REVERE – The architect designing the city?s new middle school has spent $500,000 on soil work and drainage at the school site to avoid the foundation problems plaguing Lynn?s newest high school.The requests helped contribute to a 65 percent rise in design costs for Rumney Marsh Academy. City Council members criticized the increase last month and sought to block additional city expenditures on the Rumney design.But chief project spokesman Jeffery Luxenberg informed Mayor Thomas Ambrosino by letter before Monday?s council meeting that more than half the design cost increase represents expenses associated with flood control and soil stability.Like Lynn?s Classical High School, Rumney Marsh is being built on a site where contaminated soil has been found. But Revere is trying to avoid the foundation preparation problems that caused the concrete slab Classical was built on to settle. Lynn is spending millions of dollars to undertake significant repairs and foundation support work. Rumney Marsh?s architect wants to hire engineers to make sure, in Luxenberg?s words to Ambrosino, “all structures are constructed on solid foundations.”Contaminated soil condition on the construction site next to Revere High School prompted project manager RF Walsh to build a deep pile foundation for Rumney Marsh.The Classical High builders used a method called “deep dynamic compaction” to compress tons of soil mixed with decades? worth of solid-waste landfill debris. Designers of the city?s new police station specified a “geo pier” foundation design to ensure a stable foundation for the 32,000 square foot station.Geo pier involves filling holes pored into the ground with gravel that is tightly compacted to form foundation support columns.Walsh has also overseen the project architect?s design of an extensive new drainage system. Luxenberg told the mayor the system will “help relieve the school site and the neighborhood of severe flooding during major storms.”