products company in houston tex under the product designation 34 super lc 34 which is a curable resin coated proppant applied to crystalline silica sand produced from ottawa type sandstone formations the sand is coated with the curable resin under methods described in u s pat nos 4 518 039 and 4 597 991 the material is applied as described in the literature available from santrol and similar literature about the baker bond product available from baker hughes inteq the slurry 36 is backed by a wiper plug 38 ultimately the volume of slurry 36 is pushed out beyond plug 34 and through the set shoe 28 and into the annular space 30 as indicated in fig1 a predetermined volume is computed so that when the wiper plug 38 bottoms on plug 34 as shown in fig1 the slurry 36 disposes itself outside of the screens 22 and generally up to the area of the stage collar cementing valve 20 additional brine 40 acts as a spacer between the second plug 38 and the third plug 42 the third plug 42 gets caught in the stage collar cementing valve 20 to open up the cementing valve and to close off the tubing string 14 to the screens 22 a cementitious material or other sealing material 44 such as blast furnace slag is then pumped behind the third plug 42 the sealing material 44 enters the annular space 30 above the gravel slurry 36 and goes up and into the casing 12 as illustrated in fig1 at that time a fourth wiper plug 46 is pumped down behind the sealing or cementitious material 44 and eventually bottoms on the stage collar.