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SR-051573-4A"f,~~y .._ __. j ' f,. r CITY OF SANTA MQNICA . DATE TO: FROM: 5UBJECT ~~ !/' ~(li ,v :~ _ 3 April. 30, 1973 ~ ~`"`"f -.f-~ Perry Scott, City Manager ,!~' ~' ,,, ,, ~~A,. N ,. Doug McAteer, City Engineer ~ ~,~~ -, Annual Street Repair Program ~"" ° 'vY'. We budget funds annually for the repair and maintenance of our streets. This work is performed under private contracts. Part of these funds are made available through the County's "Aid to Cities Gas Tax Program°„ These funds can only be expended on our "Select System of Streets", which is about 75 miles of our more important streets, The amount of these funds has been in the magnitude of $70,000- $80,000 annually. City funds in the approxin~a,te amount of $120,000 have also been budgeted annually for street repair an other than "Select System Streets" -- also by contract work. Therefore, approximately $200,000 is budgeted annually for this type of work to be performed by outside contractors. Our last contract for this type of work was completed on September 8, 1971, at a contract cost of $308,370. This work consisted essentially of constructing about seven miles of concrete gutters; one mile af, con~- cx•ete curbs; .1,000 concrete driveways; and about ten miles of street resurfacing by means of the so-called 01Heater--Remix Method", To my klzowwledge, we did not receive aizy complaints relative to the pavement burning machines used, The "Heater-l~cmix." method consists essentia•11y of: lY After concr=ate guti,e.~~s have been con.stxu ;;ted. (or in tha auc~-1~ thy, z•.treet to a~ resu~:f'accd ryas ca~acrete C;,zt;tersj a '"PAT~'i.i~iGlv1' tiEA T.PJR'~ mac.l~ine i.s uti.lized t;a heat t"rye asphalt pavement 3.n areas where the Date: April 30, 1973 Subject: Annual Street Repair Program ,: Page 2 pavement is too high and must be lowered. (The asphalt pavement should be at least 3/4 of an inch lower than the adjacent concrete, in order to make a proper "butt" join), Directly in back of the heater-machine is a "grader" machine that utilizes a sharp blade to scrape and remove the heated asphalt pavement, 2, After all the required asphalt pavement areas are prepared, as mentioned in "1" above, the "Heater-Remix" method begins, The same pavement heater-machine mentioned above begins heating the pavement in about 10-foot-vaide longitudinal stripse Attached to the bacY. of this heater-machine are a series of "teeth" that scarify the heated pavement, 3. Immediately behind the burning machine is an oil truck equipped with spray nozzles which spray a thin layer of liquid asphalt over the fla Immediately in back of the oil truck is a "Barber-Greene" type asphalt paving machine, which places a layer of approximately 3/4 inch of nevr asphalt concrete aver the scarified and oiled pavement, 5e Immediately after the new asphalt pavement is placed, heavy rolling equipment begins rolling and °ironing" the new pavement, 6. After a period of about tyro or three hours the street can be opened to traffic. For some years, the above mentioned pavement heating-machines have been in violation of the County's Air. Pollution Contral District's (APCD) rules and regulations, but have beery permitted to operate under a variance procedureo In July of 1872, the APCD stated that all req;aests for variances would be denieda I ___ I` Date: April 30, 1973 Subject: Annual Street Repair Program Page 3 Mr. Robert L. Chass, Air Pollution Control officer, recently stated:"The question of using pavement heaters and creating unaccept- able amounts of air pollution versus the use of other non-polluting means which might take longer and be more costly is x•eally the issue and I must insist that the need for clean air is the paramount interest of the citizens of Los Angeles County", Due to the phase-out of the pavement heaters, I have not as yet programmed a city-wide street resurfacing project for 1971-72 or 1972-73. The use of the Heater-Remix process has many advantages over most alternate methods -- except for the fact that it does produce some b ~,A.t;}L'_. ;. Ytl {lkP.. HnWPVPr T tar1iil ri 131ro i-n m..>lrp nn+n ~<" +1.... .c,.. ..+ ti,. _.~ si__ newer burning machines are by no means. the black-smoke-producing "monsters" of about ten years ago. The older machines used an oil type burning fuel. The later models use a liquid propane gas fuel The machines were in violation if they produced a pollutant of black smoke when measured by means of the "Ringelman" test, of a number of one or more, for more than three cumulative minutes in a one-hour period. The vast majority of times the heater-machines were not an violation, but if the machine. went over an oily or "fat" spot in the pavement, the machine would produce a density of smoke more than "11° (on the Ringelrruan chart) for a short period of time until that condition could be correcteda Tn any event, the pavement, burning; machines, at the present time, are not permitted to be used ands therefore, other alternative solutions must be foundm r t~~t. - i ,f <•` Date: April 30, 1973 ~' Subject: Annual Street Repair Program !' Page 4 Prior to mentioning various alternatives, 1 would like to give several advantages of the outlawed burning machines: a. Tn my opinion,' the greatest asset was in the capability of being able to remove a thin layer of asphalt pavement, For instance, if the thickness of an existing asphalt street was six inches and it was desired, for some reason, to remove the top one inch, it was a simple matter to heat the pavement and scrape off the top inch. The cost for this type of removal is about $0.06 per square foot. The only alternative to this method is to completely remave the six inches of pavement and reconstruct the area with five inches of new pavement at a, cost of about $0,50 per square foot -- about 8 times more than the burning process, b. With the heating and scarifying process, new pavement thick- nesses as small as one-half an inch can be laid, This one-half inch is extremely well-banded with the existing pavement, c. The scarifying process reduces many of the small irregularities in the existing pavement surface by "knocking-off" the high spots and filling in the low spots, d. It is a very fast process and does not require the street being torn up and unusable for long periods of time. e. Costs are much less, Depending an the particular instance, the ratio could be bettaeen 2 and 10 times less costly than alternate methods. I would like to preface the following remarks by stating that T am by no means an expert in the i'ield of air pollution, but it does X, ,, r p Date: April 30, 1973 Page 5 Subject: Annual Street Repair Program ,, s° appear reasonable to me that when one compares the total air pollutant problem of the Heater-Remix method versus the alternate method of reconstruction -- the alternate method creates mox•e total pollutants to the atmosphere, but does so legally. For example, let us, take a typical street -- 1 block long (600'); 30 feet wide; the pavement being six inches thick; and has existing 2-foot-wide concrete gutters. Let us assume that in order to join the gutters it is necessary to remove 3/4 inch of asphalt pavement at the gutter edge and varying to 0 inches at 7 feet from the gutter edge, and let us use the contract prices used on the last project. A - HEATER-RENIx Cost: 1200 1.f. Header Cutting ~ 0.38 ....~....... $ 456.00 Heater Remixing = 1733 s.y. @ 0.05 ........ 80.00 hspnalL raving = yu 'cons ~ 11.3u ......... l,uiy.uu Total ......... $ 1,563.00 Construction Time: 4 hours As.r Pollution Problems: The pavement burning machine would probably be in operation for about 4 hours. Of this 4 hours, it might be in violation of the APCD rules for 15 minutes. B - RECONSTRUCTION METEiOD Cost: A. C. Rernovals 14' x 600' x 6" = 155 c.y. c 12,00 ........ $ 1,860.00 New Asphalt Pavement 14' x 600' x b" = 315 tons 12' x 600' x 1° - 45 tons 36o tone ~ 11.30 ........ ~a.yo68.o0 Total ...®..... $ 5,928.00 Time: The street probably would have to be completely closed to traf`z'ic for a per5.od cf ozxe week. t r,., 1 Date: , i~ Subject: ,;` r April 30, 1973 Page 6 Annual Street Repair Program ENVIRONP4ENTAL PROBLEMS: (1) Heavy equipment must be used to break up the existing pavement, (2) Heavy equipment must .be used to load the .pavement removals onto trucks, This causes some dust and noise problems, (3) Trucks must be used to haul the removed material to the County dump. T would estimate 30 truck-trips. to the dump which take approximately one hour for a round-tripo (~-) This also is using valuable dump capacities, Heavy equipment is also used at the dump site to bury this material. (5) The additional 270 tons of asphalt pavement requires that many more tons of our natural resources be used, which includes some additional smog-producing equippment, This 270 tons would also include about 27 tons of liquid asphalt, (6) '_rize additional 270 tons of asphalt pavement must be mixed at a plant, vrhich undoubtedly creates some air pollutants, and then must be transported to the job site in.tx•ucks, Of course, there are other alternatives other than major recon- struction, such as an asphalt pavement "overlay" o£ approximately lz inch thickness, or a "slurry-seal" application,, These types of alternatives are very practical on some streets _ but may not be practical on other streets, In the very near future, 1 am going to propose a street resurfacing program that will probably consist cf a combiratior. of all three pro- cesses: (1) Reconstruction, (2) Overlays, and (3} Slurry-sealing, `, f` Date: f~, Subject; f . r ~ I i ~ %s. 3 April 30,.1973 Annual Street Repair Program Page 7 On April 27, 1973, I had a telephone conversation with a representative of apavement-burning machine company, and he informed me that within possibly two or three months a new type of pavement removal machine - other than the heating type - will be available. I am hopeful, at that time, that we can continue with our past type of street resurfacing program and not pollute the air in doing so. In summary, I would like to say that in my opinion: A. Pavement-burning machines produce less air pollutants than some other types of alternatives. B. One should look at the overall consequences when discussing a certain environmental type problem. C. Without the availability of a pavement removal type machine, . .._......_~ ...,.,...... .. ...,.,..., ....' :.....:.... ...~ +.:~...ii:+~.~~.~..~... ..u ~v-ui~. i.U ua ~iiiuiyi~lu times greater, which either is going to increase the amount of dollars needed, or is going to decrease the rrumber of streets to be repaired. D, b'ortunately, the majority of our streets are in fair to good condition, but vrithaut a good repair program that status will not last for long. L. I am hopeful that an acceptable type of pavement removal machine will become available in the near future. F. There are many different types of situations that I have not attempted to expl.a9xr in this report. Practically every street has a different problem to be considered. Date: April 30, 1973 Page ,8 Subject: Annual Street Repair Program ~ ~', Go I realize there will be many unanswered questions pertain- ing to the subject in question, and I shall appreciate the opportunity to try and explain them in detail9 at your convenience. ~f '"DOUG McATEER City Engineer DM:fs