MARBLEHEAD – The Conservation Commission has the required paperwork for a 20-unit condominium development at 151 Green St. and is looking to hire an expert to examine it before a decision is made.The commission hearing on the proposal, which began in September, has been continued to its next meeting Jan. 12, one week after the deadline commission Chairman Walter Haug has tentatively put on the request for proposals from wetlands consultants."I hope that’s realistic," Haug said Monday evening. "This is a large project really, and we have a responsibility to a lot of abutters regarding drainage."Attorney Paul Lynch, who represents owner John Muldoon of Green Street Realty Trust, went over a list of needed documents submitted by the Department of Environmental Protection Thursday evening and confirmed the submissions.Lynch said his wetland expert, Brad Holmes, discussed the list with the DEP. The developer’s Sept. 28 storm water management or drainage report was revised Nov. 25 to bring it in line with DEP requirements. Among the other documents and information was a wetland replication report, which shows how the developer plans to restore any wetlands affected by the project.Lynch said Holmes followed up with the DEP, asking if any further information was needed, and had not received any further calls.Haug told him the commission would seek bids from peer review specialists.As of two months ago, following a site visit, Haug said commission approval of the project looked "promising," but the DEP called the Notice of Intent (NOI) "incomplete" and said the project required much larger storm water sediment collection apparatus.The Green Street development is the first to use a 1990s incentive zoning bylaw. It will contain 20 two-bedroom condominium units in 10 structures at Green Street and West Shore Drive, seven on the street and three at the back of the lot, close to a marshy area. Two units will be affordable. The Planning Board has placed its hearing on the project on hold until the commission finishes its hearing. That hearing began in April and the board held off to get the commission’s input on drainage issues at the site.