First find the volume of the sand in one jug: 2 gallons * 70% = <<2*70*.01=1.4>>1.4 gallons
Then double this amount since there are two jugs: 1.4 gallons * 2 = <<1.4*2=2.8>>2.8 gallons
Then multiply the total volume by the density of sand to find the total weight: 2.8 gallons * 5 pounds/gallon = <<2.8*5=14>>14 pounds
#### 14