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City of South Bend - Schalliol April 21, 2011 Page 4 portions of the assessment. Complete coverage using local street directories, Sanborn Fire Insurance Maps and potentially other historical records regarding the prior uses of the subject site and surrounding properties may be limited, may not be readily available, or may not even exist for purposes of review. SITE RECONNAISSANCE The purpose of the site reconnaissance is to observe current conditions at the site and obtain information indicating the likelihood of environmental concerns with the property. A reconnaissance will be performed for indications of waste handling or disposal activities that may pose a hazard to the subsurface environment. We will require access to all areas, to the extent they are not obstructed by bodies of water, adjacent buildings, or other obstacles. Please note that visual assessment of the existing ground surface will not be possible should there be the presence of extensive snow coverage. As such our assessment of the property grounds will be limited in terms of the presence of stressed vegetation and staining. Unforeseen circumstances notwithstanding, only one (1) site visit will be made. INTERVIEWS Interviews will be conducted with knowledgeable persons to obtain direct, personal information regarding activities and /or operations which may have affected the environmental condition of the site. Selected local regulatory and /or emergency response officials may also be interviewed regarding knowledge of past or present environmental problems or emergency responses at the site. IDENTIFICATION OF DATA GAPS Depending on the availability of certain resources for evaluating historical property use, previous property owners (for interview) and other pertinent information; certain "Data Gaps" may be identified within our Report. Wightman Petrie will make determinations as to the potential impacts such "Data Gaps" have on conclusions as to the presence or potential presence of recognized environmental conditions. PHASE I ENVIRONMENTAL SITE ASSESSMENT REPORTING Upon completion of our site reconnaissance, regulatory database and historical records review, a verbal summary will be presented. Our written report of findings will include documentation to support the analysis, opinions and conclusions found in the report, inclusive of referenced sources. If appropriate, recommendations for additional assessment (Phase II) will be made. Estimated costs and the specific scope of services for performing any Phase II recommendations will be submitted under separate cover. Task 2 — Ground Penetrating Radar Survey Ground Penetrating Radar (GPR) offers the means to detect buried objects that are not otherwise detectable. In addition to the ability to locate metal objects (i.e., underground storage tanks, drums), GPR is able to detect non - metallic objects. The system sends radar pulses into the surface, receives, and processes the reflected energy. Through advanced processing technology, the system calibrates the di- electric constant of the surrounding material. When the signal is reflected from the material having a different di- electric constant, the signal is displayed on the screen as an anomaly. Depth can also be determined by processing the sampling interval and determining the size and comparing relative data to other objects detected. Characteristics of underlying soils effect the penetration of the radar through the ground. Sands and gravel offer the greatest depth penetration and clearest resolution. Whereas, dense saturated clays offer limited penetration of the radar signal. For purposes of this proposal, Wightman Petrie has assumed a depth limitation for the GPR of approximately 8 feet below land surface. Areas of the subject site (exterior only) will be scanned by GPR and delineated using varying interval grid patterns. Multiple scans in a North -South and East -West direction will be performed utilizing the GPR,