Laserfiche WebLink
tions, rain may come in contact with the soil material and <br /> hydrocarbon contaminated particles may be washed from the <br /> stockpiles . The Applicant proposes to berm the stockpile <br /> area and install collection sumps at each of the four cor- <br /> ners . In addition, the ramped unloading area will also <br /> drain to a sump. These sumps will collect storm water <br /> runoff and be piped to a wastewater pretreatment system, <br /> which consists of a settling tank, an oil-water separator, <br /> and a dual carbon bed filter. The pretreated storm water <br /> will then be discharged to the Stockton Municipal Sewer <br /> System. (Refer to Project Description for additional de- <br /> tails . ) <br /> The containment , collection and waste water pretreatment <br /> system is proposed to control storm water runoff so that <br /> storm water exposed to the contaminated soil will not flow <br /> off site, or enter adjacent drainage courses . Proper opera- <br /> tion and maintenance of the pretreatment system is a neces- <br /> sary part of this operation. <br /> Mitigation Measures: <br /> a. The contaminated soil stockpile berm should be designed <br /> to retain a 100-year storm condition. <br /> b. The unloading ramp should be constructed of concrete and <br /> designed to collect wash down water and storm water runoff . <br /> Collected water should be ta°eated by a waste water pretreat- <br /> ment system prior to off-site discharge. <br /> C. The contaminated soil stockpile area should be con- <br /> structed to meet the specifications of a Class II Waste <br /> Management Unit as required by Title 23 , Chapter 3 , Subchap- <br /> ter 15 of the California Code of Regulations . <br /> d. A ground water monitoring program, to include up-gradi- <br /> ent and down-gradient monitoring wells, should be implement- <br /> ed prior to project start up, and should be maintained <br /> during facility operations. <br /> e. Contaminated soil transport trucks that enter the stock- <br /> pile area should be decontaminated through a wash-down <br /> process prior to leaving the unloading ramp. <br /> f . The Applicant should obtain Waste Discharge Requirement <br /> (DWR's) from the Central Valley Regional Water Quality <br /> Control Board prior to project start up. <br /> g. The existing on-site well should be destroyed under <br /> permit and inspection by the San Joaquin County Environmen- <br /> tal Health Division. <br /> 20 <br />