ERIN – The council chamber here was packed on May 14 with residents opposed to the remediation plan for the Hillsburgh gravel pit.Among them were delegates from the Erin Citizens Coalition, formerly the Concerned Citizens of Erin, which spearheaded opposition to the project. Erin council approved the remediation plan in January for the property at 9516 Sideroad 27. The site operated as a sand and gravel pit for Strada Aggregates from 1999 to 202…