This is to clarify some aspects of the letter written by Jose del Carmen Ariza, ambassador of the Dominican Republic {July 29}, about the presidential elections held in the Dominican Republic on May 16. He said that:

* A high percentage of voters participated in the election. However, the report says that the Central Electoral Board did not control the issuing of voting identification cards. It has been proven that there was a high number of false voting ID cards. Thus, there is no way to establish a credible percentage of voting participation or abstention.

* Since 1990 the government has worked to improve the Dominican electoral system. He didn't mention that in 1990 President Joaquin Balaguer manipulated the elections and remains in power. In this election, the Central Electoral Board issued two voter registration rolls, one to all political parties on May 12, yet different rolls to disenfranchised voters at voting polls on election day -- May 16.

* Only a few citizens were prevented from voting. However, the report states an average of 20 disenfranchised voters per voting poll.

* The total number of disenfranchised voters is 45,000. The report indicates this represents only 1,468 voting polls (14.9 percent) of the 9,553 that were displayed across the country on election day. Projections indicate that the presidential electoral results could have been reversed in the Dominican Republic. Instead of a 30,000-vote margin in favor of Mr. Balaguer, the results would have been as much as 221,000 votes in favor of the opposition presidential candidate, Jose Francisco Pena Gomez;

* The disenfranchisement was caused by a computer problem. The Verification Commission report disregarded that possibility because 60 percent of voters' names that were illegally used to replace those of legitimate voters have not been found in the master computer registration file available at the Central Electoral Board.

On May 5 and 6, when the voting registration rolls were printed, the Central Electoral Board did not allow anyone, including international observers (except computer center employees), to enter its computer center. The Central Electoral Board also mysteriously does not have either the computer file or copies of the printed voting registration rolls distributed among voting polls on election day.

The opposition presidential candidate party has information that a resolution for the Central Electoral Board to declare Mr. Balaguer as "winner" has been drafted three times at the presidential palace, but that government officials are trying to find what they think must be the most "acceptable" text to convince the international community.

JOSE A. GARCIA

Silver Spring

The writer is director of electoral affairs for the Dominican Revolutionary Party.