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HomeMy WebLinkAboutTRANSMITTAL OF RESPONSE AND RECLAMATION PLAN AND SUPPORTING DOCUMENTS (MIN 96-03)Butte County Department of Development Services TIM SNELLINGS, DIRECTOR I PETE CALARCO, ASSISTANT DIRECTOR 7 County Center Drive Oroville,.CA 95965 (530) 538-7601.Telephone (530)538-7785 Facsimile ADMINISTRATION " BUILDING * PLANNING October 2, 2006 Mr. James S. Pompy 801 K Street, MS 09-06 Sacramento, CA 95814 RE: Transmittal of Response and Reclamation Plan and Supporting Documents M&T Chico Ranch Mine Reclamation Plan (MIN 96-03) Dear Mr. Pompy: Enclosed please find a Revised Reclamation Plan and materials provided by the applicant, Baldwin Contracting Company.* This material includes a letter dated September 20, 2004, along with a bound document entitled "Reclamation" Plan and Supporting Documents" that together responds to the Office of Mine Reclamation letter of June 10, 2004 (included in the attached). Where revisions were not necessary to the Reclamation Plan comments within the Baldwin letter provide explanations orreferences to supporting materials .that address the comment. The Butte County Department of Development Services' finds that the amended Reclamation Plan, including the responses provided by the applicant (Baldwin Contracting Company, Inc.), address the comments provided in your letter of June 10, 2004. This Reclamation Plan is in compliance with the applicable requirements of Article I (commencing with Section 3500) of Chapter 8 of Division 2 of Title 14 of the California Code of Regulations. Si rel Dan Breedon Principal Planner Enclosure cc: Chuck Thistlethwaite, Planning Manager Pete Calarco, Assistant Director of Development Services BALDWIN CONTRACTING COMPANY, INC. GENERAL ENGINEERING CONTRACTORS 1764 SKYWAY / CHICO, CA 95928 (530) 891-6555 (530) 894-6220 FAx Mr. Dan Breedon Principal Planner Butte County Department of Development Services n E CEO U E V SEP 2 3 2004 BUTTE COUNTY PLANNING DIVISION 25 County Center Drive Oroville, CA 95965 RE: Department of Conservation comment letter dated June 10, 2004. Dear Dan, This letter sets forth Baldwin Contracting Company's ("BCC") responses to the Department Lof Conservation's ("DOC") comment letter, dated June 10, 2004. The DOC's letter commented on BCC's reclamation plan for its M & T Ranch mining operation. The Surface Mining and Reclamation Act ("SMARA") requires that prior to approving a surface mining operation, a lead agency submit the reclamation plan and supporting documents to the Director of DOC (delegated to the office -of Mine Reclamation ["OMR"]) for comments. (Cal. Pub. Resources Code § 2774(c).) OMR has 30 days to issue its comments. (Cal. Pub. Resources Code § 2774(d)(1).) The lead agency then must prepare written responses to the issues raised by OMR. The lead agency is not required to resubmit the reclamation plan to OMR for additional comments. (See Cal. Pub. Resources Code § 2774 (c) -(d).). This letter's headings are organized to correlate with the items raised in DOC's June 10, 2004, letter. We have attached a bound version of the reclamation plan with supporting documents, for your convenience. OMR raised the following issues: Paragraph 3• Page 1 OMR states on page one that the utilized reclamation plan format "is not appropriate for a site of this size and complexity." BCC used the reclamation plan format selected by Butte County ("County"). The reclamation plan contains all the necessary requirements set forth is SMARA. The reclamation plan's size and complexity is a reflection of the documents thoroughness and the diligent collaboration between the County and BCC. Enclosed with this letter is a bound copy of the reclamation plan, along with its supporting documents. BCC bate - stamped the pages to make the reclamation planand its supporting documents easier to navigate. Item 1, page 2 OMR states in item one on page 2 that the reclamation plan needs to include "a termination date for the operation" and a discussion of the time frame for reclamation. SMARA section 2772(c)(3) requires reclamation plans to include "proposed dates for. the initiation and termination of surface mining operations." (Emphasis added.) BCC has both a proposed initiation and termination date in its reclamation plan. The "proposed initiation date is the date all permits necessary to initiate operations are approved by the regulatory agencies." The "proposed termination of surface mining operations is 30 years after the proposed initiation date." (Reclamation Plan and Supporting Documents, Attachment 2, bate -stamped page 22, paragraph two.) Item 2, page 2 OMR states in item two on page two the following-. The effects of siltation and the reduction in substrate transmissivity values by deposition of suspended sediment carried in Little Chico Creek during periods of flooding has not been evaluated in terms of the proposed end use of the site as a ground water recharge "lake." The effectiveness of groundwater recharge would be expected to diminish as the ponds silts in. California Code of Regulations, title 14, section 3502(b)(2), cited by OMR, states "[o]perations shall be conducted to substantially prevent siltation of ground -water recharge areas." (Cal. Code Regs., tit. 14, § 3502(b)(2) [emphasis added].) California Code of Regulations, title 14, section 3706(b), also cited by OMR, provides that the "quality of water, recharge potential, and storage capacity of ground water aquifers which are the source of water for domestic, agricultural, or other uses dependent on the water, shall not be diminished, except as allowed in the approved reclamation plan." Siltation will not be an issue at the M & T site. The lake, as designed, will substantially prevent siltation of ground water recharge, and will preserve the quality, recharge potential, and storage capacity of the lake. This is explained in greater detail in the letter written to the County by Steve Deverel of Hydro Focus, Inc. (Reclamation Plan and Supporting Documents, Attachment 18.) -2- Item 3, page 2 OMR states in.item three on page two that "there is no detailed engineered design for the bypass channel or weir structure proposed to mitigate most of the floodplain impacts that would result from the placement of a deep mining pit with 100 feet of Little Chico Creek." California Code of Regulations, title 14, section 3506(e), cited by OMR, states "Where natural drainages are.... impacted by surface mining activities, mitigating alternatives shall be proposed and specifically approved in the reclamation plan to assure that runoff shall not cause increased erosion or sedimentation." BCC's reclamation plan specifically incorporates mitigating alternatives for natural drainages utilized in the M & T environmental impact report ("EIR"). The reclamation plan incorporates the weir and bypass channel mitigations as set forth in Mitigation Measure 4.4-3b and 4.4-7c. (Reclamation Plan and Supporting Documents, Attachment 14.) The weir and bypass channel, as stated in the reclamation plan, will "protect the water in the lake from flood water entry up to the 1.0 year event." The weir and bypass channel will be made conditions of approval for the project. BCC undertook substantial steps in the planning process to ensure that the weir ,and bypass channel would be viable and effective. Design information for both the weir and the bypass channel are contained in Attachment 16 and Attachment 17 to the Reclamation Plan. (Reclamation Plan and Supporting Documents, Attachments 16 and 1.7.) In addition NorthStar Engineering has designed a weir on Butte Creek to take overflow, high water, upstream'of the "Oakie" Dam_ , off Honey Run Road, in Butte County. Item 4, page 2 OMR states in item four on page two that there is no design basis for the increase in buffer width from 50 feet to 100 feet adjacent to Little Chico Creek. And in addition, that "this buffer [100 foot] has not been incorporated in the cross sections or diagrams supplied for the reclamation plan." The buffer for the project was increased from 50 feet to 100 feet as an added mitigation measure during the EIR process. OMR is correct in noting that the previous version of Exhibit 2 did not incorporate the 100 -foot buffer. This was a typographical error. BCC revised Exhibit 2 to the reclamation plan to reflect this change. (Reclamation Plan and Supporting Documents, Attachment 6.) Item 5, page 3 -3- OMR states in item five on ,page three that the mitigation for erosion of the proposed bypass channel is, in part, repair by onsite heavy equipment. OMR states that this mitigation would not be effective after mine closure and removal of the onsite equipment. OMR opines that the "bypass must be designed as a long term solution and have a maintenance agreement in place to perform repairs after site closure." BCC designed the bypass channel as a long-term solution to replace water overflow into the Little Chico Creek distributary. The bypass channel does not require a maintenance agreement after site closure. The bypass channel will be designed to blend into the natural topography of the surrounding area and Little Chico Creek. The reclamation. plan, through the incorporation of EIR mitigation measures, requires that native plant species be utilized in the bypass channel design to control erosion and to provide long-term bank stability, thus making the bypass channel a suitable alternative to the present downstream distributary on a long-term basis. Item 6, page 3 OMR states in item six on page three that "[s]eparation of Little Chico Creek and the lake formed following mining only limits commingling of the two water bodies to a 10 -year flood event...." OMR is concerned that commingling might create the "Potential for movement of warm water prey species out of the lake and down the creek to :the Sacramento River with possible impacts to anadromous fisheries." Little Chico Creek is a warm water creek that could support warm water prey species. The lake is an isolated lake on private property. Warm water prey species will not be stocked in the lake. The only potential for warm water prey species to enter the lake is if Little Chico Creek commingles with the lake via a storm event greater than a 10 -year storm event and warm water prey species enter the lake from Little Chico Creek. In that case, however, any species that enter Sacramento River would have come from Little Chico Creek, not the lake. . Further, in its comment letter on the project, the Department of Fish and Game ("DFG") expressed no concern over warm water prey species in the lake. Item 7, page 3 OMR states in item seven on page three the following: The reclamation plan indicates that revegetation will be attained by natural revegetation except those areas where revegetation is 'insufficient.' .. . Reliance on natural revegetation is not an option under the statewide reclamation standards regulations. Proactive measures to achieve the stated end use must be described in the plan, including a complete description of the number of plants, cuttings and or seed of each species that will be used in the revegetation plan. -4- The performance standards for revegetation are set forth in California Code of Regulations, section 3705. The standards do not ;prevent utilization of natural revegetation. Rather, section 3705 measures success of revegetation "based upon the effectiveness of the vegetation for the approved end use, and by comparing the quantified measures of vegetative cover, density, and species -richness of the reclaimed mined -lands to similar parameters of naturally occurring vegetation in the area." (Cal. Code Regs., tit. 14, § 3705(m).) While sensitive to OMR's concerns, BCC has taken great care to ensure that the current reclamation plan provides for a detailed, exhaustive, and legally supportable revegetation plan. The reclamation plan revegetation standards track the statutory requirements mandated by SMARA and its associated regulations. For example, California Code of Regulations, section 3705(m) states the following: Success of revegetation shall be judged based upon the effectiveness of the vegetation for the approved end use, and by comparing the quantified measures of vegetative cover, density, and species -richness of the reclaimed mined -lands to similar parameters of naturally occurring vegetation in the area. (Cal. Code Regs., tit. 14, § 3705(m).) The M & T Ranch reclamation plan tracks these requirements. The reclamation plan states "Performance standards ... will be evaluated based on the effectiveness of the vegetation for wildlife habitat by comparing appropriate measures of cover, density and species richness of the reclaimed lands to similar parameters on reference areas." In addition, the reclamation plan requires that "[m]ethods for monitoring and assessment will be based on guidelines provided in the Department of Conservation's recently published manual on the rehabilitation process for disturbed lands (Newton and Claassen, 2003)." Item 8, pace 4 OMR states in item eight on page four that the present exhibits do not describe the three plant community locations. OMR also asserts that the reclamation text indicates the nesting island will be in the deepest portion of the lake, but Exhibit 2 shows the nesting island as adjacent to the east shoreline. Following OMR's suggestion, BCC prepared an additional map, Exhibit 3, that shows, among other things, the precise locations of the three plant communities. (Reclamation_Plan and Supporting Documents, Aftachment 7.) The reclamation plan text explains that the nesting island is feasible. Specifically it provides that, even if it were to be to constructed in the middle of the lake, there would be sufficient backfill to create the island. The reclamation plan states as follows: -5- The nesting island will be constructed using excess overburden and silts and clays removed from the aggregate in the processing plant. An estimated 2.5 million cubic yards of... overburden materials and 500,000 cubic yards of fines will be available to construct the nesting island.... A 1 -acre nesting island constructed entirely of fill in the deepest part of the lake would require only about 500,000 cubic yards of material so sufficient excess overburden and fines are available for the reclamation plan. This analysis is.not intended to establish the location of the island. The actual location of the island will be along the eastern shoreline as depicted in Exhibit 2. (Reclamation Plan and Supporting Documents, Attachment 6 and Attachment 7. Item 9, page 4 OMR states in item nine on page four that "the plan needs to contain more detailed information concerning the water fluctuation levels and how this would impact the 'margin habitat."' In addition, OMR states that the "plan does not describe any irregular feature to the shoreline such as peninsulas or bays.... A final map illustrating the modified shoreline needs to be included in the plan and a visual presentation of the 50- foot.wide margin habitat illustrated." BCC is monitoring wells to gather information on future water fluctuations within the lake. As the excavation of the lake progresses, additional and more detailed information on water level fluctuations will be acquired. The revegetation specialist wilt take the water fluctuation data and use it to establish the exact location and scope of the margin habitat. Currently, data has been collected from 2003-2004. This data is included as Attachment 19. (Reclamation Plan and Supporting Documents, Attachment 19.) As mentioned above, BCC created a new map, Exhibit 3, to respond to OMR's comments.. This map includes a depiction of an irregular shoreline, designed to mirror those found in natural environments. (Reclamation Plan and Supporting. Documents, Attachment 7.) Item 10, page 4 OMR states in item 10 on page four that "[c]onstruction of wildlife habitat requires specific revegetation performance standards for each of the three habitats proposed." The reclamation plan contains revegetation performance standards for each of the three habitats proposed, including the emergent zone, the shoreline zone, and the marginal zone. As explained prior,. the reclamation plan states: IN Performance standards for the shallow wetlands [emergent zone species] and lake perimeter [marginal and shoreline zone species] will be evaluated based on the effectiveness of the vegetation for wildlife habitat by comparing appropriate measures of cover, density and species richness of the reclaimed lands to similar parameters on reference areas. To make this point even more clear, these species can be observed on Exhibit 3 to the reclamation ,plan, which is attached as Attachment 7 to the reclamation plan. (Reclamation Plan and Supporting Documents, Attachment 7.) Item 11, page 5 OMR states in item 11 on page five that the reclamation plan fails to describe revegetation monitoring. Specifically, OMR claims the following: The plan does mention that revegetation will be monitored for five years but the plan fails to link monitoring to performance standards.... The plan must state that revegetation will be monitored annually in the spring by a qualified botanist or restoration ecologist for a minimum of five years following planting. A description of the monitoring plan must include a discussion of the statistical sampling method for determining revegetationr success. The sampling method must provide at a minimum an 80% confidence level that the portion of the revegetation sampled represents the revegetation of the site as a whole. BCC has taken great steps to ensure that its revegetation plan either meets or exceeds all monitoring requirements set forth in SMARA and its regulations. The reclamation plan specifically provides that revegetation monitoring will take place for five years. During the five-year monitoring period, annual reports will be submitted to the Bufte County Planning Division. The reports will describe the success of the, revegetation plan and will include recommendations for how to improve, if possible, the plan's success in the following year. In addition, the reclamation plan expressly provides. as follows: Methods for monitoring and assessment will be based on guidelines provided in the Department of Conservation's recently published manual on the rehabilitation process for disturbed lands (Newton and Claassen, 2003). In other words, the reclamation plan is designed to mirror SMARA's revegetation requirements. Item 12, page 5 OMR states in item 12 on page five, that the reclamation plan must have a signed statement of responsibility. -7- The reclamation'-plan has a signed statement of responsibility. BCC carefully considered OMB's comments in preparing this letter. While many of the comments were already addressed in the reclamation plan, some positive minor changes were made as a result of OMR's comments. Please call me at your earliest convenience to discuss this letter and to set up a meeting to establish a timeline to approve the reclamation plan. Sincerely, Rene A. Vercruyssen cc: Jeffrey K. Dorso, Esq. , The Diepenbrock Law Firm K / I y .8. NorthStar ENGINEERING Civil Engineers • Surveyors October 19, 2005 Rene Vercrussen Baldwin Contracting Company, Inc 1764 Skyway . Chico, CA 95828 RE: Public. Works Comments 6-22-05 - M&T Chico Ranch Mine Dear Rene; This letter is in response to the comments received on 6-22-05 from the Department of Public Works. Their comments were limited to concerns involving drainage and flood control aspects of the "Reclamation Plan and Supporting Documents for M&T Chico Ranch Mine; dated September 2004". A large number of their comments are in regards to supporting documents in the plan, many of which are from the original Environmental Impact Report (EIR) dated September 2002. It should be noted that the County has already reviewed and commented on the EIR. The intent of submitting this to the county was not a second review of the EIR but a review of the supporting material that has been asked for by various agencies. J We realize that the County is an important party in the review and approval process, but at the same time we would like the county to understand that they are but one of many agencies that are reviewing and approving the project. Many of these agency's "area of concern" overlap and may not directly agree, because of this we are seeking the counties help in coming to compromises with the other agencies involved. Please read through the responses to the Public Works comments and keep in mind that at this stage of the proposed project only approval of the project concept and EIR is being proposed, not specific engineering plans for construction. There will be more than adequate time to review engineering plans and file for permits after the EIR approval. Si cerel , Ross Simmons, P.E. NorthStar Engineering 20 DECLARATION DRIVE CHICO, CALIFORNIA 95973 530-893-1600 FAX -893-2113 The comments from the 6-22-05 Public Work's review are shown in italics and responses to comments follow. 1. The weir and bypass channel locations shown in attachment 6' disagree with the mitigations in attachment 14 and designs in attachments 16 and 17. Response: Attachment 6 has been revised to clear up mis- understandings and discrepancies. .One major point of confusion is that there are 2 separate bypass channels with 2 separate purposes mentioned in the EIR. The bypass channel described in 4.4-3b is along the western side of the pit and is to be designed to accept flows from Little Chico Creek that historically went through the pit location. Its purpose is to alleviate the impacts of the low levee/weir on the Jones parcel by mimicking the current splitting of Little Chico Creek. Attachment 16 demonstrates a possible design for this bypass channel. One of two options for mitigating closures on River Road due to flood waters is removing an existing levee and constructing a setback levee. The other.option includes installing larger culverts and raising the road at the low points in River Road. The second bypass channel mentioned in the text (MM 4.4-7a) is in reference to the setback levee. The existing levee just west of the proposed plant site could be removed and a new. levee (not to exceed the original's elevation) could be constructed 200' to the east of the old levee. In a 1-17-02'preliminary report by NorthStar Engineering one mitigation measure .was to construct a set back levee, leave the existing levee intact, and construct a bypass channel between the levees. This bypass . channel would convey flood waters that overtopped the existing levee to enlarged culverts at the south edge of the plant and back into Little Chico Creek. A report was issued on 2-27-02 that suggested (as one mitigation option) the existing levee be removed completely allowing flooding waters complete access to the area and thus negating the purpose of the bypass channel. Attachment 6 shows this mitigation measure. Attachment 17 is a possible design for the low levee/weir described in the EIR and matches schematically what is shown on Attachment 6. Attachment 6 has been revised to match the wording used in the' EIR and attachment 17. 2. Attachment 14, mitigation measure (MM) 4.4-3a indicates that the storm water from the processing plant will not enter the pit but does 1 not disclose where or how the storm water will be handled.. Impact 4.4-4 indicates "Internally generated storm water will be retained on-site", then indicates a permit will be required to allow this water to go off-site. The plan needs to define and analyze what is actually proposed either on-site, retention or on-site detention with drainage to a natural water course? Response: It is correct that storm waters will be kept from entering the pit, this includes existing field ditches 'to the east and south of the pit as described in MM 4.4-3c as well as storm water from the plant site in MM 4.4-3a. The purpose of keeping field runoff and plant runoff from entering the pit up to a 10 year event, is to minimize any possible impacts to groundwater. It is recognized that runoff from farmed fields can contain high levels of pollutants, that in high concentrations can. jeopardize ground water safety. What the statement in MM 4.4-3a is saying is that storm waters from the plant SHALL NOT enter the pit. The statement in 4.4-4 then elaborates on where these waters CAN go, which is back into Little Chico Creek (with the proper permitting). These permits would include a basic site development plan with the County of Butte. Included in this would be pre and post storm water runoff estimates and likely (as required by the County) a no net increase in peak runoff requirement. When a construction permit is applied for a detention pond can be sized and included in the southwest corner of the proposed plant area. The entire plant facility would be tributary to this detention pond and flows released to Little Chico Creek would be less than the pre -development flows. 3. Attachment 14, MM 4.4-3b, how will floodwater be drained from the pit? See the second paragraph on page 243 "As a worst case, in theory, overflows could erode down the buffer and Little Chico Creek could be diverted, in its entirety, through the created lake." -How will the pit and subsequent reclaimed lake be operated and maintained to protect the existing Little Chico Creek? Response: In the 10+ year event it is recognized that Little Chico Creek will spill over the weir and enter the pit. This will raise the lake water level up to a point where the lake will spill out of the south end and back into Little Chico Creek. This flow path currently exists now at the proposed location of the weir. As the 10 year flood recedes tale water level in the pit will steadily drop to the bottom of the existing channel out, then slowly drop to its base level through steady infiltration to the creek bed and aquifer. There will be no need to "drain" the pit entirely as it is proposed to be wet mine. The "worst case scenario" depicted on page 243 is mitigated in both MM 4.4-5 and MM 4.4-6.. The mitigation measures state that the slope of the buffer shall be designed by a registered civil engineer to prevent erosion, approval of the plan by Butte County is required. Both structural and vegetative measures shall be used to stabilize the buffer strip (pg. 4.4-70 of the EIR). Note that originally a 50' wide buffer between the top bank of Little Chico Creek and the pit edge was proposed but this has been increased to 100'. 4. Attachment 14, MM 4.4-3c, the channels to be improved and proposed improvements need to be shown on the plans and fully addressed in the text. It is unclear whether ditches within 1, 000 feet on the east side or ditches on the east side to 1, 000 feet southerly (no plan view associated with text) are proposed to be improved to a 10 -year capacity. No design calculations or plans were provided for these ditches. The flood impact studies by NorthStar Engineering do not show the boundaries of the 10 -year event, however the FEMA mapping indicates the 100 -year flood plain :extends more than 1, 000 feet east of the mine site and includes the topsoil stockpile areas. What is the purpose of improving the ditches on the east side to a 10 year design capacity? Provide analysis for the impacts of the topsoil stockpiles to the flood plain elevations. Also this MM identifies the fact that all the proposed' levees will be overtopped by flood flows from the Sacramento River, but does not identify erosion control measures to be taken to protect the levees and pit slopes during operation or to provide protection for the reclaimed lake. Response: The ditches in question have been added to attachment 6 to help clarify the wording in the EIR. The existing ditches are to include the ditch at the southern edge. of the pit as well as all existing ditches within 1,000 feet of the eastern side of the pit. The ditches carry local storm water from the fields to the north and east and do not carry flows from Little Chico Creek. The purpose of ensuring these ditches will accommodate' the 10 year design flows is to keep the direct field runoff from overflowing the ditches and entering the pit. _ The 10- year flood in Little Chico Creek does not enter the pit area staying instead to the west of the pit (in the bypass channel and in Little Chico Creek through the Jones parcel): The topsoil piles are to the west 3 of the pit beyond a levee and do not effect the 10 -yr flood plan elevation. The 100 year flood plain topic is covered on page 4.4-6 of the EIR. 5. Attachment 14, pages 243 and 244, proposed project with and without batch plant identifies a 50 foot not 100 foot wide buffer between Little Chico Creek and the northern edge of the pit. This conflicts with other information contained in the document, including attachment 6. Response: This is correct. The EIR continually references a 50' buffer, however this has been increased this to 100'. 6. Attachment 14, it appears pages are missing from the document so v a complete evaluation cannot be made. Page 244 is identified as 4.4-73,'page 245 is identified as 4.4-75.and the content does not flow from one page to the .next. Also page 245 (the last page of this attachment) ends in the middle of a sentence. Provide a complete, comprehensive copy of this attachment for review and comment. Response: This is correct. The document provided for review was a compilation of relevant Reclamation Plan documents, titled "Reclamation, Plan and Supporting Documents". 'To give context to the discussions the document contains some excerpts from the EIR, BUT does not include the complete EIR. This document is intended to support and be read with the EIR. Attention is drawn to the fact that the pages mentioned above have the words "M&T Chico Ranch Draft EIR" written next the EIR page number and then followed by a bold single page #. The attempt was not to' confuse the county but to provide clarity by organizing all the supporting documentation in one place. 7. Attachment 16 provides some design calculations for a Little Chico Creek bypass channel, but does not provide information with respect to the construction location or design flow of 1, 000 cfs. Response: Attachment 16 is difficult to understand out of context.' What it is attempting to show is that. a sufficient bypass channel can be designed to mitigate the flooding of the Jones tract which would occur once the low levee/weir was installed. The bypass channel would be designed to mimic the existing flow event through the pit area. This existing flow occurs when the. Little Chico Creek flows top 300 cfs. Once the project is approved detailed plans for the bypass channel and its head works will be developed and submitted to the county for review and approval. 0 8. Attachment 17 provides a design for an overflow weir for Little Chico Creek, but does not provide a backwater analysis for the flood plain and does not address how Sacramento River overflows will react to the weir and setback levee. The design appears to be for the 50 year event, not the base flood, 100 -year event. Page 304 profile, is the left levee looking upstream or downstream. Sections 1, 2, and . 2.5 appear to intersect the pit, but there is no information with respect to the sections looking upstream or downstream and the pit is not shown. Response: Attachment 17 does contain a backwater analysis for the flood plain. The report analyzes the water surface elevation from cross section 8 to section 0.5 as shown on page 300. The addition of flows from the Sacramento River complicates the area and makes a dependable hydraulic analysis extremely difficult; this is why no 100 yr flooding is shown." It should be noted that the detailed study area with 100 year water surface elevations prepared by FEMA ended just upstream from the Sacramento River sloughs and the project area. The 100 year flood plain topic is further covered on page 4.4-6 of the EIR. Note that.all HEC RAS model river stations are viewed from the path of flow meaning you start at the upper most and view them traveling downstream.'.This makes the "left levee" the same as the east levee for this study. The pit is not shown on the cross sections; but flow through the pit equals. that over the weir. 5 _ _ BALDWIN CONTRACTING COMPANY, INC. GENERAL ENGINEERING CONTRACTORSs�t ��CTINGC�' 1764 SKYWAY/CHICO, CA 95928 (530) 891-6555 (530) 894-6220 FAX _ NOV V.1 DEVELOPN"I - SERVICES October 18, 2005 Butte County -, Department of Development Services Attention: Dan Breedon 7 County Center Drive Oroville, CA 95965 Re: M&T Ranch Mine, Butte County Department of Public Works (DPW) comments on Reclamation Plan and Supporting Documents, submitted on September 20, 2004, by Baldwin Contracting Company, Inc. " Dear Dan: _ On September 20, 2004, Baldwin Contracting Company, Inc. (Baldwin) submitted a letter - and a document titled, Reclamation Plan and Supporting Documents, in reply to Department of Conservation (DOC) letter of comment dated June 10, 2004. As most of the questions contained in the DOC letter had already been addressed in other documents, Baldwin was concerned that there was some confusion among the agencies with review authority about _ the reclamation plan for the M&T Ranch Mine project. For that reason Baldwin used the time between June and September of 2004 to compile a document, made up entirely of documents already submitted and reviewed by state and county agencies, that was intended to provide the agencies a comprehensive compilation of the reclamation plan and portions of other documents referenced in the reclamation plan in one place. Over ten months later, on August 2, 2005, Baldwin received a letter from Butte County Development Services, with an Inter -Departmental Memo from the Public Works Department, dated June 22, 2005. This memo had eight numbered comments, regarding "drainage and flood control aspects of the Reclamation Plan and Supporting Documents for M&T. Chico Ranch Mine". Many of the DPW comments were on excerpts from the Draft EIR prepared for the M&T Ranch Mine - Project in September 2002, and already commented upon on several occasions by the state and county agencies. The Draft EIR was extensively excerpted in compiling the Reclamation Plan and Supporting Documents. Baldwin submitted the DPW comments to NorthStar Engineering, who did the flood study work for the Draft EK for reply: Attached is a cover letter and replies from NorthStar Engineering. - Very truly Yours David Barney President Baldwin Contracting Company, Inc. Butte County Department of.Development Services UT T PAUL MCINTOSH, INTERIM DIRECTOR o� Fo. 7 County Center Drive o 0 Oroville, CA 95965 0 0 (530) 538.7601 Telephone o (530) 538.7785 Facsimile o- o, COU IN ADMINISTRATION * BUILDING * GIS * PLANNING August 2, 2005 ; Mr. Rene A. Vercruyssen Baldwin Contracting Company, Inc. 1764 Skyway Chico, CA 95928 RE:, Department of Public Work's,Review of "Reclamation_ Plan and Supporting Documents for M&T Chico Ranch -Mine, September 2004" Dear Mr. Vercruyssen: Enclosed please find. comments received from the Butte County'Department of Public . Works concerning the September 20, 2004 submittal 'referenced above. Prior to transmitting this document to the Department of Conservation, *the comments provided,by the Department of PublicWorks must be addressed. Please provide a response to the issues brought forward by the Department of Public Works in the attached June 22„2005 memo. This response must be received prior to scheduling this project before the Planning Commission: This project has been continued' off the Planning Commission Agenda, 'due to the Williamson Act Contract, cancellation. and non -renewal process that has been under consideration by your company. Therefore I am not sure when this project will again be scheduled fora Planning Commission hearing. Thank you for your attention to this matter. Should you have any questions, please contact me at this office. ye1 Dan Breedon Principal Planner Enclosure Y INTER -DEPARTMENTAL MEMORANDUM PUBLIC WORKS DEPARTMENT TO: DAN BREEDON, PRINCIPLE PLANNER. o.�V.T, O: 0 i - 0 0' U N� A�Crc. wOP�y �+ FROM: STUART EDELL, MANAGER, LAND DEVELOPMENT DIVISION PUBLIC WORKS , SUBJECT: RECLAMATION PLAN AND SUPPORTING DOCUMENTS FOR M&T CHICO RANCH MINE DATE: JUNE 22, 2005 We have the following comments with respect to drainage and flood control aspects of the "Reclamation Plan and Supporting Documents for M&T Chico Ranch Mine, dated September 2004": 1. The weir and'bypass channel locations shown in attachment 6 disagree with the mitigations in attachment 14 and designs in attachments 16 and 17. V 2. Attachment 14, Mitigation Measure (MM) 4.4-3a indicates that the stormwater, from the processing site will not enter the pit but does not disclose where or how the storm water will be handled. Impact 4.4-4 indicates "Internally generated stormwater will be retained on-site", then indicates a permit will be required to allow this water to go off-site. The plan needs to define and analyze what is actually proposed either on-site retention or on-site detention with drainage to a natural water course? 3. Attachment 14, MM 4.4-3b, how will floodwater be drained from the pit? See the second paragraph on page 243 "As a worst case, in theory, overflows could erode down through the buffer and Little Chico Creek could be diverted, in its entirety, through the created .lake." How will the pit and subsequent, reclaimed lake.be operated and maintained to protect the existing Little Chico Creek? 4. Attachment 14, MM 4.4-3c, the channels to be improved and proposed improvements need to be shown on the plans and fully addressed in the text. f It is unclear whether ditches within 1,000 feet on the east side or ditches on the east side to 1,000 feet southerly (no plan view associated with text) are. proposed to be improved to a 10 -year capacity. No design calculations or plans were M&T Reclamation Plan Comments June 22, 2005 Page 2 of 2 provided for these ditches. The flood impact studies by NorthStar Engineering do not show the boundaries of the 10 -year event, however the FEMA mapping indicates the 100 -year flood plain extends more than 1,000 feet east of the mine site and includes the topsoil stockpile areas. What is the purpose of improving the ditches on the east side to a 10 -year design capacity? Provide analysis for the impacts of the topsoil stockpiles to the flood plain elevations. Also this mitigation measure identifies the fact that all the proposed levees will be overtopped by flood flows from. the Sacramento River, but does not identify erosion control measures to be taken to protect the levees and pit slopes during operation or to provide protection for the reclaimed lake. 5, Attachment 14, pages 243 and 244, proposed project with and without Batch plants identifies a 50 -foot not 100 -foot wide buffer between Little Chico Creek and the northern edge of the pit. This conflicts with other information contained in the document, including attachment 6. 6. Attachment 14, it appears pages" are missing from the document so a complete evaluation cannot be made. Page -244 is identified as 4.4-73, page 245 is identified as 4.4-75 and the content does not flow from one page to the next.. Also page 245 (the last page of this attachment) ends in the middle of a sentence. Provide a complete, comprehensive copy of this attachment for review and• comment. 7. Attachment 16 provides some design calculations for a Little Chico Creek bypass channel, but does not provide information with respect to the construction location or design flow of 1,000 cfs. 8. Attachment 17 provides a design for an overflow weir for Little Chico Creek, but does not provide a backwater analysis for the flood plain, and does not address how Sacramento River overflows will react to the weir and setback levee. The design appears to be for the 50 -year event, not the base flood, 100 -year event. Page 304 profile, is the left levee looking upstream or downstream. Sections 1, 2 and 2.5 appear to intersect the pit, but there is no information with respect to the sections looking upstream or downstream and the pit is not shown. cc: Mike Crump, Director of Public Works (File 180.2) �% T rF o p p d emoranumJ_ o ° TO: Mike Crump, Public Works Director FROM: Dan Breedon, Principal Planner w SUBJECT: M&T Chico Ranch Mine DATE: May 23, 2005 Department of Development. Services Planning Division ° Mike, This document ("Reclamation Plan,.and Supporting Documents") represents Baldwin Contracting Companies response to the Department of Conservations critique of their submitted reclamation plan pursuant to SMARA. Some.of the issues that,the DOC comments upon involve drainage, 'flooding,engineering and design information pertaining to these subjects. I am requesting that the Department of Public Works review, Bald iw n's responses prior to accepting this document as complying with:SMARA and the concerns brought up by DOC. The area that I would request Public Work's input on' concerns the "Geotechnical Requirements, Hydrology and Water Quality" Section (Items.3 -5) of DOC's June 10, 2004 letter. Although this project has been continued off the Agenda, I am requesting a response from your Department within the next 30 days. Thanks for your attention to this matter. I am also requesting that the "Reclamation Plan. and Supporting Documents" provided with this Memo be returned to me when your review is completed.