Chapter 17.12 STANDARDS FOR PREPARING CRITICAL AREAS REPORTS AND MITIGATION PLANS

Chapter 17.12
STANDARDS FOR PREPARING CRITICAL AREAS REPORTS AND MITIGATION PLANS

Sections:

17.12.005 Information – Use.

17.12.010 Critical areas reports.

17.12.020 Critical areas reports – Wetlands and wetland mitigation plans.

17.12.030 Critical areas reports – Species and habitats and habitat management plans.

17.12.040 Geotechnical reconnaissance reports and geotechnical investigation reports.

17.12.050 Erosion hazard assessments.

17.12.060 Aquifer impact assessments and hydrogeologic site evaluations.

Prior legislation: Ords. 2821 and 3082.

17.12.005 Information – Use.

The following information shall be used during the preparation of critical areas reports and mitigation plans by qualified experts. (Ord. 3352 § 1, 2017).

17.12.010 Critical areas reports.

(1) The applicant shall be required to submit reports as appropriate for the applicable critical areas found in the critical areas determination. The report shall be prepared in accordance with the minimum requirements listed below and within the additional requirements listed for each applicable critical area found in this chapter. Critical areas reports for two or more types of critical areas shall meet the report requirements for each relevant type of critical area.

(2) The critical areas report and site map shall include:

(a) North arrow;

(b) Property line dimensions;

(c) Location and dimensions of all existing and proposed development or alterations, including public and private roads, sewer and water lines, wells, utilities, easements, water sources, lakes and springs, drainage facilities, on-site sewage disposal, and drain field areas, within the property boundary;

(d) Location information of property (legal description, parcel number, physical address);

(e) The names and contact information of the applicant and the persons preparing the report and conducting any field investigation;

(f) The date of any field investigation;

(g) An assessment of the probable impacts to critical areas resulting from the development of the site and the proposed development; and

(h) A discussion of the development standards applicable to the critical areas and proposed activity.

A mitigation plan, if needed, to offset any impact will be prepared in accordance with mitigation plan requirements of each applicable critical area found in this chapter. (Ord. 3352 § 1, 2017).

17.12.020 Critical areas reports – Wetlands and wetland mitigation plans.

(1) Critical Areas Reports: Wetlands. In addition to the general critical areas reports requirement of LMC 17.12.010, a critical areas report for wetlands shall meet the requirements of this section.

A wetland determination report is a limited study and determines the presence or absence of wetlands. A wetland determination is used to provide an environmental analysis to justify that wetlands are not present within the project area.

A wetland delineation report is a more detailed study and is prepared when a project area does contain critical areas. A wetland delineation report shows the boundary of the wetland as determined in the field and provides detailed analysis of environmental conditions and regulatory requirements.

(a) Preparation by a Qualified Expert. A critical areas report for wetlands and an on-site wetland determination or wetland delineation report shall be prepared by a qualified expert for wetlands meeting the requirements in LMC 17.10.050, Definitions.

(b) Critical Areas Reports: Wetlands. A critical areas report for wetlands shall contain a written assessment and accompanying maps of the wetlands and their buffers within and adjacent to the project area. The following information shall be provided at a minimum:

(i) Site characteristics including topography, total acreage of the property, and maps showing delineated wetlands and other water bodies within the study area in accordance with the approved federal wetland delineation manual and applicable regional supplement;

(ii) Assessment of existing conditions of wetlands and wetland buffers including wetland acreage (or square footage), water regime, vegetation, soils, landscape position, surrounding land uses, and functions;

(iii) Description of Cowardin classifications of vegetation communities, hydrogeomorphic classification, and estimated distances to and area of other off-site wetlands and water bodies within the vicinity of the subject wetland;

(iv) Identification of the wetland’s category as defined in this chapter, including the wetland category using the Washington State Wetland Rating System for Western Washington: 2014 Update (Ecology Publication No. 14-06-029 or as revised and approved by Ecology), and appropriate wetland rating forms with associated maps;

(v) A wetland buffer recommendation and rationale for the buffer size based on Tables 17.10.110-1, 17.10.110-2, or 17.10.110-3;

(vi) Completed wetland determination data forms from the U.S. Army Corps of Engineers’ Regional Supplement for the Western Mountains, Valleys, and Coast Region: Version 2 (2010), or as revised, numbered to correspond to each sample point;

(vii) The following maps, at a minimum:

(A) USGS quadrangle map drawn to scale and including a north arrow, public roads and other known landmarks in the vicinity with the site boundaries clearly defined.

(B) A Natural Resource Conservation Service soil map identifying the soil types and the site boundaries.

(D) Site Map. This map shall be drawn to a useable scale, one inch equals 100 feet or better, and shall include a north arrow and all of the following requirements:

1. Site boundary, property lines and dimensions;

2. Wetland boundaries based upon a qualified expert’s delineation, and depicting wetland area, sample points, and Cowardin classes;

3. Recommended wetland buffers;

4. Internal property lines such as rights-of-way and easements;

5. Existing physical features of the site including, but not limited to, buildings and other structures, fences, roads, utilities, parking lots, water bodies; and

6. Topographic elevations.

(viii) A mitigation plan, if required per subsection (2) of this section.

(2) Wetland Mitigation Plans. All critical areas mitigation projects required pursuant to this chapter either as a permit condition or as the result of an enforcement action shall follow a mitigation plan approved by the department prior to any site disturbance. Prior to any submittals of mitigation plans for critical areas alterations, the applicant shall demonstrate mitigation sequencing for any impacts, intentional or otherwise. Mitigation sequencing shall follow the standards described in LMC 17.10.110(7)(a).

The director may determine a peer review be conducted at the applicant’s expense. The director may seek assistance from resource agencies prior to making a decision on the completeness of their application.

(a) Preparation by a Qualified Expert. When a wetland mitigation plan is required, it shall be prepared by a qualified expert for wetlands meeting the requirements in LMC 17.10.050, Definitions.

(b) Critical Areas Reports: Wetlands. A critical areas report for wetlands shall accompany or be included in the mitigation plan and include the minimum parameters described in subsection (1) of this section.

(c) Wetland Mitigation Plans. Full guidance can be found in Wetland Mitigation in Washington State – Part 2: Developing Mitigation Plans (Version 1), Publication No. 06-06-011b, March 2006, or as revised. If a wetland mitigation bank is used to compensate for wetland impacts, then the most current Interagency Review Team guidance for preparing bank use plans should be followed. The wetland mitigation plan shall include a written report and plan sheets that contain, at a minimum, the following elements:

(i) The name and contact information of the applicant; the name, qualifications, and contact information for the primary author(s) of the mitigation plan.

(ii) Description of the proposal.

(iii) Summary of the impacts and proposed mitigation concept.

(iv) Identification of all local, state, and/or federal wetland-related permit(s) required for the project.

(v) Description of how the project design has been modified to avoid, minimize, or reduce adverse impacts to wetlands.

(vi) Description of the existing wetlands and buffers proposed to be altered. Include acreage (or square footage), water regime, vegetation, soils, landscape position, surrounding land uses, and functions.

(vii) Description of impacts in terms of acreage by Cowardin classification, hydrogeomorphic classification, and wetland rating, based on the Washington State Wetland Rating System for Western Washington: 2014 Update (Washington Department of Ecology Publication No. 14-06-029, or as revised and approved by Ecology).

(viii) Description of the mitigation site, including location and rationale for selection. Include an assessment of existing conditions: acreage (or square footage) of wetlands and uplands, water regime, sources of water, vegetation, soils, landscape position, surrounding land uses, and functions.

(ix) Surface and subsurface hydrologic conditions, including an analysis of existing and proposed hydrologic regimes for enhanced, created, or restored mitigation areas. Include illustrations of how data for existing hydrologic conditions were used to determine the estimates of future hydrologic conditions.

(x) A description of the proposed actions for compensation of wetland and upland areas affected by the project. Include overall goals of the proposed mitigation, including a description of the targeted functions, hydrogeomorphic classifications, and categories of wetlands.

(xi) A description of the proposed mitigation construction activities and timing of activities.

(xii) Performance standards (measureable standards for years post-installation) for upland and wetland communities, a monitoring schedule, and a maintenance schedule and actions proposed by year.

(xiii) A contingency plan and a schedule for its implementation shall be included in the event the stated objectives are not accomplished.

(xiv) A description that the monitoring reports shall be submitted to document the performance standards, successes, problems, and contingency actions of the mitigation project. The mitigation project shall be monitored by the applicant or a qualified expert for a period necessary to establish that the mitigation is successful, but not for a period of less than five years. Creation and forested wetland mitigation shall be monitored for a period of at least 10 years. Monitoring reports shall be submitted to the department in years one, three, five, seven and 10.

(xv) The mitigation area and any associated buffer shall be located in a critical areas tract or a conservation easement pursuant to LMC 17.10.090(9).

(xvi) The scaled plan sheets for the mitigation site shall contain, at a minimum:

(A) Boundaries of the existing wetland and buffers, proposed areas of wetland and/or buffer impacts, location of proposed wetland and/or buffer compensation actions.

(B) Existing topography in the zone of the proposed mitigation actions if any grading activity is proposed in the mitigation area(s). Include existing cross-sections of wetland areas on the development site that are proposed to be altered and for the proposed areas of wetland or buffer mitigation.

(C) Conditions expected from the proposed actions on site, including future hydrogeomorphic types, vegetation community types by dominant species (wetland and upland), and future water regimes.

(D) Required wetland buffers for existing wetlands and proposed mitigation areas.

(E) A planting plan for the mitigation area, including all species by proposed community type and water regime, size and type of plant material to be installed, spacing of plants, typical clustering patterns, total number of each species by community type, and timing of installation. (Ord. 3352 § 1, 2017).

17.12.030 Critical areas reports – Species and habitats and habitat management plans.

(1) Critical Areas Reports: Species and Habitat. In addition to the general critical areas report requirements of LMC 17.12.010, a critical areas report for fish and wildlife habitat conservation areas shall meet the requirements of this section. Technical justification shall be provided where any information is not deemed applicable by the qualified expert.

(a) Preparation by a Qualified Expert. A critical areas report for fish and wildlife habitat conservation areas and an on-site field investigation to evaluate the potential presence or absence of designated critical fish or wildlife species or habitat shall be prepared by a qualified expert for fish and wildlife habitat conservation areas meeting the requirements in LMC 17.10.050, Definitions.

(b) Critical Areas Reports: Species and Habitat. A fish and wildlife habitat conservation area report is a written report and accompanying maps, which shall contain, at a minimum, the following:

(i) Identification of any species of local importance, priority species, or state or federally designated endangered, threatened, sensitive, or candidate species that have a primary association with habitat on or adjacent to the project area, and assessment of potential project impacts to the use of the site by the species;

(ii) A discussion of any federal, state, or local special management recommendations, including Washington Department of Fish and Wildlife habitat management recommendations, that have been developed for species or habitats located on or adjacent to the project area;

(iii) A detailed discussion of the project and direct and indirect potential impacts on habitat by the project, including potential impacts to water quality; and

(iv) A detailed description of vegetation on and adjacent to the project area and its associated buffer and habitat provided to fish and wildlife; and

(c) Additional Information May Be Required. When appropriate due to the type of habitat or species present or the project area conditions, the city planner may also require the habitat conservation area report to include:

(i) An evaluation by an independent qualified expert regarding the applicant’s analysis and the effectiveness of any proposed mitigating measures or programs, to include any recommendations as appropriate; or

(ii) A request for consultation with the Washington Department of Fish and Wildlife or other appropriate agency or tribe.

(2) Habitat Management Plans. At a minimum, the habitat management plan shall typically contain the following information.

(a) Preparation by a Qualified Expert. A habitat management plan shall be prepared by a qualified expert for fish and wildlife habitat conservation areas meeting the requirements in LMC 17.10.050, Definitions.

(b) Critical Areas Reports: Species and Habitat. A critical areas report for fish and wildlife habitat conservation areas shall accompany or be included in the habitat management plan and include the minimum parameters described in LMC 17.12.010.

(c) Habitat Management Plans. The habitat management plan is a written report and plan sheets that shall contain, at a minimum, the following information:

(i) Name and contact information of the applicant; the name, qualifications, and contact information for the primary author(s) of the plan.

(ii) Description of the proposal.

(iii) Summary of the impacts and proposed habitat management plan concept.

(iv) Identification of all local, state, and/or federal permit(s) required for the project.

(v) A discussion of measures, including avoidance, minimization, and mitigation, proposed to preserve existing habitats and restore any habitat that was degraded prior to the current proposed land use activity.

(vi) An analysis of how the proposed development activities will affect fish and wildlife habitat conservation area and any critical species.

(vii) Provisions to reduce or eliminate the impact of the proposed development activities on any fish and wildlife habitat conservation area and critical species, and description of replacement of any lost habitat functions.

(viii) Prohibition or limitation of development activities within fish and wildlife habitat conservation area.

(ix) Establishment of buffers around fish and wildlife habitat conservation areas demonstrating rationale for buffers consistent with WAC 365-195-900 through 365-195-925.

(x) A detailed description of vegetation on and adjacent to the project area and its associated buffers and demonstration of how the applicant will retain vegetation or vegetation critically important to threatened and endangered species.

(xi) Establishment of monitoring and management practices that will protect habitat after the site has been developed, including proposed monitoring and maintenance programs.

(xii) The mitigation area and any associated buffer shall be located in a critical areas tract or a conservation easement pursuant to LMC 17.10.090(9).

(xiii) Habitat management plan map drawn to scale one inch equals 100 feet or recent land survey showing the following items:

(A) All lakes, ponds, streams, wetlands, or tidal waters on, or within 300 feet of, the subject property, including the name (if named), and ordinary high water mark of each, and stream type and wetland category consistent with WAC 222-16-030 and LMC 17.10.110(2);

(B) The location and description of the fish and wildlife habitat conservation area on the subject property, as well as any potential fish and wildlife conservation areas within 300 feet of the subject property as shown on maps identified in the Summary of Map Sources (Table 17.10.100) and/or housed within the department;

(xiv) Review and comments by the Washington Department of Fish and Wildlife, and other appropriate state and federal agencies that review SEPA environmental checklists.

(d) The director may determine a peer review be conducted by the applicant at the applicant’s expense. The director may seek assistance from resource agencies prior to making a decision on the completeness of the application. (Ord. 3352 § 1, 2017).

17.12.040 Geotechnical reconnaissance reports and geotechnical investigation reports.

(1) Geotechnical Reconnaissance Reports. A geotechnical reconnaissance is intended to be a limited study of geological hazards at a site, and does not include the collection of any subsurface soil, rock and groundwater data (i.e., no borings, test pits or cone penetration tests are performed). The scope of services shall include, at a minimum, a site visit and literature review performed by the qualified expert for geological hazards. A geotechnical reconnaissance is appropriate for erosion, volcanic and mine hazards, but will limit the ability of the qualified expert to evaluate landslide and seismic (primarily liquefaction) hazards. A geotechnical reconnaissance is not acceptable to evaluate landslide and seismic hazards, unless the qualified expert can provide compelling evidence as to why a geotechnical investigation is not required. After evaluating erosion, volcanic, and mine hazards with a geotechnical reconnaissance, it is possible that the qualified expert may recommend preparing a supplemental geotechnical investigation report as detailed in subsection (2) of this section.

(a) Preparation by a Qualified Expert. A geotechnical reconnaissance report shall be prepared by a qualified expert for geological hazards meeting the requirements in LMC 17.10.050, Definitions.

(b) Geotechnical Reconnaissance Reports. A geotechnical reconnaissance shall include at the minimum the following:

(i) A discussion of the surface and subsurface geologic conditions of the site.

(ii) A site plan of the area delineating all areas of the site subject to landslide geological hazards (i.e., erosion, sliding, earthquake, and other geological events) based on mapping and geotechnical evaluation. Additionally, all geological hazards within 200 lateral feet of the site and all landslide hazards off the property but anticipated to impact the proposed development should be indicated on the site plan.

(iii) A contour map of the proposed site, at a reasonable scale (not smaller than one inch equals 100 feet) that clearly delineates slopes for ranges between 15 and 29 percent and 30 percent and greater, and includes figures for area coverage of each slope category on the site.

(iv) Site Geology Information.

(A) Topographic data. Contour map of proposed site at a scale no greater than one inch equals 100 feet that clearly delineates the slopes 15 percent and greater, including figures for area coverage of each slope category on the site.

(B) Site history. Description of any prior grading, soil instability, or slope failure.

(v) Geotechnical Engineering Information.

(A) Slope stability studies and opinion of slope stability;

(B) Proposed angles of cut and fill slopes and site grading requirements;

(C) Structural foundation requirements and estimated total and differential foundation settlements, including dynamic settlement in areas determined to be susceptible to soil liquefaction;

(D) Soil compaction criteria;

(E) Proposed surface and subsurface drainage;

(F) Lateral earth pressures, including static passive and active earth pressures, as well as dynamic active earth pressures;

(G) Erosion vulnerability of site;

(H) Suitability for fill, including the use of on-site soils for use as fill;

(I) Laboratory data and soil index properties for soil samples; and

(J) Building limitations.

(vi) Site Evaluation. Evaluation of the ability of the site to accommodate the proposed activity. Where a valid geotechnical investigation report has been prepared within the last five years for a specific site, and where the proposed activity and surrounding site conditions are unchanged, said report may be used and a new report may not be required, at the discretion of the director or the city engineer, and provided the geotechnical report complies with the current building code.

(vii) The seal of the geotechnical engineer or engineering geologist.

(2) Geotechnical Investigation Reports. A geotechnical investigation report includes investigating subsurface soil, rock, and groundwater conditions to better assess the geological site hazards. The scope of services shall include, at a minimum, a site visit, a subsurface investigation (i.e., borings, test pits, or cone penetration tests) and literature review performed by the qualified expert for geological hazards. A geotechnical investigation shall be required to evaluate landslide and seismic hazards, unless the qualified expert can provide compelling evidence as to why a geotechnical reconnaissance is sufficient.

(a) Preparation by a Qualified Expert. A geotechnical investigation report shall be prepared by a qualified expert for geological hazards meeting the requirements in LMC 17.10.050, Definitions.

(b) Geotechnical Investigation Reports. The geotechnical investigation report shall include at a minimum the following:

(i) A discussion of the surface and subsurface geologic conditions of the site.

(iv) Site Geology Information.

(B) Subsurface data. Logs of borings, test pits and other exploratory methods, soil and rock stratigraphy, groundwater levels including seasonal changes, and laboratory test results.

(D) Seismic hazard. Data concerning the vulnerability of the site to seismic events.

(v) Geotechnical Engineering Information.

(A) Slope stability studies and opinion of slope stability based on a stated factor of safety for static and dynamic slope stability and a minimum horizontal ground acceleration as established by the current version of the building code (the minimum acceptable factor of safety for static slope stability shall be 1.5 and the minimum acceptable factor of safety for dynamic slope stability shall be 1.1);

(B) Proposed angles of cut and fill slopes and site grading requirements;

(C) Structural foundation requirements and estimated total and differential foundation settlements, including dynamic settlement in areas determined to be susceptible to soil liquefaction;

(D) Soil compaction criteria;

(E) Proposed surface and subsurface drainage;

(F) Lateral earth pressures, including static passive and active earth pressures, as well as dynamic active earth pressures;

(G) Erosion vulnerability of site;

(H) Suitability for fill, including the use of on-site soils for use as fill;

(I) Laboratory data and soil index properties for soil samples; and

(J) Building limitations.

(vii) The seal of the geotechnical engineer or engineering geologist. (Ord. 3352 § 1, 2017).

17.12.050 Erosion hazard assessments.

(1) Preparation by a Qualified Expert. An erosion hazard assessment shall be prepared by a qualified expert for geological hazards meeting the requirements in LMC 17.10.050, Definitions.

(2) Erosion Hazard Assessments. An erosion hazard assessment is a written report and plan sheets that contain, at the minimum, the following:

(a) An overview of existing channel characteristics and stream hydraulics at the subject property;

(b) An assessment of the probability for stream induced erosion to occur on the subject property and the estimated extent of the property that would be affected;

(c) A site map of the property, drawn to scale, delineating the relationship of the stream to the property, and existing erosion areas and/or potential erosion areas, and the proposed development, including structural dimensions;

(d) A cross-section map, drawn to scale and at two-foot contour intervals from the edge of the river’s surface to the furthest landward boundary of the property, and including the proposed development;

(e) The seal of the geotechnical engineer or engineering geologist. (Ord. 3352 § 1, 2017).

17.12.060 Aquifer impact assessments and hydrogeologic site evaluations.

(1) Aquifer Impact Assessments.

(a) Preparation by a Qualified Expert. An aquifer impact assessment shall be prepared by a qualified groundwater expert meeting the requirements in LMC 17.10.050, Definitions.

(b) Aquifer Impact Assessments. An aquifer impact assessment shall include, at a minimum, the following:

(i) Identification of the proposed land development activity including size, amount of impervious surface, vehicular usage and storage, and sources of water for consumption and other on-site usage.

(ii) Identification of geological, soil, topographic, and hydrologic features and conditions at the subject and abutting properties based on existing public information (e.g., soil surveys, topographic maps, Washington geology mapping, existing site well logs, etc.). These shall be displayed on a site map.

(iii) Identification of presumptive depth to groundwater.

(iv) Information on springs or wells within 500 feet of the site including information of water quality if readily available.

(v) Proposed plans for management of runoff including routing and infiltration if applicable. Infiltration of uncontaminated (e.g., roof) runoff is encouraged where feasible.

(vi) Provisions for a groundwater elevation and quality monitoring plan.

(vii) An evaluation of the proposed project impacts on groundwater quality and quantity for the CARA including a plan for the mitigation of any potential impacts on the CARA.

(2) Hydrogeologic Testing and Site Evaluations. If the director determines that hydrogeologic testing and site evaluation are required for development within a CARA, these investigations shall be conducted by a qualified groundwater expert meeting the requirements of LMC 17.10.050, Definitions, and approved by the city engineer, and shall typically include at least the following, listed below. Applicants are encouraged to use existing studies and resources within the same locality to the fullest extent possible such as: U.S. Soil Conservation Service data and USGS data, when available, and select qualified experts with localized knowledge of the Longview area.

(a) Preparation by a Qualified Expert. The hydrogeologic testing and site evaluation shall be conducted and a written report prepared by a qualified groundwater expert meeting the requirements in LMC 17.10.050, Definitions.

(b) Hydrogeologic Site Evaluation. Hydrogeologic site evaluations shall include, at a minimum, the following:

(i) Recommendations on appropriate mitigation, if any, to assure that there shall be no significant degradation of groundwater quality or quantity.

(ii) In addition, the testing and evaluation shall include, but not be limited to, an analysis of:

(A) Geologic setting and soils information of site and surrounding area;

(B) Water quality data, including pH, temperature, conductivity, nitrates, and bacteria;

(D) Recharge potential of facility site (permeability/transmissivity);

(E) Local groundwater flow, direction, and gradient;

(F) Surface water locations within 1,000 feet of the site;

(G) Data currently available on wells and springs within 1,300 feet of the project area; and

(H) Proposed best management practices. (Ord. 3352 § 1, 2017).