The board of the International Finance Corporation, the World Bank's investment agency, yesterday approved a $75 million loan to a subsidiary of Newmont Mining, the world's largest gold producer, for a project in Ghana that the investment agency's managers say they hope will be a model for the developing world. An alliance of advocacy and environmental groups urged the I.F.C. to postpone approval until it won additional safeguards to protect the thousands of people who are losing land and livelihoods to the gold mine's development, and to prevent contamination of drinking water from mine waste. But a senior official at the agency said the loan had been approved on the condition that the company meet stringent social and environmental standards... "The company is really committed, and the fact that they have deep pockets will help address many of these issues as they come up," said Rashad Kaldany, who heads the oil, gas, mining and chemicals department for the World Bank and its investment agency.