Cy EXCAVATION BELOW THE LEVEL OF PIPELINE ROAD. Excavations below the established level of Pipeline Road are tnrasible and would have the following advantages and disadvanteges: Agvantages Such excavations, which would probably be a source of excellent gravel, could form attractive lakes, as provided for in the LaFarge Agreement, Could serve as settling basins for an interim period acd as such be gradually refilled with the silts and clays not required in the operation. 3. They could be backfilled as in the form of a dump for unwanted or substandard natural materials. Disadvantages See i. The necessity to remove gravel under water. 2. Washouts could negate the use of these excavations as settling basins. If these excavations are to be retained as artificial lakes, then there would have to be an adequate water supply to prevent stagnation, Should construction ever be anticipated in the area of any of these lakes that have been filled by settled solids or backfill material, then the definite possibility of foundation problems would have to be anticipated, Where an operator wishes to excavate below the level of Pipeline Road, it is recommended that thia be done at the Giscretion of the Engineering Supervisor and that authority be given by writing on the submission of location plans prepared by a suitably qualified professional engineer. De. RECLAMATION OF THE GRAVEL PIT AREAS. The existing bylaw does not seem to contain definite requirements for reclamation, Tt is suggested that By-Law 1489 be revised by adding the following subsection: -~6- “Section 6(h}, The fi1rished slopes of the areas affected by the sori removas shall be such that the Slopes will be stabte, but in no case shall the slopes be greater than one (1} Zoot rise in one and one-half (14g) Jeet of run, with fifteen (15) fect wides benches at fifty (50) fret vertical intervals, The surfaces of ureas affected by the soil removal should be reclaimed such that the surface 3s completely coveree by a blanket of soil net less than eight (8) inches thick, which will support Growth of grass and trees to the standard defined in this Section 6(hi. This blanket of soil, which nest Le stuble, may be composed ‘Gil native to the area, cariched Sy addiction of fertilizer. Grass and trees shal} be firmaly estadlished in the areas being reclaized to the setistaction of a responsible District of Coquitlam authority”. In order that the landscaping provisions be net by a gravel pit operator when the operation is terminated, either after all allowable gravel removal is Couple cd or if the operator dis- continues his operation before all pessible gravel has been removed (the latter case occurring if the quality of the material to be excavated makes the operation uneconcmical, or if the Gperation ceases for any other reason before ultimate gevelopeent}, the gravel pit operator should be required to furnish us with « Suitable Performance Bond. It is therefore recommended that By-Law 1459 de revised by adding the following subsection: “A good and sufficient bond under seal by the applicant shail Cause land restoration works to be effected to a standard cf Eight Hundred (800) trees per acre being apportioned by aunxber as follows: One Hundred and Sixty (160) Douglas Pir (Pseudo Tsuga Bouglasi) per acre, One Hundred and Twenty (120) Hemlock (Tsuga Heterophylia) per acre, : Eighty (80) Red Cedar (Thuja Plicata) Forty (40)vine Maple (Acer Circinatum) per acre Pour Hundred (400) Red Alder (Alnus Rubra) per acre, and Seventy-five (75) lbs. of evenly mixed grass seed per acre to consist of: Creeping Re@ Fescue- Twenty (20) lbs. per acre, Hard Pescue - Twenty (20) lbs. per acre, Perennial Rye Grass - Twenty (20) lbs. per- acre, Annual Rye Crass - Ten (10) lbs. per acre, Crown Vetch ‘> Five (5) lbs. per acre, and in accordance with the said vermit and this By-law and performance hond acceptable to the Engineering Supervisor, the principal amount of Two Thousand Five Hundred Dollars ($2,500.00) per acre of the areas affected by the sorl vemoval permit {such areas to include excavation areas, Purification facilities, storage arcas, work areas, stockpile 7