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Mr. Tom Schreiner May 25, 2005 Page 7 A memorandum attached to the MMRR Quarry Adequacy Review Response (from Mr. Mike McDemtid, Consulting Civil and Water Resources Engineering, LLC, to Mr. Alex Schatz, Banks and Gesso) documents changes to the original application information. The memorandum claims "sedimentation ponds will be constructed to contain the volume ofrunofPresulting from a 10-yeaz 24 hour precipitation event. The spillway for temporary ponds will be sized to pass flows from the 10- year 24 hour precipitation event and spillways for permanent ponds the 100-year 24 hour event " (Page 4). Also on page 4, the memorandum describes a staging area sedimentation pond as permanent. in addition, a statement on page 13 of the Response to Adequacy Review, "A permanent sedimentation basin, referenced as Sediment Pond C in the initial drawings and the DMG adequacy review letter, has been removed from the reclamation plan" is inconsistent with the Revised Exhibit C-2C which shows the permanent Sediment Pond C. Comment: MLRB Rule §6.3.12 states "where the mining operation will adversely affect the stability of any significant, valuable and permanent man-made structure located within 200 feet of the affected land, the applicant shall either: (a) provide a notary agreement between the Applicant and the Person(s) having an interest in the structure, that the Applicant is to provide compensation for any damage to the structure; (b) applicant shall provide an appropriate engineering evaluation that such structure will not be damaged by activities occurring at the mine; or (c) where such structure is a utility, the applicant may supply a notarized letter...from the owner(s) of the utility that the mining and reclamation activities, as proposed, will have `no negative effect' on their utility". Based on • Exhibit C-2B, the access road will be constructed within 200 feet of aBHCCSD's sanitary sewer line serving the convenience store, yet the applicant has provided no documentation it has complied with MLRB Rule §6.3.12. The runoffmanagement plan must be consistent with water quality discharge permit requirements (MLRB Rules, §6.4.7(c)). As noted above, the applicant will be required to obtain a CDPS Discharge Permit for both process water (which includes runoff from all mitvng and processing areas) and stonnwater. The CDPS general permit includes numeric discharge limits for pH, total suspended solids, and oil & grease for all process water for the Mineral Mining and Processing Point Source Category (40 CFR Part 436), which includes construction sand and gravel. It is important to note that any stormwater runoff that mixes with process water will be subject to the more stringent process water limitations. The Rules also require compliance with applicable water quality standards (MLRB Rules, §3.1.6(b)). It is uncleaz if the ponds aze designed and sized to adequately handle sediment accumulations over the life of the mine. In addition, it is unclear if the ponds are designed and sized to prevent siltation and blockage of the existing Highway 119 culvert immediately downstream. The MLRB Rule § 1.4.1(3) states "all information in an application must be accurate and complete". Exhibit C-2B of the application is not accurate or complete. For example: • It is unclear if one or more of the sedimentation ponds is permanent. If any ponds are permanent, the construction design calculations do not appear to address 100-year 24 hour precipitation events. LEONARD RICE ENGINEERS. INC.