Shaker Place on Ayer Road will soon be one step closer to expanding its Acton Medical site, backed by the Board of Health at its March 23 meeting.

The health board agreed to send a letter to the Department of Environmental Protection [DEP] supporting Gary Watjus, principal of Jill Realty Trust, in his position that septic water flows at the building are consistently well below the system’s limits. While more discussion will be necessary to approve final septic plans, the board also agreed to notify Building Inspector Gabe Vellante that it had reviewed water flows, approved them, and will wait for the last word from DEP.

According to Watjus’ consulting engineer, Gary Shepard of Ross Associates, renovations are necessary because Acton Medical wants to expand into part of the building formerly occupied by another tenant, adding space for a fourth doctor and a lab room. He explained that the proposed changes should not affect the septic flows.

All lab testing is done in Acton, he said, and the present sink is used only for hand-washing. Additionally, he explained, there are no X-ray machines on the premises, which normally produce small amounts of liquid waste. The required Title 5 septic flow capacity for doctors’ offices is 250 gallons per day, which, he explained, far exceeds actual use. Shaker Place recently passed the latest Title 5 inspection on its septic system, and the owners are able to produce reports that document lower actual flow rates than permitted. This data can typically allow an applicant to bypass normal regulations that are based on hypothetical higher flows.

But Ira Grossman, sanitarian with the Nashoba Associated Boards of Health, advised the board that “the code is specific: If there is a change in use, it has to be in specific compliance with present codes,” which require, for one thing, a two-compartment septic system, which the facility lacks. He acknowledged that he had no objection based on the water readings. Chairman Tom Philippou said the board would okay the renovations if Watjus agrees to install a two-compartment tank, not use X-ray machines on the site, and provide quarterly reports on the water readings.