P. R. Parker Company, Inc.

One of several tandem dump trucks with identical dump beds

 
New 4,200 gallon Bearcat distributor mounted on new Freightliner truck - one of the Company's three high capacity, high-tech Computer Rate Controlled distributors

 

Bearcat chip spreader - one of two of the Company's state of the art Computer Rate Controlled chip spreaders

 

Small two-barrel box culvert with parallel wing-walls constructed in San Jacinto County, TX

FREQUENTLY ASKED QUESTIONS
OUR WORK AND ACCOMPLISHMENTS
  Did your company work in Nebraska?
  Did your company apply an asphalt surface treatment at night?
  Did your company apply a chip seal out of season during December?
  Does P. R. Parker Company still build bridges?
GENERAL PAVEMENT QUESTIONS
  What is Chip Seal/Asphalt Surface Treatment?
  Can I save my parking lot {driveway or street} with an asphalt surface treatment?
  Can I save money by resurfacing my asphalt pavement with asphalt surface treatment?
  What is a Fog Seal?
  Why has the asphalt on my parking lot {driveway or street} deteriorated and failed?
  My asphalt pavement has many small cracks - is it too late for a fog seal or asphalt surface treatment?
ASPHALT SURFACE TREATMENT (includes technical questions)
  What is "Tracking" ?
  What is "Bleeding" ?
  What is the difference between Emulsion and Hot AC?
  How do you know when to adjust the asphalt rate on an asphalt surface treatment?
  How do you know the computers on your distributors are correct?
  Your staff said the dark color of the wheel paths (tracking) was due to not enough emulsion - explain?
  What is the lowest temperature that emulsion may be applied?
  Can No. 7 Stone be substituted for LADOTD Size 2 for asphalt surface treatment?
  What are some sources for Chip Seal aggregate in Louisiana?
  Can an asphalt surface treatment be applied directly onto base or does it have to first be primed?
  What is a distributor calibration?
  What is a spray bar test on a distributor?
  What is the difference or relationship between Embedment and Asphalt Rate?
  Which state DOT has the best specifications for Asphalt Surface Treatment?
  What are the Asphalt Surface Treatment sections for other State DOT Specifications?
GENERAL & MISCELLANEOUS QUESTIONS
  Is it true that your company only purchases Ford vehicles?
  Should a county, parish, town or city self-perform asphalt surface treatment?
  Do contractors have to pay sales tax on materials used on projects for a tax-exempt entity?
  I accidentally drove through your work area and got tar on my car, how do I get it off?
  Why does your company let people drive so fast in your work zones?
  My windshield was broken on your project, what is the procedure for having it replaced or repaired?
  What is a box culvert? / what is the difference between a box culvert and a bridge?
  Why doesn't P. R. Parker Company mark up subcontractor's prices?
  How can a subcontractor get established with P. R. Parker Company?
  How do you estimate so closely the amount of rock left in a stockpile?
  Is your company Union or Open Shop?

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Q. What is "Tracking" ?
A. Tracking occurs when tires come in contact with uncured emulsion and it sticks to the tires and then is transferred to the top of the aggregate in the wheel paths giving a dark appearance to the wheel paths.  Tracking will always polish off (wear off) in time.  Tracking is typically caused by too much aggregate and by allowing traffic to stop or move very slowly on an un-cured emulsion.
   
Q. What is "Bleeding" ?
A. Bleeding is quite possibly the most misused term in all of asphalt surface treatment.  Bleeding is different from "Tracking", but tracking almost always occurs where "Bleeding" is present.  Bleeding is when the level of the asphalt is very near or above the top of the aggregate.   Bleeding can be a result of: too much asphalt, too much aggregate, breakdown or crushing of aggregate, or aggregate being pushed into a soft surface below.  The latter may occur at any point in time even long after application.  Bleeding is usually only a problem during very hot weather. 
   
Q. Which state DOT has the best specifications for Asphalt Surface Treatment?
A. My personal favorite is Texas with a little bit of Oklahoma sprinkled in.  Texas is second only to California in the volume of Asphalt Surface Treatment used, but we have not worked in California.  Although there are often more ways  than one to accomplish something, there is always only one best way.  So it is a mystery why there are so many differences between the specifications of various states.  An example would be: If Louisiana were to adopt Oklahoma's allowance of applying emulsion on wet pavement, it would create more work days each season which would spread equipment depreciation over more work days and in turn yield lower costs to taxpayers.   
   
Q. I accidentally drove through your work area and got tar on my car, how can I get it off?
A. The black substance on your vehicle is probably Liquid Asphalt which is a product made from crude oil.  It will not harm your car or the paint.  But the sooner you get it off the easier it is to get it off.  For a quick fix use WD40 and a rag.  Most commercial cleaners from an automotive store that claim to remove tar should also work.  There is no reason to remove it from the underside of the vehicle, as we have been told it is similar to commercially applied asphalt-based undercoating.
   
Q. Is it true that your company only purchases Ford vehicles?
A.  YES, unless what we need isn't available from Ford.
 

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Q. What is Chip Seal/Asphalt Surface Treatment?
A. Asphalt Surface Treatment, also known as Chip Seal, is a process where pure Liquid Asphalt is distributed over an existing pavement or newly prepared base course and then Aggregate is spread over the asphalt before it cures.  The surface is then rolled to seat the aggregate.  Once the asphalt has cured, any loose aggregate may be swept away leaving a new driving surface that seals out all moisture.  The asphalt seals out water and the aggregate carries the traffic and prevents tires from coming in contact with the asphalt.  Asphalt surface treatments are an important step in most successful pavement preservation programs where a hot-mixed asphalt surface gets a life-lengthening asphalt surface treatment to renew and extend its life for several years.       
   
Q. Why has the asphalt on my parking lot {driveway or street} deteriorated and failed?
A. Most people do not understand what causes pavement failures.  The chief cause of pavement cracking, rutting, and potholes is moisture that seeps into the base and sub-grade through cracks in the surface.  When hot-mixed asphalt ages to the extent that it becomes brittle, cracks develop and then moisture sneaks in.  The base and sub-grade below the pavement surface are what supports the weight of traffic (not the pavement surface) and it must not yield.  Moisture acts as a lubricant between gravel, soil and other earthen particles in the base and sub-grade which promotes movement when traffic rolls over.  The typical process occurs first by the development of very small cracks which allow moisture in, then once the material below the surface starts to move, the surface begins to break showing larger cracks (allowing even more water in), then alligator cracking typically occurs, then potholes and rutting - then all is lost.  All because of moisture.
   
Q. Can I save my parking lot {driveway or street} with an asphalt surface treatment?
A. If your pavement structure has not yet failed, an asphalt surface treatment will certainly extend the life of your pavement structure by preventing the dangerous infiltration of moisture below the surface while at the same time provide a new uniform driving surface.  But if your pavement has already started to fail in isolated areas, those failures will require repair and patching prior to the application.
   
Q. Can I save money by resurfacing my asphalt pavement with asphalt surface treatment?
A. Absolutely. Asphalt surface treatment is the very best way to seal your existing asphalt pavement while providing a beautiful and durable new driving surface.  We believe that every dollar spent on pavement preservation now will save approximately ten dollars in pavement rehabilitation or reconstruction in the future.  TXDOT (Texas Dept of Transportation) seems to have a goal of applying a new asphalt surface treatment to many of their roads approximately every five years.
   
Q. What is a Fog Seal?
A. A fog seal is a light application of emulsified asphalt to renew an old pavement surface.  Fog Seals are used to seal small cracks, increase aggregate retention, rejuvenate and add a uniform dark new color to old pavement.  A slow setting emulsion is distributed over the pavement surface and left to "break" and cure.  Once the water and asphalt separate, and depending on temperature, wind and humidity, the surface is usually ready for traffic within a few hours with a beautiful new water-tight surface.  Fog Seals are used as an additional step in more sophisticated pavement preservation programs where often hot-mixed surfaces get a life-lengthening asphalt surface treatment, and then often the surface treatment gets a fog seal after a while to extend its life as well.  Fog seals are also applied directly over less aged hot-mixed asphalt surfaces in some cases prior to the inevitable development of small cracks.       
 

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Q. My asphalt pavement has many small cracks - is it too late for a fog seal or asphalt surface treatment?
A. Tiny cracks often begin to appear in hot-mixed asphalt surfaces as early as six months after installation.  And some agencies will apply a fog seal when these are first detected.  Usually a Fog Seal will handle cracks smaller in the range of one thirty-second of an inch in width.  A one course asphalt surface treatment will usually handle cracks of up to approximately one quarter of an inch in width.  And a second course of asphalt surface treatment may be required for wider cracks or if cracks are still visible after the first course, or wider cracks could be sealed prior to resurfacing. 
   
Q. How do you know when to adjust the asphalt rate on an asphalt surface treatment?
A. The easiest way to consider an asphalt surface treatment is to think of a saucer partially filled with water and some marbles.  If the saucer starts out with 1/2 inch of water and a single marble with a diameter of one inch is dropped in, the water will come up about 1/2 inch on the marble.  But if you continue to add marbles, the water level will rise nearer and nearer to the top of the marbles with each additional marble.  Just as the water rises on the marbles, so will the liquid asphalt rise nearer the top of the aggregate of an asphalt surface treatment.  If the asphalt rises high enough, the tires of vehicles may reach down and touch it.  When this happens, the asphalt may stick to the tires and "tracking" may occur - and possibly something worse.  So if you desire to have more rock, the asphalt rate must be reduced.    So it is usually considered good practice to start out light with the asphalt and aggregate and slowly increase the aggregate rate until the desired rock appearance is reached, then tweak up the asphalt rate to match.  If the rock rate is increased - the asphalt rate must usually be decreased, but remember the chief purpose of the rock is to prevent tires from coming in contact with the asphalt which is there to seal out water.  So be sure there is plenty of space between the aggregate.  A wise old TXDOT inspector once told me, " a quarter should easily fit between the rocks when laying flat on the asphalt of a chip seal."
   
Q. What is the lowest temperature that emulsion may be applied?
A.

Almost every state department of transportation has specific seasonal requirements restricting the application of asphalt surface treatments, and most also have specific temperature ranges that may override those calendar date restrictions.  With so many different rules, P. R. Parker Company decided to experiment and find out what the real limits are for CRS-2P emulsion.

We started at 55° and rising, and worked our way down in 5° increments.  We had success at 45° and rising, with a low temperature of 38° the following night.  The morning of the application, the temperature rose to 45° at 10:20 a.m. at which time we began the application which was completed by 12:00 noon.  The temperature continued to rise following the application to a high of 61° for the day, and then fell again that night to a low of 38°.  We waited until 10:00 a.m. the next morning to sweep the area, and all was good.  When we then performed an application at 40° and rising - we experienced some minor aggregate loss in some small isolated patches.  It should also be noted that during these experiments, no traffic was allowed on the surface prior to sweeping.

 

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Q. Your staff said the dark color of the wheel paths (Tracking) was due to not enough emulsion - explain?
A. When there is not enough liquid to hold larger aggregate firmly in place during curing, it can be rolled over by traffic which causes the individual rocks to become coated.  This coating of the rock robs even more asphalt away from the road surface where it is needed to seal the road and hold the rock.  You indicated that you were an LADOTD Engineer (you are the 4th to ask this), so with all due respect, the general mindset of the day within LADOTD seems to be, "what is the least amount of asphalt required to hold the rock", while the practice in Texas and other states with long histories in asphalt surface treatment is, "we are here to seal the road so we want as much asphalt as possible".  If your road is perfect with no cracks, it can easily take 0.41 gallons of CRS-2P per square yard with a Size-2 aggregate - if there is any cracking at all then the asphalt rate must be increased.
   
Q. Can No. 7 Stone be substituted for LADOTD Size 2 for asphalt surface treatment?
A. Absolutely not!  Although the gradations are identical on the No. 8 sieve and above, the stone must be washed.  Any amount of material passing the No. 8 sieve is not useful for the intended purpose of the aggregate, and anything smaller than the No. 16 sieve is detrimental to a successful application.  Only washed stone should be used for chip seal aggregate.  We have found that any dirt, dust, silt or clay can form a film (much like flour in the kitchen) around the aggregate that works to prevent the rock from adhering to the asphalt.   
   
Q. What are some sources for Chip Seal aggregate in Louisiana?
A. Although there are no natural sources of which I am aware, there are some good sources if you stay with LADOTD and TXDOT specifications.  Crushed stone that meets the friction ratings for all Types is available from Martin-Marietta's Jones Mill Quarry via truck or rail on the Union Pacific.  Crushed stone that meets a friction rating III and under is available from Granite Mountain Quarry via truck or rail on the Union Pacific.  Lightweight aggregate that meets all friction ratings is available by truck from TXI's Streetman, TX Plant, or Big River Industries' Erwinville Plant.  I would suggest that all designs allow TXDOT Grade 4 as an approved equal for LADOTD Size 2, and TXDOT Grade 5 as an approved equal for LADOTD size 3.  This will allow for the best economics.  TXDOT Grade 4 will easily meet the specifications of LADOTD Size 2.
   
Q. Did your company work in Nebraska?
A. Yes we first went to Nebraska in 2008 to apply a fog seal on I-80 and I-880 near Lincoln, NE.  The NDOR (Nebraska Department of Roads) project consisted of 328,900 gallons of slow setting emulsion, some of it applied at night, and we where there for four weeks performing the work.  We returned to Nebraska again in September of 2010 to apply another nighttime fog seal near Lincoln.  The NDOR specifications are very clear and reasonable, and we intend to do more work in Nebraska in the future.
 

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Q. What are the Asphalt Surface Treatment sections for other State DOT Specifications
A.
Caltrans California, Section 37 http://www.dot.ca.gov/hq/esc/oe/specifications/std_specs/2006_StdSpecs/2006_StdSpecs.pdf
LADOTD Louisiana, Section 507 http://www.dotd.la.gov/highways/project_devel/contractspecs/2006_Part_V-Asphaltic_Pavements.pdf
MDOT Mississippi, Section 410 http://www.gomdot.com/Divisions/Highways/Resources/Construction/pdf/2004StandardSpecs/division400.pdf
NCDOT North Carolina, Section 660 http://www.ncdot.org/doh/PRECONSTRUCT/ps/specifications/english/s660.html
NDOR Nebraska, Section 515 http://www.nebraskatransportation.org/ref-man/specbook-2007.pdf
ODOT Oklahoma, Section 403 http://www.okladot.state.ok.us/c_manuals/specbook/2009specbook.pdf
TXDOT Texas, Section 316 ftp://ftp.dot.state.tx.us/pub/txdot-info/cmd/cserve/specs/2004/standard/s316.pdf
   
Q. Why does your company let people drive so fast in your work zones?
A. That is an interesting question.  We have requested various law enforcement agencies to please come and spend some time in our work zones hoping their presence might influence motorists to slow down.  But not once have any agreed to do so, so we eventually gave up and stopped asking.  We are not permitted to change the speed limits.  We are only allowed to post construction signs that are shown on the plans.  Several years back, Louisiana DOT allowed us to use a pilot car as had been the practice in Texas for many years, and now pilot cars are required on most Louisiana chip seal projects.  This has been a great help in reducing speeds and windshield damage.  It seems that law enforcement does not consider our work zones as open-public-roadway.  Much of our construction equipment and vehicles operating within our work zones are "unlicensed" and are typically hauled to the project on trailers.  This may be one reason law enforcement stays clear of our work zones.  All we can really do is post flaggers at each end of the work zone, operate a pilot car, and say, "please slow down for your own, and everyone's safety".   
   
Q. How do you know the computers on your distributors are correct?
A. The tank of each P. R. Parker Company, Inc distributor is calibrated in accordance with Texas Department of Transportation (TXDOT) testing procedure (TEX-922-K).  Each distributor is then periodically verified throughout the life of the distributor the results of which are certified and stamped by a Licensed Professional Engineer.  This certification guarantees the owners of our projects that they are receiving the quantity of asphalt product for which they are paying and it guarantees us that we are being paid for the proper quantities.  The data collected while performing the TXDOT procedure has also been suitable for preparation of all other tank certifications we have encountered to date.
   
Q. Did your company apply an asphalt surface treatment at night?
A. Yes, we first applied an asphalt surface treatment during a nighttime operation on I-49 between Opelousas and Lafayette, Louisiana.  It was decided that it would be safest to perform the work at night due to high traffic volumes.  During the hours of 7:00 p.m. and 6:00 a.m. traffic was channeled into one lane northbound and one lane southbound while we applied the one-course surface treatment within the lane closures.  According to LADOTD (LA Dept of Transportation & Development) personnel, this was the first time an asphalt surface treatment had been applied at night in Louisiana.   
 

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Q. Did your company apply a chip seal out of season in December?
A. Yes, we applied an asphalt surface treatment during December on an experimental LADOTD  project extending past LA 494 near the Kisatchie National Forest.  LADOTD was experimenting with the use of reclaimed asphalt pavement mixed with a rejuvenating agent as a paving surface course which was placed over an asphaltic surface treatment which was placed over a newly milled surface.   
   
Q. How can a subcontractor get established with P. R. Parker Company?
A. The first step is to be properly insured, which means having coverage and limits at least equal to what we are required to have as a prime contractor by the owners of our projects.  The next step is to bid on our work.  We take great pride in the fact that we award to the subcontractor who was low bidder on bid day. 
   
Q. My windshield was broken on your project, what is the procedure for having it replaced or repaired?
A. We do not replace or repair damaged windshields on vehicles that we do not own.  We are required by the Department of Transportation to place "loose gravel" signs in our work zone and we are not allowed to begin work until State DOT representatives have confirmed the placement of required signs.  We are not at liberty to do any more than that, such as change the speed limit, although irresponsible speeds are typically the cause of windshield damage.  Most windshield damage occurs when one vehicle passes another traveling in the opposite direction while one or both are traveling at speeds greater than 25 mph.  Speeds of 25 mph and less, no matter what the posted speed may be, are usually adequate to prevent debris from being throw up that might damage your vehicle or those of others.  Your own insurance provider is the best avenue for road hazards of this type.
   
Q. Why doesn't P. R. Parker Company mark up subcontractor's prices?
A. When we turn in our bid to the owner we will typically bid the exact unit prices quoted to us by the subcontractor whose prices we used.  This allows all subcontractors to immediately know, when viewing the owner's bid tabulations, whether or not we used their price, and to have confidence of complete confidentiality on bid day when they give us a quote.
 

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Q. How do you estimate so closely the amount of rock left in a stockpile?
A. The key is consistency of stockpile housekeeping.  All stockpiles should be constructed neatly and then reshaped at the end of each shift back to its original configuration (i.e. conical if it was originally conical).  A simple "T" made from two pieces of  2 x 4 lumber of known lengths can then be used with a camera to quite accurately estimate the volume of the pile.  Stand the "T" at the base of the pile and take a picture of a new stockpile.  Print the picture and use the known lengths of the "T" to prorate the dimensions of the pile.  Then use these dimensions with the original know tonnage as a ratio with later dimensions to estimate the remaining volume. 
   
Q. Does P. R. Parker Company build bridges?
A. No, we have never built a bridge, but we have installed or constructed box culverts that may resemble bridges.  These projects are often called "bridge replacements" by the owning agency, but of these projects that we have completed any old bridges were replaced with new box culverts.
   
Q Can an asphalt surface treatment be applied directly onto base or does it have to be primed?
A. Although we do not recommend it, we have successfully applied two-course asphalt surface treatments directly onto completed sub-base without a prime on the surface.  When attempting this shortcut, the base must be kept moist, and the first course must be emulsion, and a second course has always been necessary.  Emulsion is well suited to wet conditions, and bases/sub-grades must be kept moist to prevent unraveling prior to the application, so the two go hand-in-hand.  It is certainly better to prime a base prior to application, but when it is impractical or unfeasible, it is "possible" to skip the prime and still achieve success.  The bottom course should be cured with no traffic allowed, but if traffic must be allowed on the tender surface while curing, be prepared to patch bare spots that typically develop in the wheel paths.  The first examples of this process in which we were involved, occurred in north Louisiana when newly cement-treated base needed to be cured under traffic.  Since prime courses do not stand up for long periods under traffic, LADOTD decided to attempt a two-course asphalt surface treatment directly and immediately over a newly-placed cement-treated base to provide a curing membrane and driving surface at the same time.  It worked and held great once the top course was in place, but sometimes the wheel paths in the bottom course got quite spotty and bare, but after patching and applying the top course, everything was fine.  Those first applications where later covered with a hot-mixed asphalt surface, but now second courses of asphalt surface treatment are successfully being used as the final driving surface in Louisiana just as they have been for years in Texas.     
 

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Q. What is the difference between Emulsion and Hot AC?
A.

There are basically two types of liquid asphaltic materials that we regularly apply: Emulsions and Hot AC (Asphaltic Cement).  Although both types do an excellent job at sealing, each has different characteristics when it comes to application.

Emulsions such as CRS-2P are generally considered to be  excellent at aggregate retention once they properly cure and set up, but it can take several hours or more to set up.  Emulsions are therefore excellent for new construction, city and county streets,  parking lots or other situations where traffic can be eliminated or minimized until properly cured, only after which sweeping can take place.  But when traffic (especially higher speed) must be allowed on a surface on the same day of application, things quite often get messy with emulsions, and this is aggravated increasingly as daytime temperatures rise.  Perhaps emulsions best characteristics are its good performance with lower surface temperatures and they may be applied over wet surfaces, and with wet aggregate, so this means more application opportunities.  {good with: low temp, damp surfaces} {not so good with: high temp, immediate high traffic}

Hot AC such as PAC-15, AC-15P, AC-20-5TR, and many others set up very quickly and can usually be rolled, completely swept and open to traffic almost immediately.  This makes ACs a favorite among contractors and engineers for resurfacing higher traffic and/or higher speed roads.  Hot ACs with their fast setup and higher softening points are very high production and less messy for top courses and resurfacing under traffic than are emulsions.  AC may not be applied on wet surfaces and it is more limited by cooler surface temperatures than emulsions, so this means more limited application opportunities. {good with: high temp, immediate high traffic} (bad with: low temp, wet surfaces}

   
Q. What is a distributor calibration?
A. A distributor tank calibration is a test required by TXDOT to insure that the computerized onboard metering equipment is working correctly.  As described in TXDOT TEX-922-K, we have an Asphalt Distributor Tank Calibration Test (Section 2, Part I) performed on each of our new distributors with the resulting metal strap mounted onto the driver's side of the tank.  Then every four years we employee a Licensed Professional Engineer to oversee an Asphalt Distributor Tank Verification Test (Section 3, Part II) to insure that the strap remains correct.  A typical  Tank Verification Test usually consists of a few check points near the bottom, a few near the midpoint, and some near the top.  This will verify or construct data arranged in either 25 or 50 gallon increments within allowable tolerances.  The testing procedure leaves the actual number of check points up to the attending Engineer.  
 

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Q. What is a spray bar test on a distributor?
A. A spray bar test or calibration is a test to insure that the rate of asphalt metered out by a distributor's onboard computer, is being evenly distributed transversely across the surface.  As described in TXDOT TEX-922-K we annually Employee a Licensed Professional Engineer to perform an Asphalt Distributor Spray Bar Test (Section 4, Part III) on each of the Company's distributors with a written and stamped report for our TXDOT work.  Our personnel performs the same procedure several times each season sometimes using volume instead of weight, if water is used.  We use containers manufactured by TUPPERWARE® each having the exact same dimensions and we follow the procedures outlined in ASTM D 2995 (2009) for our LADOTD work which yields the same results as TEX-922-K, Section 4, Part III. We line our containers with plastic bags if we are not testing with water, this is easier than cleaning them. Engineers representing our customers may request a copy of a recent calibration.
   
Q. Does a contractor have to pay sales tax on materials in Louisiana used on a project for a tax-exempt entity?
A.

This is a very good question and one of which the answer will either save or cost the owning entity much money and/or change the outcome of what would otherwise be a fair competitive and "legal" public bidding process.  Perhaps even more interesting is the question of whether federal funds granted or otherwise distributed to parishes or towns for the purpose of "constructing or improving roads" can legally be diverted to other uses via sales taxes charged on materials going into such "construction or improvement of roads".

Generally a contractor acting as an "agent" of a tax-exempt owner should not be required to pay sales tax on materials (moveable property) purchased and temporarily entered into inventory for later incorporation into the project (final product/immovable property) which is in the end sold to the owner (end user) after complete fabrication from materials the owner supplied himself through his agent. But for this to occur, the "agent" relationship MUST first be in place by completing Form R-1020 as described in Form 1020 General Information.  Reference: F. Miller & Sons v. Calcasieu School Board, 838 So.2d 1269 (La. 2003).  

 

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Q. What is the difference or relationship between Embedment and Asphalt Rate?
A.

 

The asphalt "Rate" is the exact gallons of asphaltic liquid distributed/sprayed over a given area, The "Embedment" is the depth of the residual asphalt as a percentage of the average height of a single piece of aggregate.  So, a 40% embedment on a 1/2" aggregate would represent a depth of 0.20 inches of residual asphalt.  Although it may at first seem like a simple task to calculate the embedment from a given rate, or vise versa, there are several things that must be considered that will drastically complicate things.

We know that one Square Yard (SY) is 36" x 36" or 1,296 Square Inches, and we know that there are 231 Cubic Inches in one Gallon (Gal).  So mathematically we can determine that a rate of 0.40 Gal/SY yields a liquid depth of 0.0713 Inches in an area of one SY.  And if a single piece of aggregate is 1/2 inches in diameter, then we see that this appears to be an embedment of about 14%.   Now we cannot forget that this depth of 0.0713 Inches is "before" the addition of aggregate: which will displace some amount of liquid, and in turn increase the depth of the liquid, which will increase the embedment.  Also any cracks in the existing surface will drink up some of the liquid.  Now you see why I said it can get complicated.  Aggregate size, shape, gradation, and amount, as well as surface cracks, all effect embedment and rate, as well as asphalt to water ratios when dealing with emulsions.

   
Q. What is a box culvert/what is the difference between a box culvert and a bridge?
A. A Box culvert (bottom picture in top section) is a concrete drainage structure with a rectangular section that is constructed from the ground as opposed to bridge construction which typically requires above-ground operations.  A box culvert may be used to replace a bridge in many applications.  A concrete box culvert is typically constructed by one of two methods:  precast or cast-in-place concrete.  A precast box culvert is constructed by placing fully completed precast sections on a prepared sub-grade, much like laying concrete pipe.  A cast-in-place culvert is constructed in up to three phases: (1) floor or foundation, (2) Walls, (3) Top, with all of this work being done from the ground.    
 

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Q. Should a county, parish, town or city self-perform asphalt surface treatment?
A.

We have performed work for local governmental agencies that have their own asphalt surface treatment equipment.  The reasons we have heard they call us are: lack of expertise, lack of production, cost concerns, and unsatisfactory results.  Our operators apply asphalt surface treatment every day and that is all they do.  A county or town would have to perform approximately $10,000,000 of asphalt surface treatment each year for their employees to equal that much hands-on experience, but most only spend a fraction of that.  Typically county employees perform many different types of work in a year and only spend a minimal amount of time performing asphalt surface treatment.

Any taxpayers would almost certainly agree that all work should be performed by contractors if allowed to see the real difference in cost, and if for no other reason, there is the guarantee of proper performance provided by the contractor's bonding: http://www.sio.org/html/why_bonds_reqd.html

One of the most, successful County/Parish pavement programs I know of is that of Bienville Parish, Louisiana.  Their own forces have become experts at patching and base work, while they contract out the final asphalt surface treatment.  Their current Road Superintendent is very knowledgeable in the area of asphalt surface treatment, and could certainly manage the chip seal work.  But he and the Bienville Parish Police Jury stretch their dollars over the most miles of road by being experts at a few important operations instead of attempting to be jacks-of-all-trades.  Annually Bienville Parish accepts bids for an asphalt surface treatment project in the $1,000,000 range.  Their forces then prepare new and existing roads all over the parish to be surfaced.  Then the contractor is released to apply asphalt surface treatment, and their roads are among the best in all of Louisiana.

   
Q. Is your company Union or Open Shop?
A. P. R. Parker Company is Open Shop, Non-union, and does not support socialism or discrimination in any form, and the Company itself is a product of free enterprise, a chief principle on which these United States were founded. 
 

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