Document v6erZQekDworD4mO36zJ2bBdw

CITY OF RAPID CITY SOUTH DAKOTA 57701 In the Beautiful Black Hills PUBLIC WORKS DEPARTMENT ENGINEERING DIVISION 22 MAIN STREET RAPID CITY, SOUTH DAKOTA 57701 X-T/ ' May 4, 1982 Telephone: (60S) 394-4154 Mr. John R. Williams 4005 Chestnut Avenue Fairfax, Virginia 22030 :`s> : s" Re: AWWA C603-78 *T ;. Dear Mr. Williams: Following are my comments relative to revision of AWWA Standard C603-78. I hope they stimulate some meaningful discussion and :fi contribute to the refinement of the Standard. SECTION 1.2 Definitions ; - .* *, "X v ~ . : ' i- 1.2.1 Compacted Backfill The last sentence of this paragraph requires that back fill "shall be placed in not more than 6 in. layers. . ." I believe .{the 6 in. requirement should be eliminated.; Ij;^-i-s^extremely difficult to enforce such a requirement in the field and most contractors will not take the time or put forth the effort to backfill in such small increments. I feel we should be more concerned with the density obtained than the compaction methods utilized. With the development of Nuclear Density Machines, it is relatively simple to check soil densities with a high degree of accuracy. When a particular contractor is aware_ that densities can be determined in a matter of minutes in the field, he will take greater care in backfilling and compacting his trench. If the soil density does not meet requirements, the contractor will be required to compact the backfill by any method necessary to obtain the desired density and still insure the integrity of the pipe.' , SECTION 2.1 Acceptance - fkCE. (, Change the first sentence to read; At the time of delivery to the .job sitej all material. SECTION 2.3 Handling . ...A- Change the second sentence to read: :;U far* n '".Whether moved by hand, skidwaysTThoists", 'or other acceptable) i'.'v - . methods material shall. . . . V. . . . t "I \ . .t------------------------ . Vs.-S^v^CiV.,-v:.: ' : . .r . .v '1 V . CAPCO JEN 0020542 SECTION 3.2 Excavation and Preparation of Trench ,3.2.1 Excavation Methods The third sentence of this paragraph requires that sheeting be "withdrawn in increments of not more than 1 ft." Again, this is a difficult requirement to enforce in the field. I feel we should be concerned with 'the .results rather than the methods used to obtain the results. In addition, situations will undoubtedly arise where sheeting cannot be utilized or where it is impossible or impracticable : to remove it in 1 ft. increments.' Therefore,' this sentence' ', should be generalized to provide for more flexibility. ' For instance, it could be changed to read: .As backfill is placed and sheeting and bracing is withdrawn, it shall be done in such a manner as to not place any stress on or endanger completed work. ... - ' /. The fourth sentence of this section should be changed to read: All excavated material shall be piled in a manner that will . . not endanger the work or the safety of the 'workers and general public or obstruct sidewalks and driveways. , . ' 3.2.4 Excavation in Poor Soil and Refilling to Grade ' - \\ The first sentence should be changed to read: Any part of the trench excavated below grade shall be back filled to grade with compacted material meeting, as a minimum, the requirements of Paragraph 1.2.1. ' .. .. . - Pipe Laid on Trench Bottom or Bedding 2. 6 The.note at the end of this section should list .some recom mended granular beddings and their gradations.-. In lieu of recommending bedding material, ,1 feel the-note should at . ,,.V least recommend the type of materials that are not desirable Pipe Laid on Earth Mounds ` i. v; The first sentence requires that the earth mounds shall be of approved backfill material "compacted firmly." The last sentence requires compaction, ' "to provide a'firm and uniform bedding. . ... . " . , ;. / Again, reference should be made to Paragraph i.2.1 as a minimum. .... ' - '... : ;.- 3.3.2.1 Does this section mean that trench water is allowed to enter V :'the pipe while pipelaying is ' in progress? . f . /'. M* J *l'Vi o "f ("i 1 1 mu 1 n cr o a ntnnooo r Vi /m i 1 ^ Vi n a? v- m -? --v* V* a\ * an 4 4* ^ vn a* ' CAPCO JEN 0020543  m Water shall not be allowed in the trench while pipes are being laid. Water shall not be allowed to rise around . the joint until jointing is completed. 3.3.3 Pipe Cutting Add the following sentence to this section: - Workers shall wear protective clothing and an approved breathing apparatus while cutting and machining the pipe.' 3.5.2 Reference may be made to OSHA Standards. " Reaction or Thrust Backing '* ' ,' ; - . t I'.!' 'V-,/ The third sentence should be changed to read: Hydrants may be tied to the water main with rods, cables, or other devices approved by the Engineer. ' (or manufacturer) 4.3.1 Filling The second sentence should be changed to read: Each section of the pipeline shall be filled slowly with water and all air expelled by means of taps, fire hydrants, or other approved air release devices at points of highest elevation. . Please advise me if you would like more justification of the above , comments or desire that. I use a different format. '/ ; '~t /* SJm - 4" CAPCO JEN 0020544