Ten years ago, Wal-Mart was for many Maine communities just a small cloud on the horizon. For some people it was a promise of better shopping opportunities and commercial development. For others it was a threat.

Wal-Mart sent in its top spokesman, Don Shinkle, then vice president for public affairs, to ease the local anxieties. Mr. Shinkle spoke bluntly. Some local businesses would fail, he told a gathering in Rockland. But he added that the ones that failed would soon have gone belly up even without the new competition. He said that the survivors would have to lengthen their business hours, bring in new brands of merchandise, offer a variety of sizes and styles, adopt flexible return policies, and provide special customer services. As an example, he said they could supply batteries for electronic items.

Some businesses found they could cope. Some even benefited from increased traffic brought to their areas by big new Wal-Mart stores. Others lost to the new competition and are gone. And some downtowns felt a loss as new Wal-Marts found sites outside of town and hastened urban sprawl. By and large, communities adapted.

Now comes a new kind of Wal-Mart and a new kind of competition. Wal-Mart “supercenters,” proposed for Bangor, Ellsworth, Rockland, and other cities, will be two or three times as big and will offer much more. Besides the pesent clothing, pharmacy, hardware, photo, gardening, automotive, office-supply, and kitchenware departments, they will offer groceries and probably optometry, hair-dressing, greetings cards, picture framing, and almost anything else you could think of.

Again, Wal-Mart will be telling the locals how to cope. Keith Morris, the company’s regional public relations manager, is scheduled to speak with local business people Tuesday at an Eggs and Issues breakfast sponsored by the Ellsworth Area Chamber of Commerce. Mr. Morris says that coping with the new supercenters involves the same basic principles. The only new competition will be in groceries, but the present supermarkets will continue to have one advantage. The supercenters will not provide prepared foods, whereas Shaw’s and Shop ‘n Save have been expanding their delicatessen departments in an era where many families now pick up prepared dinners instead of cooking at home.

Does this mean smooth sailing for local businesses? One leading Rockland businessman doesn’t think so. He scoffs privately at the welcoming tone by some cities, saying they are interested only in an expanded tax base. He says the new Wal-Mart objective is to put every conceivable retail group into the supercenter so that no one will go anywhere else to shop. “Downtown in a Box,” he calls it.

Mr. Morris says he doesn’t understand that description. He and other corporate representatives will be assuring local businesses that with flexibility and energy they can cope.

Mr. Shinkle, incidentally, retired from Wal-Mart and is now president of the Jefferson City, Mo., chamber of commerce. He says Jefferson City got a Wal-Mart supercenter three years ago and not one local business has gone under or is about to. Maine communities will have a hard time utterly stopping these stores, but they certainly can, with deft planning, direct them to parts of town where they will enhance the entire business climate. Call it a coping strategy.