GOALWhere potentially hazardous conditions exist, hazardous events are more apt to occur. As an example, unstable slopes can become a landslide area when triggered by severe or continuing rains, by poorly selected sites and poorly designed land disturbance. Colorado law requires counties and municipalities to control land development in areas where existing hazards have been identified.
The intent of the policies in this section is to identify hazards in the North Mountains area which should be mitigated or eliminated prior to development and to identify the governmental entities with the authority to safeguard people, property and the environment from injury or damage caused by hazardous conditions and events which are natural or triggered by human activities.
GOALProtect life and property from the adverse impacts of natural and man-made hazards.
1. Ensure that land use activities do not aggravate geologic hazards, and ensure that grading and excavation do not accelerate erosion.
2. Ensure that land use activities do not increase the risk of wildfire.
3. Ensure that air and water intended for human consumption meet the applicable federal and state air and water quality standards for radioactivity.
4. Limit the type of land uses permitted in areas where potential hazards due to radioactivity exist.
5. Protect the public within 10 miles of the Rocky Flats Nuclear Facility in the event of a release of hazardous material.
6. Protect the public from health hazards caused by electromagnetic radiation from telecommunication towers, power lines, etc.
7. Protect people and property from increased risk of flooding.
8. Ensure that land use on or adjacent to abandoned sanitary landfills has adequate protection from methane gas and differential settlement.
9. Ensure that the spread of noxious weeds is not enhanced by improper grading and development practices.
10. Fit development to terrain to ensure that development does not increase the potential for adverse impacts in geohazard areas.
11. Ensure nitrate contamination will not be a hazard to present and future residents. See the Water & Sanitation section for additional information.
In addition to the following policies, the criteria in the Mountain Site Design Criteria section which apply to hazards should be followed.
Red text identifies policies which can be applied in the land use review processes.
Various combinations of geologic hazard conditions are found throughout the study area. These include Slope Failure Complex, Unstable Slopes, rockfalls, landslides and subsidence.
1. No development should be allowed in zoned geologic hazard areas unless adequate mitigation or elimination of the potential hazard can be demonstrated. Hazard areas in the North Mountains area are on the Geologic Hazards Overlay Zone District, which are shown on the Environmental Constraints map at the back of the Plan.
Geologic hazards are described in the Appendix.
2. In unzoned hazard areas, each site should be reviewed and the appropriate site development criteria should be applied from the Mountain Site Design Criteria section.
3. Development activities should be designed to ensure adequate slope stability, and should result in a natural appearance which blends in with the surrounding landscape.
4. Drainage on unstable slopes should be designed to improve slope stability.
5. Final land forms which result from development activities should be stable and revegetated with drought resistant species to control erosion and improve stability.
6. Existing structures in the area around a proposed project should be protected from adverse impacts caused by the project. Existing potential hazards should not be aggravated by development activity. These adverse impacts include, but are not limited to:
a. disturbance of existing vegetation, which can lead to accelerated erosion and sedimentation;
b. aggravation or acceleration of existing potential hazards.
7. Abandoned mines should be fenced, posted and mapped. Mine openings should be closed.
Highly erodible soils are easily disturbed soils, having certain characteristics which have been identified by the Soil Conservation Service. Accelerated erosion can cause the destruction of aquatic life, increase the risk of flooding and increase pollution.
1. Overgrazing caused by livestock should be avoided by limiting the number of livestock, or limiting the area set aside for livestock. This is especially important on small lots where well and septic are used.
2. Disturbed areas should be stabilized as quickly as possible to reduce fugitive dust and erosion potential.
C. Wildfire HazardsThe threat of wildfire is a constant hazard faced by mountain area residents. As development and related human activity continues to increase in the North Mountains area, the risk of wildfire will increase. Therefore, it will be important to reduce the risk of wildfire through mitigation, maintenance, education, and by providing adequate access for fire protection equipment and water supplies.
The dead wood which is accumulating at an increasing rate on public and private land heightens the potential for wildfires which cross county boundaries. Intergovernmental cooperation will be needed to cope with this problem.
Key to wildfire management are several forest fuel types which warrant special attention.
These fuel types may present serious problems for fire protection on any slope. Often, it is not possible for fire fighters and their equipment to protect property and lives where these fuel types are present. Such fuels include, but are not limited to: Scrub Oak, Lodgepole Pine, and Ponderosa Pine.
1. Accepted methods of forest land management should be used to reduce all severe wildfire hazard areas to a low or moderate rating.
2. Jefferson County and the State Forest Service should use the same standards for the measurement of wildfire hazards.
3. Jefferson, Clear Creek, Gilpin, and Boulder Counties should work with the Colorado Forest Service to develop and implement a program to reduce the hazard of wildfire. This program should include:
a. a hazard overlay map showing the degree of wildfire hazard, i.e., severe, moderate and low;
b. a standard procedure to ensure the completion and long-term maintenance of fuel hazard mitigation for all new development;
c. a procedure to ensure the completion and the long-term maintenance of fuel hazard mitigation for existing development;
d. a description of fuel hazard mitigation practices, e.g., forest thinning, fuelbreaks to protect structures and access, fire retardant building materials, onsite water supplies, and access requirements for fire protection equipment, etc.;
e. an educational program for public and private landowners, residents, and business people, in the four counties, to inform them about wildfire hazards and mitigation techniques;
f. an active, environmentally safe pest management program to be used on public and private land;
g. a designated management structure to oversee program implementation;
h. an implementation schedule; and
i. a funding mechanism to pay for the program.
4. When the program described in Policy 3 above has been developed, Jefferson County should take appropriate action to adopt the resolutions, regulations and work programs necessary to implement the recommendations of the program.
5. Until the program in Policy 3 above has been developed, Jefferson County should create and adopt a wildfire hazard overlay map. It should be used as an indicator of the presence or absence of wildfire hazard areas with the degree of wildfire severity shown. The provisions of Section 44: W-H of the County Zoning Resolution should be followed. Jefferson County should implement the recommendations in 3.a-i. above, to the extent possible.
6. Development proposals in areas where severe or moderate wildfire hazards are present should continue to be referred to the Colorado State Forest Service and local fire protection districts to assess the severity of the wildfire hazard, determine the mitigation techniques which will be needed and the fire protection measures required. Colorado State Forest Service Wildfire Hazard maps and Jefferson County Wildfire Hazard and Fireline Intensity maps should be used to determine hazard levels, which should be confirmed by site inspections.
General fire protection policies are in the Public Facilities, Services & Utilities section of this Plan and additional wildfire hazard information is included in the Appendix.
7. To achieve excellent site design and the maximum number of units allowed under the Housing policies, structures should not be located in high wildfire hazard areas, e.g., fire chimneys.
8. Local fire departments should apply consistent and reasonable standards in issuing permits for prescribed burning of slash, which is a wildfire hazard. These standards should apply to all applications, whether they are public agencies or private individuals.
See the Public Facilities, Services & Utilities section of this Plan for additional fire protection policies.
D. Radiation HazardsRadioactive elements are natural components of the mineral rich rocks of the Front Range. Radon-222, an inert, radioactive gas, is a radioactive decay product of Radium-226 (member of the Uranium-238 decay chain). Radon-222 and Radium-226 are the important radioactive elements from a health standpoint.
1. Radon
Radon is emitted from the earth and can accumulate inside buildings where it can become a health hazard. Preventive and corrective measures can be used to avoid and mitigate the hazard. Standards for safety have been set by the U.S. Environmental Protection Agency which are higher than the standards advocated by the American Society of Heating, Refrigerating and Air Conditioning Engineers. It is less expensive and more efficient to construct a home using simple radon mitigation methods than trying to retrofit an existing structure once high levels of radon are discovered.
a. The Jefferson County Building Code should require that new construction, in areas which have high levels of natural radioactivity, use building techniques to prevent high radon levels.
b. Jefferson County should adopt regulations which would ensure that construction techniques are used which would reduce high levels of radon. These regulations could be incorporated into the Land Development Regulation, and/or be placed as a note or restriction on plats and exemptions from platting which would require construction plans showing radon reduction techniques prior to issuing a building permit.
c. The Jefferson County Health and Planning Departments should work with the Colorado Health Department to set health safety standards for radon.
d. Jefferson County should initiate state legislation to require testing of air for radon prior to the resale of property and provide appropriate remedies to protect purchasers.
2. Drinking Water
There is concern about health-endangering amounts of nitrates and radiation in groundwater. Radiation results from natural radioactive deposits and other sources, e.g., mine dumps.
Some private wells in the area have been identified as having elevated levels of gross alpha radioactivity, i.e., uranium Radium-226. However, only a small fraction of existing wells have been tested by their owners, so the extent of the problem is unknown. Although removal processes are available for these constituents, careful design is required to avoid additional radiation problems. Large scale treatment facilities could engender radiation and waste disposal problems. Currently, there is not a state requirement for testing. The Colorado Geological Survey can be consulted for risk areas before new wells are drilled, and the U.S. Geological Survey's hydrogeological study, when completed, may be a source of information about geological and water relationships which have radiation hazard potential.
a. Jefferson County should initiate state legislation to establish state standards for radioactive elements in water. A well testing program should be created which requires water testing for radioactivity, as well as nitrates, prior to the sale of property, with or without structures in place.
b. Water used for human consumption should not exceed the maximum levels for radioactive elements as set forth by the Environmental Protection Agency (EPA).
3. Uranium Deposits
Uranium deposits occur in the North Mountains area. Uranium mines have been mapped and are not considered suitable for construction purposes by the Colorado Health Department. See the Appendix for additional information.
a. The Jefferson County Planning Department should refer to the State of Colorado and Jefferson County Health Departments' development proposals to evaluate the existence and extent of radioactivity which could impact proposed and existing development.
b. Uranium mines should not be built upon, nor should mining residue be used for construction purposes.
4. Rocky Flats Nuclear Facilities
Radioactive and hazardous materials such as plutonium, a radioactive isotope, is used at the Rocky Flats Nuclear Weapons Plant. If contained and controlled properly, there is minimal risk of exposure. The major concern is with the release of radioactive and hazardous material which could have adverse health impacts.
This type of release creates a planning dilemma more serious than a natural hazard such as flooding, because the type, particle size, and quantity of materials in a release cannot be reasonably anticipated with accuracy. In addition, wind speed and direction at the time of the release influences the size and shape of the affected area.
Areas within 10 miles from the plant are significant in the event of a release of radioactive isotopes into the environment.
Protecting people from probable exposure risks from industrial radioactive and hazardous materials in the event of a release is a major concern and should be considered when land use decisions are made.
a. The emergency response plan for notification and evacuation within 10 miles of the Rocky Flats facility should be communicated to residents within this area.
5. Electromagnetic Radiation
There is an increased awareness that health problems may be caused by the emission of electromagnetic radiation from transmission power lines, electrical substations, telecommunications facilities such as radio and television antennae and microwave installations. Studies of this problem are underway which could produce more definitive information on the health hazard potential from electromagnetic radiation. Another health concern focuses on the cumulative and interactive effect of the various types of radiation. As research provides more data on this subject, the Colorado and Jefferson County Health Departments should monitor the data, reevaluate the current standards and consider revising the current standards in accord with new findings.
a. The Jefferson County Health and Planning Departments should initiate a study to evaluate the potential health hazards associated with the emission of electromagnetic energy from power lines, communications facilities, substations, etc. This study should:
1) collect data and policies from other jurisdictions, health and regulatory agencies, scientific studies, industry reports;
2) provide for ongoing research into the problem, i.e., the cumulative effect of different sources of radiation;
3) evaluate the adequacy of the American National Standards Institute (ANSI) standard, which does not cover transmission lines, currently used to determine whether or not a different standard should be adopted;
4) identify hazard areas, i.e., safe distances from electromagnetic energy sources;
5) map facilities, including power lines, which emit electromagnetic energy;
6) adopt appropriate regulations, zoning resolutions and building codes for new development;
7) provide for corrective actions for existing developments which are at risk; and
8) assign responsibility for monitoring emission sources.
b. Development proposals in the vicinity of electromagnetic energy emission sources should be referred to the Jefferson County Health Department for evaluation of health hazards.
Construction in or any alteration to a floodplain can cause a potential danger to life, property, and the environment. The Jefferson County Floodplain Overlay District regulates development in the floodplains.
1. All development involving property where the 100-year floodplain exists should comply with the Jefferson County Floodplain Overlay Zone District.
2. The Jefferson County Drainage Engineer and the Planning Department should cooperate in drafting an amendment to the County Storm Drainage Design and Technical Criteria Manual to allow mitigation of a flood hazard in the mountains with a natural design approach.
3. Small impoundments under 10 feet, not regulated for safety by the State Division of Water Resources, should be examined by the County and/or the State to determine if a potential flood hazard exists.
4. When existing uses in the floodplain create or increase the flood hazard, a community floodplain mitigation and alternatives study should be done to find reasonable ways to reduce the hazard area. The following issues should be addressed in the study.
a. Human safety.
b. Design options, e.g., channelizations, which mimic the natural environment and configuration, etc.
c. Land use options, e.g., trails, open space.
d. Financial options, public and private.
e. Property value.
f. Community and County responsibilities.
The generation, transportation and disposal of toxic and hazardous wastes is a serious concern. However, the extent and nature of such activities in the North Mountains area is currently unknown.
1. All toxic and hazardous wastes should be transported to federal, state, and/or municipal approved disposal sites.
2. The handling, storage and transportation by truck and rail of all toxic and hazardous, and potentially hazardous materials and wastes, and explosives should comply with county, state, and federal laws and regulations, including the aggressive toxic waste minimization program as required by law.
3. Railroads and trucking companies should provide local fire districts and/or emergency handling teams with a list of the hazardous materials being transported through their districts, and provide copies of their emergency response plan.
4. Fire districts should be informed of chemicals, explosives, hazardous materials, products and their wastes stored or manufactured on sites, or transported within their districts.
5. The use or creation of toxic substances by industry should comply with county, state, and federal laws and regulations.
6. Additional waste transfer or recycling stations should be located in the North Mountains area when the demand for them exists. One criterion for location should be close access to major arterials or freeways.
7. Fire districts should review development referrals to assess their capacity to respond to fires and emergencies when hazardous materials are involved in a proposed project.
8. The Jefferson County Building Department should be encouraged to coordinate with the fire district of jurisdiction when construction plans are submitted for projects which will have hazardous materials onsite during construction and/or operation.
9. The Jefferson County Health Department should initiate, in cooperation with the Colorado Health Department, a study to establish and adopt health safety standards for the disposal of biomedical waste.
This flammable gas is produced by decaying organic matter which can build up inside structures and create the potential for an explosion. The extent of methane gas generated by abandoned landfills in the study area is not currently known.
1. Development proposed on or in the vicinity of abandoned sanitary landfills should comply with the following recommendations.
a. All structures on landfills should be properly vented to prevent methane build-up and be equipped with methane monitors and alarm systems.
b. Methane from landfills should be vented or collected prior to development.
c. The design of structures and improvements should be based on careful site design and subsurface testing before construction is permitted on landfills to prevent damage from differential settlement.
1. The County should revise its weed ordinance to comply with the Colorado Weed Management Act. Control techniques which should be considered are: environmentally sensitive early mowing and grazing. Jefferson County should add Canada Thistle and Musk Thistle to the noxious weed list. See Appendix for additional information.
1. Prairie dog populations should be controlled by landowners, including public entities, to prevent the spread of disease, increased erosion, damage to grasses propagated under the Federal Crop Recovery Programs, and danger to livestock from stepping into burrows.
1. In high wind areas, structures should be sited to avoid adverse impacts from blowing snow on adjacent roads and building entrances.
2. The amount of overlot grading that occurs at any one time should be limited to avoid dust pollution.
Impacts associated with helicopters and ultralights which land on private property are not always covered by existing federal laws and regulations. To ensure that these impacts are considered, Jefferson County should amend the Zoning Resolution to protect people from adverse impacts related to aircraft operation on privately owned land.
1. Proposed airport/heliport/ultralight locations should be reviewed on a site-by-site basis to ensure that noise, lighting, and other undesirable impacts on the surrounding areas are avoided.
2. Proposed sites should meet requirements of the appropriate regulatory agencies.
3. The County Zoning Resolution pertaining to aircraft should be amended to provide for control over the private use of light aircraft, helicopters and ultralights, when F.A.A. does not regulate them, to protect the safety and health of the public when landing sites are located.
4. Noise levels from aircraft should be within the acceptable decibel range set by the State of Colorado and/or Jefferson County. The stricter standard should apply.
5. Landing approach and takeoff patterns should not endanger people or property.