Criteria for Inspection

(1) The intent of 310 CMR 15.302 is to provide reasonable guidance for the inspection of existing systems in as non-intrusive a manner as possible, set forth the requirements for conducting an inspection, and to avoid damage to the system and any unnecessary disturbance of the surrounding soil area which is related to the treatment process. At a minimum, the septic tank and distribution box, if present, or cesspool, if present, shall be located, uncovered and inspected, and reasonable professional efforts shall be made to locate and identify other components and features, as described in 310 CMR 15.302(2) and (3). The inspection is not designed to provide information to demonstrate that the system will adequately serve the use to be placed upon it by the new owner. The inspection criteria are intended to allow for timely inspection to avoid undue delay in the transfer of property. (2) An inspection shall consist of the collection and recording of the following information: (a) a general description of the system components and layout; (b) quantification of the source/type of sanitary sewage. This should include type of use (domestic or commercial/industrial) as well as the design flow and whether or not the facility being served is occupied at the time of the inspection; (c) an analysis of the factors set forth in 310 CMR 15.303 (failure criteria) and, if the system has a design flow of 10,000 gpd or greater, 15.304 (threats to public health and environment); (d) water use records for the previous two years for facilities served by public water supply, if available from the supplier; (e) a description of the septic tank including: 1. approximate age, size, and condition of the tank; 2. distance between bottom of grease/scum layer and the bottom of the outlet baffle; 3. distance between the top of the scum layer and the top of the outlet tee; 4. thickness of the grease/scum layer; 5. depth of the sludge layer and distance from sludge to outlet tee; 6. physical condition of inlet and outlet tees; 7. any evidence of leakage into or out of tank; and 8. any evidence of backup of effluent. 9. a characterization of the distribution box, and of dosing tanks with pumps, if any, including: a. any evidence of solids carryover; b. leakage into or out of the distribution box; c. whether the flow is equally divided; and d. any evidence of backup. 10. a description of the condition of the soil absorption system including: a. any signs of hydraulic failure; b. condition of surface vegetation; c. level of ponding within disposal area; d. encroachments into disposal area; and e. other sources of hydraulic loading. 11. the location of private water supply well (if any) in relation to system components; and 12. a copy of pump-out records on file with the local Approving Authority. (3) The inspector shall make reasonable professional efforts to determine the location and condition of all system components and relevant physical features. If any component cannot be located or inspected, or any determination cannot be made, the inspector shall state on the inspection form the reasons and the steps taken to complete the inspection. At a minimum, reasonable professional efforts require compliance with the inspection requirements and protocol in 310 CMR 15.302(4) and (5). Where an inspection is conducted for the purpose of refuting or corroborating the findings of a prior inspection, reasonable professional efforts shall require, at a minimum, that the inspector employ methods to determine the location and condition of all system components and relevant physical features that are comparable to the methods employed by the prior inspector. Provided that these requirements are met, and the Approving Authority agrees with the findings in writing, the reinspection shall supersede the prior inspection unless otherwise determined in writing by the Approving Authority. (4) Determination of High Groundwater Elevation. A deep hole observation test is not required to determine high groundwater elevation during an inspection. High groundwater elevation shall be estimated by the inspector, using best professional judgment, based on the methods described in 310 CMR 15.302(4)(a) through (c). (a) The inspector shall review local maps and records of groundwater elevation (previous deep hole observation tests or groundwater monitoring results) on the site and nearby properties, if available. (b) If the system includes a cesspool, the cesspool shall be pumped during the inspection and then examined to determine whether groundwater flows into the cesspool, indicating that the cesspool is below high groundwater elevation. (c) If the system includes a septic tank and distribution box, the condition of these components and the surrounding soil shall be observed for indications that groundwater has infiltrated the system. Care should be taken not to destabilize the distribution box or the piping to or from the box. These minimum requirements shall not prevent the use of additional methods. The elevation of nearby water bodies, or evidence of groundwater infiltration in other subsurface structures (for example, cellars), or hand augering to determine depth may aid in determining whether the system is located in the groundwater. The methods used to determine high groundwater elevation shall be described in the inspection report. A system owner may choose to have the high groundwater elevation determined by an observation well or deep hole observation test to confirm or disprove the results obtained by the minimum requirements of 310 CMR 15.302(4), or in place of the minimum requirements. (5) Location of Soil Absorption System. The location of any cesspool must be determined. For systems with a septic tank and distribution box, excavation is not required to determine the location of the soil absorption system. Reference may be made to as-built plans of the system (if any). All components of the soil absorption system shall be located where the failure criteria specified in 310 CMR 15.303(1) are triggered. Where the failure criteria specified in 310 CMR 15.303(1) are not triggered, the location may be approximated by considering design flow, location of the distribution box and direction of outlet pipes, and physical condition of the site. The location may also be determined by running a metal snake or similar device from the outlet of the distribution box and using a metal detector, or use of similar methods. Nothing in 310 CMR 15.302(5) shall prevent an owner from choosing to establish the location of the leaching system through more intrusive methods. (6) Compliance with Department Guidance. The inspector shall complete the system inspection in accordance with the Department’s Guidance for the Inspection of Subsurface Disposal Systems.