This document details guidance for assessing buoyancy control needs for Infiltrator Water Technologies (Infiltrator) IM-Series tanks. The information presented is intended to assist in determining if buoyancy control measures are required during installation, based on site-specific conditions and applicable regulations. It is crucial to consult local health departments or permitting authorities for specific requirements, as these may supersede the guidelines provided. This guidance applies to Infiltrator tank models IM-540, IM-1060, and IM-1530.
Assessing Buoyancy Control Needs
The need for buoyancy control is determined by evaluating the water height outside the tank relative to the outlet pipe saddle height and the depth of soil cover above the tank. The process involves a two-step assessment, utilizing Table 1 and Figures 1 and 2 as outlined in the provided documentation.
Step 1 involves verifying that the water level outside the tank is below the outlet pipe saddle height. If this condition is not met, buoyancy control measures are required. Step 2 then utilizes Table 2 (not fully provided in the source material) to determine the minimum requirements for buoyancy control. The documentation emphasizes that IM-Series tanks should not be installed in locations where the water level outside the tank exceeds the height of the outlet pipe saddle.
Parameters for Buoyancy Control Determination
Two primary parameters are used to assess buoyancy control requirements: water height above the tank bottom (Parameter I) and the depth of soil cover above the tank top (Parameter II). Water height corresponds to the seasonal high groundwater elevation or perched water elevation, measured from the bottom of the tank. A minimum of 6 inches (150 mm) of soil cover backfill is required.
Table 1 categorizes water height into four ranges:
- Greater than 43 inches (1,075 mm)
- Between 36 inches (900 mm) and 43 inches (1,075 mm)
- Between 30 inches (750 mm) and 36 inches (900 mm)
- Less than 30 inches (750 mm)
The depth of soil cover above the tank top is then cross-referenced with these water height ranges to determine if buoyancy control is necessary for specific tank models.
Utilizing Table 1 for Buoyancy Control Assessment
Table 1 provides a matrix for determining buoyancy control requirements based on the two parameters described above. Users are instructed to locate the row in Table 1 corresponding to the water height outside the tank and follow that row to the right until reaching the column corresponding to the depth of soil cover proposed above the tank top. If the specific tank model (IM-540, IM-1060, or IM-1530) is listed in that cell, buoyancy control is required. If the tank model is not listed, no buoyancy control is required.
Figure 1 illustrates the assessment of water elevation, while Figure 2 provides a visual representation of the buoyancy control parameters used in Table 1. These figures are intended to aid in understanding the relationship between water height, soil cover, and the need for buoyancy control.
Importance of Regulatory Compliance
The documentation explicitly states that tank buoyancy control measures must be implemented according to state and/or local regulations. These regulations may supersede the guidelines provided by Infiltrator. Therefore, it is essential to consult with the local health department or permitting authority to ensure compliance with all applicable requirements. The documentation advises contacting these authorities if there is any uncertainty regarding the specific requirements for a particular site.
Contacting Technical Services
For assistance with buoyancy control assessment or any other technical questions related to Infiltrator IM-Series tanks, users are directed to contact Infiltrator Water Technologies' Technical Services Department at 1-800-221-4436. This resource is available to provide guidance and support in ensuring proper installation and operation of the tanks.
Additional Installation Considerations
While the primary focus of this document is buoyancy control, it references the Infiltrator IM-Series Tank Installation Instructions and Riser Connection Guidance documents for completing the installation process when buoyancy control measures are implemented. These additional resources provide detailed instructions on the proper installation techniques and procedures.
Conclusion
The provided documentation outlines a method for assessing buoyancy control needs for Infiltrator IM-Series tanks. The assessment process involves evaluating water height and soil cover, utilizing Table 1 and associated figures to determine if buoyancy control measures are required. Compliance with state and local regulations is paramount, and consultation with local authorities is recommended. Proper implementation of buoyancy control measures, when necessary, ensures the long-term stability and performance of the installed tanks.