BROADALBIN — There’s a movement afoot to keep a plot of land on the the Great Sacandaga Lake shoreline sandy.Hotel Broadalbin operator Brittani Thompson, within a week, has collected more than 650 signatures and counting on an online petition against Department of Environmental Conservation plans to plant over the 60-year-old-plus Broadalbin Beach. DEC's public comment period is slated to end Feb. 16."As you can tell, I'm obviously like a family-oriented person," said Thompson, tending to a vocal child in the background of a phone interview. “And any space that can welcome families, especially local families, is so important to hold on to and kind…