Laserfiche WebLink
KOPPEL-STOCKTON TERMINAL <br /> Monitoring Well Installation Work Plan <br /> The Koppel Stockton Terminal(Koppel) is a former dry fertilizer warehouse.The site is <br /> located in Stockton west of Ventura Avenue,between the extensions of Hazelton Avenue <br /> and Sonora Street,approximately 1 mile west-southwest of the I-5/Highway 4 interchange, <br /> next to the Port of Stockton,California. The site layout of the Koppel Stockton Terminal is <br /> presented on Figure 1. <br /> Phytoremediation is being used to remove nitrogen from soil and groundwater at the site. A <br /> test grove of 267 poplar trees was planted on approximately one acre on the southern end of <br /> the site in May 1998 to evaluate the effectiveness of phytoremediation.An additional 1,250 <br /> hybrid poplar trees and 230 willow trees were planted in the vicinity of the turnaround area, <br /> stormwater pond,former bagging plant,and in the area north of the warehouse during <br /> March through June 2000. <br /> At the request of the Regional Water Quality Control Board (RWQCB) (RWQCB 2004), <br /> CH2M HILL is submitting this Monitoring Well Installation Work Plan for the installation of <br /> one monitoring well(KP-10S)north of the site. This report includes the following <br /> information: <br /> • Rationale for well installation <br /> • Description of well drilling procedures <br /> • Description of well construction and development <br /> • Schedule for installation and sampling <br /> 1 .0 Rationale for Well Installation <br /> Twelve flinch-diameter monitoring wells and five 2-inch-diameter piezometers have been <br /> installed at Koppel between 1996 and 2000(CH2M HILL,1996;CH2M HILL,1998; <br /> CH2M HILL HILL,1999;CH2M HILL,2000).Water quality data have been obtained from <br /> these monitoring wells and piezometers quarterly between 1996 and 2000 and semi- <br /> annually between 2000 and 2004.As a result of the sampling,data trends have been <br /> established for most wells onsite.Data trends show reductions in nitrate concentrations in <br /> shallow groundwater in the vicinity of the original poplar test grove area.In addition, <br /> nitrate concentrations downgradient of the original poplar test grove are relatively low, <br /> indicating that natural attenuation is occurring. <br /> The former Cal Farm Supply facility is located north of the Koppel Stockton Terminal <br /> (see Figure 1).Nitrate-nitrogen concentrations in groundwater collected between 1997 and <br /> 1999 from Cal Farm Supply's southernmost monitoring well,MW-6,ranged between 216 <br /> and 367 milligrams per liter(Karsyn,2004). These concentrations are closer in magnitude to <br /> Koppel's proximate well,KP-2 (see Figure 1),than nitrate concentrations detected in other <br /> ROMA320184WEPORT812004_MONRORINGWELLWP12004_MWELLWP.DOC 7 <br />