UNCITRAL Model Law on International Commercial Arbitration does not automatically become part of the Indian Arbitration Act, 1996. It is only used as a guide to interpret and understand the provisions of the Indian Arbitration Act. The case of *Union of India Vs East Coast Boat Builders and Engineers Ltd.* clarified that the Model Law does not directly form part of the Arbitration Act.
Step 2: Explanation of Other Options.
- (b) *Union of India Vs M.C. Mehta* concerns environmental law, not the application of the UNCITRAL Model Law to the Arbitration Act.
- (c) *Union of India Vs State of India* is unrelated to the interpretation of the Arbitration Act.
- (d) *Union of India Vs Indian Change Chrome Ltd.* does not pertain to the Model Law's role in the Arbitration Act.
Step 3: Conclusion.
The correct case where the UNCITRAL Model Law was discussed as not being part of the Arbitration Act is *Union of India Vs East Coast Boat Builders and Engineers Ltd.*.