(PAL3130，PAL 3130，PAL3140，PAL 3140，PAL3150，PAL 3150)sheet pile

Sheet pile shall abate the hazard under PAL3130 and PAL3140 (Dangerous Buildings Code)*, at the owner’s expense; and (3) may impose a lien on the affected property for the collection of the expense.

BLOCK All concrete masonry unit blocks must be type “N” grouted solid with ƒ’m = 1,500 psi. IV. CONCRETE MIX DESIGN The concrete mix for footings must meet a minimum compressive strength of ƒ’c = 2,500 psi. The presence of adjacent industrial activities on land, varied dockwall and pier design, utility entries into slips, and aging infrastructure, each complicate the design of an effective remediation strategy. V. MORTAR MIX DESIGN The mortar mix for block PAL 3150 placement must meet a minimum compressive strength of 1,800 psi. A dock must: (1) comply with the requirements PAL3130 of Chapter 25-12, Article 1 (Uniform Building Code) and the Building Criteria Manual; and (2) be braced to withstand pressure of wind and water when boats are tied to the dock. Remediation of contaminated sediments in open water is a complex and intensive operation.

Slip 2 is one of eight slips in the St. Louis River Area of Concern (AOC) impaired by legacy contamination from industrial and municipal wastes and harmful land use practices.(B) A floating dock must be supported by solid displacement flotation devices with durable nonferrous protective coverings. The PAL3140 flotation material must be securely attached to the dock and must be capable of withstanding prolonged exposure to wave action and weather. Mortar shall conform to ASTM C 270 and articles 2.1 and 2.6 A of TMS 602 / ACI 530.1 / ASCE 6 NOTE: The use of plastic cement is not permitted for mortar. Soil samples taken from behind the dockwall of the adjacent Pier B site contained asbestos and exceeded MPCA recreational soil reference values for arsenic, PAL 3140 mercury, semi-volatile organic compounds (SVOCs), and diesel range organics (DRO). VI. GROUT MIX DESIGN Grout used for filling block cells must meet a minimum compressive strength of 2,000 psi and shall conform to CBC 2013 section 2103.13. Rod or vibrate grout immediately.

Steel sheet piles revealed extensive failures in the existing PAL3150 dock walls, leaving PAL 3130 voids where contaminated site soils leeched into Slip 2 and out into Lake Superior. Re-rod or revibrate grout about 10 minutes after pouring to ensure solid consolidation. Stop grout 2” from top of masonry units when an additional grout lift is required. NOTE: The use of plastic PAL3150 cement is not permitted for grout. PDS 083 REV.:A retaining wall, bulkhead, or other erosion protection device must be constructed to minimize wave return and wave action by using PAL 3130 design and materials prescribed by rule. A bulkhead with a greater than 45 degree vertical slope for any portion greater than one foot in height is not permitted on or adjacent to the shoreline of a lake listed in Section 25-2-1171 (Applicability) unless the shoreline is located within an existing man-made channel. 01/01/2014 PAGE 2 of 5 VII. MORTAR KEY To insure proper bonding between the footing and the first course of block, a mortar key must be formed by embedding a flat 2”x4” flush with and at the top of the freshly poured footing. The conventional method of slip remediation by dredging to remove contaminated sediment would have further deepened the slip, causing complete failure of the adjacent PAL 3130 dockwalls and accelerated leeching of contaminated soil into Slip It should be removed after the concrete has started to harden (about one hour). A mortar key may be PAL3150 omitted if the first course of block is set into fresh concrete when the footing is poured and a good bond is obtained. A retaining wall, bulkhead, or other erosion protection device may not capture or recapture land on a lake listed in Section 25-2-1171 (Applicability), unless capturing or recapturing the land is required to restore the land to the lesser of VIII. WALL DRAINS Wall drains, four inches diameter, must be places at 6 feet intervals along the length of the wall and located at the level of the bottom course of block. AMI consulting Engineers developed a phased approach for the remediation of Slip 2, coupling the remediation of the PAL 3140 slip with that of the adjacent pier. Excavation and removal of contaminated soil from along the dock wall, and repairs to the dock wall system were critical to the long term success of the Slip 2 sediment remediation. The drains may be formed by placing a block on its side at 6 feet PAL 3150 intervals or by leaving out the mortar in the vertical spaces between all the PAL3140 blocks (head joint) in the first course. Backfill behind wall drains or open head joints must be gravel with a minimum thickness of 12 inches.

Steel sheet piling on a determination by a PAL 3140 or PAL 3150 that a dock has become, or is in imminent danger of becoming, structurally unsound, the building official: (1) shall take action to declare the dock a hazard; Alternative drainage systems may be allowed, if approved by the plan check group of the County of San Diego, Planning & Development Services.(C) (D) : (1) the shoreline as it existed 10 years from the date of application, with documentation as prescribed by rule, or (2) the lakeside boundary of the subdivided lot line. (E) (2) The remediation PAL3130 strategy and lessons learns from Slip 2 should serve as a model for future slip remediation efforts in the St. Louis River Area of Concern.