A consumer bill of rights being considered by the D.C. Public Service Commission would cost District utility customers more than $7 million a year in rate increases if implemented, according to the gas, electric and telephone companies.

The proposed bill contains stringent new provisions - mostly favoring customers - on billing, service cutoff, security deposits and the handling of customer complaints that the companies say would be expensive and would be passed on to customers.

The three-member commission said in July that it is "seriously considering" eleminating security deposits - an idea that all three utilities, which hold more than 75,000 security deposits in the District, oppose.

The positions of the utilities on provisions proposed in the bill were made public in extensive legal documents filed this week with the PCS Hearings on the matter are scheduled to begin Oct. 4.

The D.C. people's counsel office, which represents consumers in utility matters, also filed a document in the case. Among other things, the people's counsel strongly reommended the elimination of security deposits.

The document said the people's counsel receives many complaints from customers concerning "arbitrary action by the utility in levying a deposit and the excessive amount of the deposit required."

It quoted an officer of a Massachusetts electric company that eliminated security deposits as saying, "We were better off without (them)" because of reduced clerical and other expenses.

Deterrence of defaults on payments is an "illusory objective" of security deposits, the People's Counsel argued. Companies in Michigan and California eliminated deposits without a significant increase in bad debt losses, it said.

The documents filed by the companies disagreed, C & P Telephone Co. said that, of $1.2 million in annual bad debts it experiences among residential customers, "a disproportionately high level . . . is generated by . . . accounts which were secured by deposits." Thus the expense that would ultimately have been borne by the rest of C&P's customers was reduced, the company argued.

Washington Gas Light Co. said the loss of deposits applied to uncollectionually. And Potomac Electric Power Co. said the proposed rules would "impose the burden of increased rates on the customers who do pay."

Pepco also critized the proposed procedures for handling complaints as so "highly structured" that they would "produce costly new intermediate layers of decision-making, delay final resolution of customer disputes, and disrupt credit practices and cash flow."

C&P called the proposed complaint procedures "rigid and mandatory." In a more general comment, the gas company said that its current procedures already "reasonably protect the interests of the vast majority of its custom- ers . . . [There is nothing] to warrant adoption of the costly, complex and legalistic changes incorporated in the . . . proposal."

The people's counsel office expressed concern that any new procedures of handling complains should be simple enough for customers to understand and should not unnecessarily encourage an adversary atmosphere.

"Among the deep concerns expressed by consumers is the all-encompassing one of being able to understand utility bills, regulations and even existing consumer rights," said the people's counsel document.

In arguing that proposed changes would cost the company $1.5 million a year that would have to be passed on to customers, C&P said, "There is no evidence or findings to indicate. C&P's current practices are unreasonable, unjust or discriminatory . . ." Thus the new rules "may constitute an unwarranted infringement upon CP's right to manage its business," it said.

WGL estimated the proposed rules would cost $5.3 million a year to implement, including: $394,500 a year to mail additional meter-reading cards to custoemrs; $4.1 million a year to relocate meters outside for easier reading; $280,000 a year to cut down on the number of estimated bills; $52,700 annually to extend the period before service could be shut off; and $257,500 to make additional required personal contacts with customers.

Pepco was not able to provide yesterday an estimated total cost for implementing the provisions of the proposed bill, but a company spokesman said an estimate would be ready in time for the hearing next week.

Charles Warfield, chairman of the D.C. Consumer's Utility Board, also filed a statement in the case arguing that company policies should be unified "so that customers won't be confused by differing regulations and so that the companies cannot arbitrarily decide how they are going to deal with their customers." The board is a federally funded organization that seeks ways to "restructure overall electricity demand in the city to meet . . . needs through load management and conservation rather than through very expensive new (geneating) plants."