Georgia is raising the amount of allowable chlorophyll-a on Lake Lanier, a move that hasn’t stirred much dissent among lake and environmental groups. The Department of Natural Resources board voted Tuesday to agree with the Environmental Protection Division’s proposal to raise the amount of allowable chlorophyll-a in testing samples to 6 parts per billion from 5 parts per billion at its Flowery Branch testing site and 7 parts per billion from 5 parts per billion at its Browns Bridge Road site. “These are some of the most stringent and lowest levels of any lake in the state ... so it’s already at an extremely healthy level,” said Philip A. Wilheit Jr., Gainesville resident and an at-large member on the DNR board.