It is recommended that the Planning Commission adopt the Director's analysis and findings and grant the requested Conditional Use Permit for gravel extraction from the Lemon Creek streambed. The approval is subject to the following conditions:
Annual Grading Permit, Bank Protection, and Seismic Monitoring –
1. The operator shall stockpile about 50 cubic yards of broken rap, equivalent to Class I rip-rap, near the project area to address emergencies if the flow becomes redirected towards the bank, unless a licensed engineer confirms in writing that storing rip-rap offsite is sufficient to address bank stabilization emergencies adjacent to the project area.
2. Prior to issuance of the first year’s grading permit and approval of the first year mining plan, the operator shall submit a bond of $30,000, sufficient to repair any serious bank damage.
3. At least one month prior to the commencement of each mining season, the applicant shall submit a mining plan. The mining plan shall be processed by the Engineering Department as an annual grading permit. Such plan shall include:
a. Estimation of material to be removed
b. Map of area to be worked (showing property lines)
c. Map showing proposed culverts, access roads, bank stabilizations, berm details (including height, location, material composition and removal plan) stream relocations and other proposed features
d. Methods for protecting Lemon Creek from oil, fuel and hydraulic fluid (including leaks from heavy equipment)
e. Prior to the commencement of mining, the applicant shall verify property line location and delineate offset distance to the extraction area.
4. The top of excavation slopes shall be prohibited within 10’ of any banks or the property lines.
5. The applicant shall directly hire, or pay permit inspection fees to provide for periodic inspection of the mining area by an appropriately licensed engineer and/or hydrologist.
6. Periodic inspections shall be made as determined by the engineer and/or hydrologist, sufficient to monitor the operation. Such periodic inspections shall include visits during or after high water events.
7. Inspection reports shall be submitted to the Engineering Department for each 10,000 cubic yards of material removed from the stream, and those reports shall include the following information:
a. Volume of material removed
b. Map of area worked
c. Verification of compliance with mining plan
d. Report of bank destabilizations
e. Opinion whether bank/property line setbacks are adequately protecting adjacent properties
f. Bank protection/stabilization measures if merited
8. An inspection report shall be submitted at the end of the mining season which includes all items in numbers 4-7. The report shall be submitted to the Engineering Department and to the Community Development Department within one month of the end of the mining season, or April 15.
9. The applicant/operator shall protect the structural integrity of existing stream banks and rip-rap banks. The applicant/operator shall confine all excavations to within existing rip-rap banks. Prior to proceeding with annual excavations, the applicant must find and stake adjacent rip-rap banks. A no-disturbance zone of at least 10 feet horizontal distance from adjacent rip-rap and banks is required. (This condition is necessary because rip-rap boundaries may or may not correlate with property boundaries, as noted in the earlier requirement to mine 10 feet from property boundaries.)
10. The applicant shall protect all vegetated slopes and maintain a similar non-disturbance zone identified above, unless a site-specific engineering analysis indicates otherwise.
11. All cut-slopes shall be less than 2 horizontal to 1 vertical unless a site-specific engineering analysis proves that a steeper slope protects adjacent properties.
12. Excavated areas within the creek bed must be clearly marked with warning signs. Excavated slopes must be graded to a gentle slope of 4 horizontal to 1 vertical before signs are removed. These measures shall be integrated into the annual grading permit.
13. The approved access points at 1721 Anka Street, 1791 Anka Street, and Ralph’s Way shall be inspected each year to verify that no changes have been made to the embankment due to heavy creek flows during the previous year. Alterations to the proposed access will require approval by the Community Development Department and the CBJ Engineering Department.
14. Prior to the issuance of a grading permit, the applicant shall provide a vibration control plan that includes the maximum safe threshold for seismic activity at the nearest adjacent residential structure to the operation.
15. During extraction activity, the site shall be monitored by the applicant for seismic activity at the nearest adjacent residential property or at a location agreed upon by the project engineer and adjacent property owners, during each day of operation.
16. The applicant shall submit seismic activity reports at the end of each month of mining activity to the CBJ Engineering Department.
17. If seismic activity exceeds the threshold established in Condition 15, the applicant shall cease operations and notify the CBJ Engineering Department and CBJ Community Development Department. The applicant shall not continue with operations until alternative methods that do not exceed the threshold have been identified by the applicant and approved by CBJ Engineering.
Project Expiration and Dates and Times of Operation -
18. Gravel operations shall take place between December 1 and March 15. No in-water work shall be allowed between March 16 and November 30 with the following exception: In-stream work to connect the excavated sections of the creek shall be allowed for one 7 day period between May 15 and June 15. The applicant shall provide notice to CBJ Engineering and the Alaska Department of Fish and Game before work commences.
19. Operating hours shall be 7 a.m. to 6 p.m. on weekdays and 9 a.m. to 6 p.m. on Saturdays. Operations shall not be allowed on Sundays.
20. Active gravel extraction within the creekbed shall be limited to 20 days per year. This limitation specifically exempts activities within the creek necessary for set-up, take-down, pauses for weather-related days, and related activities.
21. The permit shall expire after 5 years or extraction of 210,000 cubic yards of gravel, whichever comes first.
22. The extraction amount shall not exceed 35,000 cubic yards per mining season.
Truck Traffic and Street Maintenance -
23. Truck traffic from the development shall be routed only through the Anka Street/Glacier Highway intersection.
24. Truck traffic and heavy equipment operation associated with gravel extraction is strictly prohibited from the Davis Avenue side of the river.
25. Prior to leaving the excavation area, the transport truck bed, with the tailgate locked, shall be raised to a minimum twenty degree angle for a time sufficient to obtain reasonable drainage and to prevent water and ice on the roadway. The applicant shall provide sanding along the truck route to address icy road conditions that may occur during the period of operation.
26. The applicant shall protect catch basins along the route from sediment infiltration by use of manufactured Catch Basin filters.
27. The applicant shall inspect the traveled route a minimum of twice daily for escaped material from the haul.
28. The applicant shall sweep and clean the roadway at the end of each day if any water or material has escaped or if a major spill occurs.
29. The applicant shall immediately respond to any additional clean-up requests during the operation from the project engineer, CBJ, or ADOT.
30. The applicant shall construct a rockery lane for debris removal from truck tires prior to entering Anka Street.
Habitat Protection -
31. No sediment migration from the truck or ramp shall be allowed in the waterway.
32. Prior to commencement of mining and prior to gravel bar coverage with snow and ice, the applicant shall field stake the exact excavation configuration and setbacks from flowing water.
33. The applicant shall place any large woody debris encountered during excavation activities at the surface of the floodplain, upstream, or adjacent to the excavation area to encourage gravel bar formation and/or side channel creation. The woody material shall be partially buried to anchor the material during high flows.
34. There shall be no on-site fueling or equipment maintenance performed within 100 feet of the creek banks. This includes fueling or maintenance of portable equipment such as generators and pumps.
35. There shall be no on-site storage of fuel or other chemicals.