Check your proposed seepage pit location to conduct a preliminary screening to determine whether the surficial geologic unit meets the rule requirement for siting within valley-fill sediments in a basin-and-range alluvial basin.

Enter the latitude and longitude in decimal degrees or degrees, minutes and seconds, then click Submit. Coordinates must be within Arizona and should be as accurate and precise as possible for the parcel location. The large-scale map used in this tool contains inherent boundary uncertainty at site scales and may not be accurate for all sites. You should review other best available maps at closer scales (100K, and preferably 24K) and a site-specific evaluation should be used to confirm the surficial geologic units at the site scale.

R-18-9-A311(B)(1)(2) - A person may install a seepage pit only in valley-fill sediments in a basin-and-range alluvial basin and only if the seepage pit performance test results meet the criteria specified in R18-9-A312(E). The person shall specify in the Notice of Intent to Discharge that no limiting conditions described in R18-9A310(C) and (D) were identified at the site.

This high-level map is presented as one possible screening-level tool to evaluate whether the proposed seepage pit location may be within the requirements specified in R18-9-A311(B). It is possible that ADEQ may require additional sources of data to demonstrate compliance because of map or other limitations.

This map is based on a digital version of AZGS Map 35 at a scale of 1:1,000,000. To reduce the likelihood of false negatives — where a location is incorrectly identified as being outside a required formation — this analysis incorporates a horizontal error buffer. Because the source dataset was compiled at a 1:1,000,000 scale, it carries an inherent horizontal positional error of approximately 508 meters (1,667 feet) based on the USGS National Map Accuracy Standards. This margin is represented on the map to account for the necessary limitations of large-scale mapping when applied to site-specific coordinates.

There may be significant errors in the map presented and should be verified by the applicant before submission to ADEQ or delegated agency. Other data sources or field data may be necessary to demonstrate the location complies with R18-9-A311(B). Best available data should be used in site evaluations. Direct field observation and site-specific sampling shall override these map classifications; where on-site physical evidence contradicts the digital map unit, the in-situ field data constitutes the "Best Available Data" for regulatory submission. Neither the information presented, nor the map itself, are official documents.

R-18-9-A311(B)(1)(2) - A person may install a seepage pit only in valley-fill sediments in a basin-and-range alluvial basin and only if the seepage pit performance test results meet the criteria specified in R18-9-A312(E). The person shall specify in the Notice of Intent to Discharge that no limiting conditions described in R18-9A310(C) and (D) were identified at the site.