The dramatic rise and fall of silver prices that shook the nation's financial markets last year could easily happen again, warns a study by four government agencies that will be delivered to Congress today.

"The enormous resources available to a wealthy speculator or a foreign government pose special threats" to commodity markets, the year-long study concludes.

"A wealthy group of traders could acquire quantities of a commodity through cash and futures transactions and unduly affect the commodity's price level and volatility."

The potential for a recurrance of "Silver Thursday" -- when the metal's market collapsed on March 27, 1980 -- is analyzed in a 500-page study prepared by the Commodity Futures Trading Commission, Securities and Exchange Commission, Federal Reserve Board and Treasury Department.

Congress ordered the agencies to report on what caused the price of silver to balloon to $50 an ounce and then collapse to $10.80 and will get its answer today. A copy of the final draft of the study was obtained yesterday by The Washingtion Post.

The study carefully avoids blamming anyone for what happened, eplaining that the CFTC and the SEC are both investigating possible illegal activities in the silver market.

In an effort to protect the two enforcement investigations, the report to Congress omits many details of what the two agencies know about the silver market incidents, say sources familiar with the investigation and the report.

The result is a somewhat bland document, long on theoretical discussions of how the silver market behaved the short on conclusions about what if anything, was wrong.

The SEC already has been sued for allegedly violating the right to the financial privacy of one of the targets of its investigation, the billionaire Hunt family of Texas. A federal judge in Texas is expected to decide next week whether to limit the SEC probe because of the alleged invasion of the Hunts' privacy.

The congressional study offers little new information about the silver buying spree that involved the Hunts, several Arab investors who were partners of the Hunts and a second group including foreign investors who have kept their identities secret by using Swiss bank accounts.

The two groups have been accused of conspiring to corner the silver market, the study says, but "the information available to the study group does not indicate whether they did or did not act in concert."

The report, however, specifically rejects the Hunts' claim that they were the victims rather than the cause of the collapse of silver prices.

The Hunts have claimed repeatedly that the reason silver prices collapsed was that the rules of the silver market were changed by the boards of the Commodity Exchange Inc. in New York and the Chicago Board of Trade.

According to Nelson Bunker Hunt and W. Herbert Hunt, board members of the two exchanges had conflicts of interests and stood to profit from the fall of silver prices.

"The study group was unable to develop evidence of bad faith on the part of either the exchanges or their board members," the report concludes.

"The study group did not uncover evidence to support the claims that Comex or CBOT rule change actions were implemented in bad faith to force silver prices down." But possible conflicts of interest by at least one board member still are being investigated, a footnote in the report discloses.

Without alleging any improprieties, the study suggests that silver's rollercoaster ride was exaggerated by the methods used by the Hunts and the second group to buy silver.

Rather then buy silver from mines or metals dealers, they bought contracts for future delivery of silver on the Comex and Chicago Board of Trade. Most customers of those market sell their contracts for cash, but the two groups waited for the contracts to come due and took the silver.