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PublicWorksAgenda2022January25 COS COUNTY FRE ERICK Department rt uent of Public Works 4 [ -s4 , t FAX. 540/678-0682 MEMORANDUM TO: Public Works Committee FROM: Joe C. Wilder, Director of Public Works SUBJECT: Meeting of January 25, 2022 DATE: January 19, 2022 There will be a meeting of the Public Works Committee on Tuesday, January 25, 2022 at 8:00 a.m. in the conference room located on the second floor of the north end of the County Administration Building at 107 North Kent Street, Suite 200. The agenda thus far is as follows: 1. Discussion/update on sinkhole issue in Crystal Lake/Cherokee Dam in the Shawneeland Sanitary District. (Attachment 1) 2. Public Works project updates. 3. Miscellaneous Reports: a. Tonnage Report: Landfill (Attachment 2) b. Recycling Report (Attachment 3) C. Animal Shelter Dog Report: (Attachment 4) d. Animal Shelter Cat Report (Attachment 5) e. Shawneeland Sanitary District Advisor Committee Special meeting minutes (Attachment 6) f. 2021 Holiday Usage Summary (Attachment 7) JCW/kco Attachments: as stated 107 North Kent Street, Second Floor, Suite 200 9 Winchester, Virginia 22601-5000 "�q�l�,`quuuuM.�pu�l al Harrisonburg Office Winchester Office 1356 N.Main Street 220 Imboden Drive,Suite A Harrisonburg,VA 22802 Winchester,VA 22603 Phone:540-434-0400 Phone: 540-313-4270 Fax:540-434-0447 VZW Fax: 540-434-0447 Viola Engineering,PC December 2, 2021 Joe Wilder,Director of Public Works [email jy ➢jIdc,r�y)f yaa.u,"�S] Frederick County, Virginia 107 N. Kent Street Winchester, VA 22601 RE: Revision 1 -Report of Geophysical Investigation �,'rysq d Lake uu:Uo: lmcs6g�gJ n (Qn�EgkV �D]) 152 Tomahawk Trail, Winchester, VA VEPC ProjectNo: PTL-212862 Mr.Wilder: A three-dimensional(31)) electrical resistivity imaging(ERI) survey was performed at the referenced site to evaluate recently developed karst features located along the southeastern bank of Crystal Lake. Site investigation and report preparation were conducted in accordance with Frederick County Task Order 2017- 13 (Date: 10/27/2021) and scope of services developed by our office (Proposal Date: 10/21/2021). The lake and earthen impoundment, Cherokee Dam, are owned and operated by Frederick County with funding provided by the Shawneeland Sanitary District. Site karst hazards are well documented at Crystal Lake, and subsurface topology has impacted the performance of the lake dating back to its construction in the 1960's. Investigation and sinkhole remediation activities have taken place over the past 20 years with fluctuating drainage rates occurring throughout the lakes operational history. Sometime in early October 2021, two (2) well defined sinkholes developed along the eastern shore of the lake; subsequently, accelerating lake drainage to a rate measured at approximately 150 gallons a minute at the spring located north of the historic Council House. As a result, the lake water elevation dropped approximately 10 to 15 feet. This prompted a subsurface evaluation of geologic conditions to ascertain potential remediation scope and estimated costs. A three-dimensional electrical tip �- resistivity survey (ERI) was conducted, by our office, to evaluate subsurface sinkhole drainage conditions. A 3D rectangle survey section was established,as shown on the attached Location Plan with six(6)parallel ERI survey lines conducted with Figure 1.Dam Construction electrode spacing maintained at eight(8)feet. Three-dimensional resistivity imaging is a geophysical technique utilized to measure the in-situ resistivity of earth materials, i.e., how difficult it is to pass an induced electrical current through the subsurface. Resistivity is the inverse of conductivity.Therefore,resistivity imaging is a measurement of the conductivity of the subsurface materials at the site. Generally, soils are more conductive than competent bedrock and can be imaged with this technique. Karst terrain soils associated with sinkholes, voids, solution channels, bedrock seeps and incipient sinkholes are typically cohesive and very moist. Therefore, they are more GEOTECHNICAL•GEOPHYSICAL ("'Vows, CONSTRUCTION•MATERIALS II Revision 1 -Report of Geophysical Investigation ("cr.� 'd I.okQ'..4rnkholQr Rn° &!< IrAn (("lrQrrr>kcc CVwI2 152 Tomahawk Trail Winchester, VA 22602 December 2, 2021 Page 2 conductive than the surrounding bedrock or other soils.In addition,voids and caves can possibly be imaged provided a contrasting resistivity gradient exists between the target and the surrounding earth materials. SITE EXPLORATION Cherokee Dam is located perpendicular to the strike of bedrock underlain by various geological formations, several of which include soluble limestone. We understand the site and dam embankment is underlain by several geologic formations with limestone inclusions that are solution prone according to published maps, review of previous site study, and grouting program performed by Hayward Baker. Based on a review of the grouting program,we summarize that grouting began in November 2008 and was terminated in April of 2009. A total of 33 borings were injected with grout to depths of 150 feet, as referenced from the top of the dam, with a cement grout/bentonite additive. Records indicate a total of 2097 cubic yards of grout was injected to develop a subsurface curtain that appeared to minimize water flow through subsurface voids at depth. However, it was stated some leakage is inevitable in this karst geology. We conclude that it is nearly impossible to effectively stop leakage in karst geology nor can any grouting plan guarantee similar future sinkhole development will not occur.However,targeted remediation can significantly reduce the likelihood of drainage through karst development and reduce subsurface drainage rates. A three-dimensional ERI survey along ��x ((.)p gnfflx�...Vuncs.running east to west along the downstream slope and toe of Cherokee Dam.The study included a d up o�c d up o�c array resistivity survey utilizing the Advanced Geosciences, Inc. (AGI) SuperSting R-8/IP Passive Earth Resistivity System. The ERI lines were spaced approximately 16 feet apart with a length of 664 feet each. The resistivity lines were established with an electrode spacing of 8 feet to gain a maximum resolution and imaging depth of approximately four (4) and 130 feet, respectively. Anomalous resistivity zones were mapped in an effort to �� a identify flow paths which traverse the survey area �rrt�y�rrn �Una' to distinguish potential remediation areas. Further, lrr J� f/i � bpi✓rrrG((��if(lrrir prr resistivity imaging data was processed and inverted using AGI s proprietary 3-D resistivity inversion software,EarthImager 3-D,to generate the inverted p,, ; ; ,�����✓�r i��;r �,,�,;,,�y�y�;r��p„ �t r ,/';;,rtr���� resistivity sections. Terrain correction was performed utilizing high resolution elevation data obtained from USGS 3DEP one-meter Light Detection and Ranging (L1DAR) bare earth elevation maps.Electrodes were located in the field with multi-band RTK GNSS receivers with a nominal location accuracy of less than three (3) Figure 2.ERI Field Investigation centimeters. SUBSURFACE CONDITIONS Electrical resistivity imaging is a nondestructive investigation technique that can be utilized to detect large anomalously deep and/or wet soils of the type commonly associated with incipient sinkholes or saturated soils, fractures, or pockets between more competent rock. Resistivity imaging was utilized as an indicator of potential wet soils or flow paths and not as an absolute identifier of the problem. In general, higher GEOTECHNICAL•GEOPHYSICAL ("'Vows, .�.9»a CONSTRUCTION•MATERIALS II Revision 1 -Report of Geophysical Investigation ("bwr.S'dI.or"fQ'..4f1?r"fholQrRn°Qr.S f&!< IrAn (("a`tQrb°r>r"ccCVwI1. 152 Tomahawk Trail Winchester, VA 22602 December 2, 2021 Page 3 resistivity values are interpreted to represent non- porous competent bedrock or dry soil conditions, , r and conversely, lower conductivity values are e � sty interpreted to represent moist or saturated soils , and/or water filled voids, fractures, and other ��` structural discontinuities within the bedrock/soil mass. Resistivity imaging of the project site suggests variable moisture conditions beneath estimated top of bedrock likely indicated zones of water infiltration.Zones of higher resistive material likely represent competent bedrock while lower resistivity values were observed along the existing dam outfall Figure 3.Sinkhole Development Along Shoreline barrel and buried piping(siphons).A discontinuous low resistivity zone is noted on all ERI sections along the eastern edge of the ERI data.This area is indicative of fractured bedrock harboring water flow. Further, it is believed the contact between dissimilar geologic formations is closer to the site than is mapped leading to accelerated bedrock degradation.A zone of probable remediation was identified along the eastern extents of the survey area as mapped on the attached Location Plan and Inverted Resistivity Sections.An area of low resistivity subsurface conditions was noted due west of the dam outfall pipe only in a handful of sections. It is believed this hydraulic feature is derived from water infiltration at the surface near the end of the outfall pipe. CONSTRUCTION RECOMMENDATIONS We understand Crystal Lake is a prominent feature of the Shawnee Land community and is admired by many residents. However, extensive subsurface remediation of previous karst features has left some weary of significant capital expenses for its continued operation. Multiple remediation options are available with varying probability of long-term success; however, any remediation approach selected will not guarantee the end to sinkhole development within the local geology going forward. Currently(as revised 12/2/21), Crystal Lake elevation has dropped to a consistent level of 157 inches below normal pool elevation and flow measured at the spring box below the Council House has stabilized to 136 gpm (down from 175 gpm) and flowing with negligible turbidity. These factors may remain constant for a period of time to permit remediation, if so elected. Some well-suited methods, arranged in ascending cost, may include: 1.) Grouting of near-surface voids, deep remediation excluded,in the existing karst features to include backfilling existing sinkholes (2) at the surface to promote public safety leaving existing deep conditions unchecked. This would be economically achieved by rough grading an access lane to near the karst features to permit backfilling with 2000 psi lean concrete with 50 lbs of bentonite metered into the concrete while discharging. The concrete volume may be expanded by including bank boulders to the concrete/grout mix during discharge. We estimate a budget cost of$7,500 to complete this alternative. However, once the sinkholes are backfilied, the advantage of filling with polymer grout is lost without drilling addition holes to inject grout to better fill voids if decided at a later date. 2.) Near surface and drainage path filling with water-activated semi-rigid polyurethane foam injection resin. Dye tracing is conducted to ascertain travel time through karst drainage paths. Specially GEOTECHNICAL•GEOPHYSICAL ("'Vows, .�.9»a CONSTRUCTION•MATERIALS II Revision 1 -Report of Geophysical Investigation ("bwr.S'dI.or"fQ'..4f1?r"fholQrRn°Qr.S f&!< IrAn (("a`tQrb°r>r"ccCVwI1. 152 Tomahawk Trail Winchester, VA 22602 December 2, 2021 Page 4 formulated foam is pumped into the exposed sinkhole(s) and proportioned to activate at set intervals to plug subsurface conditions. Chemicals are certified to NSF 61-5 (approved for contact with drinking water—see attached Certified Product Listing). Please refer to attached Case History for more information provided by Mr. Stuart Baber of American Concrete Services. We suggest that Mr. Baber be contacted for additional Case Histories of grouting sinkholes in karst geology for further consideration. 3.) Deep chemical grouting to develop drainage curtain walls downstream from the dam. Areas noted on attached location plans. 4.) Extensive grouting similar to remediation activities conducted for previous karst feature remediation downstream and/or within reservoir. Areas noted on attached location plans. Based on the 2009 remediation history and existing subsurface flow that developed after a period of 13 years,we recommend injecting apolyurethane resin at this time to minimize subsurface flows as mentioned. This approach incorporates additional deep remediation at a fraction of the cost of conventional pressure grouting. The resin can be properly mixed with an accelerant to cause a solid plug to set at a precise time to effectively fill the karst void(s) along the drainage path. Further, our review of products and procedures indicates that the resin can be pumped into the existing sinkhole, which avoids drilling injection borings along the dam embankment thereby reducing cost and time for completion. We suggest that a preferred Contractor be contacted to evaluate the site to determine a budget cost to restore the lakes level to near normal utilizing a polyurethane resin. Based on a quote for 500 gallons of bulk material,we estimate a cost to remediate Crystal Lake ranging between $60,000 and $380,000 depending on the severity of voids in the underlying karst geology. Upon completion, we recommend that the exposed throat of the sinkhole(s) be backfilled with a lean concrete (2000 psi concrete) amended with high yield bentonite gel (powder) at a typical rate of 50 pounds/cubic yard of concrete. This will provide a tight sealing plug that will promote public safety. Further site remediation work may be required in the future, as this approach will plug the current karst drainage path. Active maintenance, incorporating this or comparable techniques, may likely result in a lower total site remediation cost if future subsurface leaks develop.We recommend that Mr. Stuart Baber be invited to speak of this process at the next Homeowners Board Meeting based on his expertise and to answer questions accordingly. GEOTECHNICAL•GEOPHYSICAL ("'Vows, ��.9»a CONSTRUCTION•MATERIALS II Revision 1 -Report of Geophysical Investigation ( cr.S'd I.okc SinkholQr Rn°Qr.S fwg!! Ion (("a`tQrb°okcc C VwI1. 152 Tomahawk Trail Winchester, VA 22602 December 2, 2021 Page 5 LIMITATIONS This report has been prepared in order to aid in the evaluation of this site and to assist remediation activities related to existing karst conditions. Our scope is limited to the specific project and location described, and the project description represents our understanding of the significant aspects relevant to soil and geologic characteristics. The interpretations and recommendations in this report are based solely on the information available at the time this report was prepared. Subsurface conditions may vary from those encountered at the survey locations. Further exploration activities can be provided to aid in targeted remediation activities as site planning progresses. We appreciate the opportunity to provide engineering exploration services on this project.If we can be of any other assistance,please do not hesitate to contact us. Respectfully, LT LTH oH p�.�/ O �� ,pF�i o� 12/02/21 2 12/02/21 � U q U q Mark A. Viola,PE MARK A. VIOLA TIMOTHY PAUL VIOLA Owner, Principal Engineer Lic. No. 022705 Lc. No. 0402056657 F`�ss/0NA1- /0 N A L Timot y P.Viola,PE Project Engineer Attachments: Location Plan(1 Sheet, Raster) Inverted Resistivity Sections (8 Sheets, Raster) Locaquou:...P iu: &.Im coed &s Certified Product Listing& SDS -AP Fill 720-Polyurethane Injection Resin Case History -2016 Leon Lake Emergency Seepage Repair Plan& Grout Plan GEOTECHNICAL•GEOPHYSICAL ("'Vows, ��.9»a CONSTRUCTION•MATERIALS II �: .,�__NTY Off` CK Department of Public Works 40/665- 64; FAX- 40/678-068 MEMORANDUM TO: Public Works Committee FROM: Joe C. Wilder, Director of Public Works SUBJECT: Monthly Tonnage Report-Fiscal Year 21/22 DATE: January 4, 2022 The following table shows the tonnage for the current fiscal year. The average monthly tonnage for fiscal years 03/04 through 21/22 is also listed below: FY 03-04: AVERAGE PER MONTH: 16,348 TONS(UP 1,164 TONS) FY 04-05: AVERAGE PER MONTH: 17,029 TONS(UP 681 TONS) FY 05-06: AVERAGE PER MONTH: 17,785 TONS(UP 756 TONS) FY 06-07: AVERAGE PER MONTH: 16,705 TONS(DOWN 1,080 TONS) FY 07-08: AVERAGE PER MONTH: 13,904 TONS(DOWN 2,801 TONS) FY 08-09: AVERAGE PER MONTH: 13,316 TONS(DOWN 588 TONS) FY 09-10: AVERAGE PER MONTH: 12,219 TONS(DOWN 1,097 TONS) FY 10-11: AVERAGE PER MONTH: 12,184 TONS(DOWN 35 TONS) FY 11-12: AVERAGE PER MONTH: 12,013 TONS(DOWN 171 TONS) FY 12-13: AVERAGE PER MONTH: 12,065 TONS(UP 52 TONS) FY 13-14: AVERAGE PER MONTH: 12,468 TONS(UP 403 TONS) FY 14-15: AVERAGE PER MONTH: 13,133 TONS(UP 665 TONS) FY 15-16: AVERAGE PER MONTH: 13,984 TONS(UP 851 TONS) FY 16-17: AVERAGE PER MONTH: 14,507 TONS(UP 523 TONS) FY 17-18: AVERAGE PER MONTH: 15,745 TONS(UP 1,238 TONS) FY 18-19: AVERAGE PER MONTH: 16,594 TONS(UP 849 TONS) FY 19-20: AVERAGE PER MONTH: 16,973 TONS(UP 379 TONS) FY 20-21: AVERAGE PER MONTH:16,803 TONS(DOWN 170 TONS) FY 21-22: AVERAGE PER MONTH:18,362 TONS(UP 1,559 TONS) MONTH FY 2018-2019 FY 2019-2020 FY 2020-2021 FY 2021-2022 JULY 17,704 17,956 17,677 17,893 AUGUST 18,543 17,267 16,517 21,437 SEPTEMBER 14,799 17,985 16,789 19,306 OCTOBER 18,158 22,528 20,127 18,215 NOVEMBER 15,404 17,304 15,432 16,927 DECEMBER 14,426 14,362 15,496 16,391 JANUARY 13,973 14,913 14,480 FEBRUARY 12,764 13,380 12,030 MARCH 17,079 15,533 18,758 APRIL 20,313 17,475 18,627 MAY 19,443 17,010 17,105 JUNE 16,519 17,968 18,594 JCW/gmp uV.°9 PiI yi,,,,,,: N O O O O O O O O O O O N M M I� O �T (0 O I� (0 I� M I� �T O M O N O LO O M (0 (0 O O M O (0 O LO 00 (0 00 M M (0 (0 M I� M N � M O O �T I� M M (0 O_ �T �T O N M N (0 I� V O M 00 00 I� O O V N (0 00 N M O (0 (0 O V O O 00 Lf) N 00 M V M V V O O �hiiiiiiiii J m I-- (O Lf) m O N (O (O I-- I-- Lf) N O N N (O I-- (O 00 V O 00 N W) O O O co O V V Lf) 'I^"""" CO Lf) (0 (0 O W) N N 00 I-- O '' W) I-- co N O N V (O N O O co O O 00 co (O I-- O '' O Lf) V V V V V 00 N N N N N (O O O I-- (O V co O co O 00 (0 (0 N — V CO O 11' CO CO O _"P N (O (O (O (O (O (O (O Lf) Lf) Lf) Lf) LW) V LW) M N N N N N N N N N N N I� a"9'IU 0 00 M N 0 0 0 0 0 N O I� O V O LO 00 00 I� 00 O O O O O O O O O O 00 O (O (O 00 O 00 (O O LO O �' �' N N CO Il- O 0') Lf) 00 I-- N 00 M 00 11' N 00 N O O r- N O O N V 00 I, N M � N _O (O M 00 O N O N (O 7, (C 00 I� (O CO I' m N M O O 11' � (O O O N O 00 I� N O V Lf) (O 00 m V 00 V 00 �' (O Lf) O O V N O O I-- 00 I-- O M N M N V O I-- Lf) O N M I� Lf) V V co N N N N V — N O M O M M (O co- �' N M O Lf) N co (O U M M N N N N cn O O O CD O O O O CD O O O M CD 0 0 0 0 0 0 �' O I-- 0 0 V V (O 00 CDN O O N N O CDm m m O N m CD7 CD CD P V O co O 00 00 (O Lf) 00 (O O r- V Lf) V N Lf) (O (O O (O � Lf) V � 00 00 O O U I-- Lf) 00 (O co N N I-- (O W) O N 7 N V I-- Lf) V 00 N M (O N V Lf) W N N N N N co (O O O M O 00 M O 00 (O M O O 00 00 I-- Lf) (O Lf) N J — M M V Lf) 11' V Lf) (O Lf) V V V V V M M N N W co N N O CD O O O CD O O O V O CD O O O O CD O O O O O N x 0 V V m O N m N O O (O N N V O O N O (O m V W Lf) M 00 N O r- Lf) (O V7 V7 N N 00 V 00 r- Or- r- Lf) >- t M V V M M (O (O LO LO M I� � M M I� O � 00 N LL cn N V LO 00 CO CO N' N' CO M M N' N N V W CO O O cn a LL1 O O O O O O O N O N I� M M O O I� M O A N O O V 00 (O V O N 00 M M 00 LO O 00 O LO I� (O LO O N O Ur Lf) N N V N 00 (O Lf) N O M I� ,* - 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Shawneeland Sanitary District Advisory Committee MEMORANDUM TO: Joe C. Wilder,Director of Public Works FROM: Rhonda L. Sargent, Chairperson, Shawneeland Sanitary District Advisory Committ SUBJECT: Cherokee Lake Sinkhole(s) Remediation Recommendation DATE: January 18, 2022 Attached you will find minutes from the special SSDAC meeting held on January 10, 2022, as well as the minutes from the subcommittee meeting held on January 5, 2022 . The latter was formed to discuss the remediation options presented in Viola Engineering's report as well as possible funding options. During their meeting, the subcommittee voted to make a recommendation to the SSDAC at the special meeting held on January 10, 2022 that the resin injection option at a cost of up to $380,000 be approved. Consequently, the SSDAC voted unanimously to approve recommending that public works proceed with the necessary discussions and steps to proceed with the resin injection option as well as a request to pull funds from Shawneeland's reserve fund in the amount of$380,000 to have the remediation performed. Thank you in advance for your cooperation in this matter. /rls Attachments: as stated ^C) c O O O 2:1 s O C� p N nc� cn cn N U O N U ^u N U N U OU O U � O cc O U O O 140. N bA Q Cc) p p p f� o O O P. � � O 3 N i�.i cn ^u to U A '2 ~ 0 O by O UO O O O uO by fl O n a� a� C,3bA C,3 C,3 3 -- o3 ° > �° oq ea o x o o o 14. eC O p 4• O O V O on `4� cn O r� O o o 0 o ocn cn U cn U .cn �4. 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Q to o `o o � ° ° O N N � r � ^U � u > N N ct ,� ' (� O y 4-i --i cn cn O cn cn G N C) to cn v O O O .s E � w H cG H H � H � Q O a 0 o ° ° �4. p oU 4." .� 140. � 'InnOU cn � p O v CA U N O O O cn N ° O p bA O U U UIj U O cn 0O O N V1 N U 0 O N CO sue" U U s p U U cd .0 CO P. cl O � O C U p '0 0 N o3 to y� U ^C3 O a O C=) yU U to 'U v rs v o a� u j � ƒ � j � ƒ ƒ ƒ o / / e u § o ® \ § / 2 $ ( @ k \ R S \ l .2 \ ƒ 2 = o \ q o �401 A § \ o � � § ƒ 2 ƒ 2 ƒ : / 7 g § % u t � \ 2 \ o � � Shawneeland Sanitary District Advisory Committee Subcommittee Meeting Minutes January 5, 2022 Sanitary District Office, 50 Tomahawk Trail Time: 7 PM Subcommittee Attendees: Committee Members Present: Andrea Poe, Jeny Guy and George D. Bishop Committee Members Absent: Alec Bouldin and Kenneth Baker Staff and others present: Joe C. Wilder, Director of Public Works, Kevin Alderman, Manager, Shawneeland Sanitary District and Rhonda Sargent, SSDAC Chairman Minutes Taker: Andrea Poe Agenda 1. Call meeting to order 2. Attendance 3. Recent Cherokee Lake engineering evaluation summary/discussion 4. Available grants for Cherokee Lake remediation 5. Decide on the best method presented by the engineering evaluation 6. Adjourn the Meeting Meeting Minutes • Meeting was called to order at 7:05 PM. • Joe Wilder- There is a divide of geology where a joint is causing a leaking issue with sink holes opening. The geologic joint has karst limestone along east side of lake and shale geology on west side of lake. The leak is occurring where the two geologies contact each other. Nearly $1,000,000 was spent reducing the leaks using grouting during the last remediation in 2008. Communication is occurring to discuss how to address the current leaking issues. New technology may offer some options not previously available. The upcoming committee meeting will provide additional information regarding the solutions available from Viola Engineering. Reserve money will have to be used to fix the leak. The Reserve is currently around $1.48 million. One (1)year's budget is the goal for the reserve total. Chemical grouting may be the solution but must be done while the sink holes are open before closing them. • Jeny Guy -How much is the dam compromised? • Joe Wilder- The leak is 40-60 ft below the bottom of the dam making it not a large concern because the zone is far below. • Joe - The chemicals used can be activated for controlling how it expands. We could work with Viola or collect bids from other companies. Specialty contractors can be hired • Rhonda Sargent-Does this company with Viola have any videos of before and after? • George D. Bishop -What would be the responsibilities of the Shawneeland Sanitary District crew? • Joe Wilder-A road would have to be created to allow for the work to be done at the sites. Chert is hard rock that is present making fill necessary to build an access road. • George D. Bishop -Using just concrete does not seem sustainable. • Joe Wilder-Plugging the crack with the chemical grouting is a possible long-term fix. The engineers have evaluated multiple methods,but the many springs present prevent certain methods from being viable options. • Kevin Alderman- There may be a property on the lake that may make building an access road more cost effective. • Joe Wilder- The Advisory Committee may recommend the Subcommittee speak with the landowners of the properties bordering the lake to be granted access. • Joe Wilder-During the special called 1/10/22 SSDAC meeting, examples may be provided to demonstrate how the technology has been applied successfully. • George D. Bishop and Rhonda Sargent-A video demonstration would benefit the attendees at the next meeting. • Jeny Guy -Any concerns for the aquifers should be validated and addressed at the next meeting. • It was unanimously decided by the subcommittee that the deep chemical grouting would be the best option as a long-term solution at a cost of up to $380,000. • Joe- The decisions from the subcommittee will pass to the advisory committee, followed by public works, and the finance committee and then the board of supervisors. Grants • Shawneeland does not meet the criteria for the Natural Resources Conservation Service Virginia's Environmental Quality Incentives Program and Virginia Department of Conservation and Recreation grant. No other explored grants were applicable. • Andrea Poe-Pursuit and acquisition of other grants would require the recreational area be transformed for more conservation purposes rather than private recreational. The lake would likely cease to exist. • Meeting was adjourned at 8:45. Next Meeting Agenda 1/10 1. Call meeting to order 2. Cherokee Lake engineering evaluation-final report (Informational purposes only) 3. Subcommittee comments - The subcommittee will report on discussed grants, costsibenefits, and the current reserve to make a recommendation to the advisory committee. 4. Public Comments 5. Adjourn the meeting CO r COUNTY ofFR ERICK Department t f Public Works .5401/665-5643 FAX. 540/678-0682 MEMORANDUM TO: Public Works Committee FROM: Gloria Puffinburger, Solid Waste Manager SUBJECT: 2021 Holiday Usage Summary; Citizens' Convenience Sites DATE: January 19, 2022 During the 2021 holiday season, staff conducted traffic counts at the county's two busiest sites, Greenwood and Albin, from Christmas Eve through Sunday, January 2. During the period, an average of 634 vehicles visited the Greenwood facility each day and 622 vehicles utilized the Albin facility. As is traditionally the busiest trash day of the year, 460 vehicles were recorded at the Greenwood facility and 560 at the Albin convenience site during the 5-hour Sunday shift on December 26. This is a drop from 2020 traffic totals since the sites were open only five hours, not the normal full day of 11 hours. 30-yard open top containers were staged at the Greenwood, Double Toll Gate and Gore facilities in order to keep those facilities open during the entire Sunday shift. The containers were filled at each location and each hold about two tons of uncompacted refuse. Overall, the county's ten neighbor convenience sites accepted 423 tons of refuse attributable to the Christmas season and ending New Year's Eve, December 31, an increase of five percent over 2020. The Geenwood facility accounted for 65 tons of the total refuse and Albin, 69 tons. Heavier than normal trash flows continued through the post New Year's weekend. Staff would like to thank the trustees of the Community Inmate Workforce who worked with us at the Greenwood and Albin facilities on December 26, off-loading vehicles and diverting cardboard. /gmp 107 North Kent Street, Second Floor, Suite 200 9 Winchester, Virginia 22601-5000