Item 1: PH on Ordinance Amending Metro Plan (Delta Sand and Gravel)

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In response to a question from Ms. Nichols regarding when the excavation was finished and refilled and if there would be impacts to nearby homeowners, Ms. Kupillas said that was a problem that had not been addressed by the applicant. She said refilling the area, depending on the fill material, could cause additional problems. She said the applicant's report did not talk about the impacts of the low permeability barrier and opined that this was essentially mining in an area where no mining should be allowed. She noted that the top of the barrier would be 130 feet .wide and 12 feet at the bottom. In response to a question from Ms. Arkin regarding' how deep the barrier would be, Ms. Kupillas said the applicant had proposed a depth of 30 feet. In response to a question from Ms. Arkin regarding whether it was possible that the water would. flow beneath the barrier, Ms. Kupillas said the reality was that the barrier was only partial and was really just slowing down water flow. She said water would still be.able to flow in the older alluvium below the barrier. She said there were wells that could produce up to 100 gallons per minute from those lower gravels. She said water would still be flowing into the pit and the applicant was expecting water to be coming through. . Mr. Zdzienicki commented that originally the applicant was proposing a 30 foot depth with an excavation to 60 feet. He remarked on the 30 foot discrepancy. In response to a question from Mr. Zdzienicki regarding whether the Silver Meadows housing development was located on topsoil on top of gravel, Ms. Kupillas said she was not familiar with the specific development. In response to a question from Mr. Zdzienicki regarding whether the area just to the west of the housing development had gravel as well, Ms. Kupillas said it was. Mr. Zdzienicki questioned whether, if the excavation for low permeability barrier would go 30 feet below the barrier, the ground water in the development to the west be slowly drained away with the land drying out and vegetation being impacted as a result. Ms. Kupillas said that was possible. She said the current water levels were lower than they should be because of the current activities of Delta Sand and Gravel. She said Delta was trying to install a low permeability barrier to . have less of an effect on the ground water level. She said the applicant was hoping that 'less of an effect' would mean ground water rising to previous levels. She said the problem with that assumption was that there would still be water flowing into the excavation. She said if water levels outside of the barrier built up it could create more pressure for the water to go lower and come out beneath the low permeability barrier. In response to a question from Mr. Dignam regarding what would happen if the water did flow through or under the barrier, Ms. Kupillas said nearby domestic wells and irrigation wells could go dry. In response to a'question from Mr. Dignam regarding whether it was her contention that the low permeability barrier would lower ground water levels while still being a risk of flooding to nearby housing, Ms. Kupillas there was a possibility of negative impacts whichever way the water went. Mr. Dignam commented that. he was uncertain how the low permeability barrier could both c~use flooding,and cause wells to go dry. MINUTES-Lane:County Planning Commission. . Eugene Planning Commission .January 17, 2006 12