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HomeMy WebLinkAboutP_Drainage_Plan_King_County_Appendix_C_180720_v3 APPENDIX “C” OPERATION AND MAINTENANCE MANUAL LARSON & ASSOCIATES, INC. SURVEYORS, ENGINEERS AND PLANNERS 9027 PACIFIC AVENUE, SUITE 4 TACOMA, WA 98444 (253) 474-3404 D08-053 B18000839 V3 REVISION Received: 07/20/2018 / aalexander BUILDING DIVISION APPROVEDBUILDING DIVISION THIS SET OF APPROVED PLANS MUST BE ON THE JOB AT ALLTIMES DURING CONSTRUCTION. THIS BUILDING IS NOT TO BEOCCUPIED UNTIL AFTER FINAL INSPECTION BY THE RENTONBUILDING DIVISION AND RECEIPT OF CERTIFICATE OFOCCUPANCY. APPROVAL SHALL NOT BE CONSTRUED AS THE AUTHORITY TOVIOLATE OR CANCEL ANY PROVISIONS OF CODES, ORDINANCES,OR OTHER REGULATIONS ENFORCED BY THIS CITY. DATE: 08/07/2018 RESPONSIBLE PARTY FOR THE MAINTENANCE OF THE PRIVATE STORM DRAINAGE SYSTEM UNTIL THE HOMEOWNERS ASSOCIATION BECOMES IN EFFECT: JK MONARCH P.O. BOX 188 PUYALLUP, WA 98371 CONTACT: RUSS SORKNESS PH: (253) 840-5660 ESTIMATED ANNUAL COST OF MAINTENANCE OF THE STORM DRAINAGE SYSTEM AS IDENTIFIED IN ATTACHMENT “A” IS $100 PER YEAR. NOTE: THIS OPERATION AND MAINTENANCE MANUAL SHALL BE KEPT AT THE PROJECT SITE AT ALL TIMES AND SHALL BE MADE AVAILABLE TO THE CITY OF RENTON FOR INSPECTION UPON REQUEST. Description of Chelan Creek Lot 2 Stormwater System. This proposal will include the construction of a single family residence and associated driveway. Per Appendix C of the King County Surface Water Design Manual, we will be applying Basic Dispersion Methods to this site per City of Renton Requirements and per the previously approved Plat. As mentioned above, the proposed driveway (approximately 506 SF) will be graded to direct runoff back to the plat road per the previously approved Chelan Creek Plat T.I.R. All roof runoff from the proposed house structure (approximately 1,973 SF) will be collected and conveyed via a 4” downspout tightline system to an existing storm stub located to the west of the proposed house. This stub will convey stormwater offsite to Tract “E” where it will enter a common dispersion trench for dispersal across the wetland buffer to the west. See attached Drainage Plan – Site Plan for additional information. ATTACHMENT “A” ATTACHMENT "A" MAINTENANCE PROGRAM Inspection Period: _____________________________________________ Number of Sheets Attached: _____________________________________ Date Inspected: _____________________________________________ Name of Inspector: _____________________________________________ Inspector's Signature: ____________________________________________ INSTRUCTIONS FOR USE OF MAINTENANCE CHECKLISTS The following pages contain maintenance needs for most of the components that are part of your drainage system, as well as for some components that you may not have. Let the City know if there are any components that are missing from these pages. Ignore the requirements that do not apply to your system. You should plan to complete a checklist for all system components on the following schedule: (1) Monthly from November through April (2) Once in late summer (preferable September) (3) After any major storm (use 1-inch in 24 hours as a guideline), items marked "S" only. Using photocopies of these pages, check off the problems you looked for each time you did an inspection. Add comments on problems found and actions taken. Keep these "checked" sheets in your files, as they will be used to write your annual report. Some items do not need to be looked at every time an inspection is done. Use the suggested frequency at the left of each item as a guideline for your inspection. ATTACHMENT “B” INSTRUCTIONS FOR THE OWNER/S IN Chelan Creek Lot 2 POLLUTION SOURCE CONTROLS The attached material includes information on pollution source controls. Pollution source controls are actions taken by a person or person representing a business to reduce the amount of pollution reaching surface and ground waters. Pollution source controls also called “best management practices” (BMP’s) include: Altering the activity (e.g., substitute not-toxic products or recycle) Enclosing or covering the activity. Segregating the activity (e.g. diverting surface water runoff away from an area that is contaminated.) Pollution source controls are needed because of the contamination found in surface water runoff from commercial areas and the effect of this contamination on aquatic life and human health. Research on urban runoff in the Puget Sound area and elsewhere has found oil and grease, nutrients, organic substances, toxic metals, bacteria, viruses, and sediments at unacceptable levels. Effects of contaminate runoff include closure of shellfish harvesting areas and swimming areas, pollution of wells, mortality of young fish and other aquatic organisms, tumors on fish, and impairment of fish reproduction. Chelan Creek Lot 2 project contains impervious surfaces that will collect contaminates from automobiles, garbage, and improperly disposed of chemicals. These materials are conveyed to the storm drainage systems and will enter into the ground water, if not treated properly. Attachment “B” contains a number of BMP’s for various uses within the development site. Each owner shall give a copy of the BMP’s suitable to this or her respective activity. If a certain activity is not contained in Attachment “B”, please contact Larson and Associates at 253-474- 3404 for a specific BMP activity type. REQUIRED ACTIONS OF ALL OWNERS The following actions shall be taken by all owners to ensure that pollution generated on Chelan Creek Lot 2 project is minimized. 1) Paved roadways shall be swept twice a year. It is recommended that newer high-velocity vacuum sweeper be used. 2) The storm drainage system shall be maintained per Attachment “A” 3) No activities shall be conducted on the property that is likely to result in a short-term high concentration discharge of pollution to the storm system. Such activities shall include, but are not limited to car washes, vehicle maintenance, and cleaning of equipment and or vehicles, unless the project has been properly permitted for such uses and the BMP’s for such uses have been received by the owner. 4) Automobile fluids, chemicals etc. shall be disposed of legally and properly. 5) All garbage shall be contained in appropriate containers. 4.3 BMPs TO CONSIDER FOR ALL ACTIVITIES This is a summary of items that each business/homeowner should consider. As stated before, most of these are common sense, housekeeping types of solutions, but if each business/homeowner would take some action on each of these, the improvement in water quality would be substantial. 1. Avoid the activity or reduce its occurrence If you can, avoid the activity or do it less frequently. If there a substitute process or a different material you can use to get the job done? Can you do a larger run of a process at one time, thus reducing the number of times per week or month it needs to be repeated? For instance, raw materials could be delivered close to the time of use instead of being stockpiled and exposed to the weather. Perhaps you could avoid one solvent-washing step altogether. The Department of Ecology or the King County Health Department can provide pollution prevention assistance. 2. Move the activity indoors Sometimes it is fairly easy to move an activity indoors out of the weather. The benefits of this are twofold; you prevent runoff contamination, and you provide for easier, more controlled cleanup if a spill occurs. An example would be unloading and storing barrels of chemicals inside a garage area instead of doing it outside. Please be aware that moving storage areas indoors may require installation of fire suppression equipment or other building modifications as required by the Uniform Building Code, the Uniform Fire Code, or local ordinances. 3. Use less material Don’t buy or use more material than you really need. This not only helps keep potential disposal, storage and pollution problems to a minimum, but will probably save you money, too. 4. Use the least toxic materials available Investigate the use of materials that are less toxic than what you use now. Perhaps a caustic-type detergent or a solvent could be replaced with a more environmentally friendly product. Such a change might allow you to discharge process water to the sanitary sewer instead of paying for expensive disposal. Remember that even if you do switch to a biodegradable product, nothing but uncontaminated water is allowed to enter the storm drain system. 5. Create and maintain vegetated areas near activity locations Vegetation of various kinds can help filter pollutants out of stormwater, so it is advisable to route stormwater through vegetated areas located near your activity. For instance, many parking lots contain grassy islands, typically formed in a “hump”. By creating those islands as depressions instead of humps, they can be used to treat runoff from the parking lot or roof. Also, don’t forget the erosion control benefits of vegetation at your site. 6. Locate activities as far as possible from surface drainage paths Activities located as far as possible from known drainage paths, ditches, streams, and drains will be less likely to pollute, since it will take longer for material to reach the drainage feature. This gives you more time to react in the event of a spill, or if it is a “housekeeping” issue may protect the local waters long enough for you to clean up the area around the activity. Don’t forget that groundwater issues are always prominent, no matter where the activity is located so the actions taken on your site on a day-to-day basis are always important, even in dry weather. 7. Keep storm drain systems clean Pollutants can concentrate over time in storm drainage structures such as catch basins, ditches and storm drains. When a large storm event occurs, it can mobilize these pollutants and carry them to receiving waters. Develop and implement maintenance practices, inspections, and schedules for treatment devices (e.g., detention ponds, oil/water separators, vegetated swales, etc.). Requirements for cleaning catch basins will be discussed later in the specific BMP S.9. 8. Reduce, reuse and recycle as much as possible Always look for ways to recycle instead of just disposing. This can save money as well as keep both hazardous and non-hazardous materials out of the landfills. You can learn more about other businesses that have made process changes allowing recycling of chemicals by calling the DOE at 1-800-RECYCLE and requesting publication #9245 and 90-22. Another unique recycling opportunity for businesses is available through the “matchmaker”, helping one company’s waste become another company’s asset. For instance, waste peach pits from a cannery become potpourri ingredients to another’s business. Call IMEX at 206-625-623 to list your potentially usable solid or chemical waste in their publication. 9. Be an advocate for stormwater pollution prevention Help friends, partners and business associates find ways to reduce stormwater pollution in their activities. Most people want clean water, and do not pollute intentionally. Share your ideas and the BMPs in this manual to get them thinking about how their everyday activities affect water quality. 10. Report Violators Allowing anyone to pollute our waters is wrong. We all must do our part to protect water, fish, wildlife and our own health, by employing proper BMPs, and reporting those who are causing pollution.. STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN II-5.10 BMPS FOR SMALL PARCELS A Small Parcel Stormwater Management Plan must be developed which satisfies the Small Parcel Minimum Requirements found in Volume II, Chapter II-2. These in turn may be satisfied by employing a suitable selection from the following list of BMPs. BMP ES.10 PLANNED CLEARING AND GRADING Plan and implementation proper clearing and grading of the site. It is most important only to clear the areas needed, thus keeping exposed areas to a minimum. Phase clearing so that only those areas that are actively being worked are uncovered. Note: Clearing limits should be flagged in the lot or area prior to initiating clearing. BMP ES.20 EXCAVATING BASEMENT SOIL Located excavated basement soil a reasonable distance behind the curb, such as in the backyard or side yard area. This will increase the distance eroded soil must travel to reach the storm sewer system. Soil piles should be covered until the soil is either used or removed. Piles should be situated so that sediment does not run into the street or adjoining yards. BMP ES.30 BACKFILLING Backfill basement walls as soon as possible and rough grade the lot. This will eliminate large soil mounds which are highly erodible and prepares the lot for temporary cover which will further reduce erosion potential. BMP ES.40 REMOVAL OF EXCESS SOIL Remove excess soil from the site as soon as possible after backfilling. This will eliminate any sediment loss from surplus fill. BMP ES.50 MANAGEMENT OF SOIL BANKS If a lot has a soil bank higher than the curb, a trench or berm should be installed moving the bank several feet behind the curb. This will reduce the occurrence of gully and hill erosion while providing a storage and settling area for stormwater. BMP ES.60 CONSTRUCTION ROAD ACCESS Apply gravel or crushed rock to the driveway area and restrict truck traffic to this one route. Driveway paving can be installed directly over the gravel. This measure will eliminate soil from adhering to tires and stops soil from washing into the street. This measure requires periodic inspection and maintenance including washing, top-dressing with additional stone, reworking and compaction. (For further details see BMP E2.10, Chapter II-5.7.1). BMP ES.70 SOIL STABILIZATION Stabilized denuded areas of the site by mulching, seeding, planting, or sodding. For further details on standards and specifications, see BMPs No. E1.10, E1.15, E1.35, E1.40 in Chapter II-5. BMP ES.80 STREET CLEANING Provide for periodic street cleaning to remove any sediment that may have been tracked out. Sediment should be removed by shoveling or sweeping and carefully removed to a suitable disposal area where it will not be re-eroded. II-5.11 References (1) Goldman, Steven J., Erosion and Sediment Control Handbook, McGraw-Hill, 1986. (2) Horner, Richard R., Juno Guedry and Michael H. Kortenhof, Highway Construction Site Erosion and Pollution Control Manual, Washington State Department of Transportation with the United States Department of Transportation Federal Highway Administration, WA-RD 200.2, January, 1990. (3) Metro, Summary of Preliminary Data Analysis – BMP Survey of Single Family Residential Construction Sites, January, 1984. (4) Brandy, Nile C., The Nature and Properties of Soils, Eight Edition, MacMillan, 1974. BEST MANAGEMENT PRACTICES FOR SINGLE-FAMILY RESIDENCES The actions we take each day in and around cur homes have a profound effect on stormwater quality in this region. Small amounts of pollution from many different sources can significantly affect our waterways. Yard maintenance, waste storage, car washing and maintenance, and pool cleaning are some of the activities that can adversely impact water quality. The best management practices (BMPS) discussed in this section are practical ways to keep stormwater from becoming polluted in the first place. It is recommended that all residences in King County use these BMPS. Please note that some of these procedures are required by various state, federal, or county laws, and are noted as required BMPS. 3.1 AUTOMOBILE WASHING Most residents wash their cars in the driveway or on the street. Washwaters typically flow to a storm drain or ditch, which discharges stormwater directly to the nearest stream, lake or to Puget Sound. Soaps and detergents, even the biodegradable ones, can have immediate and long-term effects on critters living in waterbodies. The grime washed off the car also contains a variety of pollutants that can harm fish and wildlife. Suggested BMPs  Wash your car directly over your lawn or make sure the wash water drains to a vegetated area. This allows the water and soap to soak into the ground instead of running off into a local waterbody.  Ideally, no soaps or detergents should be used, but if you do use one, select one without phosphates.  Sweep driveways-and street gutters before washing vehicle to clean up dirt, leaves, trash and other materials that may flow to the storm drain along with your wash water. This helps reduce storm drain maintenance costs as well as protect water quality.  Commercial products are available that allow you to clean a vehicle without water. These were developed for areas where water is scarce, so a water saving benefit is realized as well as reduced pollution.  Use a nozzle on your hose to save water.  Do not wash your car if rain is expected.  Consider not washing your car at home. Take it to a commercial car wash that has a recycle system and discharges wastewater to the sanitary sewer for treatment. 3.2 AUTOMOBILE MAINTENANCE Many of us are "weekend mechanics". We enjoy the cost savings of changing our own oil and antifreeze, topping off the battery with water, and generally making our car ' perform its best. There are many potentials for stormwater pollution associated with these activities, however, the following BMPs will - help you minimize pollution while servicing your car. Required BMPs  Recycle all oils, antifreeze, solvents and batteries. Many local car parts dealers and gas stations accept used oil. Call shops listed under Batteries in the Yellow Pages of the phone book to find out if they are paying for used batteries. Use the numbers listed in Chapter 7 to call for more information.  Never dump new or used automotive fluids or solvents on the ground, in a storm drain or street gutter, or in a waterbody. Eventually, it will make its way to local surface waters or groundwater, including the water we drink.  Do not mix wastes. The chlorinated solvents in some carburetor cleaners can contaminate a huge tank of used oil, rendering it unsuitable for recycling. Always keep your wastes in separate containers which are properly labeled and store them out of the weather. Suggested BMPs  To dispose of oil filters, punch a hole in the top and let drain for 24 hours. This is where a large funnel in the top of your oil storage container will come in handy. After draining, wrap in 2 layers of plastic and dispose of in your regular garbage or recycle by taking it to a local Landfill Household Hazardous Waste facility. Pending State law may make disposal in your home garbage illegal, so please call the Hazardous Waste line at 1-800-287-6429 for up-to-date information.  Use care in draining and collecting antifreeze to prevent accidental spills. Spilled antifreeze can be deadly to cats and dogs that ingest it.  Perform your service activities on concrete or asphalt or over a plastic tarp to make spill clean-up easier. Keep a bag of kitty litter on hand to absorb spills. Sprinkle a good layer on the spill, let it absorb for a little while and then sweep it up. Place the contaminated litter in a plastic bag,' tie it up, and dispose of it in your regular garbage. Take care not to leave kitty litter out in the rain; it will form a sticky goo that is hard to clean up.  If you are doing bodv work outside, be sure to use a tarp to catch material resulting from grinding, sanding and painting. Dispose of this waste by double bagging in plastic and placing in your garbage. 3.3 STORAGE OF SOLID WASTES AND FOOD WASTES Improper storage of food and solid waste at residences can lead not only to water pollution problems, but problems with neighborhood pets and vermin as well. Following the BMPs listed below can help keep your property a clean and healthy place to live. Suggested BMPs  All waste containers kept outside should have lids.  Leaking waste containers should be replaced.  Store waste containers under cover if possible, or on grassy areas.  Inspect the storage area regularly to pick up loose scraps of material and dispose of them properly.  Recycle as much as you can. King County offers curbside recycling to a majority of residents. Also, look under "Recycling" in the phone book for firms which take other recyclables.  Purchase products which have the least amount of packaging materials.  Compost biodegradable materials such as grass clippings and vegetable scraps instead of throwing them away. Your flower beds will love the finished compost, and we won't fill up our landfills so quickly. See the section on Composting for BMPs relating to that activity.  A fun alternative to traditional composting is worm composting. You can let worms do all the work for you by keeping a small vermiculture box just outside your kitchen. For more information on getting started with worms, call the numbers listed above. 3.4 COMPOSTING Composting is an earth-friendly activity as long as some common sense rules outlined below are followed. If you choose to compost, the following BMPs should be utilized. Suggested BMPs  Compost piles must be located on an unpaved area where runoff can soak into the ground or be filtered by grass and other vegetation. Compost piles should be located in an area of your yard not prone to water ponding during storms, and should be kept well away from wetlands, streams, lakes and other drainage paths.  Avoid gutting hazardous or non-decomposable waste in the pile.  Cover the compost pile for two reasons: 1. To keep stormwater from washing nutrients into waterways. 2. To keep excess water from cooling down the pile, which will slow down the rate of decomposition.  Build bins of wood, chicken wire or fencing material to contain compost so it can't be washed away.  Building a small earthen dike around your compost pile is an effective means of preventing nutrient- rich compost drainage from reaching stormwater paths. 3.5 YARD MAINTENANCE AND GARDENING This section deals with the normal yard maintenance activities we all perform at our homes. Overwatering, overfertilizing, improper herbicide application and improper disposal of trimmings and clippings can all contribute to serious water pollution problems. Following the BMPs listed below will help alleviate pollutant runoff. Required BMPs  Follow the manufacturers directions exactly for mixing and applying herbicides, fungicides and insecticides, and use them sparingly. Never apply when it is windy or when rain is expected. Never apply over water, within 100 feet of a well-head, or adjacent to streams or other waterbodies. Triple- rinse empty containers, using the rinsate for mixing your next batch of spray, and then double-bag and dispose of the empty container in your regular garbage.  Never dispose of grass clippings or other vegetation in or near storm drains, streams, lakes or Puget Sound. Suggested BMPs  Follow manufacturers directions when applying fertilizers. More is not better, either for your lawn or for local waterbodies. Never apply fertilizers over water or adjacent to ditches, streams or other water bodies. Remember that organic fertilizers have a slow release of nitrogen, and less potential to pollute than synthetic fertilizers.  Save water and-prevent pollution problems by watering your lawn sensibly. Lawns and gardens typically need the equivalent of 1" of rainfall per week. You can check on how you're doing by putting a wide mouth jar out where you're sprinkling, and measure the water with a small plastic ruler. Overwatering to the point of runoff can carry polluting nutrients to the nearest waterbody.  Consider planting a vegetated buffer zone adjacent to streams or other water bodies on your property.  Make sure all fertilizers and pesticides are stored in a covered location. Rain can wash the labels off of bottles and convert 50 lbs. of fertilizer into either a solid lump or a river of nutrients.  Compost all yard clippings, or use them as mulch to save water and keep down weeds in your garden. See Composting section for more information.  Practice organic gardening and virtually eliminate the need to use pesticides and fertilizers. Contact the Ask-A-Master Gardener program at (253) 798-7170 for information and classes on -earth-friendly gardening.  Pull weeds instead of spraying and get some healthy exercise, too. If you must spray, use the least toxic formulations that will get the job done. The Master Gardener program listed above can help advise you on which spray to use.  Work fertilizers into the soil instead of letting them lie on the ground surface exposed to the next rain storm.  Contact your local garbage hauler for curbside pickup and recycling of yard waste. 3.6 SWIMMING POOL AND SPA CLEANING AND MAINTENANCE Despite the fact that we immerse ourselves in it, the water from pools and spas is far from chemically clean. Nutrients, pH, and chlorine can adversely affect fish and wildlife in waterbodies. Following these BMPs will ensure the cleanliness of your pool and the environment. Required BMPs  Pool and spa water must be dechlorinated if it is to be emptied into a ditch, on the ground, or a lawn or to the storm drainage system. Contact your pool chemical supplier to obtain the neutralizing chemicals you will need. The rate of flow into the ditch or drainage system must be regulated so that it does not cause problems such as erosion, surcharging or flooding. You must obtain permission from King County Surface Water Management prior to discharging into any county ditch or facility. Water discharged to the ground or a lawn must not cross property lines and must not produce runoff. If you live-in a sewered area, you must discharge pool water to the sanitary sewer.  If pool and spa water cannot be dechlorinated, it must be discharged to the sanitary sewer. Prior to draining, your local wastewater treatment plant must be notified to ensure they are aware of the volume of discharge and the potential effects of chlorine levels. A pool service company can help you determine the frequency of cleaning and backwash of filters.  Diatomaceous earth used in pool filters cannot be disposed of in surface waters, on the ground, into storm drainage systems or septic systems. Dry it out as much as possible, bag it in plastic, and dispose of at the landfill. Suggested BMPs  Hire a professional pool service company to collect all pool water for proper disposal. Make sure to ask them where they will dispose of it and the kind of permits they hold to do so. 3.7 HOUSEHOLD HAZARDOUS MATERIAL USE, STORAGE, AND DISPOSAL Once we really start looking around our houses, the amount of hazardous materials we have on site is a real eye-opener. Oil-based paints and stains, paint thinner, gasoline, charcoal starter fluid, cleaners, waxes, pesticides, fingernail polish remover, and wood preservatives are just a few that most of us have around the house. When products such as these are dumped on the ground or in a storm drain, they can be washed directly to receiving waters where they can harm fish and wildlife. They can also infiltrate into the ground and contaminate drinking water supplies. The same problem can occur if they are disposed of with your regular garbage; the containers can leak at the landfill and contaminate groundwater. The same type of contamination can occur if hazardous products are poured down a sink or toilet into a septic system. Don't pour them down the drain if you're on municipal sewers, either. Many compounds will "pass through" the wastewater treatment plant without treatment and contaminate receiving waters, or they can harm the biological process used at the treatment plant, reducing overall treatment efficiency. With such a diversity of hazardous products present in all homes in King County, a large potential for serious environmental harm-exists if improper methods of storage, usage and disposal are employed. Using the following BMPs will help keep these materials out of our soils, sediments and waters. Required BMPs  Dispose of hazardous materials and their containers properly. Never dump products labeled as poisonous, corrosive, caustic, flammable, inflammable, volatile, explosive danger, warning, caution or dangerous outdoors, in a storm drain, or into sinks, toilets or drains. Suggested BMPs  Check containers containing hazardous materials frequently for signs of leakage. If a container is rusty and has the potential of leaking soon, pace it in a secondary container before the leak occurs and prevent a clean-up problem.  Store hazardous materials containers under cover and off the ground. Keep them out of the weather to avoid rusting, freezing, cracking, labels being washed off, etc.  Hazardous materials should be stored out of the reach of children. Never transfer to or store these materials in food or beverage containers which could be misinterpreted by a child as something to eat or drink.  Keep appropriate spill cleanup materials on hand. Kitty litter is good for many oil-based spills.  Ground-cloths and drip pans must be used under any work outdoors which involves hazardous materials such as oil-based paints, stains, rust removers, , masonry cleaners, and others bearing label warnings as outlined above.  Latex paints are not a hazardous waste, but are not accepted in liquid form at the landfill. To dispose, leave uncovered in a protected place until dry, then place in the garbage. If you wish to dry waste paint quickly, just pour kitty litter in the can to absorb the paint. Once paint is dry, leave the lid off when you place it in the garbage so your garbage collector can see that it is no longer liquid.  Use less toxic products whenever possible. The Hazardous Waste Line at l (800) 287-6429, and the Washington Toxics Coalition at (206) 632-1545 have information detailing alternatives to toxic products.  If an activity involving the use of a hazardous material can be moved indoors out of the weather, then do so. Make sure you can provide proper ventilation, however.  Follow manufacturers' directions in the use of all materials. Over-application of yard chemicals, for instance, can result in the washing of these compounds into receiving waterbodies. Never apply pesticides when rain is expected.  When hazardous materials are in use, place the container inside a tub or bucket to minimize spills. APPENDIX “B” CONSTRUCTION SWPPP AND BMP’S LARSON & ASSOCIATES, INC. SURVEYORS, ENGINEERS AND PLANNERS 9027 PACIFIC AVENUE, SUITE 4 TACOMA, WA 98444 (253) 474-3404