SWAMPSCOTT-Environmental and public health advocates often point to smoke stacks as easily-identifiable sources of pollution, but such observations typically lack scientific evidence.That could soon change on the North Shore because the Swampscott-based advocacy group HealthLink is sending a group of its members to a so-called smoke school.Lynn Nadeau of Marblehead, treasurer and member of the HealthLink Board of Directors, said the organization plans to enroll a special team who will learn to better recognize smoke stack emissions.”As the North Shore’s most active environmental group, we will send a team of observes to a three-day Visible Emission Training and Certificate program in Boston, conducted by Eastern Technical Associates, a nationally-recognized leader in smoke opacity services and field training,” she said.HealthLink Executive Director Martha Dansdill said the organization frequently fields phone calls from neighbors regarding what they describe as bellowing plumes of dark smoke spewing from the stacks of the Salem Harbor Station electricity generation plant on the Salem waterfront.”Others send photos of unusual emissions from the stacks,” she said. “By having a team that is certified to recognize smoke opacity violations and who will monitor the stacks on a daily basis, we will be able to record and report violations to the Department of Environmental Protection in a timely fashion and with authority.”According to Dansdill, the aging power plant recently came under scrutiny of both the Massachusetts Department of Safety and the federal Occupational Safety and Health Administration.Following the November 2007 explosion at the Salem plant that killed three employees, the certificates of inspection for the facility’s four boilers were temporarily revoked. State inspectors said the explosion was caused by neglect of routine maintenance over a 10-year period as well as improper, unsafe operating practices.”The owner of the power plant (Virginia-based Dominion) has a track record of ignoring regulations and safety at the plant,” Dansdill alleged. “We will continue to monitor their activities from the outside.”The opacity training school will be partially funded by a $1,200 grant HealthLink received from the New England Grassroots Environmental Fund. Applicants interested in the training should contact HealthLink at [email protected] or call 781-598-1115.