The Method of Evaluating The Potential for Conversion Legal Problems with Conversion And Basic Capacity of Vacant Onces in Tokyo
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- 한국주거학회:학술대회논문집
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- 한국주거학회 2002년도 추계학술발표대회
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- pp.301-306
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- 2002
In Japan, the vacancy rates of office buildings have been at high in big cities since 1992. This problem is especially acute in Tokyo, where it is estimated that over 2.27 million square meters of office floor area will be oversupplied in 2003: big urban redevelopment projects will be completed in 2003. Under these circumstances, International Cooperative Research and Development on Sustainable Urban Management by Conversion of Buildings, called “SUMCOB”, has been carried out. This research aims to regenerate urban areas by converting redundant offices into flats, although instances of conversion are still very few in Japan. This paper introduces part of current results by SUMCOB, and discusses legal problems with conversion and basic capacity of vacant offices in Tokyo. It has been confirmed that there are no constraints concerned with Real Estate Registration Law (although it requires the change of the registration after conversion). and City Planning Law. However, some criteria are incompatible with Building Standard Law and Fire Service Law if the use of the building is changed from offices to flats. Typical incompatibility between offices and flats is lightening. If the buildings do not satisfy criteria for flats, the cost of renovation works for conversion will increase. To examine the basic capacity of vacant office buildings for conversion, field surveys in Tokyo have carried out at three areas: Kodenmacho (Chuo-ku), Toranomon (Minato-ku), and Iwamonocho (Chiyoda-ku). They are typical office areas that are included in center core of Tokyo. In Chuo-ku, the oldest commercial area in Tokyo, textile merchants have been located their headquarters. In Minato-ku, many rental office buildings have been located and several large scale redevelopments are advancing. Chiyoda-ku includes Marunouchi area, which is the prime office area in Japan. Thirty percent of the buildings in survey areas suffer from over twenty percent vacant floor rate, and fifty five percent were constructed before 1990. Especially most of buildings over forty percent vacant floor rate were constructed in 1980s. Vacant office problems haven't been seen in old buildings in Tokyo yet. The number of dwelling units made from office space will influence the conversion scheme. Seventy percent of the office buildings in survey areas have floor area of less than two hundred square meters. If they have been subdivided into two bedrooms type or three bedrooms type, the number of dwelling units in a floor would be less than three. The difficulty of conversion planning derives from frontage size, depth size, and their proportion. The five categories are proposed to grasp actual requirements for converting offices into flats.
Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.