As hearing opened yesterday on the Potomac Electric Power Co. request for a $15.5 million rate increase in the District of Columbia, a Pepco lawyer stood before the D.C. Public Service Commission and said the company needs another $3.2 million on top of that to make ends meet.

The price has gone up that much because of inflation in the past few months since Pepco filed its request, company officers said.

Altogether, Pepco's rates increase requests pending before the commission now total $63.7 million-more than a 20 percent increase that would add more than $4.20 to an average monthly residential bill of $19.91 if granted by the commission.

The new $3.2 million request came at a commission hearing yesterday on Pepco's seventh major rate increase request in nine years. The commission expects to spend most of this year hearing and deciding the case.

The commission has spent two years hearing and deciding a previous case, and still has not issued a decision. The company claims this "regulatory lag" has hurt it financially.

In yesterday's hearing, D.C. People's Counsel Brian Lederer charged that the company had undermined his office by refusing to pay a $25,000 as sessment charge so that the office, which officially represents consumers in rate cases, can hire experts to testify on its side.

Under the law, Pepco must pay such assessments so that the People's Counsel can carry on its cases. Company attorneys argued yesterday that the assessments are improper because Lederer's office is not supervised in its spending of the funds.

In the last rate case-the one still pending a decision after two years-Lederer assessed Pepco and spent $440,000 to hire attorneys and expert witnesses. Lederer said yesterday that the expenditure was worth it because far more than that sum was saved in lower electric rates.

A Pepco attorney told the commission yesterday that the company would pay Lederer's assessments in the current case but only "under protest" and until the issue is resolved in the courts.

Lederer said he could not continue in the case because the uncertainty of receiving the payments under protest disrupted the work routine of his office and made it impossible for him effectively to represent the interests of utility ratepayers.

The commission recessed without making a decision on whether to continue the case without Lederer.