The power of county governments to control new commercial and industrial developments within their borders was strengthened last week when Maryland Attorney General Francis B. Burch ruled that all large industrial wastewater treatment plants must gain county approval before they can obtain the required permits from state agencies.

In effect, the ruling gives developers of such projects as shopping centers or industrial parks one more hurdle to clear, if their project its to be attached to a private wastewater treatment plant capable of treating more than 5,000 gallons of waste daily.

Burch's ruling, which was co-authored by Assistant Attorney General Warren K. Rich, came in response to a query from Montgomery County officials, who had been seeking to prevent a Silver Spring industrial park from discharging up to 15,000 gallons of photographic wastewater daily into a stream that flows into Paint Branch.

"We have felt traditionally that we've always had the power which the opinion gives us," explained David Sobers, Director of the County's Office of Environmental Planning.

"But now the state has come back and said, 'You're right," he added.

However, Peter S. Tinsley of the Maryland Water Resources Administration said other counties "had been interpreting (the law) in various ways." The intent of the attorney general's opinion, therefore, was to make the application of the law uniform in the state's 23 counties, he said.

The newly clarified regulation for larger industrial and commercial wastewater treatment plant makes the approvals process they must undergo virtually the same as the approvals process already required for private plants designed to treat residential sewage, Tinsley said.

Under this process, developers who want to build industrial or commercial plants which would treat more than 5,000 gallons daily - the equivalent of the discharge from 12 homes - would first have to ask the county to include their plant in the county's main water resource plan, called the 10-year Water and Sewer Plan.

Only after the county had accepted the proposed plant could the developer then get from the State Water Resources Administration and the state Health Department the other permits required under state law.

Up until now, in several insances, the state had issued discharge permits to some proposed industrial and commercial plants, who capacities exceeded 5,000 gallons daily, without waiting for the county to amend its water and sewer plan to include the proposed plant.

The effect of the newly clarified regulation on the state's industrial and commercial developers will vary, "depending on how the individual counties want to approach it," Tinsley said.

"If a county considers industrial development a necessary and desired part of the county's growth, they will probably do everything they can to help," and the approvals process would move swiftly, Tinsley said.

But, "if the county didn't want a project, they could kill it by delay," Tinsley said. And Montgomery County's David Sobers said, "Or they could kill it by not approving it."

Under the newly clarified regulation, "if the counties decided to interpret it strictly, the delays could be tremendous," Tinsleysaid.

The impact of the ruling on the fight between Montgomery County and Colorfax, the Silver Spring photo processing lab to which the state last spring gave a permit to discharge 15,000 gallons of wastewater daily into the Paint Branch system, is not clear.

Charles Dalrymple, attorney for Colorfax, said last week that the ruling did not affect his position, since he was sure that his client would not ask to discharge more than 5,000 gallons daily, - despite the allowance in the discharge permit.

Therefore, Dalrymple said, Colorfax would not have to ask Montgomery County to include this discharge in the 10-Year Water and Sewer Plan.

Sobers, however, disagreed, saying that if the plant had the potential to discharge up to 15,000 gallons, it should be under the same requirements as a plant that intended to discharge that amount.