Section 110. Preliminary engineering proposal

A. Objective. The objective is to facilitate a determination by the department that the proposed design selected by the owner either requires, or does not require, submission of design documents for a formal technical evaluation to establish that the following standards will be reliably met by operation of the facility or system: (i) compliance with effluent limitations and treatment requirements established by the board; and (ii) conformance with applicable minimum requirements established by this chapter and standards contained in this chapter, in order that a CTC be issued.

B. Content. The preliminary engineering proposal when submitted for evaluation shall consist of an engineering report and preliminary plans which shall contain the necessary data to portray the sewerage system or treatment works problems and solutions. The requirement for a complete preliminary engineering proposal for small flow or minor projects (design flow less than one million gallons per day (mgd)) can be waived by the department in accordance with the letter from the owner's engineer summarizing the agreements reached at the preliminary engineering conference. For all proposals involving sewerage systems or treatment works, whether new or upgraded, the engineer shall make an evaluation of the l00-year flood elevation at the proposed site or sites, using available data and sound hydrologic principles. If a flood potential is indicated, the flood plain boundaries shall be delineated on a site map, showing its relation to the proposed facility or facilities and actions proposed to comply with this chapter shall be included in the preliminary engineering proposal or with the letter summarizing the agreements reached at the preliminary engineering conference. A conceptual plan for closure of the treatment works shall be discussed prior to final design to anticipate such an occurrence. On major projects (design flow of 1 mgd or more) excluding sewerage systems that are exempted from technical evaluation, the preliminary engineering proposal can include as a minimum the following information as applicable:

1. Mapping of present site location and evaluation of site constraints.

2. Data supporting predicted service population.

3. Identification of specific service area for immediate consideration and possible extensions.

4. Data, including reliable measurements or predictions of design flow and analyses of sewage constituents as a basis of process design.

5. Description of treatment process and flow plans identifying the proposed arrangement of basins, piping and related equipment with unit operation design parameters and sizes.

6. Description of sludge management method.

7. Plan for imposed operations requirements, i.e., certain unit operations may be required to operate independently of others in accordance with the reliability classification, while achieving the treatment performance necessary to meet permit limits under average design conditions.

8. Demonstration of compliance with state and local laws and regulations.

9. Summary of findings, conclusions and recommendations.

10. Description of existing institutional constraints or other unresolved problems that influence selection of alternative solutions.

11. Estimate of capital and operating costs of all alternatives presented if available as public information.

12. For those projects for which a Virginia Revolving Loan will be requested, the ways in which the special requirements contained in Title II of P.L. 92-500 will be met (infiltration, cost effectiveness, etc.).

13. Staffing and operating requirements for facility.

14. Identification consistent with all applicable area wide plans, of drainage basin, service area, and metropolitan area plans.

15. Designation of owner's representative for design purposes.

16. For land application proposals, the information required by Part III (9VAC25-790-310 et seq.) of this chapter, as appropriate.

The format for the Preliminary Engineering Proposal is listed in Part IV (9VAC25-790-940 et seq.) of this chapter.

C. Approval. The department will approve or disapprove the preliminary engineering proposal and notify the owner in accordance with 9VAC25-790-80 C.

Historical Notes

Former 12VAC5-581-160 derived from Volume 18, Issue 10, eff. February 27, 2002; amended and adopted as 9VAC25-790-110, Virginia Register Volume 20, Issue 09, eff. February 12, 2004.

Statutory Authority

§ 62.1-44.19 of the Code of Virginia.